SULFOPOLYESTER-CONTAINING PHOTOPOLYMER SYSTEMS

Abstract: A low molecular weight, film-forming, polymerizable, ethylenically-unsaturated compound is water- and organic solvent-soluble (i.e., soluble in both water and organic sol­ vents) but is readily converted on exposure to actinic radiation to a polymer that is solvent-insoluble (i.e., not soluble in water, organic solvents, or mixtures of water and organic solvents) and, in certain examples, is hydrophobic. The compound comprises the ethylenically-unsaturated derivative (i.e., an ester or an amide) of a sulfopolyol or sulfopolyamine having an ethylenic unsaturated functionality of 2 to 18 and an equiva­ lent weight per ethylenic unsaturated functionality of less than 2500.

Description: This invention relates to a water- and organic solvent-soluble compound which is an ethylenically-unsaturated derivative of a sulfopolyol or suflopolyamine which on exposure to energy is converted to a water- and organic solvent-insoluble polymer. In another aspect, the invention relates to the deposition on a substrate of a layer of water-and solvent-soluble sulfocompound and to the imagewise exposure of the coating to radiation to polymerise selects areas of the coating the unexposed portions of the coating being removed with solvent. Water-soluble polyesters which are curable to insoluble resins on exposure to heat or radiation are known. U.S. Patent No. 2,845,402 discloses polyesters that on heating in the presence of a catalyst cure to insoluble resins and that are the reaction products of polyalkyleneoxide polyols and dicarboxylic acids. U.S. Patent No. 4,073,777 discloses polyesters and polyesteramides that crosslink to water-insoluble resins on exposure to radiation and that are the reaction products of (1) at least one dicarboxylic acid, (2) at least one glycol, (3) sufficient sulfoaromatic dicarboxylic acid, dihydroxy, or diamino compound to provide water dispersibility to the reaction product, and (4) an unsaturated mono or dicarboxylic acid. In such a reaction product, the polymerizable unsaturated group is present in the polymer backbone and not in a terminal group. Furthermore, the sulfo group is distributed statistically in the polymer. The water-soluble polyesters described in the above cited patents, although convertible on exposure to actinic radiation to water-insoluble resins, are high molecular weight compounds that are prepared by high temperature reactions requiring the heating of unsaturated reactants to temperatures of about 270°C for long periods of time. Such high molecular weight compounds have a high melt viscosity that adds to the difficulties encountered in handling the compounds. Also, because of the harsh and prolonged heating required in their preparation, the ethylenic unsaturation does not always survive. The present invention provides an ethylenically-unsaturated sulfocompound which is the poly(ethylenically-unsaturated ester or amide) of a sulfopolyol or sulfopolyamine comprising the reaction product provided by the following stops in sequence of: a. providing a sulfopolyol or sulfopolyamine which is the reaction product of 1) one mole of a sulfodicarboxylic acid and 2) about two moles of an aliphatic polyol having (c+1) hydroxyl groups attached to a saturated linear chain of up to about 55 carbon atoms in units of 2 to 12 -CH₂ groups separated by 0 to 8 groups or about 2 moles of a polyamine having (c + 1) amine groups attached to a saturated linear chain of up to about 55 carbon atoms in units of 2 to 12 -CH₂- groups separated by 0 to 22 -O- atoms and 0 to 8 groups, the polyol or polyamine having a molecular weight of less than 1000 and c being an integer of 1, 2, or 3 ; and b. reacting the resulting sulfopolyol or polyamine with 2 c moles of either 1), 2), or 3), in which 1) is a compound selected from (a) 2 alkenylazlactones having the formula wherein R is hydrogen or methyl; R¹ is a covalent bond, -CH₂- or -CH₂CH₂-, R² and R³ are independently hydrogen or methyl; and (b) ethylenically-unsaturated isocyanates having the formula wherein R⁴ is a covalent bond, -CH₂-, wherein R⁵ is a linear or branched chain of 1 to 12 carbon atoms optionally containing one catenary oxygen atom or group or R⁵ is a 5- or 6-membered carbocyclic group optionally substituted by lower alkyl groups having 1 to 4 carbon atoms, the carbocyclic group having a total of up to 12 carbon atoms, and R⁶ is an organic group selected from linear or branched alkylene groups having 2 to 12 carbon atoms, a cyclopentamethylene group, a cyclohexamethylene group, a 5- or 6-membered azacyclic group, a phenylene group, a naphthalene group, a phenylenemethylene-phenylene group, the organic group optionally substituted by up to four lower alkyl groups having 1 to 4 carbon atoms and a total of up to 15 carbon atoms: or 