US008415437B2 (12) United States Patent (10) Patent N0.2 US 8,415,437 B2 Schwalm et a]. (45) Date of Patent: Apr. 9, 2013 (54) (METH)ACRYLATED MELAMINE 4,357,219 A * 11/1982 Sattler ........................... .. 522/92 FORMALDEHYDE RESINS 4,409,077 A * 10/1983 Sakiyama et a1. . 522/167 5,288,523 A * 2/1994 Klaiber et al. 427/385.5 . . _ 5,866,259 A * 2/1999 Harris et a1. 428/424.4 (75) Inventors: Reinhold SchWalm, Wachenhe1m (DE), 5,888,655 A * 3/1999 Harris et a1‘ 428/4231 Chrlstlne Roesch, Oppenhelm (DE) 6,777,458 B1* 8/2004 JaWorek et a1. ................. .. 522/1 7,164,037 B2 1/2007 Dietsche et a1. (73) Assignee: BASF SE, LudWigshafen (DE) 7,517,474 B2 4/2009 Wagner et a1~ 8,198,387 B2 * 6/2012 Kawada et a1. ............. .. 526/261 ( * ) Notice: Subject to any disclaimer, the term of this l Z; 311' patent is extended or adjusted under 35 ' U.S.C. 154(b) by 0 days. FOREIGN PATENT DOCUMENTS DE 19618 720 11/1996 (21) Appl. No.: 13/131,995 DE 196 51350 6/1998 DE 199 57 900 6/2001 (22) PCT Filed: Aug. 2, 2010 EP 0 007 508 2/1980 EP 0 057 474 8/1982 . EP 0 263 749 4/1988 (86) PCT No.. PCT/EP2010/061169 EP 0495 751 7/1992 § 371 (0X1) EP 0 615 980 9/1994 ’_ EP 0 675 141 10/1995 (2), (4) Date- May 31’ 2011 EP 0 738 740 10/1996 EP 198 26 712 12/1999 (87) PCT Pub. No.: W02011/015539 EP 199 13 353 9/2()()() JP 63 286426 ll/l988 PCT Pub. Date: Feb. 10, 2011 JP 2004122456 A * 4/2004 W0 98 33761 8/1998 (65) Prior Publication Data WO 2004 050888 6/2004 WC 2008 022922 2/2008 US 22, W0 2010 130608 11/2010 (30) Foreign Application Priority Data OTHER PUBLICATIONS Aug. 5, 2009 (EP) ................................... .. 09167273 Giacobbe, T1» et 91» “Syntheses Of Monomers from Hydmxyethyl Acrylate and Methylolmelamine Which PolymeriZe by Low Doses of (51) Int_ CL Radiation,” Macromolecules, vol. 4, No. 5, pp. 630-632, (Sep.-Oct. C08F 283/00 (2006.01) 1971)~ _ _ _ C08F 277/00 (200601) Internatlonal Search Report lssued Dec. 6, 2010 1n PCT/EP10/ C08F 271/02 (200601) 061169 ?led Aug. 2, 2010. C08F 271/00 (2006.01) * . . (52) U 5 Cl cited by examiner USPC ......... .. 525/518; 525/509; 525/519; 522/134; _ _ 1 d 522/135; 522/136; 522/144; 522/149; 522/151; Pr’mry Examl’qer * Sam‘ MCC ‘in on _ 522/162; 522/166; 522/167; 522/173; 522/178 (74) Alwmey] _ 486"’! 0? Flrm * 0121011, SPWak, (58) Field of Classi?cation Search ................ .. 522/134, Mcclenand, Male/r & Neustad" L-L-P 522/135,136,144,149,151,162,166,167, 522/173, 178, 182; 525/50, 509, 518, 519 (57) ABSTRACT See apphcanon ?le for Complete Search hlstory' The present invention relates to melamine-formaldehyde res (56) References Cited ins bearing (meth)acrylic groups, to processes for preparing them, to their use, and to coating compositions comprising them. U.S. PATENT DOCUMENTS 3,464,938 A * 9/1969 Nordstrom .................. .. 525/159 4,266,053 A 5/1981 Imanakaetal. 9 Claims, No Drawings US 8,415,437 B2 1 2 (METH)ACRYLATED MELAMINE molar melamine:formaldehyde:alcohol incorporation ratio of FORMALDEHYDE RESINS 1:3 to 5.4:2 to 4.3, is distinguished by a thermal reactivity Which is signi?cantly increased in comparison to the ?rst The present invention relates to melamine-formaldehyde group, Without acid catalysis. The production of these resins bearing (meth)acrylic groups, to processes for prepar crosslinkers is accompanied by self-condensation, leading to ing them, to their use, and to coating compositions compris a higher viscosity (loWer high-solids behavior) and making ing them. the removal of the free formaldehyde during distillation more Pigmented paints and transparent varnishes comprising or dif?cult as a result. For these products a free formaldehyde based on melamine-formaldehyde resins have been knoWn content of 0.5% to 1.5% is standard, though there are also for a number of decades. products having a free formaldehyde content of 0.3% to 3% UnplasticiZed melamine-formaldehyde resins serve, either by Weight. Here again, methylated and butylated commercial on their oWn or in combination With further, chemically dif products, and also grades With mixed etheri?cation, are Wide ferent crosslinkers, examples being blocked polyisocyanates, spread. Etheri?cation With other alkylating compounds is trisalkylcarbamoyltriaZines (TACT) or epoxides, as a described in the literature, and the corresponding products are crosslinking component in binder mixtures. Curing of the available as specialty products. ?lm-forming constituents produces a coating Which is resis High-imino grades and methylol grades, each as a sub tant to chemical, mechanical, and Weathering-induced in?u group, both feature incomplete methylolation, i.e., molar ences. PlasticiZed melamine-formaldehyde resins may fea formaldehyde incorporation ratios of less than 1:5.5. The ture modi?cations With carbamate structures, blends With high-imino grades differ from the methylol grades, hoWever, polyesters or alkyd resins, and/ or precondensations With the 20 in a high degree of alkylation, i.e., in the proportion of the latter. When used on ?exible coating substrates lacking etheri?ed methylol groups as a fraction of the incorporated dimensional stability, unplasticiZed melamine-formaldehyde formaldehyde equivalents, Which is usually up to 80%, resins require external elasti?cation in order for the coating Whereas for the methylol grades it is generally <70%. not to tear; as a sole formulating constituent, the crosslinker Applications for the partly methylolated melamine-form forms only brittle netWorks. 25 aldehyde resins extend across all ?elds of use, including Melamine-formaldehyde resins can be characterized combinations With HMMM grades, for adaptation of reactiv according to application (molding compounds, glues, ity, Where curing temperatures of 100 to 1500 C. are required. impregnating resins, coating materials), alkylating com Additional catalysis using Weak acids is possible and is com pounds (etheri?cation With butanol, methanol, mixed etheri mon practice. ?cation) or, as set out here, by the ratio of triaZine to formal 30 Besides the reaction of the amino resin With the binder dehyde to etherifying alcohol: there is a substantially increased proportion of self-crosslink 1. fully to highly methylolated and fully alkylated to highly ing on the part of the crosslinker. The consequence is reduced alkylated resins (HMMM grades) elasticity in the system as a Whole, and this reduction must be 2.1 partly methylolated and highly alkylated resins (high compensated by an appropriate selection of the co-compo imino grades) 35 nent. Set against this is the advantage of reduced total form 2.2. partly methylolated and partly alkylated resins (methylol aldehyde emission from the coatings produced from the sys grades) tem. 3. resins With a loW degree of methylolation (melamine Finishes based on melamine-formaldehyde condensation formaldehyde condensates) resins are used in the automotive segment, for industrial coat The ?rst major group of the fully etheri?ed melamine 40 ings generally, but also for Wood and plastic. The coating formaldehyde resins, in Which the molar melamine:formal systems feature particular hardness, gloss, resistance to dehyde:alcohol incorporation ratio is theoretically 1:6:6, in chemicals and to yelloWing, and Weather resistance. practice generally 1:>5.5:>5.0, and usually 1:>5.5:>4.0, is The reaction of melamine-formaldehyde resins With poly distinguished by extremely good high-solids behavior (rela mers containing carbamate groups is knoWn, as from EP tively loW viscosity at high solids content). In this group of 738740 or EP 675141, for example. crosslinkers the free formaldehyde is readily reducible. At the The copolymers described therein are obtained by free present time it is possible to achieve a free formaldehyde radical polymeriZation of acrylates and comonomers Which content<0.3% by Weight. The commercial products usually comprise a carbamate group and a (meth)acrylic group and comprise methanol as the alcohol, although grades With can then be reacted in conventional manner With amino res mixed etheri?cation, and fully butylated grades, are also 50 ins, for example, to form crosslinked ?lm-forming resins. knoWn. The preparation of comonomers of this kind Which bear a The fully etheri?ed melamine-formaldehyde resins are carbamate group and a (meth)acrylic group is knoWn from employed in practice preferably in can coating and coil coat WO 2004/050888 (corresponding to Us. Pat. No. 7,164, ing and for all coats of the automobile ?nish. 037), for example. The loW thermal reactivity under baking conditions, such 55 Their structural ?exibility makes melamine-formaldehyde as 20 minutes at 1400 C., necessitates catalysis With strong resins interesting starting compounds for radiation-curable acids for these fully etheri?ed melamine-formaldehyde res compounds. ins. This results in very rapid curing, and a homogeneous Reaction products of etheri?ed melamines With hydroxyl co-netWork as a result of transetheri?cation With the binder, acrylates are knoWn for application in radiation-curable coat accompanied by the release of the etherifying alcohols. With 60 ing compositions; see, for example, T. J. Giacobbe et al., this strong-acid catalysis, very short cure times are possible, Macromolecules, 4, 1971, 630 ff. or JP63286426. as in the case of partly methylolated melamine-formaldehyde The presence of acid-labile formals or N,O-acetals, hoW resins. Crosslinking may be accompanied by formaldehyde ever, makes such structures unstable in the acidic pH range, emission Which goes Well beyond the free formaldehyde and and this is manifested, for example, in lability under moisture is due to the re-cleavage of methylol groups. 65 exposure (see beloW). The second major group of the partly etheri?ed melamine U.S. Pat. No. 4,266,053 describes (meth)acrylates com formaldehyde resins, Which in practice generally feature a prising melamine rings, prepared as reaction products of US 8,415,437 B2 3 4 melamine-based polyols With (meth)acrylic acid, for use in incorporated by reference to become part of the present UV-curing coatings oniamong othersiplastics parts. description, or in the German patent application With the Although they feature better moisture resistance than the application number 1020090030352 and the ?ling date of compounds described by T. J. Giacobbe et al. (see compara May 12, 2009 (corresponding to the international patent tive example 1 in table 1 of Us. Pat. No. 4,266,053), their application With the application number PCT/EP2010/ preparation is necessarily complicated, on the basis of cya 056079 and the application date of May 5, 2010, and also to the Us. patent application Ser. No. 12/ 776,670 and the appli nuric chloride. cation date of May 10, 2010). It Was an object of the present invention to provide neW, Following compounds of the formula (I) are preferred: radiation-curable compounds based on melamine-formalde Y is preferably 1,2-ethylene, 1,2-propylene, 1,3-propy hyde resins that are stable to re-cleavage over a broad pH lene, more preferably 1,2-ethylene and 1,2-propylene, and range, and are simple to prepare. very preferably 1,2-propylene. This object has been achieved by means of radiation-cur Examples of R3 and/or R4 are hydrogen, methyl, ethyl, able compounds obtainable by reacting at least one isopropyl, n-propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, melamine-formaldehyde resin With at least one compound of n-hexyl, n-heptyl, n-octyl, n-decyl, n-dodecyl, n-tetradecyl, the formula (I), n-hexadecyl, n-octadecyl, n-eicosyl, 2-ethylhexyl, cyclopen tyl, cyclohexyl, cyclooctyl, cyclododecyl, 2-hydroxyethyl, 2-hydroxypropyl, 1 -hydroxypropyl, 5 -hydroxy-3 -oxa-pen O O tyl, 8-hydroxy-3,6-dioxaoctyl or 1 1-hydroxy-3,6,9-trioxaun R3\ III 1 O/ Y \O)KK decyl. 20 R3 and/or R4 is preferably hydrogen, methyl, ethyl, isopro pyl, n-butyl, tent-butyl, and cyclohexyl, more preferably hydrogen, methyl, ethyl, n-butyl, and tert-butyl, very prefer ably hydrogen, methyl or ethyl, more particularly hydrogen in Which R3 and R4 independently of one another are hydrogen, 25 or methyl, and especially both radicals are hydrogen. Preferably the alcohols (C) are selected from the group Cl-Cl8 alkyl, C6-Cl2 aryl or C5-Cl2 cycloalkyl, consisting of 2-hydroxyethyl carbamate, 2-hydroxy-1-propyl Y is selected from 1,2-ethylene, 1,2-propylene, 1,1-dim ethyl-1,2-ethylene, 1-hydroxymethyl-1,2-ethylene, 2-hy carbamate and 3-hydroxy-2-propyl carbamate. The latter are droxy-1,3-propylene, 1,3-propylene, 1,4-butylene, 1,6-hexy used preferably in the form of an isomer mixture. lene, 2-methyl-1,3-propylene, 2-ethyl-1,3-propylene, 2,2 30 A melamine-formaldehyde resin in the context of the present speci?cation is the reaction product of melamine, dimethyl-1,3-propylene, and 2,2-dimethyl-1,4-butylene, or formaldehyde, and, if desired, at least one alcohol, preferably of melamine, formaldehyde, and one or tWo alkanols, more preferably melamine, formaldehyde, and an alkanol. With 35 very particular preference the alkanols are selected from the group consisting of methanol, ethanol, n-butanol, isobutanol, and secondary-butanol, preferably selected from the group consisting of methanol, n-butanol, and isobutanol; more pref or 1,2-, 1,3- or 1,4-cyclohexylene, erably they are methanol and/or n-butanol, and very prefer R1 is hydrogen or methyl, preferably hydrogen, 40 ably methanol or n-butanol. With the proviso that at least one of the radicals R3 and R4 The melamine-formaldehyde resin is preferably a com is hydrogen. pound of the formula The compounds of the formula (I) can be prepared prefer ably by esterifying alcohols (C) containing urethane groups 45 in Which Mel-N3 is a melamine radical formed by imaginary (C) abstraction of the six hydrogen atoms attached to the amino o groups in melamine, R3 i Y H PA is a group 4CH24Oi, \III 0/ \O/ 50 R5 is a Cl-C8 alkyl group. R5 in accordance With the invention is one or more different R4 Cl-C8 alkyl groups, preferably a Cl-C4 alkyl group, prefer ably a methyl, ethyl or butyl group, very preferably a methyl With (meth)acrylic acid or With a (meth)acrylic ester, pref group or an n-butyl group, more particularly a methyl group. erably a (meth)acrylic acid alkyl ester, more preferably a 55 Cl-C8 alkyl groups are for example methyl, ethyl, n-pro (meth)acrylic acid alkyl ester Whose alkyl radical contains 1 pyl, isopropyl, n-butyl, isobutyl, 2-butyl, tert-butyl, 1-pentyl, to 8 carbon atoms. 2-pentyl, isoamyl, n-hexyl, n-octyl or 2-ethylhexyl. One possible preferred preparation of such alcohols (C) C 1 -C4 alkyl for the purposes of this speci?cation is methyl, containing urethane groups is described in WO 2004/ 050888, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 2-butyl or tert page 3 line 26 to page 7 line 23 (corresponding to Us. Pat. 60 butyl. No. 7,164,037, column 2 line 56 to column 5 line 33), Which Butanol for the purposes of this speci?cation refers collec is hereby incorporated by reference to become part of the tively to n-butanol, isobutanol, sec-butanol, and mixtures present description. thereof, preferably n-butanol or isobutanol, and more prefer One possibility for the preparation of the compounds of the ably n-butanol. formula (I) is described in WO 2004/050888, page 8 line 7 to 65 fA can adopt any desired values from 3.6 to a maximum of page 11 line 38 (corresponding to Us. Pat. No. 7,164,037, 6.0. Preferably fA is at least 4.1, more preferably at least 4.2, column 5 line 57 to column 8 line 34), Which is hereby and very preferably at least 5.0. US 8,415,437 B2 5 6 Generally speaking, fA adopts values of preferably a maxi The free formaldehyde content is more particularly not mum of 6.0, more preferably not more than 5.8, very prefer more than 0.2% and especially not more than 0.15% by ably not more than 5.6, and