US 20110144244A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2011/0144244 A1 Lee (43) Pub. Date: Jun. 16, 2011

(54) HALOGEN-FREE FLAME RETARDANT CSK 5/05 (2006.01) MATERAL CSK 5/545 (2006.01) CSK 5/535 (2006.01) (75) Inventor: Jean L. Lee, San Jose, CA (US) CSK 5/45 (2006.01) (52) U.S. Cl...... 524/84; 524/429; 524/405; 524/442: (73) Assignee: Apple Inc., Cupertino, CA (US) 524/443; 524/431; 524/425; 524/424; 524/186: 524/383,524/110:524/111 (21) Appl. No.: 12/638,489 (57) ABSTRACT (22) Filed: Dec. 15, 2009 The disclosure describes halogen free flame retardant resin compositions comprising at least one thermoplastic polymer; Publication Classification an inorganic filler; and a flame retardant additive, wherein the (51) Int. Cl. flame retardant additive is an alkali metal nitrite; an alkaline CSK 3/28 (2006.01) earth metal nitrite; an alkali metal nitride; an alkaline earth CSK 3/38 (2006.01) metal nitride; an alkali metal borate; an alkaline earth metal C08K 3/34 (2006.01) borate; an alkali metal silicide; an alkaline earth metal sili CSK 3/22 (2006.01) cide; an alkali metal silicate; or an alkaline earth metal sili C08K 3/26 (2006.01) cate. Also described are computing systems having compo CSK 5/17 (2006.01) nents formed of Such a halogen free, flame retardant resin. Patent Application Publication Jun. 16, 2011 US 2011/O144244 A1

AA US 2011/0144244 A1 Jun. 16, 2011

HALOGEN-FREE FLAME RETARDANT moplastic polymer can be present, for example, in about 30 MATERAL wt.% to about 70 wt.% of the composition. 0007. The inorganic filler can be one or more of carbon BACKGROUND black, white carbon, silica, Zirconium silicate, alumina, hydrated alumina, aluminum trihydrate, hydrated magne 0001. It has been estimated that about 10% of fires are sium, barium sulfate, barium titanate, titanium oxide, mag caused by electrical faults of wiring and electrical equipment, nesium oxide, molybdenum oxide, tin oxide, Zinc oxide, talc, and that these fires account for 19% of fire-related injuries. mica, glass beads, hollow glass balls, clay, silicone oil, quartz, Some plastics are inherently resistant to fire, such as polyvi barium carbonate, calcium carbonate, or magnesium carbon nylchloride (PVC). However, PVC is not suitable for many ate. In some embodiments, one or more of Such inorganic electronics applications. Only about 12% of plastics used fillers can also be excluded from the composition. The inor today contain flame retardants. An increased use of flame ganic filler can be present, for example, in about 1 wt.% to retardants would improve the safety of electrical wiring and about 30 wt.% of the composition. electronic devices, and therefore reduce the number of fires 0008. In some embodiments, the flame retardant additive caused by electronic devices. can include an alkali metal nitrite or an alkaline earth metal 0002 Halogenated flame retardants have been found to be nitrite. The alkali metal nitrite or alkaline earth metal nitrite effective in many plastics. However, environmental and can be, for example, lithium nitrite, Sodium nitrite, potassium health concerns have caused halogenated flame retardants to nitrite, magnesium nitrite, or calcium nitrite. be less desirable for electronic devices, and they are being 0009. In some embodiments, the flame retardant additive increasingly regulated. can include an alkali metal nitride or an alkaline earth metal 0003) A wide variety of flame retardant resin composi nitride. The alkali metal nitride or alkaline earth metal nitride tions have been developed to ensuring safety against fire, can be, for example, lithium nitride, magnesium nitride, including halogen free flame retardant resin compositions. beryllium nitride, or calcium nitride. Generally, halogen free flame resisting resin compositions 0010. In some embodiments, the flame retardant additive contain inorganic fillers, such as aluminum hydroxide or can include an alkali metal borate or an alkaline earth metal magnesium hydroxide. The amount of the inorganic filler borate. The alkali metal borate or alkaline earth metal borate required to obtain sufficiently high flame resisting effect is can be, for example, sodium metaborate, Sodium tetraborate, generally 30 to 70% by weight based of the composition. NaBas, NaB. NaBs, calcium aluminum triborate (jo However, a synthetic resin composition containing Such high hachidolite), magnesium diboride, Suanite; johachidolite; contents of inorganic filler generally do not exhibit suitable LiBO, LiBO, CaBO, Sodium metaborate; sodium tet physical characteristics, such as well-balanced strength, raborate; NaBOs (OH)8H2O, or disodium octaborate tet resulting in brittle products with poor processability. Accord rahydrate. ingly, there is a need for new halogen-free flame retardants, as 0011. In some embodiments, the flame retardant additive well as new halogen-free plastics and resin materials. can include an alkali metal silicide oran alkaline earth metal silicide. The alkali metal silicide or alkaline earth metal sili SUMMARY cide can be, for example, Sodium silicide, potassium silicide, 0004. The invention provides halogen-free flame retar rubidium silicide, cesium silicide magnesium silicide, or cal dants, resins that include halogen free flame retardants, and cium silicide. plastic components made from Such materials. In some 0012. In some embodiments, the flame retardant additive embodiments, the invention relates to a composite resin can include an alkali metal silicate or an alkaline earth metal molded article having excellent flame retardancy, electric silicate. The alkali metal silicate or alkaline earth metal sili insulation properties, and crack resistance, and produces only cate can be, for example, thaumasite, olivine; or epidote. negligible amounts of toxic Substances during incineration, if 0013 Any given embodiment can also include an antioxi any at all. dant, such as an amino acid, Vitamin A, vitamin E, ascorbic 0005 Accordingly, the invention provides a halogen free acid, or lipoic acid. Antioxidants can be included in about 0.5 resin composition that includes at least one thermoplastic parts to 15 parts by weight, or in about any 0.5 part increment polymer; an inorganic filler; and a flame retardant additive, within Such a range. In some embodiments, the composition wherein the flame retardant additive comprises an alkali can have a melt index of, for example, about 0.1 g/10 minutes metal nitrite; an alkaline earth metal nitrite; an alkali metal to about 10.0 g/10 minutes. nitride; an alkaline earth metal nitride; an alkali metal borate; 0014. In some embodiments, a halogen free resin compo an alkaline earth metal borate; an alkali metal silicide; an sition includes about 70 parts to 30 parts by weight of at least alkaline earth metal silicide; an alkali metal silicate; an alka one thermoplastic polymer; about 30 parts to 70 parts by line earth metal silicate; or a combination thereof. weight of an inorganic filler; and about 0.5 parts to 15 parts by 0006. The thermoplastic polymer can include one or more weight of a flame retardant additive, wherein the flame retar of polyethylene (PE); ethylene-vinyl acetate copolymer dant additive includes an alkali metal nitrite; an alkaline earth (EVA); ethylene-ethyl acrylate copolymer (EEA): ethylene metal nitrite; an alkali metal nitride; an alkaline earth metal methyl methacrylate copolymer (EMMA); polypropylene nitride; an alkali metal borate; an alkaline earth metal borate; (PP); polystyrene (PS); polyacrylonitrile; acrylonitrile-buta an alkali metal silicide; an alkaline earth metal silicide; an diene-styrene copolymer (ABS), nylon-6, nylon-6.6; poly alkali metal silicate; an alkaline earth metal silicate; or a carbonate (PC); polyurethane; biaxially-oriented polyethyl combination thereof. ene terephthalate (boPET) polyester; ethylene-C.-olefin 0015 The invention further provides a computing system, copolymer, ethylene-vinyl ester copolymers; ethylene-C.f3 input device, or computer component comprising any of the unsaturated carboxylic acid alkyl ester copolymers; poly compositions described above or herein. For example, a com (acrylic acid); or polyphenylene sulphone (PPS). The ther puting system can include at least one component selected US 2011/0144244 A1 Jun. 16, 2011

