HK1113934B - Coated compressible substrates - Google Patents

Description

Coated compressible substrates

Technical Field

The present invention relates to coated compressible substrates. More particularly, the present invention relates to compressible materials coated with an aqueous polyurethane coating comprising an aqueous polyurethane resin having a hydroxyl number of less than 10, and a colorant.

Background

Conventional methods of adding color to polyolefin foams, such as Ethylene Vinyl Acetate (EVA) foams, typically require the addition of an in-mold colorant before or during the casting stage. Such pigmented foams typically require dispersion of the colorant throughout the foam.

In the footwear industry, midsoles may be formed of compressible foam. Manufacturers often desire the use of colored soles and/or midsoles to enhance the overall appearance of the footwear. Each sole or midsole is often produced by adding a colorant prior to or during the casting stage of the foam. To utilize a colored foam sole or midsole, shoe manufacturers typically need to create and stock large repositories of soles and midsoles of various colors and sizes, depending on the specifications of each product. This can create significant inventory difficulties and/or manufacturing costs.

It is desirable to apply a colored coating to compressible substrates, thereby reducing the need to maintain an inventory of these substrates. Thus, there remains a need for compressible materials coated with colored coatings that provide adequate mechanical and/or appearance properties.

Summary of The Invention

Embodiments of the present invention provide an article comprising a compressible substrate and a coating on at least a portion of the compressible substrate, the coating comprising an aqueous polyurethane resin having a hydroxyl number of less than 10 and a colorant.

Another embodiment of the present invention provides a compressible substrate comprising a coating on at least a portion of the substrate, the coating comprising an aqueous polyurethane resin having a hydroxyl number of less than 10 and a colorant.

Another embodiment of the present invention provides a method of coating a compressible substrate comprising applying to at least a portion of the compressible substrate a coating composition comprising an aqueous polyurethane resin having a hydroxyl number of less than 10 and a colorant.

Yet another embodiment of the present invention provides a footwear component comprising a foam substrate, the exterior surface of the component being at least partially coated with a coating comprising a colorant.

These and other embodiments of the present invention will become more apparent from the following description.

Detailed Description

The present invention provides a compressible substrate coated with a coating comprising an aqueous polyurethane dispersion and a colorant. It has been observed that the coatings of the present invention can be substantially flexible such that flaking, peeling and/or cracking of the coating is minimized when the coated substrate is compressed, folded, bent and/or bent.

The term "compressible substrate" as used herein means a substrate that is capable of undergoing compressive deformation and returning to substantially the same shape once the compressive deformation ceases. The term "compressive deformation" as used herein refers to a mechanical stress that reduces the volume of the substrate in at least one direction (at least temporarily). The compressible substrate can be coated with the coating of the present invention on any number of exterior surfaces. The coating can be applied to substantially all of the exterior surface, or any portion of any number of exterior surfaces. In certain embodiments, substantially all, i.e., 90% or more, such as 95% or more, of the outer surface is coated according to the present invention; thus, these embodiments differ from foams decorated with logos, patterns, etc., the relatively small areas of the outer surface of the latter being decorated, typically in a predetermined pattern. For example, substantially all of the outer surface exposed in the finished article of manufacture can be coated in accordance with the present invention.

The term "coating" as used herein refers to a material that forms a substantially continuous layer or film on a substrate. The coating can be applied to the compressible substrate to any desired thickness, such as a thickness suitable to achieve the desired mechanical properties and/or visual effect. In one non-limiting embodiment, the coating can penetrate into a portion of the surface of the compressible substrate, such as into the pores of the open-cell foam on the outer surface of the compressible substrate, while retaining the coating on the outer surface of the compressible substrate.

For some applications, it may be desirable to apply at least one coating directly to the outer surface of the compressible substrate. In other applications, it may be desirable to apply a primer to the exterior of the compressible surface prior to applying any coating. Examples of primers include epoxies, epoxy polyamides, polyolefins, chlorinated polyolefins, vinyl polymers, polyurethanes, alkyds, acrylics, and/or polyesters, and the like. In other applications, a protective layer such as a sealant layer can be applied to the outer surface of the coating. The sealant can provide a protective and/or visually pleasing layer, such as a clear coat.

The coating can be applied as a single coating or as one layer in a multi-layer coating system having two or more layers, wherein each coating may or may not contain different components. It will be appreciated that the coating of the present invention is sprayed onto the substrate itself, which may or may not have other coatings already applied thereto, and that the coating of the present invention is not applied as a laminate, nor to release paper and transfer to the substrate. Therefore, the present invention can reduce labor time.

In one embodiment of the invention, the coating composition is substantially solvent-free. The term "substantially solvent-free" as used herein means that the coating composition contains less than about 15 or 20 weight percent organic solvent, preferably less than 5 or 10 weight percent organic solvent, wherein the weight percentages are based on the total weight of the coating composition applied to the substrate. For example, the coating composition may contain from zero to 2 or 3 wt% of an organic solvent.

As used herein, the term "aqueous" refers to coating compositions wherein the carrier liquid of the composition is predominantly water, i.e., greater than 50 weight percent of the carrier comprises water. The remainder of the support comprises less than 50 wt% organic solvent, typically less than 25 wt%, preferably less than 15 wt%. Water may comprise from about 20 to about 80 wt%, typically from about 30 to about 70 wt%, of the total composition, based on the total weight of the coating composition (including the carrier and solids).