2) a diisocyanate having the formula the reaction product of said sulfopolyester polyol or polyamine and said diisocyanate then being reacted with 2 c moles of an ethylenically-unsaturated alcohol having the formula wherein R and R⁶ are as defined above; R⁷ is R⁸ is a polyvalent aliphatic group selected from linear and branched alkyl groups having a valence of (a + 1), 2 to 12 carbon atoms, no or one nonperoxidic catenary oxygen atom, and no or one group, and alicyclic groups having a 5- or 6-atom carbocyclic structure optionally substituted by up to 4 lower alkyl groups having 1 to 4 carbon atoms and a total of up to 12 carbon atoms, and a is an integer of 1, 2, or 3; or 3) the reaction product of one mole of organic diisocyanate of Formula III and one mole of an ethylenically-unsaturated alcohol of Formula IV; there being essentially no hydroxyl, amino, or isocyanate groups remaining after the reaction of a. with b.1), b.2), or b.3), wherein the ethylenically-unsaturated sulfocompound contains a single central sulfo group. The ethylenically-unsaturated sulfocompound of the invention is film-forming, polymerizable, hydrophilic and solvent-soluble (i.e., soluble in both water and organic solvents) but is readily converted on exposure to actinic radiation to a polymer that is solvent-insoluble (i.e., not soluble in water, organic solvents, or mixtures of water and organic solvents) and, in certain examples, is hydrophobic. The invention also provides an intermediate isocyanate-terminated sulfocompound comprising the reaction product provided by the following steps in sequence: a. providing a sulfopolyol or sulfopolyamine which is the reaction product of 1) one mole of a sulfodicarboxylic acid and 2) about two moles of an aliphatic polyol having (c+1) hydroxyl groups attached to a saturated linear chain of up to about 55 carbon atoms in units of 2 to 12 -CH₂ groups separated by 0 to 8 groups or about 2 moles a polyamine having (c + 1) amine groups attached to a saturated linear chain of up to about 55 carbon atoms in units of 2 to 12 -CH₂- groups separated by 0 to 22 -O- atoms and 0 to 8 groups, the polyol and polyamine having a molecular weight of less than 1000 and c being an integer of 1, 2, or 3 ; and b. reacting the resulting sulfopolyol or polyamine with 2 c moles of a diisocyanate having the formula wherein R⁶ is an organic group selected from linear or branched alkylene groups having 2 to 12 carbon atoms, a cyclopentamethylene group, a cyclohexamethylene group, a 5- or 6-membered azacyclic group, a phenylene group, a naphthalene group, a phenylenemethylene-phenylene group, the organic group optionally substituted by up to four lower alkyl groups having 1 to 4 carbon atoms and a total of up to 15 carbon atoms, to provide said isocyanate-terminated sulfocompound which has a single central sulfo group. Preferably, the low molecular weight, film-forming, polymerizable, ethylenically-unsaturated sulfocompound has an equivalent weight per ethylenic unsaturated functionality of about 300 to 1000. As the unsaturated functionality is increased above about 600, the polymer becomes increasingly hydrophilic and as the functionality is decreased below about 600, the polymer becomes increasingly hydrophobic. As used in this application: "poly(ethylenically-unsaturated ester or amide)" means an organic compound having an ethylenically-unsaturated group (i.e., H₂C=CH- or H₂C=C(CH₃)-) that is connected to the compound by means of at least one of a bond, a methylene group, a carboxylate "low molecular weight ester" means a compound that is the ethylenically-unsaturated derivative of a sulfoester that is the reaction product of one mole of a sulfodicarboxylic acid and no more than two moles of polyol or polyamine having 2 to 4 hydroxyl or amino groups followed by reaction with 2 to 6 moles of an ethylenically-unsaturated compound. The compound therefore, has only one sulfo group and generally has a molecular weight of less than 6500, and preferably less than 4000; "lower alkyl" means 1 to 4 carbon atoms; "catenary" means in the main chain or backbone and not in a pendent or terminal group; "sulfo" means a -SO₃H group or a salt thereof; and "sulfocompound" means a water- and organic solvent-soluble compound which is an ethylenically-unsaturated derivative (i.e., an ester or an amide) of a sulfopolyol or sulfopolyamine. The water- and organic solvent-soluble, low molecular weight, film-forming, polymerizable, ethylenically-unsaturated sulfocompounds of the invention preferably have the general formulas wherein: R, R⁶, R⁷, R⁸ and c are as defined in the "Summary of the Invention" section; R⁹ is an arenetriyl group (trivalent arene group) having 6 to 12 carbon atoms or an alkanetriyl (trivalent alkane group) group having 2 to 12 carbon atoms remaining after the removal