from the group consisting essentially of a housing, an input indicate that the embodiment described may include a par device, and a cable, wherein the component includes a halo ticular aspect, feature, structure, moiety, or characteristic, but gen free resin, that includes at least one thermoplastic poly not every embodiment necessarily includes that aspect, fea mer, an inorganic filler, and a flame retardant additive, ture, structure, moiety, or characteristic. Moreover, Such wherein the flame retardant additive comprises an alkali phrases may, but do not necessarily, refer to the same embodi metal nitrite; an alkaline earth metal nitrite; an alkali metal ment referred to in other portions of the specification. Further, nitride; an alkaline earth metal nitride; an alkali metal borate; when a particular aspect, feature, structure, moiety, or char an alkaline earth metal borate; an alkali metal silicide; an acteristic is described in connection with an embodiment, it is alkaline earth metal silicide; an alkali metal silicate; an alka line earth metal silicate; or a combination thereof. within the knowledge of one skilled in the art to affect such 0016. In some embodiments, a flame retardant resin is aspect, feature, structure, moiety, or characteristic in connec provided that does not include carbon black. The resins are tion with other embodiments, whether or not explicitly therefore widely applicable to the fields where colored prod described. ucts are desirable. Such as products where appearance has 0023 The term “and/or means any one of the items, any commercial significance. Examples of such products include combination of the items, or all of the items with which this personal electronic devices, such as personal computers, lap term is associated. top computers, cell phones, personal digital assistants, elec 0024. The singular forms “a,”& G “an& G and “the include plu tronic games, and the like. ral reference unless the context clearly dictates otherwise. 0017. The invention also relates to a self-fire extinguish Thus, for example, a reference to “a compound includes a able, halogen-free and flame resisting synthetic resin compo plurality of such compounds, so that a compound X includes sition. Such a composition can be obtained by adding 0.5 to a plurality of compounds X. It is further noted that the claims 15 parts by weight of a flame retardant additive as described may be drafted to exclude any optional element. As such, this herein to a mixture comprising 70 to 30 parts by weight of a statement is intended to serve as antecedent basis for use of thermoplastic synthetic resin and 30 to 70 parts by weight of such exclusive terminology as “solely.” “only, and the like in an inorganic filler, Such as magnesium hydroxide or alumi connection with the recitation of claim elements, or use of a num hydroxide having an average particle size of 0.1 to 10 “negative' limitation. lm. 0025. The term “about can refer to a variation of +5%, 0.018. The flame retardant materials can be effective flame +10%, +20%, or +25% of the value specified. For example, retardants in standard and technical plastics, thermosets, tex “about 50 percent can in some embodiments carry a varia tiles, and rubbers. The invention also provides a prepreg tion from 45 to 55 percent. For integer ranges, the term impregnated with the halogen-free flame-retardant epoxy "about can include one or two integers greater than and/or resin composition according to the invention as well as a less than a recited integer. Unless indicated otherwise herein, laminate, copper-clad laminate and printed wiring board pre the term “about is intended to include values, e.g., weight pared by using the prepreg. percents, proximate to the recited range that are equivalent in terms of the functionality of the individual ingredient, the BRIEF DESCRIPTION OF THE DRAWINGS composition, or the embodiment. 0019. The following drawing forms part of the specifica 0026. As will be understood by one skilled in the art, for tion and is included to further demonstrate certain embodi any and all purposes, particularly in terms of providing a ments or various aspects of the invention. In some instances, written description, all ranges disclosed herein also encom embodiments of the invention can be best understood by pass any and all possible Subranges and combinations of referring to the accompanying drawing in combination with Subranges thereofas well as the individual values making up the detailed description presented herein. The description and the range, particularly integer values. A recited range (e.g., accompanying drawing may highlight a certain specific weight percents or carbon groups) includes each specific example, or a certain aspect of the invention, however, one value, integer, decimal, or identity within the range. Any skilled in the art will understand that portions of the example listed range can be easily recognized as Sufficiently describ or aspect may be used in combination with other examples or ing and enabling the same range being broken down into at aspects of the invention. least equal halves, thirds, quarters, fifths, tenths, etc. As a non 0020 FIG. 1 illustrates an example computing system of a limiting example, each range discussed herein can be readily type that can include parts made of, and that can benefit from broken down into a lower third, middle third and upper third, use of a halogen free resin composition as described herein, etc. As will also be understood by one skilled in the art, all in one illustrative operating configuration. language Such as “up to.” “at least,” “greater than.” “less than,”“more than,” “or more' and the like include the number DETAILED DESCRIPTION recited and refer to ranges which can be subsequently broken down into Subranges as discussed above. In the same manner, Definitions all ratios disclosed herein also include all subratios falling 0021. As used herein, certain terms have the following within the broader ratio. meanings. All other terms and phrases used in this specifica 0027. One skilled in the art will also readily recognize that tion have their ordinary meanings as one of skill in the art where members are grouped together in a common manner, would understand. Such ordinary meanings may be obtained Such as in a Markush group, the invention encompasses not by reference to technical dictionaries, such as Hawley's Con only the entire group listed as a whole, but each member of the densed Chemical Dictionary 14" Edition, by R. J. Lewis, group individually and all possible Subgroups of the main John Wiley & Sons, New York, N.Y., 2001. group. Additionally, for all purposes, the invention encom 0022 References in the specification to “one embodi passes not only the main group, but also the main group ment”, “an embodiment”, “an example embodiment, etc., absent one or more of the group members. The invention also US 2011/0144244 A1 Jun. 16, 2011

envisages the explicit exclusion of one or more of any of the 0036 an alkali or alkaline earth nitride; group members in the claimed invention. 0037 an alkali or alkaline earth nitrite; 0028. As will be understood by the skilled artisan, all 0038 an alkali or alkaline earthborate; numbers, including those expressing quantities of ingredi 0039 an alkali or alkaline earth silicide: ents, properties such as molecular weight, reaction condi 0040 an alkali and alkaline earth silicate; 0041 an antioxidant compound, such as amino acids (e.g., tions, and so forth, are approximations and understood as glutathione), polyphenols, carotenoids, tocotrienols, ascorbic being modified in all instances by the term “about.” These acid, and/or lipoic acid; or salts thereof; values can vary depending upon the desired properties sought 0042 or a combination thereof. to be obtained by those skilled in the art utilizing the teachings 0043. The flame retardant additives can be added to a resin of the invention. It is also understood that such values inher to Scavenge high energy ions that may be released by a burn ently contain variability necessarily resulting from the stan ing resin. The flame retardant resins can be used to provide dard deviations found in their respective testing measure flame proof or flame resistant apparatuses constructed of a mentS. halogen-free flame retardant material as described herein. 0029. The phrase “one or more' is readily understood by 0044 Flame Retardant Activity. Solid materials do not one of skill in the art, particularly when read in context of its burn directly. They first decompose by heat (e.g., pyrolysis) to usage. For example, one or more substituents on a phenyl ring release flammable gases. Visible flames appear when these refers to one to five, or one to up to four, for example if the flammable gases react with oxygen (O) in the air. If solid phenyl ring is disubstituted. materials do not break down into gases, they merely Smolder 0030 The term “contacting refers to the act of touching, and often self extinguish. An example of self extinguishing is making contact, or of bringing to immediate or close proX when a solid chars and forms a stable carbonaceous barrier imity, including at the molecular level, for example, to bring that prevents access of a flame to the underlying material. about a chemical reaction, or a physical change, e.g., on the However, once flammable gases from a solid ignite, the heat Surface of a solidor in the gas phase near the Surface of a solid. generated can often break down long-chain solid molecules 0031 Specific values listed below for radicals, substitu (e.g., polymer chains) into Smaller molecules that transpire as ents, and ranges, are for illustration only; they do not exclude gases, fueling the fire. The gas flame itself is maintained by other defined values or other values within defined ranges for the action of high energy radicals (H. and OH. in the gas radicals and Substituents. phase), which decompose nearby molecules to produce free 0032. The term “halogen free” refers to a composition that carbon, which then reacts with oxygen in the air to burn, includes less than 900 parts per million of halogen content, generating additional heat energy. including, for example, the cumulative mass of chlorine 0045. Flame retardants work by preventing the release of containing and bromine-containing components (i.e., the flammable gases from a material when an amount of heat mass of the chlorine-containing and bromine-containing capable of igniting the material is applied. Depending on the components added to the resin formulation). specific molecule that is decomposed by high energy ions, flammable gases such as O. are often released, further Sus Description of the Halogen Free Flame Retardant Composi taining a flame. Flame retardants act by effectively removing tions. the H. and OH. radicals in the gas flame phase. This action considerably slows or prevents the burning process, thus 0033. As consumer electronics manufacturers phase out reducing heat generation and the production of further gas the use of brominated and chlorinated flame retardant mate eous flammable material. rials due to environmental concerns, alternate materials must 0046 Char Formation. The flame retardant compositions be developed to fill the Void. The compositions described described herein can act efficiently in the solid phase of herein provide halogen-free (HF) flame retardant materials burning materials. When heated, the flame retardants can by introducing alkali or alkaline earth metal nitrites, nitrides, react to produce high energy radical quenching agents. Such borides, and/or silicates into materials, such as cross-linked as low energy radicals or acids. The low energy radicals or polyethylene (often used for electrical cable jackets and the acids can cause the Solid material to further polymerize and/ like). The HF flame retardant materials can suppress combus or char, forming a glassy layer, thereby inhibiting the pyroly tion by Scavenging free radicals released during combustion sis process that could feed any flames. that help propagate burning, or by forming a protective non 0047. By this mode of action the amount of fuel produced flammable coating on a material. HF flame retardant materi is significantly diminished, because char rather than combus als have wide-spread applications, and provide environmen tible gas is formed. The resulting intumescent char layer plays tally-friendly products. significant roles in the flame retardant process. It acts as a 0034) Typically, flame retardants work by preventing the two-way barrier, both hindering the passage of the combus release of flammable gases from a material when heat is tible gases and molten polymer toward the flame, and shield applied. This disclosure provides retardants directed at neu ing the polymer from the heat of the flame. The amount of fuel tralizing high energy ions in a flame that can otherwise available for the fire is also significantly diminished, because decompose molecules in the material that further Sustain char, rather than combustible gas, is formed. flame, materials additives that, when exposed to heat, form a 0048 Flame Retardant Compositions. The flame retardant layer on top of the material that hinders the release of flam resin compositions described hereincan prevent the release of mable gases from the material and shields the material from flammable gases from a material, or reduce their energy, by a the flame, and material additives that release water or non variety of mechanisms. The flame retardant additive in the flammable gases upon exposure to heat. resin composition can neutralize high energy ions (e.g., H') 0035. Accordingly, the disclosure provides halogen free found in a flame, which can otherwise decompose molecules flame retardant resins that include a flame retardant material in the material into flammable gasses. The flame retardant additive. The flame retardant additives can be one or more of: additive, when exposed to heat, can also form a layer on top of US 2011/0144244 A1 Jun. 16, 2011