The coating used according to the invention comprises a polyurethane dispersion. Any polyurethane resin that forms a suitable film and is compatible with the aqueous composition can be used according to the present invention without compatibility issues. Suitable polyurethane resins include those formed from polyisocyanates, active hydrogen-containing materials such as polyols, polyethers, polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polyamines, polyolefins, silicone polyols and/or mixtures thereof, acid-functional materials having functional groups reactive with isocyanates and optionally polyamines. Examples of acid functional materials include dimethylpropionic acid and butyric acid. Some examples of resins suitable for use in the coating compositions of the present invention are described in U.S. Pat. No.5,939,491, which is incorporated herein by reference.

In one non-limiting embodiment, the polyurethane has an average molecular weight of at least 10,000, such as at least 25,000, such as 100,000 or more. In certain embodiments the polyurethane resin has a hydroxyl number of less than about 10, such as less than about 5, such as less than about 3. The film-forming polyurethane resin is generally present in the coating in an amount greater than about 20 wt%, such as greater than about 40 wt%, and less than 90 wt%, where wt% is based on the total solids weight of the cured coating. For example, the wt% of resin can be between 20-80 wt%.

In one non-limiting embodiment, di-and/or tri-functional acrylic resins, polyesters, polyethers, polycarbonates, polyamides, epoxies, and/or vinyl resins can be added as a partial replacement for a portion of the polyurethane dispersion. Suitable di-and/or tri-functional acrylic resins can include copolymers of unsaturated acrylic monomers and/or vinyl monomers prepared by emulsion polymerization. Suitable polyester resins can include the reaction products of polyfunctional acid anhydrides, polyfunctional alcohols, and monofunctional acids and alcohols. Other suitable resins include hybrids or mixtures of any of these resins, for example, acrylic/polyurethane and/or acrylic/polyester hybrids and/or blends.

The coating of the present invention also includes a colorant. The term "colorant" as used herein refers to any substance that imparts color and/or other opacity and/or other visual effect to the composition. The colorant can be added to the coating in any suitable form, such as discrete particles, dispersions, solutions, and/or platelets. A single colorant or a mixture of two or more colorants can be used in the coating of the present invention.

Examples of colorants include pigments, dyes, and toners, such as those used in the paint industry and/or listed in the Dry Color Manufacturers Association (DCMA), as well as special effect compositions. The colorant may comprise, for example, a finely divided solid powder that is insoluble but wettable under the conditions of use. The colorant can be organic or inorganic and can be agglomerated or non-agglomerated.

Examples of pigments and/or pigment compositions include, but are not limited to, carbazole dioxazine crude pigment, azo, monoazo, disazo, naphthol AS, salt types (lakes), benzimidazolone, condensates, metal complexes, isoindolinone, isoindoline and polycyclic phthalocyanine, quinacridone, perylene, perinone, diketopyrrolopyrrole, thioindigo, anthraquinone, indanthrone, anthrapyrimidine, flavanthrone, pyranthrone, anthanthrone, dioxazine, triarylcarbocation, quinophthalone pigments, diketopyrrolopyrrole red ("DPPBO red"), titanium dioxide, carbon black and mixtures thereof. The terms pigment and colored filler can be used interchangeably.

Examples of dyes include, but are not limited to, those that are solvent and/or aqueous, such as phthalein (pthalo) green or blue, iron oxide, bismuth vanadate, anthraquinone, perylene, aluminum, and quinacridone.

Examples of hueing agents include, but are not limited to, pigments dispersed in an aqueous or water-miscible carrier, such as AQUA-CHEM 896 commercially available from Degussa, Inc., CHARISMA COLORANTS and MAXITORNER INDUSTRIAL COLORANTS commercially available from Accurate Dispersions division of Eastman Chemical, Inc.

As noted above, the colorant can be in the form of a dispersion, including, but not limited to, a nanoparticle dispersion. The nanoparticle dispersion can include one or more highly dispersed nanoparticle colorants or colorant particles that produce a desired visible color and/or opacity and/or visual effect. The nanoparticle dispersion can include a colorant, such as a pigment or dye having a particle size of less than about 150nm, such as less than 70nm, or less than 30 nm. Nanoparticles can be produced by milling a starting organic or inorganic pigment with milling media having a particle size of less than 0.5 mm. Examples of nanoparticle dispersions and methods for making them are disclosed in U.S. patent application publication No.2003/0125417, which is incorporated herein by reference. Nanoparticle dispersions can also be produced by crystallization, precipitation, gas phase condensation, and chemical milling (i.e., partial dissolution). To minimize reagglomeration of nanoparticles within the coating, a dispersion of resin-coated nanoparticles may be used. As used herein, "dispersion of resin-coated nanoparticles" refers to a continuous phase in which are dispersed discrete "composite microparticles" comprising nanoparticles and a resin coating on the nanoparticles. Examples of dispersions of resin-coated nanoparticles and methods for making them are disclosed in U.S. application Ser. No.10/876,315, filed 24, 6-2004, which is incorporated herein by reference, and U.S. provisional application No.60/482167, filed 24, 6-2003, which is also incorporated herein by reference.

