Curable compositions for printing applications, method for coating a substrate, coating and cured compositions

Abstract

Curable compositions are based on ethoxylated triacrylates and alkylglycidyletheracrylates which can be employed to obtain printing products with a soft touch coating. The curable compositions are processed in conventional printing machines where sheets of glossy and matt paper have the curable compositions applied thereto with an anilox roller and then the paper is dried by UV lamps.

Claims

1. A curable composition, comprising: a) at least one compound of formula (I): ##STR00003## wherein: n is 1 to 20; R.sup.1 is H or methyl; R.sup.2 is H or C.sub.1-C.sub.6-alkyl; b) at least one compound of formula (II): ##STR00004## wherein: m is 1 to 30; R.sup.3 is H or methyl; and c) at least one polymerization initiator.

2. The curable composition according to claim 1, wherein: n is 2 to 15; R.sup.2 is H or C.sub.1-C.sub.3-alkyl; and m is 3 to 20.

3. The curable composition according to claim 1, wherein: n is 5; and m is 12 to 16.

4. The curable composition according to claim 1, wherein a water content of the curable composition is less than 30 weight-% based on the curable composition.

5. The curable composition according to claim 1, wherein: n is 3 to 8; R.sup.2 is H or methyl; and m is 12 to 16.

6. The curable composition according to claim 1, wherein a water content of the curable composition is less than 20 weight-% based on the curable composition.

7. The curable composition according to claim 1, wherein a water content of the curable composition is less than 15 weight-% based on the curable composition.

8. A method for coating a substrate, which comprises the steps of: i) providing a curable composition, containing: a) at least one compound of formula (I): ##STR00005## wherein: n is 1 to 20; R.sup.1 is H or methyl; R.sup.2 is H or C.sub.1-C.sub.6-alkyl; b) at least one compound of formula (II): ##STR00006## wherein: m is 1 to 30; R.sup.3 is H or methyl; and c) at least one polymerization initiator. ii) applying the curable composition to the substrate; and iii) curing the substrate obtained in step ii).

9. The method according to claim 8, wherein the curable composition is applied in a form of a one-part system.

10. The method according to claim 8, wherein the curing of the substrate in step iii) comprises curing by exposure to radiation.

11. The method according to claim 8, wherein the applying step to the substrate in step ii) is effected by printing.

12. The method according to claim 11, wherein the printing is performed by printing with an anilox roller or other roller coaters, flexographic printing, offset printing, gravure printing, letterpress printing, screen printing and combinations thereof.

13. The method according to claim 8, wherein the substrate is selected from the group consisting of paper, paperboard, metals, in particular steel, glass, thermoplastics, composites, wood, leather and combinations thereof.

14. The method according to claim 10, wherein the curing of the substrate in step iii) comprises curing by exposure to visible radiation, UV radiation, electron-beam radiation or microwave radiation.

15. A coating, comprising: a curable composition, containing: a) at least one compound of formula (I): ##STR00007## wherein: n is 1 to 20; R.sup.1 is H or methyl; R.sup.2 is H or C.sub.1-C.sub.6-alkyl; b) at least one compound of formula (II): ##STR00008## wherein: m is 1 to 30; R.sup.3 is H or methyl; and c) at least one polymerization initiator.

16. The coating according to claim 15, where the coating is a soft touch coating.

17. A method for producing a cured composition, comprising: providing a curable composition, containing: a) at least one compound of formula (I): ##STR00009## wherein: n is 1 to 20; R.sup.1 is H or methyl; R.sup.2 is H or C.sub.1-C.sub.6-alkyl; b) at least one compound of formula (II): ##STR00010## wherein: m is 1 to 30; R.sup.3 is H or methyl; and c) at least one polymerization initiator; curing the curable composition resulting in the cured composition.

18. The method according to claim 17, wherein the cured composition is a coating.

19. The method according to claim 17, wherein the cured composition is a soft touch coating.

20. An article, comprising: a curable composition, containing: a) at least one compound of formula (I): ##STR00011## wherein: n is 1 to 20; R.sup.1 is H or methyl; R.sup.2 is H or C.sub.1-C.sub.6-alkyl; b) at least one compound of formula (II): ##STR00012## wherein: m is 1 to 30; R.sup.3 is H or methyl; and c) at least one polymerization initiator; and said curable composition is cured.

Description

BRIEF DESCRIPTION OF THE EXAMPLES

(1) Employed chemicals are:

(2) ethoxylated trimethylolpropanetriacrylate (CAS no. 28961-43-5) (in formula (I): n is 5, R.sup.1 is H, R.sup.2 is methyl), average molecular weight of 956 g/mol, Photomer 4158 from IGM Resins;

(3) C.sub.12-C.sub.16-alkylglycidyletheracrylate (CAS no. 68071-40-9) (in formula (II): m is 12 to 16, R.sup.3 is H), average molecular weight of 334 g/mol, Miramer PE120 from Miwon;

(4) 4-phenylbenzophenone, >99%;

(5) 1-hydroxycyclohexylphenylketone, >99%;

(6) N-methyldiethanolamine;

(7) Fischer Tropsch wax (CAS no. 8002-74-2), average particle size of 5 to 9 m, Glissaspray 8 from Parchvale;

(8) crosslinked polyurethane beads, average particle size of 6 to 9 m, Daiplacoat RHU 5070D from Dainichiseika; and

(9) water, tap water.

Example 1: Preparation of the Curable Composition 1

(10) 56.8 g ethoxylated trimethylolpropanetriacrylate, 20.0 g C.sub.12-C.sub.16-alkylglycidyletheracrylate, 2.0 g 4-phenylbenzophenone, 1.2 g 1-hydroxycyclohexyl-phenylketone and 5.0 g N-methyldiethanolamine were mixed in a mixing vessel made of stainless steel with an internal agitator at a temperature of 45 C. until all solids were fully dissolved. To this mixture were added 5.0 g Fischer Tropsch wax and 10 g crosslinked polyurethane beads. The resulting mixture was mixed until a homogeneous solution was obtained. The solution was filtered through a 200 m filter before further use.

Example 2: Preparation of the Curable Composition 2

(11) 49.4 g ethoxylated trimethylolpropanetriacrylate, 17.4 g C.sub.12-C.sub.16-alkylglycidyletheracrylate, 2.0 g 4-phenylbenzophenone, 1.2 g 1-hydroxycyclohexyl-phenylketone and 5.0 g N-methyldiethanolamine were mixed in a mixing vessel made of stainless steel with an internal agitator at a temperature of 45 C. until all solids were fully dissolved. To this mixture were added 5.0 g Fischer Tropsch wax, 10 g crosslinked polyurethane beads and 10.0 g water. The resulting mixture was mixed until a homogeneous solution was obtained. The solution was filtered through a 200 m filter before further use.

Example 3: Application of the Curable Composition 2 from Example 2

(12) In the printing machine Speedmaster from Heidelberger Druckmaschinen AG, Heidelberg, 5 g/m.sup.2 of the curable composition 2 from example 2 were applied to 1200 sheets of glossy and matt paper with an anilox roller. The coating was dried in the printing machines with three UV lamps. The printing speed was about 10,000 sheets per hour. The drying/coating speed was good, the processing properties in the printing machine were good and no blocking and no foaming occurred. The resulting paper had very good haptic soft touch properties.