of carboxyl and sulfo groups from sulfoarene- and sulfoalkane dicarboxylic acids having the formula in which M is a cation, (preferably M is Na, but M can for example be H, K, Li, an alkaline earth metal cation (e.g., Mg, Ca, or Ba), or a primary, secondary, tertiary, or quaternary ammonium cation such as ammonium, methyl-ammonium, butylammonium, diethylammonium, triethylammonium, tetraethylammonium, or benzyltrimethylammonium cation); R¹⁰ is a linear aliphatic group having a valence of (c+1) consisting of a saturated chain of up to about 55 carbon atoms in units of 2 to 12 -CH₂- groups separated by 0 to 22 -O-atoms and 0 to 8 groups, the aliphatic group having a molecular weight of less than 1000, wherein c is an integer of 1, 2, or 3; R¹¹ is in which R¹, R², R³, and R⁴ are as defined above; X is -O- or -NH-; and a is an integer of 1, 2, or 3. The coating compositions of the invention are energy-curable and preferably comprise the low molecular weight, solvent-soluble, film-forming, polymerizable urethane group-containing compounds of Formulas VI and VII and a free radical generating compound that generates free radicals on application of energy. The low molecular weight, water- and organic solvent-soluble, film-forming, polymerizable sulfocompound of the invention can be prepared by procedures well known in the art, preferably by the reaction of one mole of sulfoarene or sulfoalkane dicarboxylic acid, Formula VIII, (or their esters prepared from an alcohol of low molecular weight, i.e. below about 94, their acid anhydrides, or their acid halides) with about two moles (e.g. 1.95 to 2.05 moles) of aliphatic monomeric or polymeric polyol having (c + 1) hydroxyl groups or with about two moles (e.g. 1.95 to 2.05 moles) of polyamine having (c + 1) amino groups, thereby forming a sulfopolyol or sulfopolyamine having 2 c hydroxyl or amino groups, wherein c is an integer of 1, 2, or 3. The sulfopolyol or sulfopolyamine is then caused to react with either: (i) 2 c moles of ethenyl azlactone of Formula I, or (ii) with 2 c moles of ethylenically-unsaturated isocyanate of Formula II, preferably an isocyanatoalkyl acrylate or polyacrylate, or (iii) with 2 c moles of an organic diisocyanate of Formula III followed by reaction with 2 c moles of an ethylenically-unsaturated alcohol of Formula IV, preferably a hydroxyalkyl acrylate, or (iv) with 2 c moles of the reaction product of one mole of organic diisocyanate of Formula III with one mole of an ethylenically-unsaturated alcohol of Formula IV, preferably a ` hydroxyalkyl acrylate. As is known in the art, these reactions can be performed in the presence of a mercury, lead or tin catalyst such as dibutyltin dilaurate. Preferably, the catalyst is a tertiary amine, tricalcium aluminate, or the potassium salt of a molybdenum ester of triethyleneglycol as is disclosed in U.S. Patent No. 2,916,464. The preparation of the sulfopolyol or sulfopolyamine can be carried out by heating the reactants for about 2 to 20 hours, preferably 4 to 10 hours, at temperatures from 150 to 300°C, preferably 200 to 250°C, under reduced pressure or an inert atmosphere. Reactions in which one of the components is an acrylic group-containing compound need be heated at a temperature of only about 20 to 100°C, preferably 30 to 60°C for 1 to 10 hours. Aliphatic polyols, (HO)c R ¹⁰-OH, useful in preparing the water- and organic solvent-soluble sulfocompounds of the invention have a molecular weight of 62 to 1000 and include, for example, monomeric and polymeric polyols having two to four hydroxyl groups. Examples of the monomeric polyols include ethylene glycol, propylene glycol, butylene glycol, hexamethylene glycol, 1,1,1-trimethylolpropane, pentaerythritol, and the like. Examples of polymeric polyols include the polyoxyalkylene polyols, i.e., the diols, triols, and tetrols, the polyester diols, triols, and tetrols of organic dicarboxylic acids and polyhydric alcohols, and the polylactone diols, triols, and tetrols having a molecular weight of 106 to about 1000. Examples of polymeric polyols include polyoxyethylene diols, triols and tetrols such as the Carbowax TM polyols available from Union Carbide, the polyoxytetramethylenediols such as Polymeg TM polyols available from Quaker Oats Company, the polyester polyols such as the Multron TM poly(ethyleneadipate)polyols available from Mobay Chemical Company, and the polycaprolactone polyols such as the PCP TM polyols available from Union Carbide. Aliphatic polyamines (H₂N)c R ¹⁰-OH, useful in preparing the sulfocompounds of the invention are the polyamines available from Jefferson Chemical Co., Inc., a subsidiary of Texaco, Inc., under the tradename Jeffamine TM such as Jeffamine TM D-400, a polyoxypropylene diamine having a molecular weight of about 400; Jeffamine TM D-230, a polyoxypropylene