more particularly not more than Weight, and in individual cases is not more than 0.1% by 5.4. Weight. On the basis of a consideration of the fundamentals, mA The free formaldehyde content is determined in accor cannot be greater than fA . dance With EN ISO 11402. For example, mA adopts values of at least 2.0, preferably at Information on the resin distribution according to polymer least 2.4, more preferably at least 2.9, and very preferably at de?nition is provided by gel permeation chromatography least 3.4. (GPC) and by GPC/MS coupling. The resins may comprise Generally speaking, mA is not greater than 5.0, preferably dimers and trimers and also higher oligomers, up to a mass not greater than 4 .9, more preferably not greater than 4 .8, and fraction of 90%. very preferably not greater than 4.7. The compounds of the invention are obtainable by a reac The formula Mel-N3 FAfA RSMA H67“ is considered a tion of melamine-formaldehyde resins With (meth)acrylates description in general form and is calculated from the resin bearing carbamate groups, Which proceeds preferably at analyses Without taking account of any bridges formed by acidic pH: condensation. Starting from total nitrogen, determined by The reaction takes place at a pH of not more than 6.0, means of elemental analysis, the melamine content in the preferably not more than 5.0, more preferably not more than resin structure is calculated and is standardized as Mel-N3:1. 4.5, very preferably betWeen 1 and 4, and more particularly The incorporated formaldehyde is calculated as total formal 20 betWeen 1 and 3. dehyde (determined folloWing acid digestion) minus the free Suitable acidic catalysts are sulfuric acid, nitric acid, phos formaldehyde (DIN 16746-A, sul?te method), on a molar phoric acid, hydrochloric acid, para-toluenesulfonic acid, basis based on melamine. This is the number fA . The incor benZenesulfonic acid, dodecylbenZenesulfonic acid, meth porated alcohol is determined from the difference betWeen anesulfonic acid or mixtures thereof; acidic ion exchangers the total alcohol content, according to gas chromatography 25 are also conceivable. Preference is given to sulfonic acids, after acid digestion, and the free alcohol content according to particular preference to para-toluenesulfonic acid, benZene gas chromatography, on a molar basis based on melamine. sulfonic acid, dodecylbenZenesulfonic acid, methanesulfonic In one preferred embodiment of the present invention, in acid or mixtures thereof. the melamine-formaldehyde resin employed, of the methylol The acidic catalyst Will be added generally in amounts of groups that are present in the molecule, introduced by form 30 0.1% to 10%, preferably 0.5% to 7.5%, more preferably 1% aldehyde, Whose number is given by fA , there are generally at to 6%, and very preferably 3% to 5%, by Weight. It may be least 50% that are etheri?ed by groups R5, and so mA§0.5><fA, sensible to introduce the catalyst in tWo or more portions. preferably at least 55%, more preferably at least 60%, and The molar stoichiometric ratio betWeen the compound of more preferably at least 65%. the formula (I) and melamine-formaldehyde resin employed 35 Generally speaking, not more than 99% are etheri?ed by (based on melamine units in the melamine-formaldehyde groups R5, and so mA§0.99><fA, preferably not more than resin) in the reaction is generally from 10:1 to 1:1, preferably 95%, more preferably not more than 90%, and very prefer from 8:1 to 1.5:1, more preferably from 6:1 to 2:1. If the ably not more than 87%. intention is that some of the compound of the formula (I) For the above-mentioned HMMM grades, hoWever, it is should not react during the reaction, it may remain unreacted 40 entirely possible for all methylol groups to be etherifed, and and Without separation in the reaction mixture, and may func so for these resins it is the case that mAIfA. tion as a reactive diluent. The solids content of the melamine-formaldehyde resin In accordance With the invention it is unimportant Whether employed has no part to play in accordance With the inven the compound of the formula (I) is introduced ?rst and the tion. The solids content may be, for example, at least 50%, 45 melamine-formaldehyde resin added, or the melamine-form preferably at least 60%, more preferably at least 70%, and aldehyde resin is introduced ?rst in a part of the compound of very preferably at least 75%, by Weight. the formula (I), and the remainder of the compound of the In general the solids content Will not exceed 98%, and With formula (I) is added continuously or in portions, or the preference Will not exceed 97%. melamine-formaldehyde resin is introduced ?rst and then the The solids content is determined in accordance With ISO 50 compound of the formula (I) is added. 3251, by spreading out 2 g of the sample material and 2 ml of The temperature in the reaction ranges generally from n-butanol in a Well-ventilated drying cabinet for a duration of room temperature to 1500 C., preferably from 50 to 1300 C., 2 hours With heating at 125° C. For the calculation, the sample more preferably from 60 to 120° C., and very preferably from is Weighed before and after, and the ratio provides the solids 70 to 100° C. 55 content. The reaction time during the transetheri?cation is from 10 The melamine-formaldehyde resin employed may com minutes to 6 hours. prise at least one solvent, examples being Water, C l-C4 alkyl The number-average molar weight M” of the resultant, alcohols, such as methanol, ethanol, isopropanol, n-propanol, inventively modi?ed melamine-formaldehyde resins is gen n-butanol, isobutanol, sec-butanol or tert-butanol, for erally less than 2000 g/mol, preferably less than 1500 g/mol, 60 example, or aromatic hydrocarbons, such as toluene or else and more preferably less than 1300 (determined by gel per xylene isomer mixtures, for example. meation chromatography With tetrahydrofuran and polysty The free formaldehyde content of the melamine-formalde rene as standard, DIN 55672, Part 1). hyde resin employed is generally not more than 1.5% by In one preferred embodiment the acid number of the result Weight; for example, it may be not more than 1.0%, prefer 65 ant melamine-formaldehyde resins is less than 20, more pref ably not more than 0.6%, more preferably not more than erably less than 15, and very preferably less than 10 mg 0.5%, and very preferably not more than 0.3%, by Weight. KOH/ g, determined in accordance With ISO 3682. US 8,415,437 B2 7 8 In one preferred embodiment the color number of the (Cyclo)aliphatic hydrocarbons are for example decalin, resultant melamine-formaldehyde resins is less than 200, alkylated decalin, and isomer mixtures of linear or branched more preferably less than 1 50, determined in accordance With alkanes and/or cycloalkanes. DIN EN 1557. Of further preference are n-butyl acetate, ethyl acetate, The free formaldehyde content as per EN ISO 1 1402 in the 1-methoxyprop-2-yl acetate, 2-methoxyethyl acetate, and resultant melamine-formaldehyde resins is generally not also mixtures thereof, especially With the aromatic hydrocar bon mixtures set out above. more than 0.5%, preferably not more than 0.3%, more pref Mixtures of this kind may be produced in a volume ratio of erably not more than 0.1%, and very preferably not more than 0.05% by Weight. 10:1 to 1:10, preferably in a volume ratio of 5:1 to 1:5, and more preferably in a volume ratio of 1:1, not counting any The modi?ed melamine-formaldehyde resin obtained in solvents still present in the reaction mixture from the accordance With the invention may subsequently be mixed transetheri?cation, and more particularly the alcohols RSOH With commonplace solvents. and R6OH. Examples of such solvents are aromatic and/or (cyclo) Preferred examples are butyl acetate/xylene, 1:1 methox aliphatic hydrocarbons and mixtures thereof, halogenated ypropyl acetate/xylene, 1:1 butyl acetate/ solvent naphtha hydrocarbons, esters, ethers, and alcohols. 