HK1158245B - Biomass derived radiation curable liquid coatings - Google Patents

Description

Biomass-derived radiation-curable liquid coatings

Technical Field

The present invention relates to radiation curable liquid coatings comprising the reaction product of a polyol and a polycarboxylic acid/anhydride, wherein at least some of the polyol and/or the polycarboxylic acid/anhydride is derived from biomass.

Background

The prices of raw materials used in many manufacturing processes continue to rise, particularly as their prices rise or fall with the price of crude oil. For this reason, and because of the prediction of depletion of oil reserves, raw materials derived from renewable resources or alternative resources are desirable. The increased demand for environmentally friendly products, along with the change and instability of the petrochemical market, has prompted the development of raw materials from renewable and/or inexpensive sources. This increased demand has led to the interest in biodegradable coating compositions in a number of industries. This is particularly relevant in the consumer electronics industry, where an increasing number of cellular phones, PDAs, MP3, etc. seek to achieve landfills. Biodegradable coatings, particularly biodegradable housings, are desirable. In addition, UV curable coatings are often needed in various industries, particularly those in which it is desirable not to subject the substrate to thermal curing. Examples again include the consumer electronics industry, certain segments of the automotive industry, the plastics industry, and the wood industry.

Disclosure of Invention

The present invention relates to a radiation curable liquid coating comprising: a) a polyol; and b) a polycarboxylic acid/anhydride, wherein at least some of a) and/or b) is derived from biomass, wherein the polyol is not a condensation reaction product of an acid functional compound and a hydroxy functional compound, wherein the reaction product contains ethylenic unsaturation derived from a) and/or b), but if derived solely from b, then b has more than four carbons.

Detailed Description

The present invention relates to radiation curable liquid coatings comprising the reaction product of a polyol and a polycarboxylic acid/anhydride, wherein at least some of the polyol and/or the polycarboxylic acid/anhydride is derived from biomass. This reaction product is sometimes referred to by the terms "polyol/polycarboxylic acid reaction product", "reaction product", and the like; the term "polyol/polycarboxylic acid reaction product" is also used broadly herein to refer to the product resulting from the reaction of the polyol/polycarboxylic acid reaction product with one or more other components. The polyol/polycarboxylic acid reaction product itself contains ethylenic unsaturation, which is known to those skilled in the art as a radiation curable moiety, thereby rendering the coating radiation curable. As used herein, the term "derived from biomass" is understood to be derived from living or recently living organisms such as plants (including trees) or animals as well as sources not derived from petroleum based sources.

Any suitable polyol may be used in accordance with the present invention. One skilled in the art will appreciate that polyols are compounds having two or more hydroxyl groups. Suitable polyols may include, but are not limited to, small molecules containing more than one hydroxyl group, such as neopentyl glycol, glycerol, isosorbide, pentaerythritol, and/or propylene glycol, or polymeric polyols such as polyester polyols, or acrylic polyols. Suitable polyols are widely commercially available. Particularly suitable polyols have a number average molecular weight ("Mn") of 500-100,000, such as 500 to 10,000, as measured by GPC. In certain embodiments, the polyol has a hydroxyl number of 20 to 400, such as 40 to 300; in other embodiments, the hydroxyl value may be 1200-2100, such as 1400-1900.

In certain embodiments, at least some of the polyols are derived from biomass. These polyols may be derived from natural oils such as castor oil, peanut oil, soybean oil or canola oil. The hydroxyl polyols present in the biomass may be naturally occurring or they may be introduced by, for example, modifying the carbon-carbon double bonds present in the oil. Natural oil derived polyols are disclosed in U.S. patent application publication No. US 2006/0041156A 1, U.S. patent No. US7,084,230, WO 2004/096882A 1, U.S. patent No. US6,686,435, U.S. patent No. US6,107,433, U.S. patent No. US6,573,354, and U.S. patent No. US6,433,121, all of which are incorporated herein by reference. Methods for modifying the carbon-carbon double bond to introduce hydroxyl groups include treatment with ozone, air oxidation, reaction with peroxide, or Hydroformylation (e.g., "Polyols and polyurethanes from Hydroformation of Soybean Oil", Journal of Polymers and dtex environmental management, Vol. 10, No. 1-2, pp. 49-52, 2002, 4 months, the entire contents of which are incorporated herein). A particularly suitable biomass-derived polyol is soy polyol. Soy polyols are commercially available from Cargill inc, urea Soy Systems co, and BioBased Technologies. In certain embodiments, the ethylenic unsaturation in the reaction product may be derived from the polyol; that is, the polyol has ethylenic unsaturation that does not react in the formation of the reaction product.