diamine having a molecular weight of about 230: Jeffamine TM T-403, a polyoxypropylene triamine having a molecular weight of about 400; and Jeffamine TM ED 600 and ED 900, which are polyoxyethylene diamines having molecular weights of 600 and 900, respectively. Sulfoarene- and sulfoalkanedicarboxylic acids of Formula VIII useful for preparation of the water- and solvent-soluble sulfocompounds of the invention are any of the known sulfoarene- and sulfoalkanedicarboxylic acids. Examples of these include sulfoalkanedicarboxylic acids such as sulfosuccinic acid, 2-sulfoglutaric acid, 3-sulfoglutaric acid and 2-sulfododecanedioic acid; sulfoarenedicarboxylic acids such as 5-sulfoisophthalic acid, 2-sulfoterephthalic acid, 5-sulfonaphthalene-1,4-dicarboxylic acid; sulfobenzylmalonic acids such as those described in U.S. Patent No. 3,821,281; and sulfofluorene-dicarboxylic acids such as 9,9-di(2'-carboxyethyl)fluorene-2-sulfonic acid described in British Patent No. 1,006,579. It is to be understood that the corresponding lower alkyl esters, halides, anhydrides, and salts of the above sulfonic acids can also be used in the preparation. Acrylic and methacrylic acids, their esters and acid halides that can be used to prepare the ethylenically-unsaturated carboxylate esters of the invention are well known and include acrylic and methacrylic acid, the esters of low molecular weight alcohols, such as methyl, ethyl, propyl and butyl acrylate and methacrylate, and the acid halides such as acrylchloride and methacrylchloride. 2-Alkenylazlactones, compounds of Formula I, which can be caused to react with sulfopolyols and sulfopolyamines to form the ethenically-unsaturated compounds of the invention are ethylenically-unsaturated compounds having a reactivity similar to the isocyanates for reaction with a nucleophilic group. Examples of 2-alkenylazlactones include 2-ethenyl-1,3-oxazolin-5-one, 2-isopropenyl-1,3-oxazolin-5-one, 2-ethenyl-4,4-dimethyl-1,3-oxazolin-5-one, 2-isopropenyl-4,4-dimethyl-1,3-oxazolin-5-one, 2-ethenyl-5,6-dihydro-5,5-dimethyl-4 H -1,3-oxazin-6-one, and 2-isopropenyl-5,6-dihydro-5,5-dimethyl-4 H -1,3-oxazin-6-one. The reaction with the sulfopolyol is performed at 0°C to 50°C under atmospheric pressure in the presence of about 0.1 to 5 percent by weight of a Lewis acid such as BF₃-etherate, AlCl₃, or SnCl₄, as catalyst. The reaction with the sulfopolyamine is relatively rapid and is accompanied by a mild exotherm and generally does not require a catalyst. Other 2-alkenylazlactones and conditions that can be used are described in EP-A-0091956. Ethylenically-unsaturated isocyanates of Formula II useful in preparing the ethylenically-unsaturated sulfocompounds of the invention include 2-isocyanatoethyl acrylate and methacrylate, 3-isocyanatopropyl acrylate and methacrylate, 2-acrylamidoethylisocyanate, 3-acrylamidopropylisocyanate, 3-methacrylamidopropylisocyanate, 2,3-bis(acryloyloxy)propylisocyanate 3,3,3-tris(acryloyloxymethyl)propylisocyanate, 4-methacryloyloxycyclohexylisocyanate, 5-acryloyloxymethyl-3,-3,5-trimethylcyclohexylisocyanate, allylisocyanate, methallylisocyanate, and the reaction product of the hydroxyalkyl acrylates and diisocyanates given below. Ethylenically-unsaturated alcohols of Formula IV useful in preparing the ethylenically-unsaturated sulfocompounds of the invention are allyl and methallyl alcohols, 2-hydroxyethyl acrylate and methacrylate, 3-hydroxypropyl acrylate and methacrylate, 1,1,1-trimethylolpropane diacrylate, and dimethacrylate pentaerythritol triacrylate and trimethacrylate. Hydroxyalkyl acrylates or methacrylates that can be reacted with an organic diisocyanate to form isocyanatoacrylates and methacrylates are well known and described in many patents, such, as for example U.S. Patent No. 4,108,840, col. 8, lines 24-51. Especially preferred of these compounds are 2-hydroxyethyl acrylate and 3-hydroxypropyl acrylate. Other preferred hydroxyalkyl acrylates are 2,2,2-tris(acryloyloxymethyl)ethanol and 2,3-di(acryloyloxy)propanol. Diisocyanates, Formula III, that can be used to react with the hydroxyalkyl acrylates and methacrylates to form isocyanatoacrylates and methacrylates are any of the well-known diisocyanates. Preferred diisocyanates are hexamethylene diisocyanate, toluene diisocyanate, and isophorone diisocyanate. The coating composition of the invention may be prepared by dissolving the polymerizable ethylenically-unsaturated sulfocompound in a suitable solvent. Water, aqueous-organic solvent, or an organic solvent can be used. Typically from 0.05 to 20 parts, preferably 0.2 to 4 parts, of solvent, preferably water, are used per part ethylenically-unsaturated sulfocompound. Examples of solvents that can be used include acetone, methyl ethyl ketone, methanol, aqueous methanol, aqueous ethanol, trichloroethylene, toluene, and