Alkyd resins are commonly used for solvent-based or water based coating systems.

Alkyd resins are formed through the incorporation of unsaturated fatty acid esters into polyester or polyurethane chain-extended polymer systems. Curing is obtained via auto- oxidative crosslinking.

Conventional alkyd resin systems contain a solvent, an anti skinning agent and a siccative.

The solvent will usually be an organic solvent.

Examples of antiskinning agents may be classified as antioxidants, blocking agents, solvents or retention agents. The European Patent Publication EP 1 103 583A1 describes aldoximes or ketoximes as antiskinning agents.

The cure-process involves oxidation, i. e. reaction with oxygen from the air. It is always performed in the presence of a catalyst, usually called a"drier"or"siccative", which is usually a combination of metal salts. Those catalysts are well-known in the art and commercially available. Examples of suitable driers are metal salts of (cyclo) aliphatic, natural or synthetic acids, such as, for example, linoleic acid, naphthenic acid and 2-ethyl-hexanoic acid. Cobalt, manganese, lead, zirconium, calcium and zinc are suitable metals. Mixtures of driers can, of course, also be used. In terms of their metal content, the driers are used in a proportion of 0.001 to about 3% by weight, relative to the binder solids content.

It has been suggested to replace the solvent by reactive diluents which are usually compounds or mixtures of compounds of relatively low viscosity, a relatively high boiling point (i. e. low saturated vapor pressure) which act as solvents during the formulation and processing of the coating. Such reactive diluents can co-polymerize with a resin thereby reducing losses of the solvent to atmosphere on drying of the coating.

WO 9702230 describes the use of 2- (2, 7-octadienoxy) di- (2, 7-octadienyl) succinate as a reactive diluent in a paint or coating formulation.

WO 9800387 describes the use of a composition comprising a mixture of a fumarate, maleate and 2-allyloxy-succinate esters as a reactive diluent in a paint-or coating formulation.

EP 072 127 describes an alkyd resin system containing a reactive diluent selected from the group consisting of dicyclopentenyl methacrylate and dicyclopentenyloxyalkyl methacrylate.

Japanese Patent Application JP2001226466A2 describes the polymerization of norbornene in the presence of allyl methacrylate and bis (tricyclohexylphosphine) benzylidene ruthenium dichloride to give methacryloyl-terminated polymers. Low viscous compounds are not described.

There is still a need to provide cobalt-free alkyd resin systems having a markedly reduced solvent content or being solvent free and showing a similar drying performance.

It has now been found that the compounds of formula la-le as defined below can be used as reactive diluents thus, replacing the solvent completely or partially.

The invention relates to compounds of the formula la-le wherein Ri and R2 independently of one another are hydrogen, hydroxy, cyano, halogen, vinyl, formyl, a residue of acrylic acid, C1-C6alkoxycarbonyl, Ci-C6alkylaminocarbonyl, phenylcarbonyl, Ci-C6alkylcarbonyloxy, Ci-C6alkenylcarbonyloxy, (meth) acryloyloxy, (meth) acryloylCl-C6alkylamino, di [(meth) acryloylC1-C6alkyliamino, unsubstituted C1-Cl2alkyl or Ci-Cl2alkyl substituted by hydroxy, halogen, ethynyl, Ci-C6alkylamino, di (C1-C6) alkylamino, (meth) acryloyloxy, (meth) acryloylCl-C6alkylamino, di [ (meth)- acryloylCi-C6aikyl]-amino or by tolylaminocarbonyloxy ; Rs is (meth) acryloyloxy-C1-C6alkyl or phenyl substituted once or more than once by hydroxy, halogen, cyano, vinyl, Ci-Cl2alkyl, Ci-C6alkoxy, phenoxy, benzyloxy, acetoxy, Ci-C6alkoxycarbonyloxy, Ci-C6alkylcarbonyloxy, trifluormethyl, (meth) acryloyloxy, (meth) acryloylC,-C6alkylamino, di [(meth)acryloylC1-C6alkyl] amino; or R3 is 1-naphthyl, 2-naphthyl, biphenyl, anthracenyl ; or R3 is a substituted phenyl residue of the formula -C6H4-CH2-W, wherein W signifies hydroxy, halogen, cyano, acetoxy, acetylsulfanyl, trifluormethylcarbonyloxy, (meth) acryloyloxy, (meth) acryloylCl-C6alkylamino, di [(meth)acryloylC1-C6alkyl] amino, Ci-C12alkoxy, C1-Cl2alkoxy substituted once or more than once by fluor, Ci-Cl2alkoxy substituted by epoxyethyl ; or W is dimethylamino, dimethylammonium, or W is a residue selected from an amino butyric acid or from an an £-caprolactame, or W is sulfonato, C1-C6alkylsulfonyl or C1-C6alkylsulfanyl, wherein the alkyl group is un- substituted or substituted by chlorine ; or W is a silanol residue or a residue of a phosphonic acid; R4 is hydrogen, phenyl, 1-naphthyl, 2-naphthyl, biphenyl, anthracenyl, phenyl substituted once or more than once by hydroxy, halogen, cyano, vinyl, Ci-Ci2alkyl, C1-C6alkoxy, phenoxy, benzyloxy, acetoxy, C1-C6alkoxycarbonyloxy, C1-C6alkylcarbonyloxy, trifluormethyl, (meth) acryloyloxy, (meth) acryloylCi-C6alkyl- amino, di [ (meth) acryloylCl-C6alkyl] amino, or R4 is a substituted phenyl residue of the formula-C6H¢CH2-W, wherein W signifies hydroxy, halogen, cyano, acetoxy, acetylsulfanyl, trifluormethylcarbonyloxy, (meth) acryloyloxy, (meth) acryloylCi-C6alkylamino, di [(meth)acryloylC1-C6alkyl] amino, C1-C12alkoxy, C1-C12alkoxy substituted once or more than once by fluor, C1-C12alkoxy substituted by epoxyethyl ; or W is dimethylamino, dimethylammonium, or W is a residue selected from an amino butyric acid or from an an £-caprolactame, or W is sulfonato, C1-C6alkylsulfonyl or Ci-Ceaikyisuifanyi, wherein the alkyl group is un- substituted or substituted by chlorine ; or W is a silanol residue or a residue of a phosphonic acid; or R4 is an aliphatic residue of the formula-(CR6R7) mY-A, wherein R6 and R7 independently of one another are hydrogen, C1-C12alkyl or phenyl ; m is 1-10, Y is a bond, O-C1-C12alkylene, wherein the alkylen linker is linear or branched and may be interrupted once or more than once by oxygen, A is hydroxy, C1-C6alkoxy, phenoxy, phenylcarbonyloxy, formyloxy, acetoxy, benzoyloxy, (meth) acryloyloxy, (meth) acryloyl-Ci-C6alkyl- amino, di [(meth)acryloylC1-C6alkyl] amino; or a phthalate-or maleat- residue; or R4 is a residue of the formula A or B R5 is hydrogen or Ci-C6alkyl ; n is a number of 1-10; X is -(CH2)1-4-, -CR8R9-, -CO-, -O-, -NR10-, -S-, R8 and R9 independently of one another are hydrogen, unsubstituted C-C6-alkyl or Cy-C6-alkoxy, C1-C6-alkyl substituted by OH, C1-C6-alkoxy or halogen ; unsubstituted aryl or aryl substituted by C1-C4-alkyl, OH, C1-C6alkoxy or halogen ; or Ci-Cgatkytcarbonytoxy or phenylcarbonyl- oxy, Rio is hydrogen, unsubstituted C1-C6-alkyl or C1-C6-alkyl substituted by OH-or C1-C4alkoxy ; unsubstituted phenyl or phenyl substituted by OH-, C1-C4alkyl- or C1-C4alkoxy.