In certain embodiments, combinations of polyols may be used. In particularly suitable embodiments, the polyol comprises propylene glycol and glycerol; the propylene glycol may be 1, 3-propanediol. Any suitable ratio of 1, 3-propanediol to glycerol, such as 9: 1 to 1: 9, 4: 1 to 1: 4, 1.5: 1 to 1: 1.5, 1: 1, may be used.

The polyols used in the present invention are not the condensation reaction product of an acid functional compound and a hydroxy functional compound. Acid-functional compounds as used herein and in the context of the present invention are any compounds having one or more acid functions and optionally one or more further functions. As used herein and in the context of a hydroxy-functional compound, is meant any compound having one or more hydroxy-functional groups, and optionally one or more other functional groups. If acid-functional compounds and hydroxy-functional compounds are used to form the reaction products of the present invention, they are not reacted via polycondensation, but rather by ring-opening polymerization.

Any suitable polycarboxylic acid/anhydride may be used in accordance with the present invention. Those skilled in the art will understand that a polycarboxylic acid thereof is one having two or more acid functional groups, or residues thereof, such as anhydride groups. Suitable polycarboxylic acids/anhydrides include maleic acid/anhydride, fumaric acid/anhydride, and itaconic acid/anhydride. In certain embodiments, the polycarboxylic acid/anhydride is a biomass-derived polycarboxylic acid/anhydride. Suitable examples include itaconic acid/anhydride, which is commercially available from Cargill, Aldrich, Acros, etc. Thus, the ethylenic unsaturation in the reaction product may be derived from the polycarboxylic acid/anhydride. If the ethylenic unsaturation is derived solely from the polycarboxylic acid/anhydride, the number of carbons of the acid/anhydride is greater than four. An example of an acid/anhydride having more than four carbons is itaconic acid/anhydride.

In certain embodiments, wherein the polyol/polycarboxylic acid reaction product is also reacted with a hydroxy-carboxylic acid. Any suitable hydroxy-carboxylic acid may be used in accordance with the present invention. Those skilled in the art will appreciate that a hydroxy-carboxylic acid is one having one or more acid functional groups, and one or more hydroxyl groups, and is often referred to as a hydroxy acid. Suitable examples include 12-hydroxystearic acid, which is commercially available from Arizona Chemical Co.

It is understood that the polyol and/or polycarboxylic acid/anhydride residues or moieties present in the reaction product of the present invention have ethylenic unsaturation which renders the coating comprising the reaction product radiation curable. In certain embodiments, the polyol/polycarboxylic acid reaction product is also reacted with an additional compound having a radiation curable moiety. This reaction can be carried out in any manner standard in the art, such as by esterification or hydroxyl/NCO reaction. Suitable compounds having a radiation curable moiety include (meth) acrylates. As used herein, and as is conventional in the art, "(meth) acrylate" refers to both acrylate and the corresponding methacrylate. Suitable examples of compounds that may also react with the polyol/polycarboxylic acid reaction product include, but are not limited to, acryloyl isocyanates, including isophorone diisocyanate-hydroxyethyl acrylate adduct, and isocyanatoethyl (meth) acrylate ("AOI").

In certain embodiments, any of the polyol/polycarboxylic acid reaction products described herein may comprise 50 wt.% or more, such as 80 wt.% or more, or 90 wt.% or more, of biomass-derived material, wt.% based on total solids weight. It is understood that the biomass-derived material may be the result of a biomass-derived polyol, a biomass-derived polycarboxylic acid/anhydride, or both. If a hydroxy-carboxylic acid is used, it may also be derived from biomass.

As mentioned above, the polyols used according to the invention do not comprise condensation products of acid-functional components with hydroxyl-functional components. Thus, only the polycarboxylic acid/anhydride residues in the reaction product of components a) and b) described herein are derived from component b, the polycarboxylic acid/anhydride. However, the reaction products of a) and b) also react with other polycarboxylic acids/anhydrides. Such embodiments are therefore expressly within the scope of the present invention.