the like. Other preferred solvents are the reactive solvents that are ethylenically-unsaturated and are copolymerizable with the ethylenically-unsaturated sulfocompound of the invention. Particularly preferred reactive solvents are the acrylic and methacrylic acid esters such as, for example, ethyl acrylate, butyl acrylate, n-octyl acrylate, allyl acrylate, cyclohexyl acrylate, N-methylcarbamoyloxyethyl acrylate, neopentylglycol diacrylate, 1,6-hexanediol diacrylate, pentaerythritol tetraacrylate, 1,3,5-tri(2-acryloyloxyethyl)isocyanurate, and the corresponding methacrylates. Depending on the particular application of the coating composition it may be desirable to include in the composition conventional antioxidants, thermal stabilizers or free radical inhibitors in order to prolong storage life of the composition. Examples of such materials are butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) commercially available as Ionox TM 220 (Shell), Santonox TM R (Monsanto), Irganox TM 1010 (Ciba-Geigy), etc. Generally, from 0.01 to 5.0 percent by weight of the total weight of the coating composition can be used. The properties of the coatings can be further modified by including in the coating composition a variety of adjuvants utilized for their known purpose, such as lubricants, plasticizers (e.g., dibutyl phthalate), tackifying resins (e.g., the copolymer of styrene and -methylstyrene), inorganic thickeners, fillers (e.g., organic and inorganic particles, fibers, and flakes), pigments, and dyes. Fillers can generally be used in proportions up to about 200 parts by weight per 100 parts by weight of copolymerizable components of the coating composition. When insoluble components are desired in the coating composition, it may be necessary to use conventional high speed dispersing apparatus such as paint mills, ball mills, and the like. Free radical generating compounds that can be used in the coating composition of the invention for effecting the conversion, on exposure to energy, of coatings prepared from the composition having ethylenically-unsaturated terminal groups, from a solvent-soluble, hydrophilic state to a solvent-insoluble, hydrophobic state, are materials known in the art. Particularly suitable free radical generating compounds include, for example, organic peroxides, azo compounds, aromatic diazonium salts, aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, quinones, benzophenones, nitroso compounds, acyl halides, aryl halides, hydrazones, mercapto compounds, pyrrylium compounds, triarylimidazoles, biimidazoles, and chloroalkyltriazines, These materials, in general, must have photosensitizers therewith to form a photoinitiator system useful with radiation above about 400 nm. Photosensitizers, such as spectrally absorbing dyes, are well known in the art. Typically the free radical generating compound is used at a concentration of 0.01 to 10 percent, preferably 0.05 to 5 percent, by weight of the total weight of the coating composition and the photosensitizer is used at a concentration of 10 percent to 100 percent by weight of the weight of the free radical generating compound. Additional reference in the art to free radical photoinitiator systems for ethylenically-unsaturated compounds are included in U.S. Patent No. 3,887,450 (e.g., col. 4), U.S. Patent No. 3,895,949 (e.g., col. 7), and U.S. Patent No. 4,043,819. Preferred initiators are the onium salts as disclosed in U.S. Patent Nos. 3,729,313; 4,058,400 and 4,058,401. Other desirable initiators are biimidazoles (disclosed in U.S. Patent No. 4,090,877) and chloroalkyltriazines as disclosed in U.S. Patent No. 3,775,113. These references also disclose sensitizers therein. Another good reference to photoinitiator systems is Light-Sensitive Systems , J. Kosar, J. Wiley and Sons, Inc. (1965), especially Chapter 5. The energy-curable compositions can be used to form crosslinked, adherent, abrasion-resistant coatings on substrates using substantially any technique known in the art including spraying, curtain coating, direct or reverse roll coating, dipping, brushing, extruding, and printing. However applied, the coating is allowed to dry to remove non-copolymerizable solvent, where used, and leave a hard tack-free coating that in the absence of applied energy, particularly actinic, remains soluble and can be removed from the substrate by treatment with a solvent, particularly water or an aqueous solvent such as aqueous methanol. The dried coating can be crosslinked by exposure to radiation for a sufficient time and intensity which may vary from about ten seconds to ten minutes or more depending on the thickness and particular composition of the coating. Substrates which may be coated with the crosslinkable compositions of the invention include organic substrates of