Furthermore, the invention relates to a coating composition comprising (1) an alkyd resins, (2) a photoinitiator, (3) a reactive diluent of formula la-le as described above or mixtures thereof, and (4) optionally a solvent.

Definitions : Alkvd resin Alkyd resins are well known in the art and are readily available commercially.

Examples of resins that may be present include alkyd resins, epoxy-esters, urethane-alkyds and further modified oils.

Air drying alkyd resins are esters from drying oils, such as linseed oil, soybean oil, tungoil and other oils having unsaturated groups in there alkyl chain.

The alkyd resins can be classified as"long oil"alkyd resins containing more than 60 wt % of oil portion"medium oil"alkyd resins containing from 40 to 60wt% of oil portion and"short oil" alkyd resins containing less than 40 wt % of oil portion. The alkyd resins are described in Ullmann's Encyclopedia, 6"edition 1999.

Longoil alkyd resins are especially known as good dispersing resins for a wide variety of pigments.

The resin may be present in an amount of between 5 and 50wt%, based on the weight of the liquid coating composition. In high solid systems the resin is present in an amount >50wt%.

The alkyd may also be a water dilutable alkyd resins obtained by mixing (unmodified) alkyd resins with emulsifiers or may be a self-emulsifying alkyd resins with an chemically incorporated emulsifier.

Solvent Solvents used in alkyd resins are aliphatic, cycloaliphatic and aromatic hydrocarbons such as mineral spirits known as white spirit, as well as xylene, toluene, alcohol ethers, glycol ethers, ketones, esters, alcohol ether acetates or mixtures thereof. As mentioned above, the solvent is not necessary to perform the inventive coating.

Photoinitiator Any photoinitiator known to be useful for curing ethylenically unsaturated polymerizable compounds with daylight or with light sources equivalent to daylight or with UV-light may be used. The radiation employed is guided essentially by the absorption of the photoinitiators used. Suitable radiation sources are known. They can, for example, comprise lamps or lasers. Suitable UV lamps are mercury vapor lamps or UV lasers. The period of irradiation depends on the nature of the light source; it can range from seconds to minutes. Preference is given to the use of daylight.

Suitable photoinitiators are selected from benzophenones, benzophenone derivates such as, for example, halomethyl benzophenones, acetophenones, acetophenone derivates such as, for example, dialkoxyacetopheno, nes, halomethylacetophenones, a-hydroxy-or a-amino- acetophenones (1-benzoyl-1-hydroxy-1-methylethane or (4-morpholino-benzoyl)-2-benzoyl- 2-dimethylamino-propane or (4-methylthio-benzoyl)-1-methyl-1-morpholinoethane), α-sulfonyl acetophenones; halomethylarylsulfones, 4-aroyl-1, 3-dioxolanes, anthracene derivatives, thioxanthone derivatives, 3-ketocumarine derivatves, anthraquinone derivatives, benzoin alkylethers and benzil ketals, phenylglyoxalates and derivates thereof, dimeric phenylglyoxalates, peresters, monoacylphosphinoxides, bisacylphosphinoxides, trisacyl- phosphinoxides, halomethyltriazines, titanocenes, borates, O-acyloximes or camphor quinones. The photoinitiators may be used alone or in combination with suitable co-initiators.

Especially suitable are coating compositions comprising 0.3 to 10 wt. % of a mono-, bis-or trisacylphosphinoxide photoinitiator of the formula I X is 0 or S ; R1 and R2 independently of one another are linear or branched C1-C12-alkyl, Ci-C12-alkoxy, phenyl, unsubstituted or optionally substituted by OR8, SR9, NRtoR11 C1-C12-Alkyl or halogen ; or R, and R2 are phenyl-C1-C4-alkyl or R3 and R7 independently of one another are C1-Ci2-alkyl, C1-C12-alkoxy or halogen ; R4, R5 and R6 independently of one another are hydrogen, C1-C12-alkyl, C1-C12-alkoxy or halogen ; R8, R9 Rio and Rn independently of one another are hydrogen, C1-C12-alkyl, C2-C12-alkenyl, benzyl or C2-C20-alkyl interrupted once or several times by -O-; or Rio and RI, represent together with the N-atom that they are attached to an optionally oxygen-or-NR, 2-containing 5 or 6 membered ring; R12 is hydrogen, phenyl-C,-C4-alkyl or C-Cr2-alkyl.

Preferred are compounds of the formula I' Ri and R2 independently of one another are C-C8-alkyl, C1-C6-alkoxy, phenyl that is unsubstituted or optionally substituted by one or two OR8 or NR10R11; or R1 is and R2 is Ci-C12-alkyl or phenyl unsubstituted or optionally substituted by ORB ; R3 and R7 independently of one another are Ci-C4-alkyl, Ci-C4-alkoxy, or chlorine ; R4, R5 and R6 independently of one another are hydrogen or Ci-C4-alkyl, R8 is C1-C8-alkyl ; Rio and R11 represent together with the N-atom that they are attached to an optionally oxygen-containing 5 or 6 membered ring.

Especially preferred are compounds of the formula 1', in which R1 and R2 independently of one another are C1-C2-alkoxy or phenyl ; or R, is and R2 is C-C8-alkyl or phenyl that is unsubstituted or optionally substituted by one or two OR8 ; R3 and R7 independently of one another are methyl, methoxy, or chlorine; R5 is hydrogen or methyl ; R4 and R6 are hydrogen, R8 is Ci-C6-alkyl ; Most preferred is bis (2,4, 6-trimethylbenzoyl) phenylphosphine oxide.

Bisaxcylphosphine oxides are described in EP-B-184095 or US4737593.