As noted above, the use of the polyol/polycarboxylic acid reaction products of the present application in coatings renders the coatings radiation curable. Radiation curable coatings are understood to be those which are cured by exposure to radiation such as actinic radiation, examples of which include ultraviolet and electron beam radiation. If the polyol/polycarboxylic acid reaction product, which is itself radiation curable, is also reacted with a compound having a radiation curable moiety, the resulting polyol/polycarboxylic acid reaction product can have an increased material curing speed and the crosslink density of the cured film is increased. The increased crosslink density may help to improve film properties such as hardness and/or abrasion resistance.

It is to be understood that if the polyol/polycarboxylic acid reaction product of the present application is used in the coating of the present invention, it may form all or part of the film-forming resin of the coating. In certain embodiments, one or more additional film-forming resins are also used in the coating. For example, the coating composition may comprise any of a variety of thermoplastic and/or thermosetting compositions known in the art. The coating composition may be a water-based or solvent-based liquid composition.

Thermosetting or curable coating compositions generally comprise a film-forming polymer or resin having functional groups that are reactive with itself or a crosslinker. The additional film-forming resin can be selected from, for example, acrylic polymers, polyester polymers, polyurethane polymers, polyamide polymers, polyether polymers, polysiloxane polymers, copolymers thereof, and mixtures thereof. In general these polymers may be of the type produced by any method known to those skilled in the art. The polymers may be solvent-borne or water dispersible, emulsifiable, or have limited water solubility. The functional groups on the film-forming resin may be selected from a variety of reactive functional groups including, for example, carboxylic acid groups, amine groups, epoxy groups, hydroxyl groups, mercapto groups, urethane groups, amide groups, urea groups, isocyanate groups (including blocked isocyanate groups), thiol groups, and combinations thereof. Suitable film-forming resin mixtures may also be used in preparing the coating compositions of the present invention.

If an additional thermosetting film former is used in the coating composition, it may be self-crosslinking, that is, it may have functional groups reactive with themselves, or a crosslinker may be added. The crosslinking agent may comprise polyisocyanates, aminoplasts, polyepoxides, beta hydroxyalkylamides, polyacids, and hydrides, organometallic acid-functional materials, polyamines, polyamides, and mixtures of any of these.

When a crosslinker is used, the coating of the invention may contain 5 to 60 wt.%, such as 10 to 50, or 20 to 40 wt.% crosslinker, based on total solids weight.

It will be understood that a coating of the present invention is "dual cured" if it also contains an additional thermoplastic or thermosetting film-forming resin. That is, the coating is cured via the radiation curable component and also via thermoplastic or thermoset curing. Alternatively, the polyol/polycarboxylic acid reaction product described herein may be further reacted with a component having functionality that renders the reaction product itself dual-cured. In certain embodiments, the reaction product may comprise radiation curable moieties as well as hydroxyl groups, which may be further reacted with a suitable crosslinking agent, for example. As used herein, the term "thermoplastic and/or thermoset component" and similar terms refer to additional thermoplastic or thermoset film-forming resins, and/or functionality on the reaction product itself, which enables the reaction product to be cured thermoplastically and/or thermoset.

If desired, the coating composition may contain, among any of the components, other optional materials well known in the art of coating formulation, such as colorants, plasticizers, antioxidants, hindered amine light stabilizers, ultraviolet light absorbers and stabilizers, surfactants, flow control agents, thixotropic agents, fillers, organic co-solvents, abrasion resistant particles, reactive diluents, catalysts, grind vehicles, and other conventional adjuvants.

"abrasion resistant particles" are those which, if used in a coating, impart some level of abrasion resistance to the coating as compared to a coating without the particles. Suitable wear resistant particles include organic and/or inorganic particles. Examples of suitable organic particles include, but are not limited to, diamond particles, such as diamond powder particles, and particles formed from carbide materials; examples of carbide particles include, but are not limited to, titanium carbide, silicon carbide, and boron carbide. Examples of suitable inorganic particles include, but are not limited to, silica; alumina; aluminum silicate; silica alumina; alkali aluminosilicates; borosilicate glass; nitrides including boron nitride and silicon nitride; oxides including titanium dioxide and zinc oxide; quartz; nepheline syenite; zircon such as in the form of zirconia; zirconia monoclinic, boulder (buddelyuite); and a foreign stone. Any size of particles may be used, as may different particles and/or mixtures of different size particles. For example, the particles can be microparticles, having an average particle size of 0.1 to 50, 0.1 to 20, 1 to 12, 1 to 10, or 3 to 6 microns, or any combination within these ranges. The particles may be nanoparticles, have an average particle size of less than 0.1 micron, such as 0.8-500, 10-100, or 100-500 nanometers, or any combination within these ranges. Silica nanoparticles are particularly suitable. The nanoparticles described above may be incorporated as a dispersion such as a dispersion in a radiation curable monomer or a dispersion in an organic solvent.

