US 2003O152774A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2003/0152774 A1 Cradic et al. (43) Pub. Date: Aug. 14, 2003 (54) COLORED DATA STORAGE MEDIA Related U.S. Application Data (63) Continuation of application No. 09/766,303, filed on (76) Inventors: Curtis Cradic, Newburgh, IN (US); Jan. 19, 2001. Steven R. Peak, Evansville, IN (US); Connie J. Bland, Mt. Vernon, IN (US); Publication Classification Steven F. Hubbard, West Sand Lake, (51) Int. Cl. ................................................. B32B 27/36 NY (US) (52) U.S. Cl. .............................................................. 428/412 Correspondence Address: (57) ABSTRACT CANTOR COLBURN, LLP 55 GRIFFINROAD SOUTH One method for producing a data Storage media, comprises: BLOOMFIELD, CT 06002 molding a material comprising plastic and a fluorescent material to form a Substrate, and disposing a data layer on the Substrate. The Substrate has a transmissivity of about (21) Appl. No.: 10/249,071 85% or less at a readback laser wavelength when traversing a 1.2 mm thick colored Substrate, and the has a fluorescent color emission wavelength which is not equal to the read (22) Filed: Mar. 13, 2003 back laser wavelength. US 2003/0152774 A1 Aug. 14, 2003 COLORED DATA STORAGE MEDIA SUMMARY OF INVENTION CROSS REFERENCE TO RELATED 0008. The colored data storage media overcomes the above described drawbacks and deficiencies. One method APPLICATIONS for producing a data Storage media, comprises: molding a 0001. This application is a continuation of U.S. applica material comprising plastic and a fluorescent material to tion Ser. No. 09/766,303, filed on Jan. 19, 2001, which form a Substrate, and disposing a data layer on the Substrate. claims the benefit of the filing date of U.S. Provisional The substrate has a transmissivity of about 85% or less at a Application Serial No. 60/166,135, filed on Sep. 29, 2000, readback laser wavelength when traversing a 1.2 mm thick which is hereby incorporated by reference. colored Substrate, and the has a fluorescent color emission wavelength which is not equal to the readback laser wave BACKGROUND OF INVENTION length. 0002 Optical, magnetic and magneto-optic media are primary Sources of high performance Storage technology 0009. Another method for producing a data storage media which enables high Storage capacity coupled with a reason comprises: molding a material comprising plastic and colo able price per megabyte of Storage. Use of optical media has rant to form a Substrate, wherein the Substrate has a trans become widespread in audio, Video, and computer data missivity of about 70% to about 85% at a readback laser applications in Such formats as compact disk (CD), digital wavelength when traversing a 1.2 mm thick colored Sub versatile disk (DVD) including multi-layer structures like Strate, and disposing a data layer on the Substrate. DVD-5, DVD-9, and multi-sided formats such as DVD-10, 0010 Yet another method for producing the data storage and DVD-18, magneto-optical disk (MO), and other write media, comprises: molding a material comprising plastic, once and rewritable formats such as CD-R, CD-RW, DVD and a fluorescent material to form a SubStrate, wherein the R, DVD-RW, DVD+RW, DVD-RAM. In these and other substrate has a transmissivity of about 85% or less at a formats, data are encoded onto a Substrate into a digital data readback laser wavelength when traversing a 1.2 mm thick Series. In pre-recorded media, Such as CD, the data are colored Substrate, and wherein the Substrate has a fluorescent typically pits and grooves formed on the Surface of a plastic color emission wavelength which is not equal to the read Substrate through a method Such as injection molding, back laser wavelength and has a transmissivity of about 70% Stamping or the like. to about 90% at the laser readback wavelength, and dispos 0003. In recordable and rewritable media, the data are ing a data layer on the Substrate. encoded by laser, which illuminates an active data layer that 0011) Another method for producing data storage media, undergoes a phase change, thus producing a Series of highly comprises: molding a material comprising plastic, colorant, reflecting or non-reflective regions making up the data and Visual effects to form a Substrate, and disposing a data Stream. In these formats, a laser beam first travels through a layer on the Substrate. The Substrate has a transmissivity of plastic Substrate before reaching the data layer. At the data about 85% or less at a readback laser wavelength when layer, the beam is either reflected or not, in accordance with traversing a 1.2 mm thick colored Substrate, and the Visual the endcoded data. The laser light then travels back through effects are Selected from the group consisting of glass, metal, the plastic and into an optical detector System where the data titanium dioxide, mica, angular metamerism materials, and are interpreted. combinations comprising at least one of the foregoing visual 0004. It is well known in the art that, due to the