Examples of special effect compositions that can be used in the coatings of the present invention include pigments and/or compositions that produce one or more appearance effects such as reflectance, pearlescence, metallic luster, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, goniochromism and/or color change. Additional special effect compositions can provide other perceptible properties, such as opacity or texture. In a non-limiting embodiment, the special effect composition is capable of producing a color shift such that the color of the coating changes when the coating is viewed at different angles. Examples of color effect compositions are disclosed in U.S. patent application publication No.2003/0125416, which is incorporated herein by reference. Other color effect compositions can include transparent coated mica and/or synthetic mica, coated silica, coated alumina, transparent liquid crystal pigments, liquid crystal coatings, and/or any composition having interference resulting from refractive index differences within the material and not due to refractive index differences between the surface of the material and air.

In certain non-limiting embodiments, a photosensitive composition and/or photochromic composition (which reversibly changes its color when exposed to one or more light sources) can be used in the coatings of the present invention. Photochromic and/or photosensitive compositions can be activated by exposure to radiation of a specified wavelength. When the composition is excited, the molecular structure changes and the altered structure exhibits a new color that is different from the original color of the composition. When the exposure to radiation is eliminated, the photochromic and/or photosensitive composition is able to return to a resting (rest) state, wherein the original color of the composition is restored. In one non-limiting embodiment, the photochromic and/or photosensitive composition is capable of being colorless in a non-excited state and exhibiting color in an excited state. Full color changes can occur within milliseconds to minutes, such as from 20 seconds to 60 seconds. Examples of photochromic and/or photosensitive compositions include photochromic dyes.

In non-limiting embodiments, the photosensitive composition and/or photochromic composition can be associated with and/or at least partially bonded to (e.g., using covalent bonds) the polymer and/or polymeric material of the polymerizable component. In contrast to some coatings in which the photosensitive composition migrates out of the coating and crystallizes into the substrate, according to a non-limiting embodiment of the present invention, the photosensitive composition and/or photochromic composition associated with and/or at least partially bonded to the polymer and/or polymerizable component has minimal migration out of the coating. Examples of photosensitive compositions and/or photochromic compositions and methods for making them are disclosed in U.S. patent application Ser. No.10/892,919, filed on 7/16/2004 and incorporated herein by reference.

In general, the colorant can be present in the coating composition in any amount sufficient to impart the desired visible and/or color effect. The colorant may comprise from 1 to 65 weight percent, such as from 3 to 40 weight percent or from 5 to 35 weight percent of the composition of the present invention, wherein the weight percent is based on the total weight of the composition.

The coating composition of the present invention also optionally includes other ingredients such as crosslinkers, extenders, Ultraviolet (UV) absorbers, light stabilizers, plasticizers, surfactants, leveling agents, adhesion promoters, rheology modifiers, Hindered Amine Light Stabilizers (HALS), and wetting agents in a total amount of up to 80 weight percent, based on the total weight solids of the coating composition applied to the substrate. Suitable crosslinking agents include carbodiimides, aziridines (azidines), melamines, bisoxazolidines, acid-catalyzed formaldehyde, and/or isocyanates. Water-based carbodiimides are preferred in some applications because they do not provide a significant amount of organic solvent for the coating composition. When a crosslinker is used, it is generally present in an amount up to about 50 weight percent, based on the total solids weight of the cured coating.

Other optional coating additives include odor-effect compositions that introduce desirable odors to the coating and/or limit the generation of undesirable odors over time. Examples of odor effect compositions can include fragrance additives, such as fragrances and/or colognes, and/or odor masking compositions, such as deodorizers. In a non-limiting embodiment, the odor effect composition can include an additive that generates or emits the odor of new leather.

Other suitable coating components include one or more texture enhancing agents that improve the surface feel of the coating and/or enhance the stain resistance of the coating. In one non-limiting embodiment, the texture enhancer imparts a soft feel to the coating. The term "soft touch" as used herein means that the coated substrate exhibits altered tactile properties such as simulated velvet or leather feel when touched. The texture enhancer can be an additive added to the coating composition, such as a silica matting agent and/or a wax additive. Examples of silica matting agents can include ACEMATT OK 412 and ACEMATT TS 100 commercially available from Degussa, Inc. Examples of wax additives can include polytetraethylene oxide, fluorinated waxes, polyethylene waxes, or natural waxes such as paraffin and/or carnauba wax. In another non-limiting embodiment, the texture enhancer can be incorporated into the polyurethane resin itself. For example, components that provide a larger "soft segment" for the polyurethane can be used. Examples include polytetramethylene ether glycol commercially available from Invista, Inc under the name TERATHANE 2000.

Examples of compressible substrates include foam substrates, liquid-filled polymer bladders, air and/or gas-filled polymer bladders, and/or plasma (plasma) filled polymer bladders. The term "foam substrate" as used herein refers to a polymeric or natural material that includes open cell foams and/or closed cell foams. As used herein, the term "open cell foam" refers to a foam comprising a plurality of interconnected cells. The term "closed cell foam" as used herein means that the foam comprises a series of discrete closed cells. Examples of foam substrates include polystyrene foam, polymethacrylimide foam, polyvinyl chloride foam, polyurethane foam, polypropylene foam, polyethylene foam, and polyolefin foam. Examples of polyolefin foams include polypropylene foams, polyethylene foams, and/or Ethylene Vinyl Acetate (EVA) foams. The EVA foam can comprise a flat sheet or block or a molded EVA form, such as a midsole. Different types of EVA foam can have different types of surface porosity. Molded EVA can include a dense surface or "skin" while flat sheets or blocks can exhibit a porous surface.