As used herein, the term "colorant" 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 flakes. 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 tints, such as those used in the paint industry and/or listed on the Dry Color Manufacturers Association (DCMA), and special effect compositions. The colorant may include, for example, a finely divided solid powder that is insoluble but wettable under the conditions of use. The colorant may be organic or inorganic and may be agglomerated or non-agglomerated. The colorant may be incorporated into the coating by milling or simple mixing. Colorants can be added by using a grind vehicle, such as an acrylic grind vehicle, the use of which is well known to those skilled in the art.

Examples of pigments and/or pigment compositions include, but are not limited to, carbazole dioxazine crude pigment, azo, monoazo, diazo, naphthol AS, salts (lakes), benzimidazolone, condensation, metal complexes, isoindolinone, isoindoline, and polycyclic phthalocyanine, quinacridone, perylene, peryleneketone, diketopyrrolopyrrole, thioindigo, anthraquinone, indanthrone, anthrapyrimidine (anthrypirimidine), flavanthrone, pyranthrone, anthanthrone, dioxazine, triarylcarbonium, quinophthalone (quinophthalone) pigments, diketopyrrolopyrrole red ("DPPBO red"), titanium dioxide, carbon black, carbon fiber, graphite, other conductive pigments and/or fillers, and mixtures thereof. The terms "pigment" and "coloring filler" may be used interchangeably.

Examples of dyes include, but are not limited to, those that are solvent and/or aqueous based such as acid dyes, azo dyes, basic dyes, direct dyes, disperse dyes, reactive dyes, solvent dyes, sulfur dyes, mordant dyes, such as bismuth vanadate, anthraquinone, perylene aluminum, quinacridone, thiazole, thiazine, azo, indigoid, nitro, nitroso, oxazine, phthalocyanine, quinoline, 1, 2-stilbene, and triphenylmethane,

examples of coloring agents include, but are not limited to, pigments dispersed in an aqueous-based or water-compatible carrier such as AQUA-CHEM 896 commercially available from Degussa, inc, and CHARISMA COLORANTS and maxiner inclusion COLORANTS commercially available from AccurateDispersions division, Eastman Chemicals, inc.

As noted above, the colorant may be in the form of a dispersion, including but not limited to a nanoparticle dispersion. Nanoparticle dispersions can include one or more highly dispersed nanoparticle colorants and/or colorant particles that produce a desired visible color and/or opacity and/or visual effect. Nanoparticle dispersions can include colorants such as pigments or dyes having particle sizes less than 150 nanometers, such as less than 70 nanometers, or less than 30 nanometers. The nanoparticles may be prepared by comminuting organic or inorganic pigments with an abrasive having a particle size of less than 0.5 mm. Examples of nanoparticle dispersions and methods for their preparation are disclosed in U.S. Pat. No. 6,875,800B 2, the disclosure of which is incorporated herein by reference. Nanoparticle dispersions can also be prepared by crystallization, precipitation, gas phase condensation, and chemical abrasion (i.e., partial dissolution). To minimize re-agglomeration 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 having dispersed therein discrete "composite particles" comprising nanoparticles and a resin coating on the nanoparticles. Examples of resin-coated nanoparticle dispersions and methods for their preparation are disclosed in U.S. patent application publication No. 10/876,031 filed 24.6.2004, the disclosures of which are incorporated herein by reference in their entirety, U.S. patent application publication No. 2005-0287348 a1 filed 24.6.2004, and U.S. patent application publication No. 2006-0251897 filed 20.1.2006, which are also incorporated herein by reference in their entirety.

Examples of special effect components that may be used include pigments and/or compositions that produce one or more appearance effects such as reflectance, pearl powder, metallic sheen, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, goniochromism (goniochromism) and/or color-change. Additional special effect components may provide other visible properties such as opacity or texture. In a non-limiting embodiment, the special effect component can produce a color shift, such that the color of the coating changes when the coating is viewed at different angles. Examples of color effect components are disclosed in U.S. Pat. No. 6,894,086, incorporated herein by reference in its entirety. Additional color effect components may include transparent coated mica and/or synthetic mica, coated silica, coated alumina, transparent liquid crystal pigments, liquid crystal coatings, and/or any composition wherein interference results from a refractive index difference within the material rather than from a refractive index difference between the surface of the material and air.