sensitivity effects. of the optical readout System, the amount of absorption of DETAILED DESCRIPTION the light by the media should be minimized. Consequently, the plastic in the optical media is a colorless, transparent 0012. The present invention relates to data storage media, material having good birefringence properties, Such as poly namely, colored optical data Storage media and methods for carbonate. Although media formats have been introduced making the Same. In one embodiment, the colored media which read data from the top-side of a Substrate, the vast has, at the readback laser wavelength, a transmissivity of majority of playback Systems are only compatible with light of about 85% or less, with about 70% to about 85% media requiring the laser to travel through the Substrate preferred, about 75% to about 80% also preferred, and about twice. Hence, the transparency to the laser is a requirement 75% to about 85% especially preferred, when traversing a and colorless materials are typically used to maximize 1.2 mm thick colored substrate (disk). Alternatively, if transparency at the laser wavelength. fluorescent, the media preferably emits light at a wavelength which does not inhibit data retrieval. The fluorescent media 0005 The widespread use of colorless, transparent mate can comprise a Substrate which has a transmissivity, at the rials makes product differentiation difficult, except by costly readback laser wavelength, of about 85% or less, preferably printing methods on the top Surface of the optical media. exceeding 68%, with about 70% to about 95% preferred, Furthermore, in the cases where printed decorations cover about 70% to about 90% more preferred, and about 70% to one entire Surface of a disk, the covered Surface is unusable about 85% especially preferred, when traversing a 1.2 mm for data Storage. thick substrate (disk). 0006 What is needed in the art are colored plastic 0013 Typically, these storage media can comprise a compositions for use as optical media. Substrate comprising a plastic and a colorant which does not inhibit data retrieval. Generally, up to about 10 weight TECHNICAL FIELD percent (wt %) colorant can be used, with up to about 5 wt 0007. The present disclosure relates to data storage % preferred, up to about 1 wt % colorant more preferred, and media, and especially relates to fluorescent, plastic data less than about 0.5 wt % or so colorant especially preferred, Storage media. based upon the total weight of the Substrate. US 2003/0152774 A1 Aug. 14, 2003 0.014. In theory, any plastic that exhibits appropriate mineral filled Silicone, bis-maleimides, cyanate esters, Vinyl, properties and can be employed. However, the plastic should and benzocyclobutene resins, in addition to blends, copoly be capable of withstanding the Subsequent processing mers, mixtures, reaction products and composites compris parameters (e.g., application of Subsequent layers) Such as ing at least one of the foregoing plastics. Sputtering (i.e., temperatures up to and exceeding about 200 C. (typically up to or exceeding about 300° C.) for magnetic 0017 AS used herein, the terms “polycarbonate”, “poly media, and temperatures of about room temperature (about carbonate composition', and “composition comprising aro 25° C) up to about 150° C. for magneto-optic media). That matic carbonate chain units” includes compositions having is, it is desirable for the plastic to have sufficient thermal structural units of the formula (I): Stability to prevent deformation during the deposition StepS. 0018) For magnetic media, appropriate plastics include thermo plastics with glass transition temperatures greater than about 150° C., with greater than about 200° C. preferred (e.g., (I) polyetherimides, polyetheretherketones, poly Sulfones, poly O etherSulfones, polyetheretherSulfones, polyphenylene ethers, polyimides, high heat polycarbonates, etc.); with -R-O-L-o- materials having glass transition temperatures greater than about 250 C. more preferred, such as polyetherimide in 0019 in which at least about 60 percent of the total which sulfonedianiline or oxydianiline has been substituted number of R groups are aromatic organic radicals and the for m-phenylenediamine, among others, as well as polyim balance thereof are aliphatic, alicyclic, or aromatic radicals. ides, Such as Probimide (or the dry powder equivalent, Matrimid 5218, from Ciba Geigy Chemical); combinations 0020 Preferably, R is an aromatic organic radical and, comprising at least one of the foregoing plastics, and others. more preferably, a radical of the formula (II): 0.015 Additionally, it is possible for thermosets to be -A-Y-A*- (II) used in the application provided the thermoset possess Sufficient flow under the Stamping conditions to permit 0021) wherein each of A' and A is a monocyclic divalent formation of the desired Surface features. AS Various appli aryl radical and Y is a bridging radical having one or two cations may require polymers with different glass transition atoms which separate A' from A.