a solid material that hinders the release of flammable gases partially hydrogenated derivatives thereof. Such as styrene from the material and shields the material from the flame. The ethylene-butadiene-styrene copolymers, 1.2-polybutadiene, flame retardant additive can also release water or non-flam maleic anhydride-modified styrene-ethylene-butadiene-sty mable gases upon exposure to heat. The flame retardant addi rene copolymers, modified butadiene rubbers having a core tive can promote cross-linking in polymers, thereby render shell structure, and the like. ing the polymer less Susceptible to decomposition, it can 0054 Isoprene-based rubbers are typically copolymers absorb excess heat from combustible gases. The flame retar comprising isoprene as the major ingredient, which include dants described herein can act singly or in combination. styrene-isoprene block copolymers and hydrogenated or par tially hydrogenated derivatives thereof. Such as styrene-eth Synthetic Resins of the Flame Retardant Compositions. ylene-isoprene-styrene copolymers, maleic anhydride-modi 0049 Any suitable polymer or resin can be used to prepare fied styrene-ethylene-isoprene-styrene copolymers, modified the compositions and apparatuses described herein. The res isoprene rubbers having a core-shell structure, and the like. ins used in the flame retardant compositions can include 0055. In some embodiments, the polymer component or thermoplastic or thermoset polymers, and/or copolymers components of the flame retardant resin compositions thereof. Typical synthetic resins used are thermoplastic res described herein can have molecular weights of greater than ins. Examples include crystalline polyolefins such as poly about 4500. For example, one or more of the polymer com ethylene (PE), such as low-density polyethylene (LDPE), ponents can have a weight average molecular weight of very low density polyethylene (VLDPE), linear low-density 10,000 to 250,000. The polymers may optionally contain 5 to polyethylene (LLDPE), or high-density polyethylene 60 mol% of carboxyl groups or carboxylic anhydride groups. (HDPE); ethylene-vinyl acetate copolymer (EVA); ethylene The polymer component or components can include an epoxy ethyl acrylate copolymer (EEA): ethylene-methyl methacry resin, a maleimide resin, an acrylic resin, a methacrylic resin, late copolymer (EMMA); polypropylene (PP); polystyrene a diallylphthalate resin, a triazine resin, an alicyclic olefin (PS); polyacrylonitrile; acrylonitrile-butadiene-styrene polymer, an aromatic polyether polymer, a benzocyclobutene copolymer (ABS); nylon-6; and nylon-6.6. Other examples polymer, a cyanate ester polymer, and a polyimide resin can include polycarbonate (PC), polyurethane, biaxially-oriented be given. These polymers may be used either alone or in polyethylene terephthalate (boPET) polyester (e.g., Mylar(R) combinations of two or more. polyester), ethylene-C-olefin copolymer, ethylene-vinyl ester 0056. In some embodiments, the weight average molecu copolymers, ethylene-C.B-unsaturated carboxylic acid alkyl lar weight (Mw) of a polymer can be about 10,000 to 250,000, ester copolymers, poly(acrylic acid), and polyphenylene Sul or about 15,000 to 150,000, or about 20,000 to 100,000. The phone (PPS). Of course, combinations of such polymers can weight-average molecular weight of a block copolymers also be employed. used. Such as (hydrogenated) block copolymer, can also be 0050. The halogen-free flame retardant material can be about 5,000 to about 1,500,000, or about 10,000 to about blended into any resin-containing component, for example, 550,000, or about 100,000 to about 550,000, or about 100,000 components used for computers, cellular phones, personal to about 400,000. The molecular weight distribution (the ratio digital assistants, and the like. The material is especially (Mw/Mn) of the weight-average molecular weight (Mw) to useful for use in components that reside near a heat source, the number-average molecular weight (Mn)) can be about 10 Such as board materials and enclosures, for example, the or less, or about 5 or less, or about 2 or less. The Mw of the casing of a personal or laptop computer. In some embodi polymer can be measured by gel permeation chromatography ments, the resin composition has a melt flow index (ASTM (GPC) and determined as a polystyrene-reduced value. D-1238) of 0.2 to 30 g/10 min, or 0.5 to 20 g/10 min. The 0057 The HF flame retardant resin composition can be an strength of the resulting composition can be enhanced in adhesive resin composition, which may include a combina Some embodiments by employing a resin that has a melt index tion of two or more resin compounds having the same or of about 0.2 to about 10.0 g/10 min. differing molecular weights and degrees of functionality. Two 0051. In one embodiment, a single olefin resin, a combi or more resins, having the same or different functionality and nation of two or more kinds of olefin resins, or a combination molecular weights can be advantageously combined in a for of an olefin resin as a major ingredient and one or two or more mulation that results in a cured resin having a high Tg, and kinds of rubbers can be used for the resin composition. When low Dk. being used in combination, the olefin resin and rubber may be 0058. The resins used in adhesive resin compositions can combined prior to addition of a flame retardant additive, or the be heat activated and the adhesive resin compositions can flame retardant additive can be combined with major ingre have a viscosity range from about 900 to 2000 centipoise, or dient, followed by addition of the minor component resin or about 1200 to about 1700 centipoise. The viscosity can be rubber. modified by altering the Solids content or the resin ingredients 0052. The types of rubber used can include ethylene-pro used in the adhesive resin composition. pylene-based rubbers, butadiene-based rubbers, isoprene 0059 Examples of other useful resin components include based rubbers, natural rubbers, nitrile rubbers, isobutylene bistriazine resins, phenoxy resins, bis-phenol epoxy resins, rubbers, and the like. Ethylene-propylene-based rubbers phenolic novolac resins, epoxidized phenolic novolac resins, include random copolymers mainly composed of ethylene urethane resins, polyvinyl acetate resins, and any other resins and propylene, or random copolymers mainly composed of that can be useful in adhesive resin compositions. Further ethylene, propylene, and a diene monomer as the third com examples of useful resin and resin ingredients are described in ponent, such as dicyclopentadiene or ethylidene norbornene, U.S. Pat. Nos. 5,674,611; 5,629,098; and 5,874,009, which and the like. are incorporated herein by reference. 0053 Butadiene-based rubbers are typically copolymers 0060. The resin compositions typically will include about comprising butadiene as the major ingredient, which include 1 wt.% to 40 wt.%, or about 5 wt.% to 30 wt.%, of a styrene-butadiene block copolymers and hydrogenated or halogen-free flame retardant additive and from about 60 wt. US 2011/0144244 A1 Jun. 16, 2011

% to 95 wt.% of one or more resin compounds. The adhesive example, glycidyl ether epoxy compounds such as a phenol resin compositions can also include about 10 wt.% to about novolak epoxy compound, a cresol novolak epoxy com 20 wt.% of one or more halogen-free flame retardant addi pound, a cresol epoxy compound, a bisphenol A epoxy com tives, or about 12 wt.% to about 17 wt.% of a halogen-free pound, a bisphenol F epoxy compound, a brominated bisphe flame retardant additive, with the remainder being one or nol A epoxy compound, a brominated bisphenol F epoxy more resin compounds. compound, and a hydrogenated bisphenol A epoxy com 0061 The mechanical and electrical properties of the resin pound; and polyvalent epoxy compounds such as an alicyclic compositions upon cure can be substantially controlled by epoxy compound, a glycidyl ester epoxy compound, a gly choice of the molecular weight of ingredients used in the resin cidyl amine epoxy compound, and an isocyanurate epoxy composition. When certain oxygen containing resins are compound. Examples of compounds having two or more used, for example, a phenoxy resin, the molecular weight can isocyanate groups include diisocyanates and triisocyanates be about 8,000 to about 60,000, for example, about 20,000. having 6 to 24 carbon atoms. Examples of the diisocyanates 0062. The resin compositions may include other ingredi include 2,4-tolylene-diisocyanate, 2,6-tolylenediisocyanate, ents and additives known to those of ordinary skill in the art to 4,4'-diphenylmethanediisocyanate, hexamethylene-diisocy be useful in a resin composition, for example, adhesive resin anate, and p-phenylenediisocyanate. Examples of the triiso compositions. The resin compositions can be particularly cyanates include 1.3.6-hexamethylenetriisocyanate, 1.6.11 useful in preparing resin coated conductive foils, cores, and undecanetriisocyanate, and bicycloheptanetriisocyanate. other Substrates and laminates, for example, those used in the 0067 Examples of polyamine compounds include ali manufacture of printed circuitboards. The resin compositions phatic polyamine compounds having 4 to 30 carbon atoms can be used in the manufacture of resin coated conductive and two or more amino groups, aromatic polyamine com foils and, in particular, resin coated copper foils. Resin coated pounds having two or more amino groups, and the like. In copper foils can be manufactured by applying a layer of resin Some embodiments, compounds having a non-conjugated to one surface of a two surface conductive foil. The thickness nitrogen-carbon double bond Such as a guanidine compound of resin applied to the foil Surface produces a cured resin can be excluded. thickness of about 20 to about 100 microns. The resin can also 0068 Examples of aliphatic polyamine compounds be applied in a layer having a cured thickness of about 20 to include hexamethylenediamine and N,N'-dicinnamilidene-1, about 50 microns. After coating with an adhesive resin, the 6-hexanediamine. resin coated copper can be partially cured or b-staged. A 0069. Examples of aromatic polyamine compounds second layer of resin may be applied to the surface of the include 4,4'-methylenedianiline, m-phenylenediamine, 4,4'- b-staged resin layer. If a second layer of resin is applied, the diamino diphenyl ether, 4'-(m-phenylenediisopropylidene) second layer of resin can be b-staged during which time the dianiline, 4,4'-(p-phenylenediisopropylidene)dianiline, 2,2'- first layer typically becomes essentially fully cured. The final bis4-(4-aminophenoxy)phenylpropane, and 1,3,5- product can be, for example, an adhesive resin coated con benzenetriamine. ductive coated metal foil that is useful in standard printed 0070. Examples of compounds having two or more circuit board manufacturing techniques. hydrazide groups include isophthalic acid dihydrazide, 0063. In one embodiment, the HF flame retardant resin terephthalic acid dihydrazide, 2,6-naphthalenedicarboxylic composition includes a resin composition that includes a acid dihydrazide, maleic acid dihydrazide, itaconic acid dihy thermoplastic resin that includes (a) a block copolymer made drazide, trimelitic acid dihydrazide, 1,3,5-benzenetri-car up of at least two polymer blocks that include a vinyl aromatic boxylic acid dihydrazide, and pyromellitic acid dihydrazide. compound and at least one polymer block that includes a 0071 Examples of aziridine compounds include tris-2,4, conjugated diene compound and/or a hydrogenated block 6-(1-aziridinyl)-1,3,5-triazine, tris 1-(2-methyl)aziridinyl copolymer obtained by hydrogenating the block copolymer; a phosphinoxide, and hexa1-(2-methyl)aziridinyltriphospha nonaromatic-series softening agent for rubber, an ethylene triazine. C-olefin copolymer; a polypropylene resin; and one or more 0072 Examples of the peroxide include known organic flame retardant additives described below. peroxides Such as ketone peroxide, peroxyketal, hydroperoX 0064 Curing Agents. The resin of the flame retardant ide, diallylperoxide, diacylperoxide, peroxy ester, and peroxy composition can include a curing agent, for example, during dicarbonate. preparation. In a resin that is to be crosslinked, the curing 0073 Polyepoxy compounds, particularly bisphenol A agent is not particularly limited insofar as the curing agent can epoxy compounds, such as bisphenol A bis(propylene glycol crosslink the resin by heating, irradiation, or other initiative glycidyl ether) ether, are desirable various due to their mod process. In some embodiments, the curing agent is a com erate reactivity with numerous resins and their capability of pound that can form a crosslinking structure by reacting with producing composite resin molded articles that can be easily carboxyl groups of a resin. melted, processed, and laminated. 0065. Examples of curing agents include a polyepoxy 0074 The amount of curing agent used can be about 1 to compound, a compound having two or more isocyanate about 100 parts by weight, or about 5 to about 80 parts by groups, a polyamine compound, a compound having two or weight, for example, about 10 to about 50 parts by weight, for more hydrazide groups, an aziridine compound, a basic metal 100 parts by weight of the total amount of resin used in the HF oxide, an organic metal halide, and the like. These curing flame retardant resin composition. agents may be used either individually or in combinations of 0075 Curing Accelerators. A curable resin composition two or more. A peroxide such as dicumyl peroxide, octanoyl can further include a curing accelerator. A curing accelerator peroxide, m-chloroperbenzoic acid, or peracetic acid can also can facilitate obtaining a cured product having heat resis be used as a curing agent. tance. For example, when a polyepoxy compound is used as 0066 Examples of polyepoxy compounds include com the curing agent, a curing accelerator Such as a tertiary amine pounds having two or more epoxy groups in a molecule, for compound or a trifluoroboron complex can be Suitably used. US 2011/0144244 A1 Jun. 16, 2011