In certain non-limiting embodiments, photosensitive compositions and/or photochromic compositions that reversibly change 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 particular 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 removed, the photochromic and/or photosensitive composition can return to a quiescent state in which the composition reverts to the original color. In one non-limiting embodiment, the photochromic and/or photosensitive composition can be colorless in the non-excited state and exhibit an excited state color. Full color-change can be manifested within milliseconds to minutes, such as 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 attached and/or at least partially bound to the polymer and/or polymeric material of the polymerizable component by, for example, covalent bonds. In contrast to some coatings in which the photosensitive composition can migrate out of the coating and crystallize into the substrate, the amount of photosensitive composition and/or photochromic composition attached to and/or at least partially bound to the polymer and/or polymerizable component migrates out of the coating is minimized, in accordance with a non-limiting embodiment of the present invention. Examples of photosensitive compositions and/or photochromic compositions and methods for their preparation are disclosed in U.S. patent application No. 10/892,919 filed on 7, 16, 2004 and incorporated herein by reference in its entirety.

Generally, the colorant is present in an amount sufficient to impart the desired visual 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, with weight percent being based on the total weight of the composition.

Since the coating compositions of the present invention are liquids, they may also comprise solvents and/or reactive diluents; alternatively, they may be 100% solid. Suitable solvents include water, organic solvent(s) and/or mixtures thereof. Suitable organic solvents include glycols, glycol ether alcohols, ketones and aromatic hydrocarbons, such as xylene, as well as toluene, acetates, mineral spirits, naphtha and/or mixtures thereof. "acetate" includes glycol ether acetates. The solvent may be derived from biomass. Examples of biomass-derived solvents include lactates and soyate. In certain embodiments, the solvent is a non-aqueous solvent. "non-aqueous solvent" and like terms mean less than 50% water in the solvent. For example, the solvent may have less than 10%, or even less than 5% water. It is clear that solvent mixtures that include or do not include water in an amount less than 50% can form "non-aqueous solvents". In other embodiments, the coating is aqueous or water-based. This means that the solvent is 50% or more water. In these embodiments the solvent is less than 50%, such as less than 20%, less than 10%, less than 5%, or less than 2%. In some embodiments, some or all of the solvents may be reactive diluents that co-cure with other components in the formulation. The reactive diluent may be derived from biomass.

The compositions of the present invention may further comprise photoinitiators, such as those used in the art to catalyze or accelerate curing, provided that such curing is by exposure to ultraviolet light. Any suitable photoinitiator may be used, including any known photoinitiator, such as benzophenone, benzoin, acetophenone, benzoin methyl ether, Michler's ketone, benzoin butyl ether, xanthone, thioxanthone, phenyl ethyl ketone, fluorenone, carbazole, diethoxyacetophenone, the 2-, 3-and 4-methylacetophenones and methoxyacetophenones, the 2-and 3-chlorothianthrone and chlorothioxanthone, 2-acetyl-4-methylphenyl acetate, 2' -dimethoxy-2-phenylacetophenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, 3-and 4-allyl-acetophenone, p-diacetylbenzene, 3-chloro-2-nonyloxanthone, 2-chlorobenzophenone, benzophenone, and mixtures thereof, 4-methoxybenzophenone, 2 ', 4, 4' -tetrachlorobenzophenone, 2-chloro-4 '-methylbenzophenone, 4-chloro-4' -methylbenzophenone, 3-methylbenzophenone, 4-tert-butylbenzophenone, isobutyl ether-benzoin acetate, benzil benzilic acid, aminobenzoate, methyl blue, 2-diethoxyacetophenone, 9, 10-phenanthrenequinone, 2-methylanthraquinone, 2-ethylanthraquinone, 1-tert-butylanthraquinone, 1, 4-naphthoquinone, isopropylthioxanthone, 2-methylthiothioxanthone, 2-decylthioxanthone, 2-laurylthiothioxanthone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinoacetone-1-morpholino ketone, And combinations thereof.