Illustrative examples of photoinitiators described in US Patent 5,534, 559 and useful in the daylight curable compositions are: bis (2,4, 6-trimethylbenzoyl) methylphosphine oxide bis (2,4, 6-trimethylbenzoyl) ethylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-isopropylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-n-propylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-n-butylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-tert-butylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-(2-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-trimethylbenzoyl)-(1-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-trimethylbenzoyl)-cyclohexylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-n-pentylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-n-hexylphosphine oxide bis (2,4, 6-trimethylbenzoyl)- (2-ethyl-hex-1-yl) phosphine oxide bis (2,4, 6-trimethylbenzoyl)-n-octylphosphine oxide bis (2,4, 6-trimethylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl) phosphine oxide bis (2,4, 6-trimethylbenzoyl)-n-decylphosphine oxide bis (2,4, 6-trimethylbenzoyl)-phenylphosphine oxide (Irgacure 819) bis (2,4, 6-trimethylbenzoyl)- (4-methylphenyl) phosphine oxide bis (2, 6-dimethylbenzoyl)-methylphosphine oxide bis (2, 6-dimethylbenzoyl)-ethylphosphine oxide bis (2, 6-dimethylbenzoyl)-i-propylphosphine oxide bis (2, 6-dimethylbenzoyl)-n-propylphosphine oxide bis (2, 6-dimethylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl) phosphine oxide bis (2, 6-dimethylbenzoyl)- (2-methyl-prop-1-yl) phosphine oxide bis (2, 6-dimethylbenzoyl)-n-butylphosphine oxide bis (2, 6-dimethylbenzoyl)-t-butylphosphine oxide bis (2, 6-dimethylbenzoyl)- (l-methyl-prop-1-yl) phosphine oxide bis (2, 6-dimethylbenzoyl)-cyclohexylphosphine oxide bis (2, 6-dimethylbenzoyl)-n-pentylphosphine oxide bis (2, 6-dimethylbenzoyl)-n-hexylphosphine oxide bis (2, 6-dimethylbenzoyl)- (2-ethyl-hex-1-yl) phosphine oxide bis (2, 6-dimethylbenzoyl)-n-octylphosphine oxide bis (2, 6-dimethylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl) phosphine oxide bis (2, 6-dimethylbenzoyl)-phenylphosphine oxide bis (2, 6-dimethylbenzoyl)- (2, 5-dimethylphenyl) phosphine oxide bis (2, 6-dimethylbenzoyl)-n-octylphosphine oxide bis (2,4, 6-triethylbenzoyl)-methylphosphine oxide bis (2,4, 6-triethylbenzoyl)-ethylphosphine oxide bis (2,4, 6-triethylbenzoyl)-i-propylphosphine oxide bis (2,4, 6-triethylbenzoyl)-n-propylphosphine oxide bis (2,4, 6-triethylbenzoyl)-n-butylphosphine oxide bis (2,4, 6-triethylbenzoyl)-t-butylphosphine oxide bis (2,4, 6-triethylbenzoyl)- (2-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-triethylbenzoyl)- (1-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-triethylbenzoyl)-cyclohexylphosphine oxide bis (2,4, 6-triethylbenzoyl)-n-pentylphosphine oxide bis (2,4, 6-triethylbenzoyl)-n-hexylphosphine oxide bis (2,4, 6-triethylbenzoyl)- (2-ethyl-hex-1-yl) phosphine oxide bis (2,4, 6-triethylbenzoyl)-n-octylphosphine oxide bis (2,4, 6-triethylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl) phosphine oxide bis (2,4, 6-triethylbenzoyl)-n-decylphosphine oxide bis (2,4, 6-triethylbenzoyl)-phenylphosphine oxide bis (2, 6-diethylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl) phosphine oxide bis (2, 6-diethylbenzoyl)- (2-methyl-prop-1-yl) phosphine oxide bis (2, 6-diethylbenzoyl)-n-butylphosphine oxide bis (2, 6-diethylbenzoyl)-t-butylphosphine oxide bis (2, 6-diethylbenzoyl)- (1-methyl-prop-1-yl) phosphine oxide bis (2, 6-diethylbenzoyl)-cyclohexylphosphine oxide bis (2, 6-diethylbenzoyl)-n-pentylphosphine oxide bis (2, 6-diethylbenzoyl)-n-hexylphosphine oxide bis (2, 6-diethylbenzoyl)- (2-ethyl-hex-1-yl) phosphine oxide bis (2, 6-diethylbenzoyl)-n-octylphosphine oxide bis (2, 6-diethylbenzoyl)-phenylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)-n-butylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)-t-butylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)-(2-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-triisopropylbenzoyl)- (1-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-triisopropylbenzoyl)-cyclohexylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)-n-pentylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)-n-hexylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)- (2-ethyl-hex-1-yl)-phosphine oxide bis (2,4, 6-triisopropylbenzoyl)-n-octylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl)-phosphine oxide bis (2,4, 6-triisopropylbenzoyl)-n-decylphosphine oxide bis (2,4, 6-triisopropylbenzoyl)-phenylphosphine oxide bis (2,4, 6-tri-n-butylbenzoyl)- (2-methyl-prop-1-yl)-phosphine oxide bis (2,4, 6-tri-n-butylbenzoyl)- (2, 4, 4-trimethyl-pent-1-yl)-phosphine oxide bis (2,4, 6-tri-n-propylbenzoyl)- (2-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-tri-n-propylbenzoyl)-n-butylphosphine oxide bis (2,4, 6-tri- (1-methyl-prop-1-yl) benzoyl)-n-octylphosphine oxide bis (2,4, 6-tri- (1-methyl-prop-1-yl) benzoyl)-n-butylphosphine oxide bis (2,4, 6-tri-(2-methyl-prop-1-yl) benzoyl)-(2, 4, 4-trimethyl-pent-1-yl) phosp hine oxide bis (2,4, 6-tri- (2-methyl-prop-1-yl) benzoyl)- (2-methyl-prop-1-yl) phosphine oxide bis (2,4, 6-tri-t-butylbenzoyl)-n-butylphosphine oxide bis (2, 6-dimethyl-4-n-butyl-benzoyl)-(2-methyl-prop-1-yl) phosphine oxide bis (2, 6-dimethyl-4-n-butyl-benzoyl)-phenylphosphine oxide bis (2,4, 6-trimethyl-benzoyl)-(2, 5-dimethylphenyl) phosphine oxide bis (2, 6-dimethyl-4-n-butyl-benzoyl)-(2,5-dimethylphenyl) phosphine oxide, bis (2, 6-dimethoxybenzoyl)- (2, 4, 4-trimethylpent-1-yl) phoshine oxide and bis (2, 6-dichlorobenzoyl)- (4-propylphenyl) phoshine oxide.

Especially preferred photoinitiators are: Monoacylphosphine oxides such as, for example, Lucirin TPO (commercially available from BASF) or [Benzyl- (4-morpholin-4-yl-phenyl)-phosphinoyl]- (2, 4, 6-trimethyl-phenyl)-methanone which can be prepared according to the PCT Application PCT-EP02/09045 filed August 13, 2002, [(2-Ethyl-heXyl)-(2, 4, 4-trimethyl-pentyl)-phosphinoyl]-(2, 4, 6-trimethyl-phenyl)-methanone which can be prepared according to the German Patent Publication 10127171 or the British patent GB2365430;, 2,4, 6-trimethylbenzoyl-phenyl phosphinic acid ethyl ester (BASF).

Bisacvlphoshine oxides such as, for example, Irgacure 819, commercially available from Ciba.

Acylphosphine sulfides such as, for example, [phenyl-(2, 4, 6-trimethyl-benzoyl)-phosphinothioyl]- (2, 4, 6-trimethyl-phenyl)-methanone which can be prepared according to US 5,368, 985, or 9- (2, 4, 6-trimethylbenzoyl)-9-phosphabicyclo [3.3. 1] nonane-9-sulfide, which can be prepared according to US 5,399, 782. Phenylglyoxalates such as, for example Nuvopol 3000 commercially available from Stauffer. Phenylglyoxalate diester of diols such as Oxo-phenyl-acetic acid 2- [2- (2-oxo-2-phenyl- acetoxy)-ethoxy]-ethyl ester which can be prepared according to US6, 048, 660.

The Photoinitiator may be present in an amount from about 0, 3-1 Owt%, preferably from about 0, 3-5wt%, more preferably from about 1-2wt%.

Diluent The residues in the above formula la-le are defined as follows : C1-C12Alkyl is linear or branched and is for example C1-C12-, C1-C8-, C-C6-or C1-C4alkyl.

Examples are methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, pentyl, hexyl, heptyl, 2,4, 4-trimethyl-pentyl, 2-ethylhexyl, octyl, nonyl, decyl, undecyl or dodecyl.

The substituted C1-C12alkyl residue may be substituted once or more than once. It is also possible that the substituents are not the same. An example may be a residue like A residue of an acrylic acid is-CH=CHCOOH.

Ci-C6alkoxycarbonyl is for example-C (O) OCH3, -C (O) OCH2CH3.

Ci-C6alkylaminocarbonyl is for example-C (O) NHCH3.

Ci-C6alkylcarbonyloxy is for example-O-C (O) CH3.

Ct-C6alkenylcarbonyloxy is for example-O-C (O) CH=CH2.

(Meth) acryloyloxy refers to acryloyloxy (CH2=CH-COO-) or methacryloyloxy (CH2=C (CH3)-COO-).