A tertiary amine compound is advantageous to certain sition reactions can act to form a glassy protective layer on the embodiments due to its ability to promote compositions hav material's Surface, and/or release of an acid that can cause ing significant heat resistance and chemical resistance. charring of the material, thereby reducing the release of flam Examples of tertiary amine compounds include chain-like mable gasses. tertiary amine compounds such as benzylmethylamine, tri ethanolamine, triethylamine, tributylamine, tribenzylamine, I0082. These additives can be used in relatively large con and dimethylformamide; nitrogen-containing heterocyclic centrations, and/or in combination with other types of flame compounds such as pyrazoles, pyridines, pyrazines, pyrim retardants. Specific applications of these additives, for idines, indazoles, quinolines, isoquinolines, imidazoles, and example, within organic coatings, can enable high concentra triazoles. tions to be added to resins without modifying their perfor 0076 Examples of the substituted imidazole compound mance properties. include alkyl-substituted imidazole compounds Such as I0083. The flame retardant resin compositions described 2-ethylimidazole, 2-ethyl-4-methylimidazole, bis-2-ethyl-4- herein include one or more flame retardant additives methylimidazole, 1-methyl-2-ethylimidazole, 2-isopropyl described below. The flame retardant additive can be a nitrite, imidazole, 2,4-dimethylimidazole, and 2-heptadecylimida a nitride, aborate, a silicide, a silicate, an antioxidant com Zole; and imidazole compounds substituted with a hydrocar pound, and/or combinations thereof. Examples of nitrides bon group having a cyclic structure Such as an aryl group oran include alkali metal nitrides and alkaline earth nitride. aralkyl group. Such as 2-phenylimidazole, 1-benzyl-2-meth Examples ofborates include alkali metal borates and alkaline ylimidazole, 1-benzyl-2-ethylimidazole, benzimidazole, earthborates. Examples of silicides include alkali metal sili 2-ethyl-4-methyl-1-(2-cyanoethyl)imidazole, 2-ethyl-4-me cides and alkaline earth silicides. Examples of silicates thyl-1-2'-(3".5"-diaminotriazinyl)ethyl)imidazole, and include alkali metal silicates and alkaline earth silicates. 1-benzyl-2-phenylimidazole. These curing accelerators may Examples of antioxidants include compounds such as amino be used either individually or in combination of two or more. acids (e.g., glutathione) and alkali or alkaline earth salts 0077. The amount of curing accelerator can be determined thereof, polyphenols, carotenoids, tocotrienols, ascorbic acid according to the needs of the application. Amounts typically and alkali or alkaline earth salts thereof, lipoic acid and alkali are about 0.001 to 30 parts by weight, about 0.01 to 10 parts or alkaline earth salts thereof, and/or combinations thereof. by weight, or about 0.03 to 5 parts by weight, for 100 parts by I0084. Nitrites. Nitrites (NO) can be used as flame retar weight of the total amount of resin in the composition. dant additives by incorporating the nitrites into a resin. When 0078 Fillers. The resin composition can include one or exposed to Sufficient heat, nitrite infused resins can decom more fillers. Fillers can provide the composite resin with pose to release nitrous oxide (a non-flammable gas). Alkali several desired performance characteristics such as tensile metal ions or alkaline earth metal ions can Scavenge nega strength, hardness, and/or weight. Examples of fillers include tively-charged high energy ions. Examples of nitrites that can carbon black, white carbon, silica, Zirconium silicate, alu be used as flame retardant additives include the alkali metal mina, hydrated alumina, aluminum trihydrate, hydrated mag nitrites, such as lithium nitrite (LiNO), sodium nitrite nesium, barium sulfate, barium titanate, titanium oxide, anti (NaNO), and potassium nitrite (KNO), and the alkaline mony trioxide, magnesium oxide, molybdenum oxide, tin earth metal nitrites, such as magnesium nitrite (Mg(NO)) oxide, Zinc oxide, talc, mica, glass beads, hollow glass balls, and calcium nitrite (Ca(NO)). clay, silicone oil, quartz, barium carbonate, calcium carbon 0085 Nitrides. Nitrides can act as flame retardant addi ate, and/or magnesium carbonate. tives when combined with a polymer or resin. For example, 007.9 The average particle diameter of inorganic fillers lithium nitride and the alkaline earth nitrides deprotonate can be about 0.008 um or more, but is typically less than 2 um. hydrogen gas, and are rapidly hydrolyzed by water to form In some embodiments, the diameter is about 0.01um or more, ammonia. Examples of nitrides that can be used as flame but less than about 1.5um, or 0.02 um or more, but less than retardant additives include the alkali metal nitrides, such as 1 lithium nitride (LiN), and the alkaline earth metal nitrides, 0080 Each filler is optional, but when present, each can be such as magnesium nitride (Mg,N), beryllium nitride included in about 0.1 to 30 parts by weight, or about 1 to 15 (BeN), and calcium nitride (Ca,N). parts by weight, to 100 parts by weight of the total resin I0086 Lithium nitride is readily formed and can be component. In some embodiments, more than one type of obtained commercially. NaN and KN have been synthe filler can be included in the HF flame retardant resin compo sized by simultaneously depositing metal atoms and nitrogen sition. In some embodiments, about 0.5 to 5 parts by weight of atoms onto a liquid nitrogen cooled Sapphire Substrate. Both each optional filler is included in the resin composition. NaN and KN are considered unstable compounds. 0087 Borides and Borates. Borides and/or borates can act Flame Retardant Additives. as flame retardant additives when combined with a polymer 0081. The flame retardant additives described below, or resin. The flame retardant action of the boride or borate is when combined with a resin, can result in significantly lower similar nitrides and nitrites. A negatively-charged boride or toxicity as flame retardants compared to halogen-containing borate species results upon decomposition to yield a far less flame retardants, such as chlorine and bromine containing toxic acid after it scavenges high energy protonions, in com compositions. The flame retardant additives can interfere parison to halogenated flame retardants. For example, upon with the burning process by promoting various physical pro heating near the Surface of a Solid resin material, the boron cesses. Such processes can include the release of water or containing compounds can form an acid, Such as boric acid, non-flammable gases, which dilute the gases feeding flames; which chars carbon compounds at the Surface of the resin absorption of heat energy (in these gas-release reactions), material, causing gaseous bubbles to form, which then harden thus cooling the fire; and/or production of a non-flammable within the charred Surface of the resin, producing a fire and resistant layer on the Surface of material. Such decompo resistant barrier on the surface. US 2011/0144244 A1 Jun. 16, 2011