The coating of the present invention can be applied to a compressible substrate by any conventional coating application. Examples of coating application methods include spraying, slot coating, roll coating, curtain coating, dip coating, screen printing, brush coating, or bar coating. In some embodiments, the coating is applied to substantially all of the entire outer surface of the compressible substrate. In other embodiments, the coating is applied to a portion of the outer surface of the compressible substrate.

In one non-limiting embodiment, the article includes any article or article of manufacture that includes a compressible substrate. In non-limiting embodiments, the article can comprise a shoe and/or a shoe component. The term "shoe" as used herein includes shoes, including athletic shoes, men and women's formal shoes, men and women's casual shoes, children's shoes, sandals, including flip-flops (flip-flops), boots, including work boots, outdoor shoes, orthopedic shoes, slippers, and the like. As used herein, the term "shoe component" includes any part or portion of a shoe that includes a compressible substrate. Examples of footwear components include soles, midsoles, toppers, and linings. The midsole and sole can include ethylene vinyl acetate foam.

Unless expressly stated otherwise, all numbers such as those expressing values, ranges, amounts or percentages used herein may be read as modified by the word "about", even if the term is not expressly stated. Any numerical range recited herein is intended to include all sub-ranges subsumed therein. As used herein, the singular and plural referents of "a", "an", and "the". Thus, although the present invention has been described with respect to "an" aqueous polyurethane and "a" colorant, one or more aqueous polyurethanes and/or colorants can be used. Similarly, any number or combination of the other components described herein can be used in accordance with the present invention. The term "polymer" as used herein refers to prepolymers, oligomers and both homopolymers and copolymers; the prefix "poly" refers to two or more.

Examples

The following examples are intended to illustrate various aspects of the invention and are not intended to limit the scope of the disclosure or claims.

Example 1

Sample coatings 1-7 were prepared by mixing the components shown in table 1.

TABLE 1

	Sample 1(g)	Sample 2(g)	Sample 3(g)	Sample 4(g)	Sample 5(g)	Sample 6(g)	Sample 7(g)
								Polyurethane Dispersion 1	81.75	-	-	-	-	-	-
Polyurethane Dispersion 2	-	83.27	69.49	53.33	52.41	56.31	59.75
								Carbodiimide crosslinking agent1	14.60	16.03	18.87	14.47	14.23	14.37	15.25
Polyurethane Dispersion 3	0.50	0.70	-	-	-	-	-
								Defoaming agent2	0.25	0.70	-	-	-	-	-
White toner3	-	-	-	26.20	15.14	-	-
								Blue toner4	-	-	-	-	6.09	-	-
Green toner5	-	-	-	-	0.64	-	-
								Red toner6	-	-	-	-	-	23.56	25.00
Black toner7	-	-	-	-	-	-	-
								Solvent(s)8	1.00	-	-	-	-	-	-
Deionized water	1.90	-	11.64	6.00	11.29	5.76	-
								Equivalent ratio of PU to crosslinking agent	1.0∶1.0	1.0∶1.0	1.0∶1.0	1.0∶1.0	1.0∶1.0	1.0∶1.0	1.0∶1.0

¹CARBODILITE V02-L2, commercially available from Nisshinbo Chemicals

²Air Products MD-20 defoaming agent

³OneSource, 9292-T1467 white toner, available from PPG Industries, Inc

⁴OneSource, 9292-L8843 blue toner, available from PPG Industries, Inc

⁵OneSource, 9292-G9463 Green toner, available from PPG Industries, Inc

⁶OneSource, 9292-R3817 Red toner, available from PPG Industries, Inc

⁷OneSource, 9292-B3546 Lamp Black toner, available from PPG Industries, Inc

⁸DOWANOL PM, available from Dow Chemical from PPG Industries, Inc

Polyurethane Dispersion 1

Polyurethane dispersion 1 was prepared by charging 1010.3g of polytetramethylene ether glycol (sold under the name TERATHANE 2000) and 50.7g of dimethylolpropionic acid in a reaction vessel equipped with a stirrer, thermocouple, condenser and nitrogen inlet and heating to 60 ℃. 336.7g of isophorone diisocyanate were added over 10 minutes, followed by 356.2g of methyl ethyl ketone and 1.51g of dibutyltin dilaurate. The reaction exothermed to 63 ℃. The reaction temperature was increased to 80 ℃ and the contents were stirred until the isocyanate equivalent weight was 1380. 39.4g dimethylolpropionic acid was then added to the reaction flask. The contents were stirred until the isocyanate equivalent weight was 2094.

The product obtained had a solids content of 83.4% by weight (measured at 110 ℃ C. for 1 hour), an acid number of 21.20mg KOH/g and a weight-average molecular weight of 14971 (measured in THF).

1552.0g of the above prepolymer at 76 ℃ was added over 25 minutes to a solution consisting of 2259.9g of deionized water, 40.6g of adipic dihydrazide and 52.2g of dimethylethanolamine stirred at 21 ℃ and 500rpm in a cylindrical gallon reaction flask equipped with a baffle, a double pitched blade paddle stirrer, a thermocouple and a condenser. The dispersion temperature after addition was 36 ℃. The reaction contents were stirred until the absence of isocyanate was observed by FTIR.