Phenyl substituted once or more than once by C1-C12alkyl is for example-C6H4CH3, -C6H3(CH3)2, -C6H2(CH3)3, -C6H(CH3)4, -C6(CH3)5, -C6H4(CH2)7CH3, -C6H4(CH2)11CH3, - C6H4-C6H11; -C6H4CH (CH3) 2,-C6H4C (CH3) 3.

Phenyl substituted once or more than once by halogen is for example-C6H4F,-C6H4CI, -C6H4Br,-C6H41,-C6H3F2,-C6H3C12,-C6H4Br,-C6H4CF3,-C6H3 (CF3) 2.

Phenyl substituted by Ci-Ceaikoxycarbonyioxy is for example phenyl substituted by tert. butoxycarbonyloxy (-C6H40C (O) OC (CH) 3).

Phenyl substituted by C1-C6alkylcarbonyloxy is for example phenyl acetate.

Acetylsulfanyl refers to CH3-COS-.

C1-C12alkoxy substituted more than once by fluor is for example-OCH (CF3) 2,-O (CF2) 7CF3.

Benzyl substituted by a residue selected from an amino butyric acid is for example -C6H4CH2NH (CH2) 3COOH-.

Benzyl substituted by Ci-C6alkylsulfonyl or Ct-C6alkylsulfonium salts, for example -C6H4CH2SO2 (CH2) 2CI, or C6H4CH2S+ (CH2CH3) 2CI-.

Benzyl substituted by a silanol residue is for example-C6H4CH2CH (Si (OCH2CH3) 3) ) CH3, -C6H4CH2OSi (CH3) 3 or-C6H4CH2OSi (CH3) 2C (CH3) 3.

Benzyl substituted by a residue of a phosphonic acid is for example -C6H4CH2P (O) (OCH2CH3) 2.

When Y is O-C1-C12alkylene, wherein the alkylene linker is linear or branched and may be interrupted once or more than once by oxygen, the following linkers may be listed as examples :-O (CH2) 3-,-O (CH2) 30C (CH2) 3-,-OCH2C (CH20CH2CH=CH2) (CH2CH3) CH2-, The group -(CR6R7)m- also includes structures like-CH2CH2CH (CH3) CH2CH2-.

A phthalate residue is for example A maleate residue is for example C-C6Alkoxy is likewise linear or branched and is, for example, methoxy, ethoxy, propoxy, isopropoxy, n-butyloxy, sec-butyloxy, iso-butyloxy, tert-butyloxy, pentoxy or hexoxy.

Aryl is for example phenyl, 1-naphthyl, 2-naphthyl, anthracenyl, phenanthryl, in particular phenyl. The aryl residues can be mono-or polysubstituted.

Concerning the residue R3, the phenyl ring is preferably para substituted Concerning the residue R4, the phenyl ring is preferably unsubstituted or para substituted.

The residue of formula I b is Examples for the residue Rl-Rs are as follows : R,-H, - CH3,-CH2CH3,-CH2CH2CH2CH3,- (CH2) 5CH3, -(CH2)9CH3, -CH=CHCOOH, -CH2OH, -CH (OH) CH3,-C (CH3) (OH) C#CH, -CH2O-C(O0CH=CH2, -CH2O-C(O0C(CH3)=CH2, -CH2OC(O)NHC6H4CH3, -CH2NHCH2CH2CH3, -CH2Cl, -C(O0OCH3, -C(O) OCH2CH3, -C(O) NHCH3, <BR> <BR> <BR> <BR> -CHO,<BR> <BR> <BR> <BR> <BR> -C (O) C6H5, - CN -OH, -OC(O)CH3, -O-C(O)CH=CH2, -O-C(O) C (CH3) =CH2, -Cl R2-H,-CH3,-CH2CH3,-CH2CH2CH2CH3,- (CH2) 5CH3,- (CH2) 9CH3, -CH2OH, -CN, -OH, -OC(O0CH3, -Cl R3 -1-C10H7, -2-C10H7,- C14H9, -C6H4C6H5,-C6H4CH=CH2,-C6H4CH20H, -C6H4CH3, -C6H3(CH3)2, -C6H2(CH3)3, -C6H1(CH3)4, -C6(CH3)5, -C6H4 C6H4(CH2)7CH3, -C6H4(CH2)11CH3, -C6H4CH9CH2)5, -C6H4CH(CH3)2, -C6H4(CH3) 3 -C6H4F, -C6H4Cl, -C6H4Br, -C6H4I, -C6F4, -C6H3F2, -C6H3Cl2, -C6H4Br, -C6H4CF3, -C6H3(CF3)2, - C6H4CH2CI,-C6H4CH2S02 (CH2) 2CI,-C6H4CH2CN, -C6H4CH2CH (Si (OCH2CH3) 3) ) CH3, - C6H4CH20Si (CH3) 3,-C6H4CH20Si (CH3) 2C (CH3) 3, -C6H47CH2OC(O)CH3, -C6H4CH2O-C(O)CHCH2, -C6H4CH2O-C(O0C9CH3)CH2, -C6H4CH2OCH2CH(O)CH -C6H4CH2OC(O0CF3, -C6H4CH2OCH (CF3) 2,-C6H4CH20 (CF2) 7CF3, -C6H4CH2N (CH3) 2, -C6H4CH2N (CH3) 3+Cl-, -C6H4CH2NH (CH2) 3COOH, -C6H4CH2P(O0(OCH2CH3) 2 -C6H4CH2SC (O) CH3,-C6H4CH2S+ (CH2CH3) 2Cl-, -C6H4CH2SO3-Na+ -C6H4CN, -C6H4OH, -C6H4O-C(O)CH=CH2, -C6H4O-C(O) C (CH3) =CH2, -C6H4OC(O)CH3, -C6H4OC(O) OC (CH) 3, -C6H4OCH3, -C6H4OCH2CH3, -C6H4OC(CH3)3, -C6H4OC6H5, -C6H3(OCH3)OH, -C6H3(OCH3)2, -C6H3(OCH3)(OCH2C6H5), -CH2-O-CO-CH=CH2 or -CH2-O-CO-C(CH3)=CH2 R4 -H, -CH2OH -CH20C (O) H CH20C (O) C6H5, -CH2OCH3, -CH2OCH2CH3, -CH2OCH2CH2CH3, -CH2OCH2CH2CH3, ,-CH20CH2CH2CH2CH3,-CH20C6H5 -CH20-C (O) CH=CHC (O) OCH2CH=CH2, -CH2O-C(O)C6H4C(O) OCH2CH=CH2, -CH2O-C(O)CH=CH2, -CH2O-C(O) C (CH3) =CH2, -CH2O (CH2) 30-C (O) CH=CH2, -CH2O (CH2) 30-C (O) C (CH3) =CH2, -CH2O (CH2) 30C (CH2) 30-C (O) CH=CH2, -CH20 (CH2) 30C (CH2) 30-C (O) C (CH3) =CH2, -CH2OCH2C (CH20CH2CH=CH2) (CH2CH3) CH20-C (O) C (CH3) =CH2, -CH2CH2O-C(O) CH=CH2, -CH2CH2O-C(O) C (CH3) =CH2, - CH2CH2CH (CH3) CH2CH20-C (O) C (CH3) =CH2, -CH2CH2CH (CH3) CH2CH20-C (O) C (CH2CH3) =CH2, ~C6H5-l-C10H-2-C1oH7s-C14Hg, -C6H4C6H5, -C6H4CH=CH2, - C6H4CH3, -C6H3(CH3)2, -C6H2(CH3)3, -C6H1(CH3)4, -C6(CH3)5, -C6H4(CH2)7CH3, -C6H4(CH2)11CH3, -C6H4CH (CH2) 5, -C6H4CH (CH3) 2,-C6H4C (CH3) 3 -C6H4F, -C6H4Cl, -C6H4Br, -C6H4I, -C6F4, -C6H3F2, -C6H3Cl2, -C6H4Br, - C6H4CF3, -C6H3(CF3)2, -C6H5, -1-C10H7, -2-C10H7,- C14H9, -C6H4C6H5, -C6H4CH=CH2, -C6H4CH3, -C6H3(CH3)2, -C6H2(CH3)3, -C6H1(CH3)4, -C6(CH3)5, -C6H4(CH207CH3, -C6H4(CH2)11CH3, -C6H4CH(CH2)5, -C6H4CH(CH3)2, -C6H4C(CH303 -C6H4F, -C6H4Cl, -C6H4Br, -C6H4I, -C6F4, -C6H3F2, -C6H3Cl2, -C6H4Br, <BR> <BR> <BR> <BR> -C6H4CF3,-C6H3 (CF3) 2,<BR> <BR> <BR> <BR> <BR> <BR> <BR> - C6H4CH2C1,-C6H4CH2S02 (CH2) 2CI,-C6H4CH2CN, -C6H4CH2CH(Si (OCH2CH3) 3) ) CH3, -C6H4CH2OH, -C6H4CH2OSi(CH303, -C6H4CH2OSi(CH3)2C (CH3) 3, -C6H4CH2OC(O) CH3, -C6H4CH20-C (O) CHCH2, -C6H4CH2O-C(O) C (CH3) CH2, -C6H4CH2OCH2CH(O0 CH -C6H4CH20C (O) CF3,-C6H4CH20CH (CF3) 2,-C6H4CH20 (CF2) 7CF3, -C6H4CH2N (CH3) 2,-C6H4CH2N (CH3) 3+CI-,-C6H4CH2NH (CH2) 3COOH, -C6H4CH2P(O) (OCH2CH3) 2 <BR> <BR> <BR> -C6H4CH2SC (O) CH3,-C6H4CH2S+ (CH2CH3) 2CI-,-C6H4CH2SO3~Na+<BR> <BR> <BR> <BR> <BR> -C6H4CN, -C6H4OH, -C6H4O-C(O) CH=CH2, -C6H40-C (O) C (CH3) =CH2, -C6H4OC(O0CH3, -C6H4OC(O) OC (CH) 3, - (CH3) 3,-C6H40C6H5, -C6H3(OCH3)OH, -C6H3(OCH3)2, -C6H3(OCH30(OCH2C6H5), R5-H,-CH3.