wood, fiberboard, particle board, paper, and cardboard; synthetic and natural polymers such as polyesters, polyamides, cured phenolics, urea-aldehyde resins, poly(vinyl halides), polyacrylates, polyurethanes, proteins, rubber; inorganic substrates such as iron, stainless steel, copper, brass, bronze, aluminum, titanium, nickel, zinc, and alloys. Particularly useful substrates are silicated aluminum and the polyesters such as polyethyleneterephthalate and poly(vinyl chloride). The energy-curable coatings of the invention can have a thickness ranging from about 0.01 m to about 10.0 mm or more, preferably 0.1 to 1.0 mm. Suitable radiation for use in the crosslinking the coatings of the invention and rendering them insoluble include radiation at wavelengths in the 200 to 600 nm range, preferably 200 to 450 nm. Suitable sources include sunlight, carbon arcs, mercury-vapor arcs, black light lamps, fluorescent lamps, argon and xenon glow lamps, electronic flash units, and photographic flood lamps. Electron accelerators and electron beam sources may also be used. The energy-curable coating compositions of the invention, particularly when coated onto a substrate, are suitable for use in the graphic arts for the recording of information, e.g., color separation images, in printing plates and for use in the production of resist images, e.g., printed circuits. Objects and advantages of this invention are further illustrated by the following examples, EXAMPLE 1 Illustrating the preparation of a sulfopolyester urethane acrylate. Into a one liter 3-neck flask equipped with a mechanical stirrer, reflux condenser and drying tube, thermometer, and oil bath with temperature control, 130 g (0.1 mole) Sulfoester Polyol A (prepared as described below), was added to 50 g (0.2 mole) bis(4-isocyanatophenyl)methane, 0.03 g dibutyltin dilaurate, and 150 g methyl ethyl ketone. As stirring was initiated, the temperature began to rise. Additional heat was applied to raise the temperature of the contents of the flask to 60°C where it was held for 4 hours. There was then added 65 g pentaerythritol triacrylate and 500 ppm (with respect to the acrylate) of p-methoxy phenol. Stirring and heating was continued for an additional 4 hours at 60°C. The polymer was readily soluble in water from which it could be coated as a film and dried to a non-tacky coating that could be redissolved in water, sodium hydroxide solution, methanol, aqueous methanol, acetone, methylene chloride and other common organic solvents. The dried film had a calculated average molecular weight of 2400 and an acrylic group equivalent weight of about 400. A cleaned copper sheet was coated with a solution of 20 g of the above-described carbamate acrylate of Sulfoester Polyol A (designated Carbamate Acrylate I) and 0.2 g of benzoin ethyl ether in 80 ml of 20 percent methyl ethyl ketone in water and dried in the air to provide a coating 5 micrometers thick. The film was exposed through a mask to ultraviolet from a 20 watt black light lamp for 2 minutes. The unexposed areas were readily removed by washing with water, methanol or other common solvent. The presence of Urethane Acrylate I in exposed areas is readily detected by wiping the washed, exposed sheet with a dilute solution of a cationic dye wherein the exposed areas take on the color of the dye. Utility of the urethane acrylates of the invention as a resist material is illustrated by the fact that the copper sheet bearing the water developed image is undamaged by immersion into a Woods metal bath (this is a well known low temperature melting alloy of bismuth and a mixture of other metals) at 260°C for at least 30 seconds, is undamaged by a refluxing bath of HCl containing methanol, and will withstand a 30 percent ferric chloride copper etching bath without undercutting. Preparation of Sulfoester Polyol A A one liter 3-neck flask was equipped with a mechanical stirrer, a nitrogen purge, and set for vacuum distillation using a round-bottom flask which is cooled with a dry ice/acetone both for receiving distillate. A Woods metal bath was used to heat the 3-neck flask. Into the 3-neck flask was placed 148 g (0.5 mole) dimethyl 5-sulfiosophthalate, 530 g PCP-020O (1.0 mole of polycaprolactonediol having a weight average molecular weight of 530 available from Union Carbide Corp.), 0.13 g tetraisopropyl titanate (0.02 percent by weight) as esterification catalyst. Nitrogen purge and agitation were initiated. The contents of the flask were brought to 230°C and held for 4 hours during which time 50 to 75 percent of methanol condensate was removed. The pressure was reduced to 20 Torr and the temperature increased to 250°C and held for two hours. The system was then back filled with nitrogen and the low viscosity product removed from the flask while hot. It was found to have a