0088. Examples of borates that can be used as flame retar 0094 Synthetic silicates also can be used in the flame dant additives include the alkali metal borates, such as sodium retardant compositions described herein. Some are called metaborate (NaBO), sodium tetraborate (NaBO7), and “hydrated silicic acid' or “wet silica”. The synthetic silicate NaBs or NaB (also known as NaBs), and the alkaline can have any crystalline structure, including somewhat ran earth metal borates, such as calcium aluminum triborate dom networks of Si-O. commonly referred to as “amor (CaAlBO7; johachidolite), and the inexpensive magnesium phous silica”. The synthetic silicate is typically 40% to 70% diboride (MgB). by weight SiO, and 5% to 45% by weight each of MgO 0089. A number of polymeric borate ions are known in and/or CaO as secondary components. In one embodiment, a anhydrous compounds, which are made by reacting B(OH) synthetic silicate containing 50% to 60% by weight of SiO, or BO with metal oxides. Examples include diborate and 12% to 30% by weight of a combination of MgO and (BOs), e.g., in Mg2BOs (suanite); triborate (B.O.), CaO, and having an ignition loss of 10 to 30% by weight is e.g., in CaAlBO, (johachidolite); tetraborate (B.O.), e.g., used. in e.g. LiBO; and metaborates containing the linear 0.095 Silicides and/or silicates act similarly to nitrites, BOI, with three coordinate boron, such as in LiBO, or with the additional ability of any remaining silicon oxide CaBO. Common borate salts include sodium metaborate compound in the resin that has not been released for high (NaBO), and sodium tetraborate (NaBO), which is usu energy ion Scavenging to form a vitreous Substance that can ally encountered as borax, the so-called decahydrate, and shield the resin from further flame exposure. actually contains the hydroxoborate ion, B.O.(OH), and is 0096 Antioxidants. Incorporation of antioxidant com often formulated NaBO(OH)4.8HO. Various other pounds such as amino acids (e.g., glutathione), polyphenols, known forms of borate can be used as flame retardant addi carotenoids, tocotrienols, ascorbic acid, and/or lipoic acid, tives, such as disodium octaborate tetrahydrate. into resins can Scavenge high energy ions that may be released 0090 Silicides. Silicides are compounds that have silicon by burning the resin. The antioxidants can be included in a bonded to more electropositive elements. Silicides are struc resin alone, or in combination with other flame retardant turally closer to borides than to carbides. The chemical bonds additives described above. in silicides range from conductive metal-like structures to 0097 Hydrates of the inorganic additives described above covalent or ionic. Silicides of all non-transition metals, with can also be employed in resins. In the presence of heat, the exception of beryllium, have been described. hydrates can decompose to release water. The water, as steam, 0091 Examples of silicides include the electrically non can form a layer of non-flammable gas near a material's conductive magnesium silicide (MgSi) and calcium silicide surface, thereby inhibiting flame formation. The reaction to (Ca,Si), and Si tetrahedra Such as KSi, Rb Si, and CSSi. release water and/or decomposition of the additive compound Silicides can also be in the form of Si chains, such as CaSi can be endothermic, thereby cooling the material and slowing chains, and corrugated hexagonal Si layers, for example, the burning process. CaSi. Group 1 and 2 silicides, e.g., Na-Si and CaSi, react 0098. The amount of the flame retardant additive used in a with water to yield hydrogen and/or silanes. Additional resin composition can be about 10 to about 300 parts by examples of alkali metal silicides and alkaline earth metal weight, for example, 100 to 250 parts by weight, to 100 parts silicides include Sodium silicide (NaSi) and magnesium sili by weight of the total resin component of the composition. cide. Magnesium silicide is dark blue or slightly purple in Amounts within the aforementioned ranges, at increments of color. Silicon dioxide forms magnesium silicide when heated 5 parts by weight, can also be used, with respect to 100 parts with magnesium. Magnesium silicide can also be formed by by weight of the total resin component of the composition. a reaction between magnesium hydride and silicon with the evolution of hydrogen gas attemperatures above 250° C. Optional Additives. 0092 Silicates. Silicate are compounds containing ions in 0099. Although the composition can include a resin, such which one or more central silicon atoms are surrounded by as a thermoplastic synthetic resin, and a flame retardant addi electronegative ligands. Silicate species most often are sili tive as described above, the flame retardant resin composition con with oxygenas the ligand. Silica, or silicon dioxide, SiO, may also include additional optional components. Inorganic can be considered a silicate, although it is the special case flame retardants, other than the flame retardant additives with no negative charge and no need for counter-ions. Silica described above, can optionally be added to resins to provide is found in nature as the mineral quartz, and its polymorphs. additional variations of the flame retardant resins described Silicon may adopt octahedral coordination by 6 oxygens, for herein. Examples of Such inorganic flame retardants include example, in the hexahydroxysilicate anion, Si(OH)', as aluminum hydroxide, magnesium hydroxide, calcium found in the mineral thaumasite (CaSiOCO)(SO4)(OH)12 hydroxide, or a combination thereof, where the particles have (HO)). an average size (diameter) of about 0.1 to about 10 um. Such 0093. Other examples of silicates include alkali metal sili inorganic compounds may be added in an amount of 1% to cates and alkaline earth metal silicates, such as the metals in 50% by weight, based on the total weight of the composition, combination with silicate ions, such as nesosilicates (SiO, to impart flame resistant effects to the resin. For example, '), e.g., olivine; Sorosilicates (SiO7]), e.g., epidote; aluminum hydroxide, magnesium hydroxide, calcium cyclosilicates (SiOs,”), e.g., the tourmaline group; ino hydroxide, or a combination thereof, can be included in about silicates (SiO”), e.g., the pyroxene group; inosilicates 1%, about 2%, about 5%, about 10%, about 15%, about 20%, (SiO, I"), e.g., the amphibole group; phyllosilicates about 30%, about 40%, or about 50% by weight, based on the (SiOs”), e.g., micas and clays; and tectosilicates (Al total weight of the composition. SiO2e), e.g., quartz, feldspars, and/or Zeolites. Tecto 0100 Other useful halogen-free fire retardant optional silicates can have additional cations when some of the silicon additives include melamine cyanurate, phosphoric acid, 1.3- is replaced by a lower-charge cation Such as aluminum. This phenylenetetraphenyl ester, di-polyoxy-ethylene, hydroxym Substitution can also take place in other types of silicates. ethylphosphonate, and mixtures thereof. The particle size of US 2011/0144244 A1 Jun. 16, 2011

optional additives such as melamine cyanurate can range 0106. In some embodiments, one or more flame retardant from about 1 to about 20 microns. Typical melamine cyanu additives as described herein can be either simply mixed into rate particle sizes are less than about 12 microns. Melamine plastics and then held in the material when the plastic sets, or cyanurate particle sizes of less than 4 microns can help mini when reactive to the plastic or optionally added crosslinking mize surface defects and resin wet-out problems. agents, the flame retardant additive can chemically bind into 0101. Other optional components include lubricants such the plastic molecules at polymerization. A selection between as mineral oil or paraffin oil, to enhance the stability of the simply mixing and chemically binding can depend on the composition, for example, during processing. The composi properties desired or required of the flame retardant resin tion may include a titanate or silane coupling agent to enhance composition, in terms of finished product performance, the adhesion of a filler to the resin matrix. The composition means of processing (e.g., melting, extrusion, and/or mold may also contain an organic or inorganic pigment or dye, Such ing), and flame retardancy characteristics (e.g., temperature as carbon black, an azo type pigment, cyanine blue, cyanine of onset of the charring process). green, iron oxide red, or titanium oxide, to add various colors 0107 Evaluation of the composition can be carried out by to the resin composition. standard polymer analysis techniques. For example, when a 0102 Yet other optional additives include antimony com thermoplastic resin other than polystyrene or ABS is used, the pounds such as antimony pentoxide, and sodium antimonite; resin, a flame retardant additive, and other additives can be inorganic compounds such as Zinc borate, guanidine Sulfa mixed and the obtained mixture can be kneaded in a 75 liter mate, Zirconium salts, molybdenum salts, aluminum borate, Banbury mixer. The mixture can be processed with a mixing and tin compounds; organometallic compounds such as fer roll to obtain a sheet having a thickness of about 3 mm. This rocene; and phosphorus-containing compounds Such as phos sheet can be reprocessed with a rectangular pelletizer to pro phates, aromatic-condensed phosphates, phosphaZene com vide a rectangular pellet having a length of each side of about pounds, phosphorus-containing epoxy compounds, reactive 3 mm. The HF flame retardant resin composition can also be phosphorus compounds, ammonium polyphosphate, provided in the form of a film or a sheet. The thickness of the melamine phosphate, melamine salts of polyphosphoric acid, film or sheet can be about 1 to 150 lum, or about 3 to 100 um, melam salts of polyphosphoric acid, melem salts of polyphos for example, about 5 to 80 um. phoric acid, complex melamine-melam-melem salts of poly 0108. This rectangular pellet can be repelletized with a phosphoric acid, red phosphorus, and phosphaZene com vent type 70 Phi extruder at 150° C. to provide a cylindrical pounds. Such components can promoting and/or provide heat pellet. This cylindrical pellet can be used as a sample for resistance, moisture resistance, and flame retardance. analysis, or it can be combined with other pellets to parts, 0103) Each optional additive, when present, can be components, or other forms for various electronic applica included in about 0.1 to 15 parts by weight, to 100 parts by tions. The cylindrical pellet can be examined for oxygen weight of the total resin component. In some embodiments, index, for example, according to JIS K-7201. The pellet can more than one optional additive, e.g., 2, 3, 4, or 5 optional also be molded into a sheet having a thickness of 200 um with additives, can be included in the HF flame retardant resin a T-die sheet molding machine to determine the combustion composition. In some embodiments, about 0.5 to 5 parts by rate of the sheet with a flammability tester, for example, weight of each additional optional additive is included in the according to FMVSS-302 standards. resin composition. 0109 When polystyrene or ABS is used as athermoplastic 0104. The resin composition can optionally exclude cer synthetic resin, the resulting composition can be molded with tain ingredients, such as one or more optional additives an injection machine of about 3.5 ounces into a test bar, for described above, Such as phosphorus or phosphorus contain example, according to the vertical flame test of UL-94. The ing compounds. The combination of certain flame retardant test bar can be further molded into a test piece having a additives and optional additives, in combination with the thickness of approximately /8 inch. This test piece can be exclusion of other optional additives can provide a composi used as a sample for the Vertical flame test. tion with excellent mechanical characteristics, fire retar 0110. The processability of the resin compositions dancy, heat resistance, and flexibility, which also exudes no described herein can be evaluated by Subjecting samples of harmful heavy metal compounds, nor does it produces a large the blend to shaping operations such as injection molding or amount of Smoke or corrosive gases when buried or burned. compression molding. For satisfactory injection molding, the material should form in the mold a homogeneous article of Preparation of Flame Retardant Resin Compositions. uniform strength. The flow viscosity characteristics of such 0105 Halogen-free fire-retardant materials secure their blends are adequate to insure filling the mold properly under fire-retardancy by mixing a halogen-free fire-retardant addi the operating conditions. In processing the resin, a lubricant tive in a resin. The halogen-free flame retardant synthetic can be included, for example, to improve the molding quality resin composition can be prepared by using a master batch of the resin composition. In some embodiments, the lubricant that includes a polymer, Such as a thermoplastic synthetic can be Akzo Armeen(R) 18D surfactant or VanfreRVam pro resin, a flame retardant additive as described herein, and other cessing aid. Any known lubricant conventionally used in plas optional additives, or by mixing these components each in tics processing can also be used. A lubricant can be used in Such an amount So as to provide its end-use concentration, amounts varying from about 0.1-3 parts by weight per 100 followed by kneading the resulting mixture by ordinary parts of the resin. In one embodiment, about 0.5-1 part by means. Such as using a single-screw type extruder, twin-screw weight per 100 parts of the resin can be used. type extruder, roll mill, or Banbury mixer. Flame retardant 0111. In the single step operation, the resin or resins, the additives, such as borates, nitrides, silicides, and/or silicates, flame retardant additive, a filler and optionally other ingredi may be preliminarily added to the other components prior to, ents can be charged at the desired ratio to a Farrell Continuous during, or after mixing the resin and other optional compo Mixer (FCM), a transfer type extruder-mixer that allows effi nentS. cient mastication of the blend at a desired temperature. The US 2011/0144244 A1 Jun. 16, 2011