Preferably the compounds of the formula la-le are those wherein R1 and R2 are hydrogen; R3 is (meth) acryloyloxy-methyl or phenyl para substituted by vinyl, R4 is phenyl or phenyl para substituted by vinyl or (meth) acryloyloxy ; or a substituted phenyl residue of the formula-C6H4CH2-W, wherein W is (meth) acryloyloxy, or an aliphatic residue of the formula-CH2-Y-A, wherein Y is a bond, O-C1-C12alkylene, wherein the alkylen linker is linear or branched and may be interrupted once or more than once by oxygen, A is hydroxy, C1-C6alkoxy, acetoxy, (meth) acryloyloxy, or a phthalate- or maleate-residue ; R5 is hydrogen n is 1 ; x is- (CH2)-.

More preferably the compounds of the formula la-le are those wherein Ri and R2 are hydrogen R3 is (meth) acryloyloxy-methyl or phenyl para substituted by vinyl, R4 is phenyl or phenyl para substituted by vinyl ; or an aliphatic residue of the formula-CH20H,-CH2- (meth) acryloyloxy, - CH2-acetoxy or-CH2-O-Ci-Cl2alkyl or-CH2-A, wherein A is a phthalate-or maleate-residue ; R5 is hydrogen n is 1 ; x is-(CH2)-.

The diluent may be present in an amount of 5 to 50wt%, preferably 10 to 30wt%.

Especially preferred compounds of the formula la are Especially preferred compounds of the formula lb are the following molecules including their E/Z isomers and regioisomers.

Especially preferred compounds of the formula Id are: Especially preferred compounds of the formula le are: Preferred embodiment A coating composition comprising (1) an alkyd resins, (2) a reactive diluent of the formula la-le as defined above or mixtures thereof, (3) 0.3 to 10 wt. % of a mono-, bis-or trisacylphosphinoxide photoinitiator of the formula X is 0 or S ; Ri and R2 independently of one another are linear or branched C1-C12-alkyl, C1-C12-aloxy, phenyl, unsubstituted or optionally substituted by OR8, SR9, NR1oR11, Ci-C12-Alkyl or halogen ; or Ri and R2 are phenyl-C1-C4-alkyl or R3 and R7 independently of one another are Ct-Ct2-alkyl, C-Ct2-alkoxy or halogen ; R4, R5 and R6 independently of one another are hydrogen, C1-C12-alkyl, C1-C12-alkoxy or halogen ; R8, Rg Rio and Rtt independently of one another are hydrogen, Cl-C, 2-alkyl, C2-Cl2-alkenyl, benzyl or C2-C2o-alkyl interrupted once or several times by -O-; or Rio and Rtt represent together with the N-atom that they are attached to an optionally oxygen-or-NR12-containing 5 or 6 membered ring; Ris is hydrogen, phenyl-C-C4-alkyl or Ct-C 2-alkyl.

It is also possible to use mixtures with other known reactive diluents.

Especially suitable is Irgacure 819 (bis (2,4, 6-trimethylbenzoyl)-phenylphosphine oxide) Additives The coating composition according to the invention may furthermore contain various additives such as UV stabilizers, cosolvents, dispersants, surfactants, inhibitors, fillers, anti- static agents, flame-retardant agents, lubricants, antifoaming agents, extenders, plasticizers, anti-oxidants, anti-freezing agents, waxes, thickeners, thixotropic agents, etc. The composition may be used as a clear varnish or may contain pigments. Examples of pigments suitable for use are metal oxides, such as titanium dioxide or iron oxide, or other inorganic or organic pigments.

The coating composition according to the present invention can be applied by conventional methods, including brushing, roll coating, spray coating, or dipping.

Preparation The compounds of formula la-le can be prepared starting from the following cycloolefins la'- le' The above cyclo-olefins are reacted in the presence of a metathesis catalyst with a terminal olefin of the formula X, Ri, R2, R4, R5 are as defined above.

The cyclo-olefins can be prepared by Diels-Alder reactions analogue to the case described for example in W097/32913.

The following cyclo-olefins are commercially available.

Suitable metathesis catalyst are ruthenium, molybdenum or osmium metal carbene complex as for example described in EP0885911A1, EP0839821A2, EP0808338B1, W093/20111, W095/07310, W096/16101, W097/14738A1, W097/31913, W097/38036A1, W097/32913, W098/39346A1, W099/29701A1, W099/00397A1 and W099/00396A1.

Preferred are ruthenium carbenes of the formula (X) with two phosphine ligands and two halogen atoms such as disclosed in W097/32913. wherein T, and T2 independently of one another are tertiary phosphines, or T1 and T2 together are a tertiary diphosphine; T3 is H, C1-C12alkyl, C3-C6cycloalkyl, C3-C7heterocycloalkyl with one or two heteroatoms selected from the group consisting of -O-, -S- and -N-; C6-C14 aryl, or C4-CI5 heteroaryl with one to three heteroatoms selected from the group consisting of-O-,-S-and-N-which are unsubsituted or substituted by Ci-Ci2 alkyl, C1-C12haloalkyl, C1-C12 alkoxy, C6-C10aryl, C6- Cioaryloxy, NO2 or halogen ; Xoi and X02 independently of one another are halogen.