The coatings of the present application can be applied to any substrate known in the art, such as substrates for automobiles and industrial substrates. These substrates may be, for example, metallic or non-metallic, including polymeric, plastics, polycarbonate/polyacrylonitrile butadiene styrene ("PC/ABS"), polyamide, wood, veneer, wood composites, particle board, medium density fiberboard, cement, stone, and the like. In a particularly suitable embodiment of the invention, the substrate itself is biodegradable. Biodegradable substrates include, for example, paper, wood, and biodegradable plastics such as cellulose, poly (lactic acid), poly (3-hydroxybutyrate), and starch-based plastics. Alternatively, the substrate may be one that is recycled. The substrate may also be one that has been treated in some manner to impart color or other visual effect. For example, a painted wood substrate may then be coated according to the present invention, such as a substrate that has been coated with one or more other coatings.

As used herein, the term "polyamide" in relation to a substrate refers to a substrate made from a polymer comprising repeating units of the formula:

wherein R is hydrogen or alkyl. The polyamide may be any of a large class of polyamides based on aliphatic, cycloaliphatic, or aromatic groups in the chain. Formally they can be represented by the product diamine polycondensation product with a diacid and/or diacid chloride, by an amino acid self-polycondensation product such as omega-aminoundecanoic acid, or by a cyclic lactam ring-opening reaction product such as caprolactam, lauryllactam, or pyrrolidone. They may comprise one or more alkylene, arylene, or arylene repeat units. The polyamide may be crystalline or amorphous. In certain embodiments, the polyamide substrate comprises a crystalline polyamide having alkylene repeat units of 4 to 12 carbon atoms, such as poly (caprolactam) (nylon 6), poly (dodecyllactam) (nylon 12), poly (omega-aminoundecanoic acid) (nylon 11), poly (hexamethylene adipamide) (nylon 6.6), poly (hexamethylene sebacamide) (nylon 6.10), and/or alkylene/arylene copolyamides such as those made from m-xylylenediamine and adipic acid (nylon MXD 6). The term "nylon" includes all of these products and any other compounds mentioned in the art as nylons. Amorphous polyamides, such as those derived from isophorone diamine or trimethyl cyclohexane diamine, may also be used. Polyamide blends may also be used.

As used herein, the term "polyamide", when used in reference to a substrate, includes reinforced polyamide substrates; a reinforced polyamide substrate is a polyamide substrate made from a polyamide that has been reinforced by including, for example, a fibrous material such as glass fibers or carbon fibers, or an inorganic filler such as calcium carbonate to produce a polyamide having increased rigidity, strength, and/or heat resistance relative to a similar polyamide that does not include the reinforcing material. Reinforced polyamides suitable as substrates according to certain embodiments of the present invention are commercially available and include, by way of example, those materials commercially available from Solvay Advanced Polymers under the name IXEF and include, for example, the IXEF 1000, 1500, 1600, 2000, 2500, 3000 and 5000 series products; those materials commercially available from EMS-Chemie inc, Sumter, south carolina under the tradenames GRILAMID, GRIVORY, GRILON and GRILFLEX; and DuPont Engineered Polymers such as those sold under the trade names THERMX and MINLON.

The coatings of the present invention are applied in any manner standardized in the art, such as electrocoating, spraying, electrostatic spraying, dipping, rolling, brushing, and the like.

The coating may be applied to any dry film thickness, such as 0.1-2.0 mils, 0.2-0.8 mils, or 0.3-0.6 mils. The coatings of the present invention may be used alone or in combination with other stains and/or coatings as described above. For example, the coating may or may not contain colorants and may be used as a primer, basecoat, topcoat, automotive refinish coating, and the like. For substrates coated with multiple layers of coatings, one or more of those coatings may be a coating as described herein. In certain embodiments, the coating of the present invention may be a clear coat over one or more other coatings.

The radiation curable coatings of the present invention can be cured upon exposure to high energy or actinic radiation. High energy particle radiation classes include those high energy electrons such as those originating from isotopes such as strontium-90, or from a strong electron beam generated by a particle accelerator. Electron beam curing is most useful for this application if very fast and economical speeds are desired. In some systems, a cure cycle of less than about 1 second, with a total radiation dose of less than about 0.25 mrads, may be used.

One type of actinic radiation according to the present invention is ultraviolet light; other forms of actinic radiation, such as RS Sunlamps types, carbon arc lamps, xenon arc lamps, mercury lamps, tungsten halogen lamps, and the like, commonly found in radiation emitted by the sun or generated from artificial sources, are also suitable. If the coating contains a photo-curing rate accelerator, the ultraviolet radiation can be used most efficiently. Typical cure periods are 1 second to 15 minutes.