The dispersion was transferred to a flask equipped with a stirrer, thermocouple, condenser and receiver. The dispersion was heated to 60 ℃ and then the methyl ethyl ketone and water were removed by vacuum distillation.

The final dispersion had a solids content of 38.7 wt% (measured after 1 hour at 110 ℃), a Brookfield viscosity of 144 centipoise (using #2 spindle, 60rpm), an acid content of 0.171 milliequivalents acid/g, a base content of 0.177 milliequivalents base/g, a pH of 8.26, a residual methyl ethyl ketone content of 0.15 wt%, and a weight average molecular weight of 95536 (measured in DMF).

Polyurethane Dispersion 2

Polyurethane dispersion 2 was prepared by charging 1447.3g of polytetramethylene ether glycol (molecular weight about 1,000, sold under the name TERATHANE 1000), 145.4g of dimethylolpropionic acid and heating to 60 ℃ in a reaction vessel equipped with a stirrer, thermocouple, condenser and nitrogen inlet. 965.3g of isophorone diisocyanate were added over 13 minutes, followed by 637.5g of methyl ethyl ketone and 4.34g of dibutyltin dilaurate. The reaction exothermed to 72 ℃. The reaction temperature was increased to 80 ℃ and the contents were stirred until the isocyanate equivalent weight was 923.5. 114.0g dimethylolpropionic acid was then added to the reaction flask. The contents were stirred until the isocyanate equivalent weight was 1430.2.

1512.2g of the above prepolymer at 75 ℃ was added over a period of 16 minutes to a solution consisting of 2201.9g of deionized water, 58g of adipic dihydrazide and 76.2g of dimethylethanolamine stirred at 25 ℃ and 515rpm in a cylindrical gallon reaction flask equipped with baffles, a double pitched blade paddle stirrer, a thermocouple and a condenser. The dispersion temperature after addition was 40 ℃. The reaction contents were stirred until the absence of isocyanate was observed by FTIR. The dispersion was transferred to a flask equipped with a stirrer, thermocouple, condenser and receiver. The dispersion was heated to 50 ℃ and then the methyl ethyl ketone and water were removed by vacuum distillation.

The final polyurethane dispersion had a solids content of 37.48 wt% (measured after 1 hour at 110 ℃), a Brookfield viscosity of 1450 cps (using #3 spindle, 60rpm), an acid content of 0.240 milliequivalents acid/g, a base content of 0.247 milliequivalents base/g, a residual methyl ethyl ketone content of 1.16 wt%, and a weight average molecular weight of 77274 (measured in DMF).

Polyurethane Dispersion 3

Polyurethane dispersion 3 was produced by sequentially adding and mixing the following ingredients: 35 parts by weight of DISPERCOLL E585 polyurethane resin, which has 40% by weight of an ion-dispersed polyurethane resin in water, commercially available from Bayer Corporation; 16 parts by weight of a RHOPLEX VA 2113 polyvinyl acetate latex having 55% by weight in water of a polyvinyl acetate latex commercially available from Rohm and Haas; 7 parts by weight of PLASTHALL BSA butyl benzenesulfonamide plasticizer, commercially available from The c.p. hall company; 1 part by weight XAMA2 trimethylolpropane tris- (B- (N-aziridinyl) propionate), commercially available from Virginia Chemicals; 2 parts by weight of carbodiimide; 1 part by weight of propylene glycol; and 0.5 parts by weight of RHOPLEX QR 708 thickener, commercially available from Rohm and Haas.

Samples 1-7 were prepared in the following manner. The polyurethane dispersion 1 or 2 was stirred by using a pneumatic rotary air stirrer and a low-blade impeller. The additives were added sequentially with stirring in the amounts of the additives specified in table 1. The mixture was filtered through an 18TXX polyester multifilament screen into a clean container. The resulting coating was allowed to equilibrate for approximately 24 hours prior to application.

Samples 1 and 2, designated in Table 1, were sprayed onto EVA foam using a DEVILBISS SRI-625 HVLP gravity hand spray gun at 29psi inlet pressure/10 psi air cap. The coatings were applied to a dry film thickness of 10-50 microns. Spray-coated onto the EVA foam at 40psi using a Binks Model 7 suction feed gun. The EVA foam coated with samples 1 and 2 was flashed at ambient temperature for 10 minutes and then cured at 140 ° f for 10 minutes. The EVA foam coated with samples 5-block (slab), 6 and 7 was flashed for 10 minutes at ambient temperature and then cured for 5 minutes at 180 ° f. The EVA foam-molded midsole coated with sample 5 flashed at ambient temperature for 20 minutes and then cured at 180 ° f for 5 minutes.

The coated EVA foam was then tested for initial adhesion according to ASTM standard D3359. Adhesion was measured on a scale of 1-5, where 1 is the complete loss of adhesion and 5 is no loss of adhesion. The coating was also applied to EVA foam and placed in a calibrated humidity chamber at 100% relative humidity and 100 ° f for 10 days according to ASTM standard D2247-99. The coated foam was removed from the humidity chamber and tested for post wet adhesion according to ASTM D3359. Post wet adhesion was measured on the same 1-5 scale. The coated foam was also tested for post wet lather according to ASTM standard D714. Post-wet lather was measured on a scale of 0-10 with frequency of dense lather (D), Medium Dense (MD), medium (M), less (F), little (VF), and no (N). The 0-10 scale refers to the size of the blister, where 10 is no blister, 9 is a blister visible with a microscope, 8 is a blister visible with the naked eye, and then as the number approaches 0, the blister becomes progressively larger.