100, 1:2 butyl acetate/Solvesso® 100, and 3:1 Kristalloel Preference is given to aromatic hydrocarbons, (cyclo)ali 30/Shellsol® A. phatic hydrocarbons, alkanoic acid alkyl esters, alkoxylated Alcohols are for example methanol, ethanol, n-propanol, alkanoic acid alkyl esters, and mixtures thereof. isopropanol, n-butanol, sec-butanol, isobutanol, pentanol iso Particular preference is given to mono- or polyalkylated 20 mer mixtures, hexanol isomer mixtures, 2-ethylhexanol or benZenes and naphthalenes, alkanoic acid alkyl esters and octanol. alkoxylated alkanoic acid alkyl esters, and mixtures thereof. Also conceivable, though less preferred, is Water, espe Preferred aromatic hydrocarbon mixtures are those com cially When used With other organic solvents as solubiliZers in prising predominantly aromatic C7 to C14 hydrocarbons and a mixture. being able to encompass a boiling range from 1 10 to 300° C.; 25 The amount of the resultant melamine-formaldehyde res particular preference is given to toluene, o-, m- or p-xylene, ins in the solvents after mixing can be in general up to 98% by trimethylbenZene isomers, tetramethylbenZene isomers, eth Weight, based on the sum of melamine-formaldehyde resin ylbenZene, cumene, tetrahydronaphthalene, and mixtures and solvent, preferably up to 95%, more preferably up to comprising them. 90%, very preferably up to 86%, and more particularly up to 80%, by Weight. Examples thereof are the Solvesso® grades from Exxon 30 In one preferred embodiment of the present invention the Mobil Chemical, especially Solvesso® 100 (CAS No. 64742 modi?ed melamine-formaldehyde resins obtainable in accor 95-6, predominantly C9 and C10 aromatics, boiling range dance With the invention are prepared in a reactive diluent about 154-178° C.), 150 (boiling range about 182-207° C.), and/ or mixed With such diluents after their preparation. and 200 (CAS No. 64742-94-5), and also the Shellsol® 35 Reactive diluents of this kind are at least one, for example grades from Shell. Hydrocarbon mixtures of para?ins, cyclo one to three, preferably one to tWo, and more preferably just paraf?ns, and aromatics are also available commercially one compound Which contains at least one, preferably at least under the Kristalloel names (for example, Kristalloel 30, tWo, free-radically polymeriZable, preferably radiation-cur boiling range about 158-198° C. or Kristalloel 60: CAS No. able groups, for example tWo to six, preferably tWo to four, 64742-82-1), White spirit (for example likeWise CAS No. 40 and more preferably tWo to three. 64742-82-1) or solvent naphtha (light: boiling range about The reactive diluents preferably have a loW viscosity of, 155-180° C., heavy: boiling range about 225-300° C.). The preferably, less than 15 000 mPas (at 25° C. in accordance aromatics content of hydrocarbon mixtures of this type is With DIN EN ISO 3219/A.3). generally more than 90%, preferably more than 95%, more The reactive diluents have an average molecular Weight of preferably more than 98%, and very preferably more than up to 1000, preferably up to 750 g/mol. The compounds in 99%, by Weight. It may be sensible to use hydrocarbon mix question are preferably polyether (meth)acrylate or a (meth) tures having a particularly reduced naphthalene content. acrylate of a diol, triol or tetraol, or a urethane di(meth) The density at 20° C. to DIN 51757 of the hydrocarbons acrylate based on a diisocyanate. can be less than 1 g/cm3, preferably less than 0.95 and more Particularly preferred reactive diluents have a boiling point preferably less than 0.9 g/cm3 . 50 of more than 200° C. under atmospheric pressure. The aliphatic hydrocarbons content is generally less than The reactive diluents may for example be reactive diluents 5%, preferably less than 2.5%, and more preferably less than of the kind described generally in P.K.T. Oldring (editor), 1%, by Weight. Chemistry & Technology of UV & EB Formulations for Halogenated hydrocarbons are for example chlorobenZene Coatings, Inks & Paints, Vol. II, Chapter III: Reactive Dilu and dichlorobenZene or its isomer mixtures. 55 ents for UV & EB Curable Formulations, Wiley and SITA Esters are for example n-butyl acetate, ethyl acetate, Technology, London 1997. 1-methoxyprop-2-yl acetate, and 2-methoxyethyl acetate, Examples of reactive diluents With a free-radically poly and also the monoacetyl and diacetyl esters of ethylene gly meriZable group are methyl acrylate and methyl methacry col, diethylene glycol, triethylene glycol, propylene glycol, late. dipropylene glycol or tripropylene glycol, such as, for Preferred reactive diluents are the diesters and polyesters example, butylglycol acetate. Further examples are also car of (meth)acrylic acid With diols or polyols. Particularly pre bonates, such as preferably 1,2-ethylene carbonate, 1,2-pro ferred are hexanediol diacrylate, hexanediol dimethacrylate, pylene carbonate or 1,3-propylene carbonate. octanediol diacrylate, octanediol dimethacrylate, nonanediol Ethers are for example tetrahydrofuran (THF), dioxane, diacrylate, nonanediol dimethacrylate, decanediol diacrylate, and also the dimethyl, diethyl or di-n-butyl ethers of ethylene 65 decanediol dimethacrylate, pentaerythrityl tetraacrylate, glycol, diethylene glycol, triethylene glycol, propylene gly dipentaerythrityl tetraacrylate, dipentaerythrityl triacrylate, col, dipropylene glycol or tripropylene glycol. pentaerythrityl tetraacrylate, etc. Also preferred are the esters US 8,415,437 B2 9 10 of alkoxylated polyols, With 0t,[3-ethylenically unsaturated The present invention further provides coating composi monocarboxylic and/or dicarboxylic acids, such as, for tions Which comprise example, the polyacrylates or polymethacrylates oftrimethy at least one radiation-curable compound according to the lolpropane, glycerol or pentaerythritol With on average three present invention, fold to 20-fold, preferably three fold to 15-fold, more prefer if desired, at least one reactive diluent, ably three fold to nine fold alkoxylation, especially ethoxy if desired, at least one solvent, lation, and also of diethylene glycol, triethylene glycol, dipro if desired, further, typical coatings additives, and pylene glycol or tripropylene glycol. Suitability is also at least one photoinitiator. Examples of further, typical coatings additives Which can possessed by the esters of alicyclic diols, such as cyclohex be used include antioxidants, stabiliZers, activators (acceler anediol di(meth)acrylate and bis(hydroxymethyl)cyclohex ants), ?llers, pigments, dyes, antistats, ?ame retardants, ane di(meth)acrylate. thickeners, thixotropic agents, surface-active agents, viscos With particular preference the reactive diluent is selected ity modi?ers, plasticiZers or chelating agents. from the group consisting of ethylene glycol di(meth)acry Suitable thickeners, in addition to free-radically (co)poly late, diethyleneglycol di(meth)acrylate, triethylene glycol meriZed (co)polymers, include customary organic and inor di(meth)acrylate, butanediol di(meth)acrylate, hexanediol ganic thickeners such as hydroxylmethylcellulose or bento di(meth)acrylate, trimethylolpropane mono-, di- or tri (meth) nite. acrylate, pentaerythrityl mono-, di-, tri- or tetra(meth)acry Examples of chelating agents Which can be used include late, and 2,2-bis-4-(2-hydroxy-3-methacryloyloxy)phenyl ethylene diamine acetic acid and salts thereof, and also propane. 