As used herein, unless otherwise specifically stated, all numerical readings such as those expressing values, ranges, amounts or percentages are as if prefaced by the word "about", even if the term "about" does not expressly appear. Moreover, any numerical range recited herein is intended to include all sub-ranges subsumed therein. Singular encompasses plural and vice versa. For example, although the application including the claims states that "a" polyol, "a" polycarboxylic acid/anhydride, "a" polyol/polycarboxylic acid reaction product, "a" hydroxy-carboxylic acid, "a" crosslinker, "a" compound has "a" radiation curable moiety, one or more of each of these as well as any other components may be used. "including" means "including, but not limited to". As used herein, the term "polymer" refers to oligomers and both homopolymers and copolymers, and the prefix "poly" refers to two or more.

Examples

The following examples are intended to illustrate the invention and are not to be construed as limiting the invention in any way.

Example 1

Polyester-1-4 was prepared as follows:

TABLE 1

¹Commercially available from DuPont-Tate&Lyle，Inc.

²Commercially available from Cargill, Inc.

³Cenwax-A, trade Mark, commercially available from Arizona Chemicals.

⁴Commercially available from Cargill, Inc.

Charge #1 was charged to a 5-liter, 4-necked flask equipped with an electric steel stirring blade, nitrogen inlet, thermocouple, heating through a mantle controlled by the thermocouple via a temperature feedback control device, and a facility for azeotropic distillation using a dean-Stark trap with a water condenser on top. A column packed with a ceramic helix was installed between the flask and the dean-stark trap to provide additional control over the azeotropic distillation rate.

Stirring and a nitrogen flow of 0.2scft/min were started and feed #2 was added to make a suspension. Heating was then started to set the temperature to 140 ℃. When the internal temperature reached 133-135 ℃, water and xylene began to collect in the dean-Stark trap. The water collected at the bottom of the trap was withdrawn at approximately 10 minute intervals and the set temperature interval was increased by 5 degrees until a temperature of 180 ℃ was reached when a steady reflux was required and approximately 1 gram of water was collected per minute. At this point, no more water was collected in the trap and the acid number decreased. The reaction was allowed to cool to 100 ℃ and then the xylene was evaporated under vacuum of 5-9 inches of mercury.

Example 2

Urethane-acrylate-1-3 was prepared as follows:

TABLE 2

⁵Acryloxyethyl isocyanate-Versatile monomer, commercially available from Showa Denko, japan.

ND is not detected

Charge #1, which consisted of the corresponding polyester of example 1, was charged to a 2-liter, 4-neck flask equipped with an electric steel stirring blade, a water condenser, a thermocouple, a sparge tube to deliver a stream of nitrogen-air mixture beneath the surface of the reaction mixture, and an oxygen probe to measure the gas phase oxygen content in the headspace. Stirring and a nitrogen-air flow of 0.2scft/min were started and the oxygen concentration in the headspace was adjusted to 5% v/v by the nitrogen-air flow.

When the oxygen concentration stabilized at 5%, feed #2 was added dropwise at a rate that maintained the temperature below 80 ℃, such as at 50 to 70 ℃.

When feed #2 was completed, the final reaction temperature of 70 ℃ began to drop, indicating that the AOI had reacted rapidly at the time it was added. After 15 minutes, the NCO content was monitored by IR. At 2267cm^-1No bands were present.

The product was injected into unlined metal cans.

Examples 3, 4, 5

The radiation curable coating compositions of examples 3, 4, and 5 were prepared from the ingredients listed in table 3. Charge V was then added to the flask followed by either charge I or charge II with stirring. Charge III and IV were then added sequentially with stirring. The mixture was stirred for a suitable time to form a clear solution. The resulting conjugate was filtered twice through a 0.45 μm filter.

TABLE 3

⁶Photoinitiators, commercially available from CIBA Specialty Chemicals.

⁷Photoinitiators, commercially available from CIBA Specialty Chemicals.

⁸Photoinitiators, commercially available from Rahn, Inc.

⁹Hindered amine light stabilizers, commercialAvailable from CIBA Specialty Chemicals.

¹⁰Flow modifiers, commercially available from Cytec Surface Specialties.

¹¹Flow modifiers, commercially available from Tego Chemie, Essen, germany.

¹²Silica organosol, commercially available from Hanse Chemie AG, geethacht, is an 50/50 weight percent dispersion of amorphous silica particles having an average primary particle size of about 20 nanometers in trimethylolpropane triacrylate.