The coating was also applied to EVA foam and manually bent at a 180 ° angle in the front-to-back direction for approximately 1 minute. To visually assess changes in appearance, including the severity of the cracking. The results of the above tests are shown in table 2.

TABLE 2

Paint sample	EVA foam type	InitialAdhesion Property	Post wet adhesion	Post-wet frothing	Flexibility
						Sample 1	Sheet	5	5	8VF	Without visible coating cracking, loss of adhesion or change in appearance
Sample 2	Sheet	5	4	8VF	Without visible coating cracking, loss of adhesion or change in appearance
						Sample No.5	Sheet	5	-	-	Without visible coating cracking, loss of adhesion or change in appearance
Sample No.5	Middle sole of moulded shoes	5	-	-	Without visible coating cracking, loss of adhesion or change in appearance
						Sample No.6	Middle sole of moulded shoes	5	-	-	Without visible coating cracking, loss of adhesion or change in appearance
Sample 7	Middle sole of moulded shoes	5	5	-	Without visible coating cracking, loss of adhesion or change in appearance

Example 2

Commercially available flip-flops made from EVA foam were partially coated with samples 1, 2, 3 and 4 of example 1; a portion of the flip-flops were coated with the sample coating and the remaining portion was uncoated. The flip-flops coated with sample 1 exhibited a "soft touch" tactile performance when touched.

Flip-flops coated with samples 1, 3 and 4 were tested experimentally by wearing them for up to 6-7 hours per day for two consecutive weeks. In each case, the portion of the flip-flop coated with the sample coating was significantly cleaner than the uncoated portion. Less dirt adhered to the portion of the flip-flop coated with the sample coating than to the uncoated portion. The various parts of the flip-flop coated with samples 3 and 4 did not show any loss of adhesion and the coating maintained its integrity after passing through, however, in some areas a series of micro-cracks with dimensions below 2mm were produced. The various parts of the flip-flop coated with sample 1 did not show any loss of adhesion, maintaining the coating integrity and no visible micro-cracking.

Example 3

Portions of the commercially available finished DADA shoe were masked with tape. The EVA foam was then rinsed in isopropanol and the coating of sample 4 was sprayed using a DEVILBISS spray gun according to the procedure of example 1 and then cured at 140 ° f for 10 minutes to a dry film thickness of 1-2 mils. These shoes were subjected to experimental tests by putting them on for a period of 3 months starting from summer, almost every day for the whole day. The various parts of the shoe coated with the coating of sample 4 were visually cleaner than the uncoated parts. The coating maintains adhesion and coating integrity.

After three months of fitting, one shoe was put into a standard household washing machine and washed with laundry detergent. The washed shoe also maintains the integrity of the coating and adhesion in the coated portion. The coated portions of the washed shoes were visually cleaner than the coated portions of the unwashed shoes.

Example 4

The EVA foam coated with the coating of sample 7 was sent to a shoe factory where it was introduced into a prototype shoe. In this example, the coating of sample 7 was applied directly to the EVA foam substrate using a DEVILBISS spray gun and then cured at 140 ° f for 10 minutes. The coated EVA foam withstood the rigors of the shoemaking process but did not show any visible loss of adhesion, loss of coating integrity, cracking or peeling.

Example 5

The previously uncoated EVA midsoles of two DADA shoes were coated with two different formulations of a polyurethane dispersion containing a toner. The first formulation was produced by adding 10g of aluminum mill base to a premix of 73g of polyurethane dispersion 2 and 17g of carbodiimide under slow agitation.

A second formulation was produced by adding 50g of the blue nanopigment dispersed polyurethane acrylic colorant to a premix of 37.0g of polyurethane dispersion 2 and 9.0g of carbodiimide. A pre-emulsion was prepared by stirring charge a1 specified in table 3 on a stainless steel beaker with a Cowles impeller to produce an acrylic resin colorant having a blue nanopigment dispersed therein. The pre-emulsion was then circulated through MICROFLUIDIZER 110T at 8,000psi for 15 minutes and then transferred to a four-necked round bottom flask equipped with an overhead stirrer, condenser, electronic temperature probe, and nitrogen atmosphere. Charge B, specified in table 3, was used to rinse the microfluoridizer and added to the flask. The temperature of the microemulsion was adjusted to 30 ℃. The polymerization was initiated by adding charge C as specified in Table 3 followed by 30 minutes of charge D, also specified in Table 3. The temperature of the reaction was increased to 56 ℃. The final pH of the latex was 7.24, the nonvolatile content was 35.9%, and the Brookfield viscosity was 87 cps.

TABLE 3

¹The pigment dispersion was prepared by mixing 45.0g of an acrylic resin²473.0g deionized water, 45.0g phthalein (phthalo) blue (2% solids weight), and 1800.0g Glass beads having an average diameter of 71 microns commercially available from Potters Glass, Inc. The mixture was milled at 5,000rpm for 6 hours. The progress of the milling was monitored by measuring the visible spectrum of the sample and observing the decrease in the absorbance at a wavelength of 400 nm. During the milling process, 200g of make-up water was added as needed to compensate for the increase in viscosity of the mixture. The mixture was filtered through a1 micron felt bag (felt bag) to remove glass beads. The product had a nonvolatile content of 7.58%.