20 [3-diketones. A further embodiment of the present invention uses, as Suitable ?llers comprise silicates, examples being silicates reactive diluents, reaction products, free from NCO groups, obtainable by hydrolysis of silicon tetrachloride, such as of aliphatic or aromatic diisocyanates and (meth)acrylic Aerosil® from Degussa, siliceous earth, talc, aluminum sili esters Which carry isocyanate-reactive groups, preferably OH cates, magnesium silicates, calcium carbonates, etc. groups. Use may be made, for example, of reaction products 25 Suitable stabiliZers comprise typical UV absorbers such as of aliphatic or aromatic diisocyanates and hydroxyethyl oxanilides, triaZines, and benZotriaZole (the latter available as (meth)acrylate, hydroxypropyl (meth)acrylate or hydroxybu Tinuvin® grades from Ciba-SpeZialitatenchemie), and ben tyl (meth)acrylate. Preferred diisocyanates are are 2,4'- and Zophenones. These can be used alone or together With suit able free-radical scavengers, examples being sterically hin 4,4'-diphenylmethane diisocyanate (MDI), 2,4- or 2,6 tolylene diisocyanate (TDI), tetramethylene diisocyanate, 30 dered amines such as 2,2,6,6-tetramethylpiperidine, 2,6-di tert-butylpiperidine or derivatives thereof, e.g., bis(2,2,6,6 hexamethylene diisocyanate, 2,4'- and 4,4'-methylenebis(cy tetramethyl-4-piperidyl)sebacate. Stabilizers are used clohexyl)diisocyanate, xylylene diisocyanate, tetrameth typically in amounts of 0. 1 % to 5.0% by Weight, based on the ylxylylene diisocyanate, dodecyl diisocyanate, lysine alkyl solid components present in the formulation. ester diisocyanate, Where alkyl is C1 to C10, 2,2,4- or 2,4,4 trimethyl-1,6-hexamethylene diisocyanate, 1,4-diisocyana 35 Pigments may likeWise be included. Pigments, according to CD Rompp Chemie LexikoniVersion 1.0, Stuttgart/New tocyclohexane, 1,3- or 1,4-bis(isocyanatomethyl)cyclohex York: Georg Thieme Verlag 1995, With reference to DIN ane, triisocyanatotoluene, isophorone diisocyanate (IPDI), 55943, are particulate “organic or inorganic, chromatic or 2-butyl-2-ethylpentamethylene diisocyanate, 2-isocyanato achromatic colorants that are virtually insoluble in the appli propylcyclohexyl isocyanate, 3(4)-isocyanatomethyl-1-me 40 cation medium”. thylcyclohexyl isocyanate, 1,4-diisocyanato-4-methylpen Virtually insoluble here means a solubility at 250 C. beloW tane, or and 2- or 4-methylcyclohexane 1,3-diisocyanate 1 g/ 1000 g of application medium, preferably beloW 0.5, (H-TDI), or mixtures of the aforementioned isocyanates. more preferably beloW 0.25, very preferably beloW 0.1, and Particularly preferred are reaction products of aliphatic more particularly beloW 0.05 g/ 1000 g of application diisocyanates, such as tetramethylene diisocyanate, hexam 45 medium. ethylene diisocyanate, 2,4'- and 4,4'-methylenebis(cyclo Where a pigment is used, it is necessary to ensure either hexyl)diisocyanate, xylylene diisocyanate, tetramethylxy that the curing is carried out With electron beams or that a lylene diisocyanate, dodecyl diisocyanate, lysine alkyl ester photoinitiator is used Which can be activated by the irradiated radiation in spite of the pigmentation; for example, by the diisocyanate, Where alkyl is C1 to C10, 2,2,4- or 2,4,4-trim ethyl-1,6-hexamethylene diisocyanate, 1,4-diisocyanatocy 50 photoinitiator having a signi?cant absorption in a Wavelength range in Which the pigment is suf?ciently transparent for the clohexane, 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane, irradiated radiation. One preferred embodiment of the present isophorone diisocyanate (IPDI), 2-butyl-2-ethylpentameth ylene diisocyanate, 2-isocyanatopropylcyclohexyl isocyan invention uses no pigment and uses the coating composition in clearcoat materials. ate, 3 (4)-isocyanatomethyl- 1 -methylcyclohexyl isocyanate, 55 Examples of pigments comprise any desired systems of 1,4-diisocyanato-4-methylpentane, or and 2- or 4-methylcy absorption pigments and/or effect pigments, preferably clohexane 1,3-diisocyanate (H-TDI), and hydroxyethyl absorption pigments. There are no restrictions Whatsoever on (meth)acrylate, hydroxypropyl (meth)acrylate or hydroxybu the number or selection of the pigment components. They tyl (meth)acrylate. Especially preferred are reaction products may be adapted as desired to the particular requirements, such of hexamethylene diisocyanate, isophorone diisocyanate, 60 as, for example, to the desired perceived color. 2,2,4- or 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, Effect pigments are all pigments Which exhibit a platelet and hydroxyethyl methacrylate, hydroxypropyl methacrylate shaped construction and impart speci?c decorative color or hydroxybutyl methacrylate, and also, especially, the reac effects to a surface coating. The effect pigments comprise, for tion product of 2,2,4- and/or 2,4,4-trimethyl-1,6-hexameth example, all of the effect-imparting pigments Which can be ylene diisocyanate and tWo equivalents of hydroxyethyl 65 employed commonly in vehicle ?nishing and industrial coat methacrylate, as knoWn under the trivial name urethane ing. Examples of effect pigments of these kinds are pure metal dimethacrylate or UDMA. pigments, such as aluminum, iron or copper pigments; inter US 8,415,437 B2 11 12 ference pigments, such as titanium dioxide-coated mica, iron Also suitable are nonyelloWing or loW-yelloWing photoini oxide-coated mica, mixed oxide-coated mica (e. g., With tita tiators of the phenylglyoxalic ester type, as described in nium dioxide and Fe2O3 or titanium dioxide and Cr2O3), DE-A 198 26 712, DE-A 199 13 353 or WO 98/33761. metal oxide-coated aluminum, or liquid-crystal pigments. Typical mixtures comprise, for example, 2-hydroxy-2-me The color-imparting absorption pigments are, for example, thyl-1-phenylpropan-2-one and 1-hydroxycyclohexyl phenyl ketone, bis(2,6-dimethoxybenZoyl)-2,4,4-trimethyl-pen customary organic or inorganic absorption pigments Which tylphosphine oxide and 2-hydroxy-2-methyl-1-phenylpro can be used in the coatings industry. Examples of organic pan-1-one, benZophenone and l-hydroxycyclohexyl phenyl absorption pigments are aZo pigments, phthalocyanine pig ketone, bis(2,6-dimethoxybenZoyl)-2,4,4-trimethylpen ments, quinacridone pigments, and pyrrolopyrrole pigments. tylpho sphine oxide and 1-hydroxycyclohexyl phenyl ketone, Examples of inorganic absorption pigments are iron oxide 2,4,6-trimethylbenZoyldiphenylphosphine oxide and 2-hy pigments, titanium dioxide, and carbon black. droxy-2-methyl-1 -phenylpropan- 1 -one, 2,4, 6-trimethylben Where the coating compositions are cured not With elec Zophenone and 4-methylbenZophenone or 2,4,6-trimethyl tron beams but instead by means of UV radiation, there is benZophenone and 4-methylbenZophenone and 2,4,6 preferably at least one photoinitiator present Which is able to trimethylbenZoyldiphenylphosphine oxide. initiate the polymerization of ethylenically unsaturated Preferred among these photoinitiators are 2,4,6-trimethyl double bonds. benZoyldiphenylphosphine oxide, ethyl 2,4,6-trimethylben Photoinitiators may be, for example, photoinitiators Zoylphenylphosphinate, bis(2,4,6-trimethylbenZoyl)-phe knoWn to the skilled Worker, examples being those speci?ed nylphosphine oxide, benZophenone, 1 -benZoylcyclohexan- 1 - in “Advances in Polymer Science”, Volume 14, Springer Ber 20 ol, 2-hydroxy-2,2-dimethylacetophenone, and 2,2 lin 1974 or in K. K. Dietliker, Chemistry and Technology of dimethoxy-2-phenylacetophenone. UV and EB Formulation for Coatings, Inks and Paints, Vol The coating compositions comprise the photoinitiators ume 3; Photoinitiators for Free Radical and Cationic Poly preferably in an amount of 0.05% to 10% by Weight, more meriZation, P. K. T. Oldring (editor), SITA Technology Ltd, preferably 0.1% to 8% by Weight, and more particularly 0.2% London. 