Some specific examples are: Cl2[P(C6H11)3]2Me=CH-C6H5, Cl2[P(C5H9)3]2Me=CH-C6H5, Br2 [P (C6H11)3]2Me=CH-C6H5, Br2 [P (C5H9) 3]2Me=CH-C6H5, F2[P(C6H11)3]2Me=CH-C6H5, F2[P(C5H903]2Me=CH-C6H5, Cl2 [P (C6H11)3]2Me=CH(C6H4-Cl), Cl2[P(C5H9)3]2Me=CH(C6H4-Br), Br2 [P (C6H11)3]2Me=CH(C6H4-NO2), Br2 [P (C5H9) 3]2Me=CH(C6H4-OC2H5), Cl2 [P (C8H11)3]2Me=CH (C6H4-CH3), F2 [P (C5H9) 3]2Me=CH[C6H3-(CH3)2], Cl2 [P (C6H11) 3]2Me=CH-C10H9, Cl2[P(C5H9)3]2Me=CH-CH3, Cl2[P(C6H11)3]2Me =CHCH3, Br2 [P (C5H9)3]2Me=CH-i-C3H7, Cl2 [P (C6H11)3]2Me=CH-t-C4H9, Cl2 [P (C5H9) 312Me=CH- n-C4H9, Cl2 [P (C6H11) 3] 2Me=CH-C6H4-OCH3, Cl2 [P (C5H9) 3]2Me=CH-C6H3-(CH3)2, Br2 [P (C6H11) 3] 2Me=CH-C6H2-(CH3) 3, Br2 [P (C5H9) 3] 2Me=CH-CH2C6H5, Cl2 [P (t-C4H9) 3] 2Me=CH-C6H5, Ci2 [P (i-C3H7) 3]2Me=CH-C6H5, Cl2 [P (C8H5) 3] 2Me=CH-C6H5, Cl2 [P (C6H3-CH3) 3]2Me=CH-C6H5, Br2 [P (C5H4- (CH3) 2) 3] 2Me=CH-C6H5, Cl2 [(C6H3-(CH3)3]2Me=CH-C6H5, Cl2 [P (C6H11)3-CH2CH2-P(C6H11)3]Me=CH-C6H5, Cl2 [P (C5H9) 3]2Me=CH-C6H11, Cl2[P(C5H9)3]2Me=CH-C5H9, Cl2 [P (C5H9) 3] 2Me=C (C6Hn) 2, Cl2 [P (C6H11)3]2Me=CH2, Cl2 [P (C5H9) 3]2Me=CH2, Cl2 [P (C6H11)3]2Me=CH-NBUTYL, Cl2 [P (C3H7) 3]2Me=CH-C6H5, Cl2 [P (C3H7) 3]2Me=CH-C6H11, Cl2[P(i-C3H7)3]2Me=CH-C6H5, Cl2[P(i-C3H7)3]2Me=CH-C5H11 Also preferred are catalysts as described in W099/29701 such as, for example, The choice of the catalyst is not critical.

Especially preferred is bis- (tricyclohexylphosphin) benzyliden ruthenium- (IV)-dichloride Cl2 [P (C6Ht t) 3] 2Me=CH-C6H5.

Also preferred is Cl2 [P (C3H7) 3] 2Me=CHS-C6H5.

The metathesis catalyst is used in an amount of 0.005wt% up to 5wt%, preferably 0.05 to 0. 2wt%. The Ru-catalyst is removed by absorption on a polar support. After distillation of the volatile reaction by-products, the product of formula I is obtained without any further purification.

Advantageous The inventive diluents of the formula la-le can be prepared in one step using ring opening metathesis polymerization. Thus, multifunctional products can be obtained, having a high double bond density, depending on the choice of the reaction parameters.

When using the inventive diluents, it is possible to replace the siccatives by photoinitiators.

The inventive coating compositions are storage stable under exclusion of light.

Polymerisation occurs only when the compositions are exposed to light. The inventive coating compositions are tack-free after standard radiation curing.

Use The inventive compositions are especially suitable for use as a decorative or do-it-yourself coating, e. g. for wood substrates, such as door-or window frames, but can also be used in industry, in particular for wooden substrates. The coating composition may also be used for substrates made of metal, concrete, plastic materials or other materials.

Furthermore the coatings may be used in sheetfed offset printing inks. These inks preferably contain resin mixtures including alkyd resins. Suitable resin mixtures are: Terlon 3, Sparkl 609, Luminex 11.

Experimentals Example 1 2-Methy !-acrVlic acid 3- (3-vinvl-1. 2. 3. 3a, 4. 6a-hexahvdro-pentalen-1-yl)-alivi ester Compound of formula lb with R4 = CH2-Y-A, Y=bond, A is methacryloyloxy.

A three-neck flask equipped with magnetic stirrer, thermometer and a reflux condenser and equipped for nitrogen flow is flushed with nitrogen. The flask is charged with (19. 8g, 0.15 mol) dicyclopentadiene and with (113.5 g, 0.90 mol) allylmethacrylate. The solution is stirred under nitrogen at room temperature followed by the addition of a solution of 0.5 mol% of bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride dissolved in 1. 5mi dichloromethane.

After the exothermic reaction is over, the flask is allowed to cool until reaching room temperature and stirring is carried out for a further 2 hours at room temperature. The progress of the reaction is controlled by gas-chromatography (GC). 200 ml hexane and 15 g bleaching earth (Tonsil AC) are added to the reaction mixture. Stirring is carried out for a further 15 minutes and the solid is filtered off. After evaporation of hexane and surplus allylmethacrylate under vacuum, a colorless oil is obtained (37.7 g, 90% of theory) which, after characterization by'H-NMR, proves to be the desired compound as major compound.

In order to stabilize the oil 1000ppm HQM (hydroquinone monomethylether) is added.

Example 2 Acetic acid 3-(3-vinyl-1, 2, 3, 3a, 4, 6a-hexahYdro-pentalen-1-yl)-allyl ester Compound of formula lb with R4 = CH2-Y-A, Y=bond, A is acetoxy.

Acetic acid 3- (3-vinyl-1, 2,3, 3a, 4, 6a-hexahydro-pentalen-1-yl)-allyl ester is prepared according to Example 1 using 6.6 g, 0.05 mol dicyclopentadiene and 30.0 g, 0.30 mol allylacetate in the presence of 0.3 mol% bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride. 11.0 g of a low-viscous oil is obtained (99% of theory) which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

Example 3 3-(3-Vinyl-1,2,3,3a,4,6a-hexahydro-pentalen-1-yl)-prop-2-en- 1-ol Compound of formula lb with R4 = CH2-Y-A, Y=bond, A is hydroxy 3- (3-Vinyl-1, 2,3, 3a, 4, 6a-hexahydro-pentalen-1-yl)-prop-2-en-1-ol is prepared according to Example 1 using 6.75 g, 0.051 mol dicyclopentadiene and 17.79 g, 0.30 mol allylalcohol in the presence of 0.3 mol% bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride.