blending apparatus can be pretreated to reduce the time nec phone, or similar device, and a mouse 124. For the purposes essary to reach the processing temperature range. The same of this specification, the term “computing system’ includes a operation can also be run in a Banbury-type mixer. system that uses one or more processors, microcontrollers 0112 The blend is then held at the processing temperature and/or digital signal processors and that has the capability of while continuing the mixing. During processing, a stabilizer running a “program. As used herein, the term “program system can be contacted with the blend and processing can be refers to a set of executable machine code instructions, and as continued for a short time, usually for about one minute or used herein, includes user-level applications as well as sys more, in order to thoroughly incorporate the stabilizer in the tem-directed applications or daemons, including operating blend. system and driver applications. Computing systems include 0113. In a multi-step process, the resin or resins and the communication and electronic devices, such as mobile flame retardant additive can be charged to a suitable apparatus phones (cellular or digital), music and multi-media players, wherein flame retardant additive masterbatching takes place. and Personal Digital Assistants (PDA); as well as computers, Thereafter, the flame retardant masterbatch can be blended or “computing devices of all forms (desktops, tablets, lap with the resins at desirable ratios, optionally with other com tops, servers, palmtops, workstations, etc.); and further ponents, as desired for the specific composition. include the peripheral devices that are used to control and 0114. A method for forming a non-halogen flame retar interface with the remainder of the computing system. dant resin composition includes preblending the components. I0120 Many configurations of peripheral components can One-half of the total amount of resin, Such as polypropylene, be employed with Such computing systems, as will be recog can be placed in an accurate loss and weigh feederpreblender. nized by those skilled in the art. Keyboard 108 can be of a Preweighed ingredients other than the resin can be added to configuration well-known in the industry, having plastic keys the preblender, one-half of each ingredient to each side of the and often additional components formed of plastics, includ blender. The preblender can be turned on and the resin is ing attachment cables and port connectors. As will be appar mixed for about five minutes. Thereafter, the remainder of the ent to one of skill in the art, the methods and apparatus resin is added to the preblender and mixed for about an described are applicable both to much simpler and to more additional ten minutes to thoroughly mix the resin and flame complicated devices and computing systems. Any component retardant additive system. that includes plastic or a resin can include a flame retardant 0115. An extruder resin system can be pelletized or can resin composition as described herein. conduct other processing as necessary. If pelletizing is carried I0121. In some embodiments, the input device can be a out, a pelletizer, such as a pelletizer commercially available mouse, a touch screen, a keypad of a mobile communications from Conair, Inc., can be set to, for example, about 44 rpm to device, or another type of input interface, etc. Keyboard 108 form pellets that have a diameter of for example, about can includes a plurality of keys (e.g., 112 and 114 configured 0.03125 to about 0.0625 inches (0.079 and 0.16 cm). Hot, dry to detect user inputs, and to communicate those user inputs to air can be blown over the pellets prior to packaging to mini computing device 102 through a wired (or in some cases, a mize water contact and absorption. wireless) connection 120. Mouse 124 can be configured to 0116. The flame retardant resin composition can be detect user inputs, and to communicate those user inputs to reheated to a temperature of about 410°F. (about 210°C.) for computing device 102 through a wired (or, again, in some molding various components such as casings or other Suitable cases, a wireless) connection 122. Device 118 can be config structures. The thickness of casings can be, for example, ured to detect user inputs or to allow for access of stored about 0.03125 to about 0.125 inches (0.079 and 0.32 cm). information, and to communicate those user inputs or the information to computing device 102 through a wired con Devices and Apparatuses. nection 116. The input can be communicated to the user via 0117 The flame retardant materials described herein can monitor 104. Computing device 102 can receive power be used in devices and apparatuses that include plastic mate through a power connection cord 106. rials, especially those that include electrical components or 0.122 The following Examples are intended to illustrate require flame resistance. Examples include molded parts, the above invention and should not be construed as to narrow wire coatings, circuit board Substrates, or parts for cellular its scope. One skilled in the art will readily recognize that the phones, PDAs (portable information terminals), mobile Examples Suggest many other ways in which the invention Videophones, personal computers, electronic notebooks, could be practiced. It should be understood that numerous servers, routers, LCD projectors, engineering workstations variations and modifications may be made while remaining (EWS), pagers, word processors, televisions, video recorders, within the scope of the invention. The recited amounts are calculators, a car navigation systems, POS terminals, or touch parts by weight, unless otherwise indicated. panel-equipped devices. The flame retardant materials can also be used as coverings or coatings for materials such as EXAMPLES wiring materials, electric cables, optical fibers, and the like. 0118. The resulting composite resin molded articles can Example 1 have excellent flame retardancy, electric insulation proper ties, and crack resistance, and can generate only a very small Flame-Retardant Resin Compositions amount of toxic Substances during incineration. Laminate and multilayer circuit boards can have a low thermal expan (0123. The flame retardant additive can be an alkali or sion and a high modulus of elasticity. alkaline earth nitride; an alkali or alkaline earth nitrite; an 0119 FIG. 1 illustrates a representation of computing sys alkali or alkaline earth borate; an alkali or alkaline earth tem 100 including an input device in the form of a keyboard silicide; an alkali and alkaline earth silicate; or an antioxidant 108, a device 118 that can provide input to the computing compound. For example, the flame retardant additive can be system or store information Such as an external hard drive, one or more of the following additives. US 2011/0144244 A1 Jun. 16, 2011