²The acrylic resin is prepared by mixing acrylic resin with air stirrer and thermoelectricity20.0g of magnesium acid silicate and 120.0g of toluene were mixed in a 2-liter flask of a coupled azeotropic distillation apparatus. The mixture was heated to reflux and azeotropically removed of water. The mixture was then cooled and placed under a nitrogen atmosphere, and 7.5g of 2, 2' -bipyridine and 6.1g of copper (0) powder were added to the mixture while maintaining the nitrogen atmosphere. 30.4g of p-toluenesulfonyl chloride were also added to the mixture while maintaining the nitrogen atmosphere. 169.2g of benzyl methacrylate and 20.0g of glycidyl isopropyl ether were added to the addition funnel, which was then purged with nitrogen for 15 minutes prior to addition. 169.2g of benzyl methacrylate and 20.0g of glycidyl isopropyl ether were then added to the reaction flask and the mixture carefully heated to 70 ℃. When the solids content reached 60.7%, 888.3g of MPEG (550) MA and 250.0g of toluene were added to the addition funnel and purged with nitrogen for 15 minutes. 888.3g of MPEG (550) MA and 250.0g of toluene were then added to the reaction over 30 minutes, while maintaining a reaction temperature of 70 ℃. The reaction was heated for 6 hours, then cooled, and stirred overnight in a nitrogen blanket. The reaction mixture was diluted with 500g of toluene and then filtered through a cake of magnesium acid silicate to remove residual catalyst. The solvent was removed under vacuum to give a resin at 98.4% solids.

³The polyurethane/urea prepolymer was produced in a four-necked round bottom flask equipped with an electronic temperature probe, mechanical stirrer, condenser, and heating mantle. 269.8g N-methyl-pyrrolidone, 91.1g of hydroxyethyl methacrylate (HEMA), 234.7g of dimethylolpropionic acid (DMPA), 2.2g of triphenyl phosphite, 2.2g of dibutyltin dilaurate and 2.2g of butylated hydroxytoluene were stirred in a flask at a temperature of 100 ℃ until all the solids were dissolved. 700.0g of poly (butylene oxide) having a number average molecular weight of 1000 was added, and the mixture was cooled to 70 ℃.1,100.4 g of 4, 4' -methylenebis (cyclohexyl isocyanate) were added over a period of 15 minutes. The addition funnel containing the isocyanate was rinsed with 481.8g of butyl methacrylate and the temperature of the mixture was held at 90 ℃ for another 3 hours. 642.5g of butyl acrylate were added over a period of ten minutes. The resulting composition was designated as charge A. In a separate flask, 4,263.3g of water, 124.7g of dimethylEthanolamine, 73.6g diethanolamine and 42.1g ethylenediamine were heated to 60 ℃. The resulting composition was designated as charge B. Charge A was added to charge B and the resulting mixture was cooled to room temperature. The final product was a white emulsion having an acid number of 15.2, a Brookfield viscosity of 800 cps, a pH of 7.37, and a non-volatile content of 28.4%.

Each of these formulations was sprayed onto EVA foam midsoles using a DEVILBISS spray gun (as described in example 2), then cured at 140 ° f for 10 minutes and evaluated to determine adhesion and blistering. As shown in table 4, the results obtained are excellent, although sagging is a problem, thereby initiating rheological property optimization.

TABLE 4

Formulation	Shoe base material	Initial adhesion	After 10 days wet adhesion/blistering
				Aluminum color-adjusting paste preparation	EVA foam sheet	5	5/10
Polyurethane acrylic resin dispersed with blue nanopigment	EVA foam sheet	5	5/10

Example 6

A coating composition was prepared by mixing 47.49g of polyurethane dispersion 2 with 12.40g of CARBODILITE V02-L2, and 40.11g of photochromic urethane acrylate in a beaker. Photochromic urethane acrylates were produced by adding the ingredients shown in table 5 in the order described to a four-necked round bottom flask equipped with an electronic temperature probe, mechanical stirrer, condenser and heating mantle.

TABLE 5

¹Blue photochromic dye 3, 3-bis (4-methoxyphenyl) -6, 11, 13-trimethyl-13- (2- (2- (2-hydroxyethoxy) ethoxy) -3H, 13H-indeno [2, 1-f)]Naphtho [1, 2-b ]]Pyrans

²2-heptyl-3, 4-bis (9-isocyanato) -1-pentyl-cyclohexane

³2- (dihexanolide) ethyl acrylate

Charge a was stirred in the flask and then heated to a temperature of 90 ℃ for 30 minutes. Charge B was added to the mixture, and the mixture was held at 90 ℃ for 60 minutes. Charges C and D were added and the mixture was held at 90 ℃ for 30 minutes. Photochromic urethane acrylates are dark blue liquids with a non-volatile content of 53.4%, measured at 110 ℃ for one hour.

The final composition was blended with low-lift blades attached to an air-driven rotating stirrer. The polyurethane dispersion and carbodiimide were blended in a ratio of 40: 60. Mixing was carried out at low to moderate speed for 5 minutes. The mixture was filtered through an 18TXX polyester multifilament mesh into a clean container.

The coating composition was spray coated onto the EVA foam substrate as described in example 2. The coated substrate showed good adhesion and acceptable fade-back when the applied light source was removed from the coating.