hydroxyl equivalent weight of 650. EXAMPLE 2-9 Ethenically-unsaturated carbamate esters of sulfoester polyols were prepared by the procedure employed in EXAMPLE 1 using equivalent amounts of polyol and corresponding amounts of isocyanatoalkyl acrylates. The particular polyol and isocyanatoalkyl acrylate used to make the isocyanatoalkyl acrylate are given in TABLE I. Also given in TABLE I are the acrylic functionality and calculated acrylic equivalent weight of each urethane acrylate. EXAMPLE 10 Coating compositions of each Carbamate Acrylate II-IX were prepared in accordance with the procedure of EXAMPLE 1. To each composition was added 0.1 g of Methyl Violet 2 B Base and the composition was coated onto 75 m sheets of biaxially stretched poly(ethylene terephthalate) and dried in the air to provide a coating 5 micrometers thick. Each coating was exposed through a mask to ultraviolet light from a 20 watt black light at a distance of 8.9 cm (3.5 inches) for 5 minutes. The unexposed areas of the coating were readily removed by washing with water or aqueous methanol leaving a deep blue colored, tough abrasion-resistant coating of insoluble polymer in the exposed areas. EXAMPLE 11 A coating composition was prepared as described in EXAMPLE 1 and TABLE I from 20 g Carbamate Acrylate II, 2.0 g poly(vinyl pyrrolidone) available from GAF Corp., and 0.05 g Methyl Violet 20 Base (as image indiator) in 80 ml of 20 percent methyl ethyl ketone in water. 0.4 g of 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)- s -triazine (as disclosed in U.S. Patent No. 3,954,475) was used as a photoinitiator. This composition was coated on grained anodized aluminum using a squeeze roll coater and then dried. A coating weight of about 1.7 g per square meter was obtained. The coating was exposed in a vacuum frame to a carbon arc for 40 seconds through a neutral density filter and a negative. It was developed by wiping with aqueous methanol.

Claims: An ethylenically-unsaturated sulfocompound which is the poly(ethylenically-unsaturated ester or amide) of a sulfopolyol or sulfopolyamine comprising the reaction product provided by the following steps in sequence of: a. providing a sulfopolyol or sulfopolyamine which is the reaction product of 1) one mole of a sulfodicarboxylic acid and 2) about two moles of an aliphatic polyol having (c+1) hydroxyl groups attached to a saturated linear chain of up to 55 carbon atoms in units of 2 to 12 -CH₂ groups separated by 0 to 8 groups or about 2 moles of a polyamine having (c + 1) amine groups attached to a saturated linear chain of up to 55 carbon atoms in units of 2 to 12 -CH₂- groups separated by 0 to 22 -O- atoms and 0 to 8 groups, the polyol or polyamine having a molecular weight of less than 1000 and c being an integer of 1, 2, or 3 ; and b. reacting the resulting sulfopolyol or polyamine with 2 c moles of either 1), 2), or 3), in which 1) is a compound selected from (a) 2 alkenylazlactones having the formula wherein R is hydrogen or methyl; R¹ is a covalent bond, -CH₂- or -CH₂CH₂-, R² and R³ are independently hydrogen or methyl; and (b) ethylenically-unsaturated isocyanates having the formula wherein R⁴ is a covalent bond, -CH₂-, wherein R⁵ is a linear or branched chain of 1 to 12 carbon atoms optionally containing one catenary oxygen atom or group or R⁵ is a 5- or 6-membered carbocyclic group optionally substituted by lower alkyl groups having 1 to 4 carbon atoms, the carbocyclic group having a total of up to 12 carbon atoms, and R⁶ is an organic group selected from linear or branched alkylene groups having 2 to 12 carbon atoms, a cyclopentamethylene group, a cyclohexamethylene group, a 5-or 6-membered azacyclic group, a phenylene group, a naphthalene group, a phenylenemethylene-phenylene group, the organic group optionally substituted by up to four lower alkyl groups having 1 to 4 carbon atoms and a total of up to 15 carbon atoms; or 2) a diisocyanate having the formula the reaction product of said sulfopolyester polyol or polyamine and said diisocyanate then being reacted with 2 c moles of an ethylenically-unsaturated alcohol having the formula wherein R and R⁶ are as defined above; R⁷ is R⁸ is a polyvalent aliphatic group selected from linear and branched alkyl groups having a valence of (a + 1), 2 to 12 carbon atoms, no or one nonperoxidic catenary oxygen atom, and no or one group, and alicyclic groups having a 5- or 6-atom carbocyclic structure optionally substituted by up to 4 lover alkyl groups having 1 to 4 carbon atoms and a total of up to 12 carbon atoms, and a is an integer of 1, 2, or 3; or 3) the reaction product of one mole of organic diisocyanate of Formula III and one mole of an ethylenically-unsaturated alcohol of Formula IV; there being essentially no hydroxyl, amino, or isocyanate groups remaining after the reaction