0124 Nitrites. The nitrite flame retardant can be lithium Example 3 nitrite (LiNO), sodium nitrite (NaNO), potassium nitrite (KNO), magnesium nitrite (Mg(NO)), or calcium nitrite (0132 (Ca(NO)). 0125 Nitrides. The nitride flame retardant can be lithium low-density polyethylene (same component as in 55 nitride, magnesium nitride (Mg,N), beryllium nitride Example 2) (BeN), or calcium nitride (Ca,N). flame retardant additive parts synthetic calcium silicate (same component as in parts 0126 Borides and Borates. The boride or borate flame Example 2) retardant can be sodium metaborate (NaBO), sodium tet raborate (NaBO), NaBas, NaBoNaBs, calcium alumi Total 103 num triborate (CaAlBO7; johachidolite), magnesium diboride (MgB), MgBOs (suanite): CaAlBO, (johachido lite); LiBO, LiBO, CaBO, Sodium metaborate Example 4 (NaBO), sodium tetraborate (NaBO7), NaBOs (OH). 8HO, or disodium octaborate tetrahydrate. 0.133 I0127 Silicides. The silicide flame retardant can be MgSi, CaSi, KSi, Rba.Si. CS Si, CaSi, Na-Si, CaSi, Sodium sili low-density polyethylene (same component as in 50 cide (Na2Si), or magnesium silicide (MgSi). Example 2) 0128 Silicates. The silicate flame retardant can be silica, flame retardant additive 50 parts silicon dioxide (SiO), thaumasite (CaSiOO)(SO4)(OH). synthetic calcium silicate (same component as in 1.5 parts 12(H2O)), olivine; or epidote. Example 2) 0129. Antioxidants. The antioxidant flame retardant can Total 101S be glutathione, Vitamin A, Vitamin E, ascorbic acid, or lipoic acid. Example 5 0134) synthetic resin 50-100 parts filler 20-150 parts flame retardant additive 25-250 parts pigment 3-30 parts low-density polyethylene (same component as in 50 Example 2) Total 98-530 parts flame retardant additive parts synthetic calcium silicate (same component as in parts Example 2) The components of Example 1 may be present at any 5 part increment from endpoint to endpoint of the recited ranges. In Total 103 Some embodiments, the filler and/or pigment components can be omitted entirely. Example 6 Examples 2-27 0135) Flame-Retardant Resin Compositions straight-chain low-density polyethylene (e.g., ULTZEX 0130 For examples 2-27, the flame retardant additive can 352OF mfcd. by Mitsui Petrochemical Industries, Ltd. MI: 2.1) be analkali or alkaline earth nitride; analkalioralkaline earth flame retardant additive 50 parts nitrite; an alkali or alkaline earthborate; an alkali or alkaline synthetic silicate (same component as in Example 2) earth silicide; an alkali and alkaline earth silicate; or an anti oxidant compound, as described for Example 1. Total 103 parts Example 2 Example 7 0131) 0.136 low-density polyethylene (e.g., YUKARON HE-30 mfcd. by 60 parts high-density polyethylene (HIZEX3300F mfd. by Mitsui Mitsubishi Petrochemical Co., Ltd., MI: 0.3) Petrochemical Industries, Ltd., MI: 0.9) flame retardant additive 40 parts flame retardant additive 50 parts synthetic calcium silicate (e.g., SILMOS-T mfcd. by 3 parts synthetic calcium silicate (e.g., SOLEX CM mfcd. by 3.0 Shiraishi Industrial Co., Ltd., SiO, content: 60%) parts Tokuyama Soda Co., Ltd., SiO, content: 57%) Total 103 parts Total 103 parts US 2011/0144244 A1 Jun. 16, 2011 11

Example 8 -continued 0137 synthetic calcium silicate (same component as in 10 parts Example 2) Total 110 parts ethylene-vinyl acetate copolymer (Evatate H 1011 mfl. by 50 parts Sumitomo Chemical Co., Ltd., vinyl acetate content: 15%) flame retardant additive synthetic calcium silicate (SOLEX CM, the same as in Example 7) Example 13 Total 103 0142

Example 9 polystyrene (e.g., STYRON 470 mfcd. by Asahi Chemical 50 parts Industry Co., Ltd, MI: 4.0) 0138 flame retardant additive 50 parts synthetic calcium silicate (SILMOS-T, same as in 3 parts Example 2) Total 103 parts polypropylene (e.g., JHG mfl. by Mitsui Toatsu Chemicals, 50 parts Inc., MI: 4.0) flame retardant additive synthetic calcium silicate (SOLEX CM, the same as in Example 7) Example 14 Total 103 0143

Example 10 ABS (e.g., DENKA OF mfcd. by Denki Kagaku Kogyo 50 parts K.K.) flame retardant additive 50 parts 0139 synthetic calcium silicate (SILMOS-T, same as in 3 parts Example 2) Total 103 parts low-density polyethylene (YUKARON HZ-30, same as that 50 parts in Example 2) flame retardant additive synthetic calcium silicate (SOLEX CM, same as in Example 7) Example 15 Total 103 0144)

Example 11 low-density polyethylene (e.g., YUKARON HE-30 mfl. by 60 parts Mitsubishi Petrochemical Co., Ltd., MI: 0.3) magnesium hydroxide (e.g., KISUMA 5B mfd. by Kyowa 40 parts 0140 Chemicals Co., Ltd., average particle size:0.8 m) synthetic calcium silicate (e.g., SILMOS-T mfcd. by 3 parts Shiraishi Industrial Co., Ltd., SiO2 content: 60%) flame retardant additive 30 parts low-density polyethylene (same component as in 50 parts Total 103 parts Example 2) flame retardant additive 50 parts synthetic calcium silicate (same component as in 7 parts Example 2) Example 16 Total 107 parts (0145

Example 12 low-density polyethylene (same component as in 55 parts Example 2) 0141 magnesium hydroxide (same component as in Example 15) 45 parts synthetic calcium silicate (same component as in 3 parts Example 2) flame retardant additive 30 parts low-density polyethylene (same component as in 50 parts flame retardant additive 30 parts Example 2) Total 103 parts flame retardant additive 50 parts US 2011/0144244 A1 Jun. 16, 2011 12

Example 17 -continued 014.6 synthetic calcium silicate (SOLEX CM, the same as in 3 parts Example 7) flame retardant additive 30 parts Total 103 parts low-density polyethylene (same component as in 50 parts Example 2) magnesium hydroxide (same component as in Example 15) 50 parts synthetic calcium silicate (same component as in 1.5 parts Example 2) Example 22 flame retardant additive 30 parts Total 101.5 parts 0151

Example 18 polypropylene (e.g., JHG mfl. by Mitsui Toatsu Chemicals, 50 parts Inc., MI: 4.0) magnesium hydroxide (same component as in Example 15) 0147 synthetic calcium silicate (SOLEX CM, the same as in Example 7) flame retardant additive 30 parts Total 103 parts low-density polyethylene (same component as in 50 parts Example 2) magnesium hydroxide (same component as in Example 15) 50 parts synthetic calcium silicate (same component as in 3 parts Example 23 Example 2) flame retardant additive 30 parts Total 103 parts 0152

Example 19 low-density polyethylene (YUKARON HZ-30, same as 50 parts that in Example 2) aluminum hydroxide (HIGILITE H-42M mfcd. by Showa 50 parts 0148 Light Metal Co., Ltd., average particle size:0.8 m) synthetic calcium silicate (SOLEX CM, same as in Example 7) flame retardant additive 30 parts straight-chain low-density polyethylene (e.g., ULTZEX 50 parts Total 103 parts 352OF mfcd. by Mitsui Petrochemical Industries, Ltd. MI: 2.1) magnesium hydroxide (same component as in Example 15) 50 parts synthetic silicate (same component as in Example 2) 3 parts Example 24 flame retardant additive 30 parts Total 103 parts 0153

Example 20 low-density polyethylene (same component as in 50 parts Example 2) 0149 magnesium hydroxide (same component as in Example 15) synthetic calcium silicate (same component as in Example 2) flame retardant additive 30 parts Total 107 parts high-density polyethylene (HIZEX 3300F mfl. by Mitsui 50 parts Petrochemical Industries, Ltd., MI: 0.9) magnesium hydroxide (same component as in Example 15) 50 parts synthetic calcium silicate (e.g., SOLEX CM mfcd. by 3.0 3 partspart Example 25 parts Tokuyama Soda Co., Ltd., SiO2 content: 57%) flame retardant additive 30 parts Total 103 parts 0154)

Example 21 low-density polyethylene (same component as in 50 parts Example 2) aluminum hydroxide (e.g., HIGILITE H-42M mfcd. by 50 parts 0150 Showa Light Metal Co., Ltd., average particle size of 0.8 m) synthetic calcium silicate (same component as in 10 parts Example 2) ethylene-vinyl acetate copolymer (Evatate H 1011 mfl. by 50 parts flame retardant additive 30 parts Sumitomo Chemical Co., Ltd., vinyl acetate content: 15%) Total 110 parts magnesium hydroxide (same component as in Example 15) 50 parts US 2011/0144244 A1 Jun. 16, 2011

Example 26 herein, for example, dicumyl peroxide or 2.5-dimethyl-2,5- di(t-butylperoxy)-hexane. The crosslinking aid can be any 0155 curing agent described herein, such as trimethylene glycol dimethylacrylate. The flame retardant additive can be any flame retardant additive, for example, one recited in Example polystyrene (e.g., STYRON 470 mfl. by Asahi Chemical 50 parts 1. The lubricant can be any lubricant described herein, such as Industry Co., Ltd, MI: 4.0) montanoic acid-Saponified ester was. magnesium hydroxide (KISUMA 5B, the same as in 50 parts Example 15) Example 35 synthetic calcium silicate (SILMOS-T, same as in 3 parts (0160 Example 2) flame retardant additive 30 parts Total 103 parts Wt. 90 INGREDIENT Net Example 27 DESIGNATION INGREDIENTNAME Weight ASO007 (BT2110) Bistriazine Resin (Mitsubishi) 39.1 0156 A50004 (PKHS-40) Phenoxy resin (40% solids - M.W. 22.4 (a) 20,000) - Used as a flexibilizer? resin ASOO15 (EPON 1031A70) Bis-Phenol-A epoxy resin 1.9 ABS (e.g., DENKA OF mfcd. by Denki Kagaku Kogyo 50 parts 981 7Q (EPN 1138MAK80) Epoxidized phenolic novolac resin 13.4 A50740 (DER 732) Epoxy resin 3.8 magnesium hydroxide (KISUMA 5B, the same as in 50 parts Flame retardant additive Halogen-free flame retardant 15.3 Example 15) as described for Example 1 synthetic calcium silicate (SILMOS-T, same as in 3 parts 97995 (PKHP-200) Solid phenoxy resin (M.W. (a) 3.1 Example 2) 20,000) flame retardant additive 30 parts Z-6040 Silane Surfactant 1.O Total 103 parts TOTALS 100 0157. In each of Examples 1-27, a second flame retardant additive can be added at an amount of about 5 parts to about Example 36 300 parts, or at any 5 part increment in between. A second 0.161. A halogen free flame retardant resin composition filler or a third retardant additive of about 1.5 parts to about 40 can include 0.5 to 15 parts by weight of a flame retardant as parts each can also be added. Each Example may also include described for Example 1: 70 to 30 parts by weight of a ther 1-30 parts of a dye or pigment component. moplastic synthetic resin; and 30 to 70 parts by weight of an inorganic filler, Such as magnesium hydroxide or aluminum Examples 28-34 hydroxide having average particle sizes of 0.1 to 10 Jum. Flame-Retardant Resin Compositions and Molded Example 36 Parts 0162. A halogen free flame retardant resin composition 0158 can include (a) 100 parts by weight of a block copolymer