6.34 g of an oil is obtained. After distillation under high vacuum in a ball-tube oven 5.15g (53%) of a colorless oil is obtained which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

Example 4 1- (3-Butoxv-propenyl)-3-vinvl-1, 2. 3, 3a, 4, 6a-hexahvdro-pentalene Compound of formula lb with R4 = CH2-Y-A, Y is a bond, A is alkoxy 1- (3-Butoxy-propenyl)-3-vinyl-1, 2,3, 3a, 4, 6a-hexahydro-pentalene is prepared according to Example 1 using 10.7 g, 0.081 mol dicyclopentadiene and 9.2 g, 0.81 mol allylbutylether in the presence of 0.1 mol% bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride. 9.8 g of a colorless oil is obtained (49% of theory) which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

Example 5 But-2-enedioic acid allyl ester 3-(3-vinyl-1,2,3,3a,4,6a-hexahydro-pentalen-1-yl)-allyl ester Compound of formula Ib with R4 = CH2-Y-A, Y is a bond, A is a maleate residue. But-2-enedioic acid allyl ester 3- (3-vinyl-1, 2,3, 3a, 4, 6a-hexahydro-pentalen-1-yl)-allyl ester is prepared according to Example 1 using 13.2 g, 0.10 mol dicyclopentadiene and 19.6 g, 0.10 mol diallylmaleaet in the presence of 0.1 mol% bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride. 27.8 g (85% of theory) of a light brown oil is obtained which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

Example 6 Phthalic acid 1-allyl ester 2-[3-(3-vinyl-1,2,3a,4,6a-hexahydro-pentalen-1-yl)-allyl] ester Compound of formula lb with R4 = CH2-Y-A, Y is a bond, A is a phthalate residue Phthalic acid 1-allyl ester 2- [3- (3-vinyl-1, 2,3, 3a, 4, 6a-hexahydro-pentalen-1-yl)-allyl] ester is prepared according to Example 1 using 13.2 g, 0.10 mol dicyclopentadiene and 24.6 g, 0. 10 mol diallylphthalate in the presence of 0.1 mol% bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride. 35.8 g (95% of theory) of a light brown oil is obtained which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

Example 7 1-Styrvl-3-vinvl-1, 2, 3, 3a, 4, 6a-hexahvdro-pentalene Compound of formula lb with R4 = phenyl. 1-Styryl-3-vinyl-1, 2,3, 3a, 4, 6a-hexahydro-pentalene is prepared according to Example 1 using 5.6 g, 0.042 mol dicyclopentadiene and 13.2 g, 0.12 mol styrene in the presence of 0.3 mol% bis- (tricyclohexylphosphin) benzylidene ruthenium- (IV)-dichloride. 7.9 g (79% of theory) of a colorless oil is obtained which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

Example 8 3-Vinyl-1-[2-(4-vinyl-phenyl)-vinyl]-1,2,3,3a,4,6a-hexahydro - pentalene Compound of formula lb with R4 is phenyl para substituted by vinyl.

3-Vinyl-1- [2- (4-vinyl-phenyl)-vinyl]-1, 2,3, 3a, 4, 6a-hexahydro- pentalene is prepared according to Example 1 using 6.6 g, 0.05 mol dicyclopentadiene and 19.5 g, 0.15 mol divinylbenzene in the presence of 0.05 mol% bis-(tricyclohexylphosphin) benzylidene ruthenium-(lV)-dichloride.

11.7 g (89% of theory) of a colorless oil is obtained which, after characterization by 1 H-NMR, contains the reactive diluent as major compound.

1000ppm Irganox 1520 are added for stabilisation.

Example 9 1-Vinyl-4- [2- (3-vinyl-cyclopentyl)-vinyl]-benzene Compound of the formula la with R3 = phenyl para sunstituted by vinyl. 1-Vinyl-4- [2- (3-vinyl-cyclopentyl)-vinyl]-benzene is prepared according to Example 8 using norbornene and divinylbenzene.

Products with n= 2 are for example: Application Examples 1. Coating compositions: Formulation I Comparative A Ingredients % % Jagol PS 21 (Ernst Jager) alkyd resin 73. 80 73. 80 Exsol D 40 (aliphatic hydrocarbon), solvent 21. 19 Exkin 2 (methylethylketoxim), anti skinning 0. 52 Octa-Soligen Calcium 10 (Borchers GmbH) drier 0. 25 Octa-Soligen Zirkonium 6 (Borchers GmbH) 2. 33 Octa-Soligen Cobalt 6 (Borchers GmbH) 0. 62- Octa-Soligen Zink 6 (Borchers GmbH) 0. 57 Lanco Glidd AH (Lubrizol Coating Additives) 0. 72 0. 72 IRGACURE 819 photoinitiator-2. 0 reactive diluent - 21. 19 1100. 0100. 0 IRGACURE 819: Bis (2,4, 6-trimethylbenzoyl)-phenylphosphineoxide Formulation II comparative A Ingredients % % Worléekyd B870,75% (Worlée Chemie); alkyd 80.0 80.0 Varsol D30 (aliphatic hydrocarbon) solvent 17.5 - Exkin 2 (methylethylketoxim) 0.5 - Octa-Soligen Calcium 10 (Borchers GmbH) 1.0 - Octa-Soligen Zirkonium 6 (Borchers GmbH) 0.6 - Octa-Soligen Cobalt 6 (Borchers GmbH) 0.4 - Irgacure 819 - 2.0 Reactive diluent - 17.5 # 100.0 100.0 For evaluation of the drying behavior the above coatings are applied with a 76 um slit coater to glass and the measurement with the BK-Recorder is started under different light sources at once. A needle is put on the wet film and is pushed with a constant speed of 28 cm/6h through the film. The record shows five different phases of the drying process within the first 6 hours after application. For evaluation the end of the phases 1 to 4 are listed. Phase 1 No remaining line (wet film) Phase 2 Smooth remaining line (increased viscosity of the coating) Phase 3 Fringed line (gelation) Phase 4 Interrupted line or surface marks (crosslinking) Phase 5 No visible marks Picture 1: Different phases of the BK-Recorder measurement. I t"W I Phase 1 t t Phase 3/Phase 5 Phase 4 Phase 2 Phase 4 The pendulum hardness is determined at 100 um on glass plates.

As light sources two fluorescent lamps TL 20W/03 (Philips; distance: 27 cm), common fluorescent daylight lamps (Hanau 001660 40W) and diffuse indoor daylight are used.

The viscosity of the formulations is determined by ICI plate-plate viscometer after preparation and different storage time.

Drying behaviour Tables 1 and 2 show the drying behavior of the above alkyd systems upon exposure to fluorescent and daylight lamps. The values are given in min.

Tab. 1 Formulation I TL03/20W-lamp Daylight lamp phase phase 1 2 3 4 1 2 3 4 Comparative 48 58 77 113 68 85 98 184 A: diluent Ex. 1 4 8 31 60 19 28 144 180 Tab. 2 Formulation II TL03/20W-lamp Daylight lamp phase phase 1 2 3 4 1 2 3 4 Comparative 81 109 150 216 45 141 183 226 A: diluent 17 31 67 202 32 49 77 159 accord. to Ex. 8 A: diluent 6 10 57 90 19 31 81 231 accord. to Ex. 1 Pendulum hardness Tab. 3 shows the pendulum hardness upon fluorescent lamps and indoor daylight exposure in the Formulation II.

The use of the reactive diluents and photoinitiator IRGACURE 819 causes a significant increase of the pendulum hardness after one week. The storage stability is good.

Table. 3 pendulum hardness (s) after 168 hours TL03/20W-lamp Daylight Comparative Formulation II 33 21 A: diluent accord. to Ex. 8 75 57 A: diluent accord. to Ex. 1 84 50 Comparison of the reactive diluents in Formulation II The formulation containing a diluent according to the invention shows a slightly improved drying behavior. Diallylfumarate, Diethylfumarate and Diallylmaleate do not lead to an increase of the pendulum hardness compared to formulation containing a diluent according to the invention.