Although specific embodiments of the invention have been described above for purposes of illustration, it will be appreciated by those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.

Claims (44)

1. An article of manufacture, comprising:

a compressible substrate comprising a foam substrate; and

a coating comprising an aqueous polyurethane resin having a hydroxyl number of less than 10 and a colorant on at least a portion of the compressible substrate.

2. The article of claim 1 wherein the hydroxyl number is less than 5.

3. The article of claim 1, wherein the polyurethane has a molecular weight of at least 10,000.

4. The article of claim 1, wherein the coating is substantially solvent-free.

5. The article of claim 1 wherein said colorant comprises a special effect composition that produces one or more appearance effects selected from the group consisting of reflectance, pearlescence, metallic sheen, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, goniochromism, color change, opacity, or texture.

6. The article of claim 5, wherein the special effect composition comprises a photosensitive composition and/or a photochromic composition.

7. The article of claim 6 wherein the photosensitive composition and/or photochromic composition is combined with a polymer and/or polymeric material of a polymerizable component.

8. The article of claim 6, wherein the photosensitive composition and/or photochromic composition is at least partially bonded to a polymer and/or polymeric material of the polymerizable component.

9. The article of claim 1, wherein the colorant comprises transparent coated mica and/or synthetic mica, coated silica, coated alumina, a transparent liquid crystal pigment, or a liquid crystal coating.

10. The article of claim 1, wherein the coating further comprises a texture enhancer.

11. The article of claim 1, wherein the coating further comprises a carbodiimide crosslinker.

12. The article of claim 1, wherein the coating further comprises an odor effect composition.

13. The article of claim 1, wherein the compressible substrate comprises an open cell and/or closed cell foam.

14. The article of claim 1, wherein the compressible substrate comprises an olefin foam.

15. The article of claim 14, wherein the compressible substrate comprises an ethylene vinyl acetate copolymer foam.

16. The article of claim 1, wherein the article is a shoe and/or shoe component.

17. The article of claim 1, wherein the colorant is in the form of a nanoparticle dispersion.

18. The article of claim 1, wherein the coating is applied to substantially all of the outer surface of the compressible substrate, said outer surface being the exposed surface in the finished article of manufacture.

19. A compressible substrate comprising a coating on at least a portion of the substrate, the coating comprising an aqueous polyurethane resin having a hydroxyl number of less than 10 and a colorant, the compressible substrate comprising a foam substrate.

20. The compressible substrate of claim 19, wherein the polyurethane has a molecular weight of at least 10,000.

21. The compressible substrate of claim 19 wherein the coating is substantially solvent free.

22. The compressible substrate of claim 19, wherein the colorant comprises a special effect composition that produces one or more appearance effects selected from the group consisting of reflectance, pearlescence, metallic sheen, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, goniochromism, color change, opacity, or texture.

23. The compressible substrate of claim 22 wherein the special effect composition comprises a photosensitive composition and/or a photochromic composition.

24. The compressible substrate of claim 19 wherein the colorant comprises transparent coated mica and/or synthetic mica, coated silica, coated alumina, a transparent liquid crystal pigment or a liquid crystal coating.

25. The compressible substrate of claim 19 wherein the coating further comprises a texture enhancer.

26. The compressible substrate of claim 19 wherein the coating further comprises a carbodiimide crosslinking agent.

27. The compressible substrate of claim 19 wherein the coating further comprises an odor effect composition.

28. The compressible substrate of claim 19, wherein the compressible substrate comprises an open cell and/or closed cell foam.

29. The compressible substrate of claim 19, wherein the compressible substrate comprises an olefin foam.

30. The compressible substrate of claim 29, wherein the olefin foam comprises an ethylene vinyl acetate copolymer foam.

31. The compressible substrate of claim 19, wherein the compressible substrate is a shoe component.

32. The compressible substrate of claim 19 wherein the colorant is in the form of a dispersion of nanoparticles.

33. The compressible substrate of claim 19 wherein the coating is applied to substantially all of the outer surface of the compressible substrate, said outer surface being the exposed surface in the finished article of manufacture.

34. A method of coating a compressible substrate comprising applying a coating composition comprising an aqueous polyurethane resin having a hydroxyl number of less than 10 and a colorant to at least a portion of a compressible substrate, said compressible substrate comprising a foam substrate.

35. The method of claim 34, further comprising applying a primer layer directly to the outer surface of the compressible substrate prior to applying the coating composition.

36. The method of claim 34, further comprising applying a protective layer over at least a portion of the coating composition.

37. The method of claim 34, wherein the compressible substrate comprises an open cell and/or closed cell foam.

38. A footwear component comprising a foam substrate, wherein an outer surface of the component is at least partially coated with a colorant-containing coating comprising an aqueous polyurethane resin having a hydroxyl number of less than 10.

39. The footwear component of claim 38, wherein the coating comprises a polyurethane dispersion.

40. The footwear component of claim 38, wherein the coating is substantially solvent-free.

41. The footwear component of claim 38, wherein the foam substrate comprises an olefin foam.

42. The footwear component of claim 41, wherein the olefin foam comprises ethylene vinyl acetate.

43. The footwear component of claim 38, wherein the colorant is in the form of a dispersion of nanoparticles.

44. The shoe component of claim 38, wherein the coating is applied to substantially all of the exterior surface that will be exposed when the shoe component is assembled into a shoe.