United States Patent (19) 11 Patent Number: 5,744,542 Martz Et Al
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USOO5744542A United States Patent (19) 11 Patent Number: 5,744,542 Martz et al. 45 Date of Patent: Apr. 28, 1998 54 EMULSFERS AND THER USE IN WATER 5, 191012 3/1993 Markusch et al. ...................... 524/59 DSPERSIBLE POLY SOCYANATE 5, 1944.87 3/1993 Jacobs ............... ... 524/840 COMPOSITIONS 5,200,489 4/1993 Jacobs et al. 528/49 5202,377 4/1993 Thorne et al. .......................... 524,591 5,252,696 10/1993 Laas et al. ........ ........ 528/49 75 Inventors: Jonathan T. Martz, Shaler Township, 5296,160 3/1994 Tirpak et al. ..... ... 252/82.2 Allegheny County; Joseph M. Carney, 5,300,556 4/1994 Tirpak et al. .......................... 524/591 Reserve Township, Allegheny County; 5,331,039 7/1994 Blum et al. ....... ... 524/SO Robert E. Jennings, New Sewickley 5,373,050 12/1994 Morikawa et al. ..................... 524,591 Township, Beaver County; Karen D. 5,380,792 l/1995 Renk ....................................... 524840 Donnelly, Hampton Township, 5,387,367 2/1995 Haeberde et al. 252/182,22 Allegheny County, all of Pa. 5,389,718 2/1995 Potter et al. ............................ 524,591 5,389,720 2/1995 Markusch et al. ...................... 524,839 73 Assignee: PPG Industries, Inc., Pittsburgh, Pa. FOREIGN PATENT DOCUMENTS 21 Appl. No.: 744,566 20854.95 6/1993 Canada. 2088805 8/1993 Canada. 22 Filed: Nov. 6, 1996 63-2 16070 12/1989 Japan. 1-2 16070 4/1991 Japan. Related U.S. Application Data OTHER PUBLICATIONS 63 Continuation of Ser. No. 411253, Mar. 27, 1995, aban doned. Isocyanates, Organic; Encyclopedia of Chemical Technol ogy, vol. 13, pp. 789-817. 51 int. Cl. .................. C08 3/00; C08K 3/20; CO8L 75/00; CO7C 261/00 Primary Examiner-Patrick D. Niland 52 U.S. C. ......................... 524A590; 524/507; 524/539; Attorney, Agent, or Firm-Dennis G. Millman; Paul S. 524/591; 524/839; 524/840; 525/123: 525/131: Chirgott 525/455; 528/44; 560/26; 560/115 57 ABSTRACT 58 Field of Search .................................... 524/507,539, 524/591, 839, 840, 590; 525/123, 131, An aqueous two-component polyisocyanate coating compo 455; 528/44; 560/26, 115 sition is based on an essentially isocyanate-free emulsifier that comprises the reaction product of: 56) References Cited (i) an isocyanate and U.S. PATENT DOCUMENTS (ii) a member selected from the group consisting of: hydroxy functional polyalkyl ethers containing at least 3,996.154 12/1976 Johnson et al. ......... ... 252/312 4,433,095 2/1984 Hombach et al. ...... ... 524/563 five ethylene oxide, alcohols different from said poly 4,436,862 3/1984 Tetenbaum et al. ... ... 524,445 alkyl ethers, amine compounds, and combinations 4,446,256 5/1984 Hicks .................. ... 523/402 thereof. The hydroxy functional polyalkyl ether is 4,472,550 9/1984 Reiff et al. .......... ... S24/589 provided in a quantity sufficient to react at least one 4,663,377 5/1987 Hombach et al. ...... ... S24/196 equivalent of isocyanate groups in polyisocyanate (i), 4,798,745 1/1989 Martz et al. ........... 525/2O7 and the total amounts of reactants (ii) are sufficient to 4,798,746 1/1989 Claar et al. ..... ... 421407 react all of the isocyanate groups of the polyisocyanate 4,870,15 9/1989 Schol et al. 528/49 (i). 5,043,381 8/1991 Coogan et al. ... 524,591 5,075,370 12/1991 Kubitza et al. ... 524/591 5,182,355 1/1993 Martz et al. ....................... ... 528/75 29 Claims, No Drawings 5,744.542 1 2 EMULSFERS AND THER USE IN WATER Therefore, there is a need for polyisocyanate based emul DSPERSIBLE POLYSOCYANATE sifiers that contain substantially no isocyanate-reactive COMPOSITIONS groups, preferably none, in order to readily disperse the aqueous, two-component, isocyanate-reactive coatings in This application is a continuation of application Ser. No. 5 water while maintaining the superior performance properties 08/411,253 filed Mar, 27, 1995 now abandoned. of these coatings. It would also be beneficial if a wide range of polyisocyanates could be employed in the preparation of FIELD OF THE INVENTION the emulsifier. This invention relates to emulsifiers, their preparation and use in water dispersible polyisocyanate compositions. and to O SUMMARY OF THE INVENTION aqueous, two-component coating compositions incorporat One aspect of the present invention is an emulsifier that ing the water dispersible polyisocyanate compositions and comprises the reaction product of: emulsifiers in combination with an aqueous, polymeric resin (i) an isocyanate and having isocyanate-reactive groups. 