of a. with b.1), b.2), or b.3), wherein the ethylenically-unsaturated sulfocompound contains a single central sulfo group. An ethylenically unsaturated sulfocompound according to claim 1 wherein a) said polyol is selected from the reaction product of one mole of sulfodicaroxylic acid and about two moles of a polyol selected from the group consisting of poly(oxytetramethylene)diol, poly(oxyethylene)glycol, polycaprolactonepolyol, and pentaerythritol; b) said dicarboxylic acid is selected from 5-sulfoisophthalic acid, 3-sulfoglutaric acid, and sulfosuccinic acid; and c) said polyamine is selected from polyoxypropylene di- and triamines and polyoxyethylene di-and triamines. An ethylenically-unsaturated sulfocompound according to Claim 1 or Claim 2 having a formula selected from wherein: R, R⁶, R⁷, R⁸ and c are defined above; R⁹ is an arenetriyl (trivalent arene) group having 6 to 12 carbon atoms or an alkanetriyl (trivalent alkane) group having 2 to 12 carbon atoms remaining after the removal of carboxyl and sulfo groups from sulfoarene- and sulfoalkane dicarboxylic acids having the formula in which M is a cation; R¹⁰ is a linear aliphatic group having a valence of (c+1) consisting of a saturated chain of up to 55 carbon atoms in units of 2 to 12 -CH₂- groups separated by 0 to 22 -O- atoms and 0 to 8 groups, the aliphatic group having a molecular weight of less than 1000, wherein c is an integer having a value of 1, 2, or 3; R¹¹ is in which R¹, R², R³, and R⁴ are defined above; X is -O- or -NH-; and a is an integer of 1, 2, or 3. An enthylenically-unsaturated sulfocompound according to any of claims 1 to 3 wherein a) R⁴ is R¹⁰ is derived from a polycaprolactonepolyol or polyoxyalkylene-polyol having a molecular weight of up to 1000, and R⁹ is an arenetriyl group; b) said diisocyanate from which R⁶ is derived is selected from toluene diisocyanate, isophorone diisocyanate, and bis(4-isocyanatophenyl)methane; and c) R⁸ is a group selected from wherein e is an integer of 1 to 6 inclusively. A cured product resulting from curing the ethylenically-unsaturated sulfocompound according to any preceeding claim. A composition comprising the ethylenically-unsaturated sulfocompound according to any preceeding claim, an aqueous, aqueous-organic or organic solvent, and a source of free radicals. A composition according to Claim 6 wherein said solvent is selected from acrylic and methacrylic acid esters. An ethylenically-unsaturated sulfocompound according to any of claims 1 to 4 wherein R⁸ in said step b.2) is selected from in which e is an integer of 1 to 6 inclusively.-- An intermediate isocyanate-terminated sulfocompound comprising the reaction product provided by the following steps in sequence: a. providing a sulfopolyol or sulfopolyamine which is the reaction product of 1) one mole of a sulfodicarboxylic acid and 2) about two moles of an aliphatic polyol having (c+1) hydroxyl groups attached to a saturated linear chain of up to about 55 carbon atoms in units of 2 to 12 -CH₂ groups separated by 0 to 8 groups or about 2 moles a polyamine having (c + 1) amine groups attached to a saturated linear chain of up to 55 carbon atoms in units of 2 to 12 -CH₂- groups separated by 0 to 22 -O- atoms and 0 to 8 groups, the polyol and polyamine having a molecular weight of less than 1000 and c being an integer of 1, 2, or 3 ; and b. reacting the resulting sulfopolyol or polyamine with 2 c moles of a diisocyanate having the formula wherein R⁶ is an organic group selected from linear or branched alkylene groups having 2 to 12 carbon atoms, a cyclopentamethylene group, a cyclohexamethylene group, a 5- or 6-membered azacyclic group, a phenylene group, a naphthalene group, a phenylenemethylenephenylene group, the organic group optionally substituted by up to four lower alkyl groups having 1 to 4 carbon atoms and a total of up to 15 carbon atoms, to provide said isocyanate-terminated sulfocompound which has a single central sulfo group. The sulfocompound according to claim 1 which is the reaction product of a sulfopolyol or sulfopolyamine and a diisocyanate of formula III. A method of forming a coating on selected areas of a substrate comprising the steps of coating on said substrate a composition as claimed in claim 6 or claim 7 or a composition comprising a sulfocompound as claimed in any of claims 1 to 4 or 8 in combination with a source of free radicals, exposing the coating to radiation in imagewise fashion for a time sufficient to crosslink the exposed areas of the coating, and removing the unexposed portions of the coating with a solvent.

Inventors: LARSON, WAYNE KEITH C/O MINNESOTA MINING AND
Applicants: MINNESOTA MINING AND MANUFACTURING COMPANY
Application year: 1984
Main classification: C08G63
IPC codes: C08F299, C09D167, C08F2, C08G63, C08G18, C08F290, C08G69, C08L67