25 to 5% by Weight, based on the total amount of the curable Suitability is possessed for example by monoacyl- or bisa components. cylphosphine oxides, as described, for example, in EP-A 7 The coating materials can be employed in particular in 508, EP-A 57 474, DE-A 196 18 720, EP-A 495 751 or EP-A primers, surfacers, pigmented topcoat materials and clearcoat 615 980, examples being 2,4,6-trimethylbenZoyldiphe materials in the ?eld of automotive re?nish, large-vehicle nylphosphine oxide (Lucirin® TPO from BASF SE), ethyl 30 ?nishing, and aircraft. Coating materials of this kind are 2,4,6-trimethylbenZoylphenylphosphinate (Lucirin® TPO L particularly suitable for applications requiring particularly from BASF SE), bis(2,4,6-trimethylbenzoyl)phenylphos high levels of application reliability, external Weathering phine oxide (lrgacure® 819 from Ciba SpeZialitatenchemie), resistance, hardness, and ?exibility, such as in automotive benZophenones, hydroxyacetophenones, phenylglyoxylic re?nish and large-vehicle ?nishing. acid and its derivatives, or mixtures of these photoinitiators. 35 Coating compositions, comprising the by the inventively Examples include benZophenone, acetophenone, acetonaph obtainable mixtures are especially employed as or in automo thoquinone, methyl ethyl ketone, valerophenone, hexanophe tive clearcoat and topcoat material(s). Further preferred ?elds none, ot-phenylbutyrophenone, p-morpholinopropiophe of use are can coating and coil coating. none, dibenZosuberone, 4-morpholinobenZophenone, Coil coating is the continuous coating of metal strips With 4-morpholinodeoxybenZoin, p-diacetylbenZene, 4-ami coating materials, usually liquid coating materials. Rolled 40 nobenZophenone, 4'-methoxyacetophenone, [3-methylan metal strips, after production, are Wound up into rolls (re thraquinone, tert-butylanthraquinone, anthraquinonecar ferred to as “coils”) for the purposes of storage and transport. boxylic esters, benZaldehyde, ot-tetralone, These metal strips represent the starting material for the 9-acetylphenanthrene, 2-acetylphenanthrene, 10-thioxan majority of sheetlike metallic Workpieces, examples being thenone, 3-acetylphenanthrene, 3-acetylindole, 9-?uo 45 automobile parts, bodyWork parts, instrument paneling, exte renone, 1-indanone, 1,3,4-triacetylbenZene, thioxanthen-9 rior architectural paneling, ceiling paneling or WindoW pro one, xanthen-9-one, 2,4-dimethylthioxanthone, 2,4 ?les, for example. For this purpose the appropriate metal diethylthioxanthone, 2,4-diisopropylthioxanthone, 2,4 sheets are shaped by means of appropriate techniques such as dichlorothioxanthone, benZoin, benZoin isobutyl ether, punching, drilling, folding, pro?ling and/or deep draWing. chloroxanthenone, benZoin tetrahydropyranyl ether, benZoin 50 Larger components, such as automobile bodyWork parts, for methyl ether, benZoin ethyl ether, benZoin butyl ether, ben example, are assembled optionally by Welding together a Zoin isopropyl ether, 7H-benZoin methyl ether, benZ[de]an number of individual parts. thracen-7-one, 1-naphthaldehyde, 4,4'-bis(dimethylamino) For the coating operation, metal strips With a thickness of benZophenone, 4-phenylbenZophenone, 4-chloro 0.2 to 2 mm and a Width of up to 2 m are transported at a speed benZophenone, Michler’s ketone, l-acetonaphthone, 55 of up to 200 m/min through a coil coating line, and are coated 2-acetonaphthone, 1 -benZoyl-cyclohexan-1-ol, 2-hydroxy-2, in the process. For this purpose it is possible to use, for 2-dimethylacetophenone, 2,2-dimethoxy-2-phenylacetophe example, cold-rolled strips of soft steels or construction none, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichlorac grade steels, electrolytically galvanized thin sheet, hot-dip etophenone, 1 -hydroxy-ac etophenone, ac etophenone galvaniZed steel strip, or strips of aluminum or aluminum dimethyl ketal, o-methoxybenZophenone, triphenylphos 60 alloys. Typical lines comprise a feed station, a coil store, a phine, tri-o-tolylphosphine, benZ[a]anthracene-7,12-dione, cleaning and pretreatment Zone, a ?rst coating station along 2,2-diethoxyacetophenone, benZil ketals, such as benZil dim With baking oven and doWnstream cooling Zone, a second ethyl ketal, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholi coating station With oven, laminating station, and cooling, nopropan- 1 -one, anthraquinones such as 2-methylan and also a coil store and Winder. thraquinone, 2-ethylanthraquinone, 2-tert 65 Characteristic of coil coatings are thin ?lms of the coating butylanthraquinone, 1 -chloroanthraquinone, compositions, With a dry ?lm thickness of usually Well beloW 2-amylanthraquinone, and 2,3-butanedione. 80 um, often beloW 60 um, beloW 50 um, and even beloW 40 US 8,415,437 B2 13 14 um. Furthermore, the metal sheets are processed With a high The method of coating substrates can also be practiced by throughput, Which necessitates short residence times, i.e., irradiating the applied coating composition of the invention, necessitates drying at an elevated temperature following or paint formulations, ?rst With electron beams or UV expo application of the coating, in order that the coating composi sure, under oxygen or, preferably, under inert gas, in order to tion soon acquires load-bearing qualities. obtain preliminary curing, then carrying out thermal treat Coating of the substrates With the coating compositions ment at temperatures up to 1600 C., preferably betWeen 60 takes place in accordance With typical processes knoWn to the and 1600 C., and subsequently completely curing With elec skilled Worker, a coating composition or a paint formulation tron beams or UV exposure under oxygen or, preferably, comprising it being applied in the desired thickness to the under inert gas. target substrate and, optionally, dried. This operation may if Optionally, if a plurality of layers of the coating material desired be repeated one or more times. Application to the are applied one on top of another, drying and/or radiation substrate may take place in a knoWn Way, as for example by curing may take place after each coating operation. spraying, troWeling, knifecoating, brushing, rolling, roller Examples of suitable radiation sources for the radiation coating, pouring, laminating, injection backmolding or coex cure are loW-pressure, medium-pressure, and high-pressure truding. mercury lamps, and also ?uorescent tubes, pulsed lamps, Further disclosed is a method of coating substrates Which metal halide lamps, electronic ?ash devices, Which alloW involves applying to the substrate a coating composition or a radiation curing Without a photoinitiator, or excimer lamps. paint formulation comprising it, admixed optionally With fur The radiation cure is accomplished by exposure to high ther, typical coatings additives and thermally, chemically or energy radiation, i.e., UV radiation or daylight, preferably radiation-curable resins, drying the applied coating option 20 light emitted in the Wavelength range of 7t:200 to 700 nm, ally, curing it With electron beams or UV exposure under an more preferably 7t:200 to 500 nm, and very preferably 7t:250 oxygen-containing atmosphere or, preferably, under inert to 400 nm, or by irradiation With high-energy electrons (elec gas, and subjecting it to thermal treatment, optionally, at tron radiation; 150 to 300 keV). Examples of radiation temperatures up to the level of the drying temperature, and sources used include high-pressure mercury vapor lamps, thereafter at temperatures up to 160° C., preferably betWeen 25 lasers, pulsed lamps (?ash light), halogen lamps or excimer 60 and 1600 C., more preferably betWeen 100 and 1600 C. lamps. The radiation dose typically su?icient for crosslinking Radiation curing takes place With high-energy light, UV in the case of UV curing is situated in the range from 80 to light for example, or electron beams. Radiation curing may 3000 mJ/cm2. take place at relatively high temperatures. Preference is given It Will be appreciated that it is also possible to use tWo or in that case to a temperature above the T8 of the radiation 30 more radiation sources for the cure, tWo to four for example. curable binder. These sources may also each emit in different Wavelength Radiation curing here means the free-radical polymeriza ranges. tion of polymeriZable compounds as a result of electromag Drying and/or thermal treatment may also take place, in netic and/or