Example

28 29 30 31 32 33 34 Block copolymer 100 1OO 100 1OO 1OO 100 1OO Paraffin oil 40 76 15 90 40 70 40 Ethylene-C-olefin 133 81 8O 60 1OO 370 133 copolymer Block polypropylene 33 30 33 Random polypropylene 10 10 18O Peroxide O.66 O.S4 0.4 O.S2 O.9 1.23 O.66 Crosslinking aid 2 1.6 1.2 1.56 2.7 3.7 2 Maleic acid-modified 27 21 16 21 33 46 27 LLDPE Flame retardant 500 40S 331 421 68O 924 233 additive Antioxidant (optional) 3 2.5 2.2 2.8 4.5 6.1 3 Lubricant 6 5 4.4 S.6 9.0 12.2 6

0159. The block copolymer can be any block copolymer made up of at least two polymer blocks, the polymer blocks described herein, such as SEPS. The ethylene-C.-olefin including a vinyl aromatic polymer and at least one polymer copolymer can be any ethylene-C-olefin copolymer described block that includes a conjugated diene polymer and/or a herein, such as LLDPE. The ethylene-O-olefin copolymerican hydrogenated block copolymer; (b) 30 to 70 parts by weight have a density of, for example, about 0.87 g/cm to about of a nonaromatic-series softening agent for rubber, (c) 10 to 0.925 g/cm. The peroxide can be any peroxide described 60 parts by weight of a polypropylene-series resin, (d) 50 to US 2011/0144244 A1 Jun. 16, 2011

200 parts by weight of an ethylene-C-olefin copolymer hav 3. The composition of claim 1 wherein the thermoplastic ing a density of 0.91 g/cm or less; (e) 0.1 to 1.5 parts by polymer is present in about 30 wt.% to about 70 wt.% of the weight of an organic peroxide; and 100 to 250 parts by weight composition. of a flame retardant additive, 4. The composition of claim 1 wherein the inorganic filler 0163 wherein the flame retardant additive is one, two, is one or more of carbon black, white carbon, silica, Zirco three, four, or five of: nium silicate, alumina, hydrated alumina, aluminum trihy (0164) i) lithium nitrite (LiNO), sodium nitrite (NaNO), drate, hydrated magnesium, barium Sulfate, barium titanate, potassium nitrite (KNO), magnesium nitrite (Mg(NO)), or titanium oxide, magnesium oxide, molybdenum oxide, tin calcium nitrite (Ca(NO)); oxide, Zinc oxide, talc, mica, glass beads, hollow glass balls, (0165 ii) lithium nitride, magnesium nitride (Mg,N), clay, silicone oil, quartz, barium carbonate, calcium carbon beryllium nitride (BeN), or calcium nitride (Ca,N); ate, or magnesium carbonate. 0166 iii) sodium metaborate (NaBO), sodium tetrabo 5. The composition of claim 1 wherein the inorganic filler rate (NaBO), NaBas, Na-Bo, NaBs, calcium aluminum is present in about 1 wt.% to about 30 wt.% of the compo triborate (CaAlBO7; johachidolite), magnesium diboride sition. (MgB), MgBOs (suanite): CaAlBO, (johachidolite); 6. The composition of claim 1 wherein the flame retardant LiBO: LiBO, CaBO, sodium metaborate (NaBO), additive comprises an alkali metal nitrite or an alkaline earth sodium tetraborate (NaBO), NaBO(OH)4.8HO, or metal nitrite. disodium octaborate tetrahydrate; 7. The composition of claim 6 wherein the alkali metal 0167 iv) Mg-Si, CaSi, KSi, Rb Si, Cs Si, CaSi, Na-Si, nitrite or alkaline earth metal nitrite comprises lithium nitrite, CaSi, sodium silicide (NaSi), or magnesium silicide Sodium nitrite, potassium nitrite, magnesium nitrite, or cal (Mg-Si); cium nitrite. 8. The composition of claim 1 wherein the flame retardant 0168 v) silica, silicon dioxide (SiO), thaumasite (CaSi additive comprises an alkali metal nitride oran alkaline earth (CO)(SO4)(OH)12(H2O)), olivine; or epidote; or metal nitride. 0169 vi) an amino acid, vitamin A, vitamin E, ascorbic 9. The composition of claim 8 wherein the alkali metal acid, or lipoic acid. nitride or alkaline earth metal nitride comprises lithium (0170 While specific embodiments have been described nitride, magnesium nitride, beryllium nitride, or calcium above with reference to the disclosed embodiments and nitride. examples, these embodiments and examples are only illustra 10. The composition of claim 1 wherein the flame retardant tive and do not limit the scope of the invention. Changes and additive comprises an alkali metal borate oran alkaline earth modifications can be made in accordance with ordinary skill metal borate. in the art without departing from the invention in its broader 11. The composition of claim 10 wherein the alkali metal aspects as defined in the following claims. borate or alkaline earth metal borate comprises sodium 0171 All publications, patents, and patent documents are metaborate, Sodium tetraborate, NaBas, Na-Bo, NaBs, incorporated by reference herein, as though individually calcium aluminum triborate (johachidolite), magnesium incorporated by reference. The invention has been described diboride, Suanite; johachidolite; LiBO, LiBO, CaBO; with reference to various specific and preferred embodiments sodium metaborate; sodium tetraborate; NaBOs (OH). and techniques. However, it should be understood that many 8H2O, or disodium octaborate tetrahydrate. variations and modifications may be made while remaining 12. The composition of claim 1 wherein the flame retardant within the spirit and scope of the invention. additive comprises an alkali metal silicide oran alkaline earth metal silicide. What is claimed is: 13. The composition of claim 12 wherein the alkali metal 1. A halogen free resin composition comprising: silicide or alkaline earth metal silicide comprises sodium at least one thermoplastic polymer, silicide, potassium silicide, rubidium silicide, cesium silicide an inorganic filler; and magnesium silicide, or calcium silicide. a flame retardant additive, wherein the flame retardant 14. The composition of claim 1 wherein the flame retardant additive comprises an alkali metal nitrite; an alkaline additive comprises an alkali metal silicate oran alkaline earth earth metal nitrite; an alkali metal nitride; an alkaline metal silicate. earth metal nitride; an alkali metal borate; an alkaline 15. The composition of claim 14 wherein the alkali metal earth metal borate; an alkali metal silicide; an alkaline silicate or alkaline earth metal silicate comprises thaumasite, earth metal silicide; an alkali metal silicate; an alkaline olivine; or epidote. earth metal silicate; or a combination thereof. 16. The composition of claim 1 further comprising an 2. The composition of claim 1 wherein the thermoplastic antioxidant, wherein the antioxidant comprises an amino polymer comprises one or more of polyethylene (PE); ethyl acid, vitamin A, vitamin E, ascorbic acid, or lipoic acid. ene-vinyl acetate copolymer (EVA); ethylene-ethyl acrylate 17. The composition of claim 1 wherein composition has a copolymer (EEA): ethylene-methyl methacrylate copolymer melt index of 0.1 g/10 minto 10.0 g/10 min. (EMMA); polypropylene (PP); polystyrene (PS); polyacry 18. A halogen free resin composition comprising: lonitrile; acrylonitrile-butadiene-styrene copolymer (ABS); 70 parts to 30 parts by weight of at least one thermoplastic nylon-6: nylon-6,6; polycarbonate (PC); polyurethane; biaxi polymer, ally-oriented polyethylene terephthalate (boPET) polyester; 30 parts to 70 parts by weight of an inorganic filler; and ethylene-C-olefin copolymer, ethylene-vinyl ester copoly 0.5 parts to 15 parts by weight of a flame retardant additive, mers; ethylene-C.B-unsaturated carboxylic acid alkyl ester wherein the flame retardant additive comprises an alkali copolymers; poly(acrylic acid); or polyphenylene Sulphone metal nitrite; an alkaline earth metal nitrite; an alkali (PPS). metal nitride; an alkaline earth metal nitride; an alkali US 2011/0144244 A1 Jun. 16, 2011 15

metal borate; an alkaline earth metal borate; an alkali at least one thermoplastic polymer; metal silicide; an alkaline earth metal silicide; an alkali an inorganic filler, and metal silicate; an alkaline earth metal silicate; or a com- a flame retardant additive, wherein the flame retardant bination thereof. additive comprises an alkali metal nitrite; an alkaline 19. A computing system, input device, or computer com- earth metal nitrite; an alkali metal nitride; an alkaline ponent comprising the composition of claim 1. earth metal nitride; an alkali metal borate; an alkaline 20. A computing system, comprising: earth metal borate; an alkali metal silicide; an alkaline at least one component selected from the group consisting earth metal silicide; an alkali metal silicate; an alkaline essentially of a housing, an input device, and a cable, earth metal silicate; or a combination thereof. wherein the component comprises a halogen free resin, that includes, ck c. : : :