To coat the samples with the previous composition, MAKROLON clear polycarbonate plaques (Bayer AG) were wiped with 2-propanol. The coating solution was spin coated onto unprimed plaques and exposed to air with an H bulb using a UVA dose of 1J/cm²And 0.6W/cm²The strength of (c) is high. Samples were prepared with final dry film thickness ranging from 10-20 μm. The coated samples were evaluated for adhesion, optical clarity, and Taber abrasion resistance.

As indicated in table 4, the polycarbonate samples coated with the coatings of the present invention were highly transparent with low initial haze and varying levels of bio-content. In particular, with respect to example 5, better abrasion resistance was obtained with a biocontent higher than 20%. These bio-based coatings also provide excellent adhesion and abrasion resistance.

TABLE 4

¹³The biological content is as follows: weight percent biomass material relative to total coating weight in the dry film.

¹⁴Adhesion: crosscoat, Nichiban LP-24 tape. Rating scale 0-5 (no adhesion-100% adhesion after tape stretching))。

¹⁵Haze% was measured with a Hunter Lab spectrophotometer.

¹⁶Taber abrasion: taber 5150 abrasion tester, CS-10 wheels, S-11 smooth-surface disk, 500 g weight. The% haze was measured after 300 Taber abrasion cycles. Haze% < 25% after 300 Taber abrasion cycles was acceptable.

Examples 6, 7 and 8

The standard bio-based coating compositions of examples 6, 7, and 8 were prepared from the ingredients listed in table 5. Charge I was added to the appropriate flask with stirring and stirred. Feed II was then added to the flask with stirring to relay feed III and IV. The mixture was stirred for a suitable time to form a clear solution.

TABLE 5

¹⁷Dipentaerythritol pentaacrylate, commercially available from Sartomer Company, inc.

¹⁸Ethoxylated trimethylolpropane triacrylate, commercially available from Sartomer Company, inc., Exton, PA.

¹⁹Flow modifier, commercially available from Dow Corning.

To coat the samples with the previous composition, MAKROLON clear polycarbonate plaques (Bayer AG) were wiped with 2-propanol. The coating solution was spin coated onto unprimed plaques and exposed to air with an H bulb using a UVA dose of 1J/cm²And 0.6W/cm²The strength of (c) is high. The final dry film thickness of the prepared samples ranged from 15 to 18 μm. The coated samples were tested for adhesion, optical clarity, and Taber abrasion resistance.

As indicated in table 6, the polycarbonate samples were coated with these bio-based UV transparent coatings. In the present invention, these coatings with varying levels of bio-content are highly transparent with low initial haze and good adhesion and abrasion resistance.

TABLE 6

Although specific embodiments of the invention have been described above for purposes of illustration, it will be evident to 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 (14)

1. A radiation curable liquid coating comprising:

a) a polyol;

b) polycarboxylic acids/anhydrides; and

c) a reaction product of a compound comprising a radiation curable moiety comprising an acryloyl isocyanate,

wherein at least some of a) and/or b) are derived from biomass, wherein the polyol is not a condensation reaction product of an acid functional compound and a hydroxyl functional compound, wherein the reaction product comprises ethylenic unsaturation derived from a), and/or b), but if derived solely from b, then b has more than four carbons.

2. The coating of claim 1, wherein the polyol comprises 1, 3-propanediol.

3. The coating of claim 2, wherein the polyol further comprises glycerol.

4. The coating of claim 3, wherein the polycarboxylic acid/anhydride comprises itaconic acid/anhydride.

5. The coating of claim 1, wherein the reaction product is further reacted with a hydroxycarboxylic acid.

6. The coating of claim 5, wherein the hydroxycarboxylic acid comprises 12-hydroxystearic acid.

7. The coating of claim 1, wherein the acryloyl isocyanate comprises acryloyloxyethyl isocyanate.

8. The coating of claim 1, further comprising abrasion resistant particles.

9. The coating of claim 8, wherein the abrasion resistant particles comprise silica nanoparticles.

10. The coating of claim 1, wherein the coating is a dual cure coating.

11. The coating of claim 1, wherein the coating is a clear coating.

12. The coating of claim 1, wherein the coating comprises 50 wt% or more of the biomass-derived products.

13. The coating of claim 1, wherein the polyol is reacted with a compound comprising a radiation curable moiety prior to reaction with the polycarboxylic acid/anhydride.

14. A substrate at least partially coated with the coating of claim 1.