particulate radiation, preferably UV light in the addition to or instead of the thermal treatment, by means of Wavelength range of 7t:200 to 700 nm and/ or electron radia 35 NIR radiation, Which here refers to electromagnetic radiation tion in the range from 150 to 300 keV, and more preferably in the Wavelength range from 760 nm to 2.5 um, preferably With a radiation dose of at least 80, preferably 80 to 3000 from 900 to 1500 nm. mJ/cm2. Irradiation can if desired also be carried out in the absence Besides radiation curing there may also be further curing of oxygen, such as under an inert gas atmosphere. Suitable mechanisms involved, examples being thermal curing, mois 40 inert gases are preferably nitrogen, noble gases, carbon diox ture curing, chemical curing and/ or oxidative curing, prefer ide, or combustion gases. Furthermore, irradiation may take ably thermal and radiation curing, and more preferably radia place With the coating composition being covered With trans tion curing alone. parent media. Examples of transparent media are polymeric The coating materials may be applied one or more times by ?lms, glass or liquids, Water for example. Particular prefer any of a very Wide variety of spraying methods, such as 45 ence is given to irradiation in the manner described in DE-Al compressed-air, airless or electrostatic spraying methods, 199 57 900. using one- or tWo-component spraying units, or else by inject Suitable substrates for the coating compositions of the ing, troWeling, knifecoating, brushing, rolling, roller coating, invention are, for example, thermoplastic polymers, more pouring, laminating, injection backmolding or coextruding. particularly polymethyl methacrylates, polybutyl methacry The coating thickness is generally in a range from about 3 50 lates, polyethylene terephthalates, polybutylene terephtha to 1000 g/m2 and preferably 10 to 200 g/m2. lates, polyvinylidene ?uorides, polyvinyl chlorides, polyes Drying and curing of the coatings take place generally ters, polyole?ns, acrylonitrile-ethylene-propylene-diene under standard temperature conditions, i.e., Without the coat styrene copolymers (A-EPDM), polyetherimides, ing being heated. Alternatively the mixtures of the invention polyetherketones, polyphenylene sul?des, polyphenylene can be used to produce coatings Which, folloWing application, 55 ethers or mixtures thereof. are dried and cured at an elevated temperature, e.g., at Mention may additionally be made of polyethylene, 40-250o C., preferably 40-150o C., and more particularly at polypropylene, polystyrene, polybutadiene, polyesters, 40 to 1000 C. This is limited by the thermal stability of the polyamides, polyethers, polycarbonate, polyvinyl acetal, substrate. polyacrylonitrile, polyacetal, polyvinyl alcohol, polyvinyl Additionally disclosed is a method of coating substrates 60 acetate, phenolic resins, urea resins, melamine resins, alkyd Which involves applying the coating composition of the resins, epoxy resins or polyurethanes, their block copolymers invention or paint formulations comprising it, optionally or graft copolymers, and blends thereof. admixed With thermally curable resins, to the substrate, dry Mention may be made With preference of ABS, AES, ing it, and then curing it With electron beams or UV exposure AMMA,ASA, EP, EPS, EVA, EVAL, HDPE, LDPE, MABS, under an oxygen-containing atmosphere or, preferably, under 65 MBS, MF, PA, PA6, PA66, PAN, PB, PBT, PBTP, PC, PE, inert gas, optionally at temperatures up to the level of the PEC, PEEK, PEI, PEK, PEP, PES, PET, PETP, PF, PI, FIB, drying temperature. PMMA, POM, PP, PPS, PS, PSU, PUR, PVAC, PVAL, PVC, US 8,415,437 B2 15 1 6 PVDC, PVP, SAN, SB, SMS, UF, UP plastics (abbreviations nonvolatiles content (as per ISO 3251) of 93-96% by Weight, according to DIN 7728), and aliphatic polyketones. With a loW free formaldehyde content of not more than 0.3% Particularly preferred substrates are polyole?ns, such as, by Weight. The viscosity (ISO 3219 B) is 2.0-6.0 Pas at 23° C. for example, PP (polypropylene), Which may be alternatively and a shear rate D of41.3 s_l. isotactic, syndiotactic or atactic and alternatively unoriented HPC acrylate is the formal reaction product of 2-hydrox or oriented by monoaxial or biaxial stretching, SAN (styrene ypropyl carbamate (isomer mixture of 2-hydroxy-1-propyl acrylonitrile copolymers), PC (polycarbonates), PVC (poly carbamate and 3-hydroxy-2-propyl carbamate) With acrylic vinyl chlorides), PMMA (polymethyl methacrylates), PBT acid. The purity of the HPC acrylate Was at least 90% by (poly(butylene terephthalate)s), PA (polyamides), ASA Weight, the amount of unacrylated 2-hydroxypropyl carbam (acrylonitrile-styrene-acrylic ester copolymers) and ABS ate being beloW 5% by Weight, and the remainder being (acrylonitrile-butadiene-styrene copolymers), and also their unreacted acrylates. physical mixtures (blends). Particular preference is given to Erichsen cupping and scratch resistance. PP, SAN, ABS, ASA, and also blends of ABS orASA With PA The pendulum damping Was determined in accordance or PBT or PC. Very particular preference is given to polyole With DIN 53157. The pendulum damping is a measure of the ?ns, PMMA, and PVC. hardness of the coating. High values in this test denote high Especially preferred is ASA, more particularly in accor hardness. dance With DE 196 51 350, and the ASA/PC blend. Prefer The Erichsen cupping Was determined in accordance With ence is likeWise given to polymethyl methacrylate (PMMA) DIN 53156. The Erichsen cupping is a measure of the ?ex or impact-modi?ed PMMA. ibility and elasticity. It is reported in millimeters (mm). High A further-preferred substrate for coating With the coating 20 values denote high ?exibility. compositions of the invention are metals, Which if desired The residual gloss Was determined using the Scotch-Brite may have been pretreated With a primer. test after storage for 7 days in a controlled-climate chamber. The nature of the metal is in principle arbitrary. More In the Scotch-Brite test, a ?ber Web modi?ed With silicon particularly, hoWever, the metal comprises those metals or carbide and measuring 3><3 cm (Scotch Brite SUFN, from alloys Which are commonly used as metallic materials of 25 3M) is a?ixed as the test element to a cylinder. The cylinder construction, and Which require protection from corrosion. presses the ?ber Web against the coating With a de?ned The surfaces in question are more particularly those of applied Weight, and is moved over the coating pneumatically. iron, steel, Zn, Zn alloys, Al or Al alloys. These may be the The path length of the de?ection is 7 cm.After 10 or 50 double surfaces of bodies consisting Wholly of said metals/alloys. rubs (DR), the gloss is measured in the middle region of the HoWever, it is also possible for the bodies to be only coated 30 exposure (eight-fold determination) in a method based on With these metals and for the bodies themselves to be com DIN 67530 With an incidence angle of 20°. The residual gloss posed of different kinds of materials, as for example of other value in percent is given by the ratio of gloss after expo sure to metals, alloys, polymers or composites. The surfaces in ques initial gloss. High residual gloss values, i.e., loW values for the tion may be surfaces of castings of galvaniZed iron or steel. In loss of gloss, denote high scratch resistance. one preferred embodiment of the present invention the sur 35 faces are steel surfaces. Example 1 Zn alloys or Al alloys are knoWn to the skilled Worker. The skilled Worker selects the nature and amount of alloying Preparation of Melamine Carbamate Hydroxypropyl constituents in accordance With the desired application. Typi Acrylate in Bulk, Atmospheric Pressure cal constituents of Zinc alloys comprise, in particular, Al, Pb, 40 The thoroughly mixed initial charge of 65.1 g of LuWipal Si, Mg, Sn, Cu or Cd. Typical constituents of aluminum alloys 66, 173.17 g of HPC acrylate and 0.1732 g of methylhydro comprise, in particular, Mg, Mn, Si, Zn, Cr, Zr, Cu or Ti. The quinone is admixed at room temperature With 1 .19 g of meth alloys may also be Al/Zn alloys, in Which Al and Zn are anesulfonic acid. This system is heated to an external tem present in approximately equal amounts. Steel coated With perature of 90° C., While air is bubbled through it. At an alloys of this kind is available commercially. The steel may 45 internal temperature of 85° C., methanol distillation is com comprise the customary alloying components knoWn to the menced. After the end of reaction, a product of high viscosity skilled Worker. With a double bond density of 4.11 mol/kg is obtained. Also conceivable is the use of the coating compositions of the invention for the treatment of tin-plated iron/steel (tin Example 2 plate). 