Table 4: drying behavior of formulation II upon daylight lamps. values given in min. phase 1 phase 2 phase 3 phase 4 Comparative 42 160 188 254 Example 1 32 54 98 158 Diethylfumarate 36 56 77 102 Diallylmaleate 58 68 84 110 Diallylfumarate 60 74 89 113 Table 5 pendulum hardness after exposure to indoor daylight and initial viscosity in Formulation II Pendulum hardness (s) Viscosity (P) Exposure time (h) 330 500 0 Comparative 23 25 5. 1 Example 1 70 84 7. 8 Diethylfumarate 17 18 4. 4 Diallylmaleate 15 15 4. 2 Diallylfumarate 14 15 4. 4 Alternative embodiment Using mono-or bisacylphosphinoxides as photoinitiators, it has been found that the alkyd coating composition can be cured without any reactive diluent.

Thus, the invention further relates to a coating composition based on an alkyd resin comprising Mapo/Bapo photoinitiators.

In the US-Publication 20020026049 it is stated that Mapo photoinitiators may be suitable as initiators for the curing of oxidatively drying systems without specifying the system. There is no hint to solvent based or water based alkyd coating systems.

It has been found that the siccative and the antiskinning agent can be replaced by using mono-bis-or trisacylphosphinoxides as photoinitiators, thus obtaining a metal free, especially cobalt free and methyl ethyl ketoxime (MEKO) free coating composition.

Cobalt dust and MEKO are both considered to be cancer suspect agents.

Thus, the invention relates to a solvent based or water based alkyd coating composition comprising 0.3 to 10 wt. % of a mono-, bis-or trisacylphosphinoxide photoinitiator of the formula I I as describes above.

Preferred are compounds of the formula I'as describesd above.

Especially preferred are compounds of the formula I'as described above.

Most preferred is bis (2,4, 6-trimethylbenzoyl) phenylphosphine oxide.

The invention further relates to the use of a mono-, bis-or trisacylphosphinoxide photoinitiator to cure siccative free and/or anti-skinning agent free alkyd resins.

The invention further relates to a process for curing a solvent based or water based alkyd resin by photochemical treatment with light of a wavelength from 200 to 600 nm.

Definitions and preferences Alkvd resin Alkyd resins are those as described above.

Solvent Solvents are aliphatic, cycloaliphatic and aromatic hydrocarbons such as mineral spirits known as white spirit, as well as xylene, toluene, alcohol ethers, glycol ethers, ketones, esters, alcohol ether acetates or mixtures thereof.

As non limiting examples of such solvents may be mentioned toluene, xylene, hydrocarbon solvents available under the trademarks Exsol and Varsol from Exxon Chemicals Co. , and solvents such as ethyl acetate, butylacetate, ethyl diglycol, ethyl glycol acetate, butyl glycol, butyl glycol acetate, butyl diglycol, butyl diglycol acetate, and methoxypropylene glycol acetate. Mixtures of solvents may also be used.

Photoinitiators : Suitable bisacylphosphine oxides and their preparation by oxidation of the corresponding bisacylphosphines are described in EP-B184095 or US4737593.

Preferred bisacylphosphinoxides are those described in US Patent 5,534, 559. and listed above.

Especially preferred photoinitiators are: Monoacvlphosphine oxides such as, for example, Lucirin TPO (commercially available from BASF) or [Benzyl- (4-morpholin-4-yl-phenyl)-phosphinoyl]- (2, 4, 6-trimethyl-phenyl)-methanone which can be prepared according to the PCT Application PCT-EP02/09045 filed August 13, 2002, or [(2-Ethyl-hexyl)-(2, 4, 4-trimethyl-pentyl)-phosphinoyl]-(2, 4, 6-trimethyl-phenyl)-methanone which can be prepared according to US-Publication 20020026049 corresponding to the British patent publication GB2365430;, or 2,4, 6-trimethylbenzoyl-phenyl phosphinic acid ethyl ester (BASF).

Bisacvlphoshine oxides such as, for example, Irgacure 819, commercially available from Ciba. It is also possible to use Acylphosphine sulfides such as, for example, [phenyl- (2, 4, 6-trimethyl-benzoyl)-phosphinothioyl]- (2, 4, 6-trimethyl-phenyl)-methanone which can be prepared according to US 5,368, 985, or 9- (2, 4, 6-trimethylbenzoyl)-9-phosphabicyclo [3.3. 1] nonane-9-sulfide, which can be prepared according to US 5, 399, 782.

Especially preferred are bisacylphosphine oxides, for example Irgacure 819 or its dispersion in water (Irgacure 819DW). Typical amounts of the photoinitiator can be, for example, about 0.3 wt. % to about 10 wt. %, and preferably, about 1 wt. % to about 5 wt. %.

Additives The coating composition according to the invention may furthermore contain various additives as described above.

Coating compositions according to the invention can be used for coating precoated or uncoated substrates of wood, metal, plastics, ceramics, concrete, etc.

The coating composition according to the present invention can be applied by conventional methods, including brushing, roll coating, spray coating, or dipping.

Application Examples 1. Coating compositions: Formulation I Comparative B Ingredients % % Jagol PS 21 (Ernst Jager) alkyd resin 73. 80 73. 80 Exsol D 40 (aliphatic hydrocarbon), solvent 21. 19 21.19 Exkin 2 (methylethylketoxim), anti skinning 0. 52 Octa-Soligen Calcium 10 (Borchers GmbH) drier 0. 25- Octa-Soligen Zirkonium 6 (Borchers GmbH) 2. 33 Octa-Soligen Cobalt 6 (Borchers GmbH) 0. 62 - Octa-Soligen Zink 6 (Borchers GmbH) 0. 57- Lanco Glidd AH (Lubrizol Coating Additives) 0.72 0.72 IRGACURE 819 photoinitiator-2. 0 100. 0 # 100. 0 0 IRGACURE 819: Bis (2,4, 6-trimethylbenzoyl)-phenylphosphineoxide Formulation II comparative A Ingredients % % ! 80. 0 80. 0 Varsol D30 (aliphatic hydrocarbon) solvent 17.5 17,5 Exkin 2 (methylethylketoxim) 0.5 - Octa-Soligen Calcium 10 (Borchers GmbH) 1.0 - Octa-Soligen Zirkonium 6 (Borchers GmbH) 0.6 - Octa-Soligen Cobalt 6 (Borchers GmbH) 0. 4- Irgacure 819 - 2.0 100. 0 100.0 # For evaluation of the drying behavior the above coatings are applied with a 76 um slit coater to glass and the measurement with the BK-Recorder is started under different light sources at once. A needle is put on the wet film and is pushed with a constant speed of 28 cm/6h through the film. The record shows five different phases of the drying process within the first 6 hours after application. For evaluation the end of the phases 1 to 4 are listed. Phase 1 No remaining line (wet film) Phase 2 Smooth remaining line (increased viscosity of the coating) Phase 3 Fringed line (gelatin) Phase 4 Interrupted line or surface marks (crosslinking) Phase 5 No visible marks Picture 1: Different phases of the BK-Recorder measurement. '//. / Phase 1 Phase 3 Phase 5 Phase 4 Phase 2 Phase 4 Drying behaviour Tables 1 and 2 show the drying behavior of the above alkyd systems upon exposure to fluorescent and daylight lamps. The values are given in min.

Tab. 1 Formulation I TL03/20W-lamp Daylight lamp phase phase 1 2 3 4 1 2 3 4 Comparative 48 58 77 113 68 85 98 184 B 8 13 49 171 32 45 129 141 Tab. 2 Formulation II TL03/20W-lamp Daylight lamp phase phase 1 2 3 1 4 1 2 3 4 Comparative 81 109 150 216 45 141 183 226 B 6 13 23 48 31 44 75 107