5 (ii) a member selected from the group consisting of: BACKGROUND OF THE INVENTION hydroxy functional polyalkyl ethers containing at least five ethylene oxide groups, alcohols different from said The use of water based coatings, as opposed to solvent polyalkyl ethers, amine compounds, and combinations based coatings, has become increasingly more important due thereof. The hydroxy functional polyalkyl ether is to environmental considerations. However, in the case of provided in a quantity sufficient to react at least one isocyanate-reactive coatings, the presence of water presents 20 equivalent of isocyanate groups in polyisocyanate (i), a problem in that the isocyanate groups react not only with and the total amounts of reactants (ii) are sufficient to the isocyanate-reactive groups with which they are intended react all of the isocyanate groups of the isocyanate (i), to react, but also with the water as well. In order to overcome i.e., at least 99 percent of the isocyanate groups origi this disadvantage, the prior art has made use of emulsifiers nally present in the isocyanate component (i). The that are the reaction product of polyisocyanates and hydroxy 25 isocyanate composition (i) is preferably a polyisocy functional polyethers such that the emulsifier retains latent anate. isocyanate functionality to assist in the crosslinking reaction The present invention is also includes an aqueous poly of the coating and sufficient hydrophilic character to keep isocyanate composition, as well as an aqueous two the coating composition dispersed in an aqueous medium. component coating. The polyisocyanate composition (I) U.S. Pat. No. 3,996,154 discloses emulsion of an aromatic comprises a polyisocyanate (a) and the substantially polyisocyanate in water using an isocyanate functional, isocyanate-free emulsifier (b) described above, wherein that non-ionic surface active agent containing oxyethylene the emulsifier (b) is present in an amount of from 5 to 75. groups. U.S. Pat. No. 4472,550 provides for similar emul preferably 15 to 40, percent by weight based on the resin sions that are useful as binders, where the isocyanate func 35 solids weight of (a) plus (b). The aqueous two-component tional emulsifier is based on a variety of polyisocyanates. coating composition comprises the polyisocyanate compo U.S. Pat. Nos. 4,665,377 and 5.296.160 disclose polyisocy sition (I) and an aqueous polymer resin (II) that contains anate compositions suitable for dispersion in water, which isocyanate-reactive groups, wherein the components (I) and contain isocyanate functional emulsifiers. U.S. Pat. No. (II) are present in an amount sufficient to provide an equiva 5,200.489 is directed to a polyisocyanate composition that is lent ratio of isocyanate groups to isocyanate-reactive groups dispersible in water with an average isocyanate functionality of about 0.5:1 to 5:1, preferably 0.8:1 to 2:1. The isocyanate of 2 to 6 prepared by reacting a 16-hexamethylene diiso reactive groups are preferably hydroxyl groups and/or amine cyanate based polyisocyanate adduct and an emulsifier groups. based on the polyisocyanate adduct or another polyisocy DETALED DESCRIPTION OF THE anate and a monohydroxy functional polyether, such that the 45 polyisocyanate composition in combination with an INVENTON isocyanate-reactive aqueous polymer resin provides a coat The emulsifiers of the present invention are the reaction ing composition. U.S. Pat. No. 5.252,696 relates to the product of an isocyanate and a hydroxy functional polyalkyl composition and preparation of water-dispersible polyiso ether. Any organic isocyanate may be used, and suitable cyanate mixtures having an average isocyanate functionality 50 isocyanates would include known aliphatic, cycloaliphatic, of 1.8 to 4.2 and containing cycloaliphatically bound iso aromatic and heterocyclic isocyanates. Examples of suitable cyanate and ethylene oxide groups. isocyanates for preparing the emulsifier include phenyl The use of isocyanate functional materials often requires isocyanate, octyl isocyanate, p-butyl phenyl isocyanate, o that precautions be taken with respect to handling and use and p-methoxy isocyanate, o-isocyanate benzyl chloride. based on sensitization and toxicity considerations. Such 55 cyclohexyl isocyanate, octyl isocyanate, octadecyl precautions can be relatively burdensome when the coating isocyanate, and chlorohexyl isocyanate. Preferred are poly compositions are utilized under controlled factory isocyanates such as ethylene diisocyanate, 1,4- conditions, for example, manufacturing of automobiles. tetramethylene diisocyanate, 1.6-hexamethylene diisocyan Automotive refinishing coatings, however, tend to be ate (HDI), 2,4,4-tri-methyl-1,6-hexamethylene applied under conditions that are not nearly as controlled as diisocyanate, 1,12-dodecane diisocyanate, cyclobutane-1,3- in automobile plants. diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1, In addition, the synthesis and production of novel isocy 4-diisocyanate, 1-isocyanato-2-isocyanatomethyl anate compounds and compositions has come under strict cyclopentane, 1-isocyanato-3,3,5-trimethyl-5- regulation by governmental agencies, and therefore it is isocyanatomethyl cyclohexane (isophorone diisocyanate or increasingly difficult to obtain clearance for manufacture of 65 IPDI), 2.4-hexahydrotoluylene diisocyanate, 2.6 new materials, especially those that fall into the categories -hexahydrotoluylene diisocyanate, 2,4'-dicyclohexylhexyl of compounds including isocyanates. methane diisocyanate, 4,4'-dicyclohexylmethane 5,744.542 3 4 diisocyanate, 1.3-phenylene diisocyanate, 14-phenylene mixture is heated to obtain a homogeneous mixture at diisocyanate, 2.4-toluylene diisocyanate (TDI), 2,6- temperatures of about 60° C.