50 The coating compositions and paint formulations of the In Bulk, Reduced Pressure invention are additionally suitable for coating substrates such The thoroughly mixed initial charge of 65.1 g of LuWipal as Wood, paper, textile, leather, nonWoven, plastics surfaces, 66, 173.17 g of HPC acrylate and 0.1732 g of methylhydro glass, ceramic, mineral construction materials, such as quinone is admixed at room temperature With 1 .19 g of meth cement moldings and ?ber-cement slabs, or coated or 55 anesulfonic acid and 0.012 g of phenothiaZine. Heating takes uncoated metals, preferably plastics or metals, more particu place at a pressure of about 300 mbar up to an external larly in the form of ?lms or foils, With particular preference temperature of 90° C. At an internal temperature of 65° C., metals. methanol distillation commences. After the end of reaction, a The examples Which folloW are intended to illustrate the highly viscous product having a double bond density of 4.08 properties of the invention, but Without restricting it. 60 mol/kg is obtained. EXAMPLES Example 3 Unless indicated otherWise, “parts” in this speci?cation are Dilution With HDDA to be understood as “parts by Weight”. 65 The thoroughly mixed initial charge of 52.1 g of LuWipal LuWipal® 066LF from BASF SE is a highly to fully 66, 138.5 g of HPC acrylate and 0.01 g of phenothiaZine is methyl-etheri?ed melamine-formaldehyde resin having a admixed at room temperature With 1.9 g of methanesulfonic US 8,415,437 B2 17 1 8 acid. Under a pressure of about 300 mbar, heating takes place 21) to an external temperature of 90° C. At an internal tempera using a four-path frame-type Wet ?lm applicator With a gap ture of 690 C., methanol distillation commences. After the end depth of 300 um, Was applied to a glass substrate. After the of reaction, the batch is diluted to a solids content of 80% by solvent had been ?ashed (1 5 minutes at room temperature, 20 addition of 47.7 g of hexanediol diacrylate. minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 (high-pressure Hg lamp) at room temperature in a nitrogen Example 4 atmosphere. Cured ?lm: Pendulum damping: 178 sec Residual gloss after 10DR With 250 g applied Weight: Dilution With BuAc 83.2% The thoroughly mixed initial charge of 52.1 g of LuWipal Residual gloss after 50DR With 250 g applied Weight: 66, 138.5 g of HPC acrylate and 0.01 g of phenothiaZine is 70.0% admixed at room temperature With 1.9 g of methanesulfonic b) acid. Under a pressure of about 300 mbar, heating takes place using a four-path frame-type Wet ?lm applicator With a gap to an external temperature of 900 C. At an internal tempera depth of 400 um, Was applied to a glass substrate. After the ture of 690 C., methanol distillation commences. After the end solvent had been ?ashed (1 5 minutes at room temperature, 20 of reaction, the batch is diluted to a solids content of 80% by minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 addition of 47.7 g of butyl acetate. (hi gh-pres sure Hg lamp) at room temperature in an air atmo Use in UV-Curable Coatings sphere. Cured ?lm: A formulation of 75% by Weight of melamine carbamate Pendulum damping: 135 sec hydroxypropyl acrylate from example 1, 25% by Weight of 20 Residual gloss after 10DR With 250 g applied Weight: butyl acetate and 4% of lrgacure® 184 (Ciba SpeZialita 54.3% tenchemie, l-hydroxycyclohexyl phenyl ketone) Was pre Residual gloss after 50DR With 250 g applied Weight: pared and 74.0% 21) C) using a four-path frame-type Wet ?lm applicator With a gap 25 using a four-path frame-type Wet ?lm applicator With a gap depth of 300 um, Was applied to a glass substrate. After the depth of 150 um, Was applied to a Bonder panel. After the solvent had been ?ashed (15 minutes at room temperature, 20 solvent had been ?ashed (1 5 minutes at room temperature, 20 minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 (high-pressure Hg lamp) at room temperature in a nitrogen (high-pressure Hg lamp) at room temperature in a nitrogen atmosphere. Cured ?lm: 30 atmosphere. Cured ?lm: Pendulum damping: 189 sec Erichsen cupping: 1.4 mm Residual gloss after 10DR With 250 g applied Weight: (11) 90.9% using a four-path frame-type Wet ?lm applicator With a gap Residual gloss after 50DR With 250 g applied Weight: depth of 200 um, Was applied to a Bonder panel. After the 82.6% 35 solvent had been ?ashed (1 5 minutes at room temperature, 20 b) minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 using a four-path frame-type Wet ?lm applicator With a gap (hi gh-pres sure Hg lamp) at room temperature in an air atmo depth of 400 um, Was applied to a glass substrate. After the sphere. Cured ?lm: solvent had been ?ashed (15 minutes at room temperature, 20 Erichsen cupping: 0.9 mm minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 A formulation of 70% by Weight of melamine carbamate (hi gh-pres sure Hg lamp) at room temperature in an air atmo hydroxypropyl acrylate (prepared according to example 1), sphere. Cured ?lm: 30% by Weight of hexanediol diacrylate and 4% of lrgacure® Pendulum damping: 138 sec 184 Was prepared and Residual gloss after 10DR With 250 g applied Weight: 21) 62.3% 45 using a four-path frame-type Wet ?lm applicator With a gap Residual gloss after 50DR With 250 g applied Weight: depth of 300 um, Was applied to a glass substrate. After the 60.8% solvent had been ?ashed (1 5 minutes at room temperature, 20 C) minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 using a four-path frame-type Wet ?lm applicator With a gap (high-pressure Hg lamp) at room temperature in a nitrogen depth of 150 um, Was applied to a Bonder panel. After the atmosphere. Cured ?lm: solvent had been ?ashed (15 minutes at room temperature, 20 Pendulum damping: 174 sec minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 Residual gloss after 10DR With 250 g applied Weight: (high-pressure Hg lamp) at room temperature in a nitrogen 93.8% atmosphere. Cured ?lm: Residual gloss after 50DR With 250 g applied Weight: Erichsen cupping: 1.1 mm 55 89.6% d) b) using a four-path frame-type Wet ?lm applicator With a gap using a four-path frame-type Wet ?lm applicator With a gap depth of 200 um, Was applied to a Bonder panel. After the depth of 400 um, Was applied to a glass substrate. After the solvent had been ?ashed (15 minutes at room temperature, 20 solvent had been ?ashed (1 5 minutes at room temperature, 20 minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 minutes at 800 C.), the ?lm Was exposed With 1900 mJ/cm2 (hi gh-pres sure Hg lamp) at room temperature in an air atmo (hi gh-pres sure Hg lamp) at room temperature in an air atmo sphere. Cured ?lm: sphere. Cured ?lm: Erichsen cupping: 0.9 mm Pendulum damping: 191 sec A formulation of 80% by Weight of melamine carbamate Residual gloss after 10DR With 250 g applied Weight: hydroxypropyl acrylate (prepared according to example 2), 68.3% 20% by Weight of butyl acetate and 4% of lrgacure® 184 Was Residual gloss after 50DR With 250 g applied Weight: prepared and 32.8%