Method of making low extractable coatings using radiation curable compositions containing aminoacrylates

1. A method of making a low extractable coating, which comprises:

(a) providing a radiation curable composition comprising:

at least one amino(meth)acrylate,

wherein the amino(meth)acrylate is produced by a method consisting essentially of

reacting at least one primary or secondary amine (A) with at least one (meth)acrylated ethoxylated and propoxylated polyol (B) having a degree of alkoxylation of at least 4 and at least 3 (meth)acrylic groups,

wherein the polyol (B) is a (meth)acrylated ethoxylated and propoxylated polyol having a molar ratio of propoxyl to ethoxyl units of 1:4,

(b) applying said composition onto a surface,

(c) irradiating the surface with actinic radiation or electron beam radiation, and

(d) obtaining the low extractable coating.

2. The method according to claim 1 , wherein the polyol (B) is selected from ethoxylated and propoxylated glycerol tri(meth)acrylates, ethoxylated and propoxylated trimethylolpropane tri(meth)acrylates or ethoxylated and propoxylated pentaerythritol tetra(meth)acrylates.

3. The method according to claim 1 , wherein the polyol (B) is selected from the tetra(meth)acrylates of ethoxylated and propoxylated pentaerythritol having a degree of alkoxylation of 5 to 15.

4. The method according to claim 1 , wherein the amine (A) corresponds to formula (I)

wherein R 1 is an alkyl, optionally substituted by hydroxy, alkoxy, tertiary amine and/or aryl, and, R 2 is hydrogen or an alkyl, optionally substituted by hydroxy, alkoxy, tertiary amine and/or aryl, with the proviso that R 1 and R 2 may be linked together in order to form a ring.

5. The method according to claim 1 , wherein the amine (A) is selected from alkylamines and dialkylamines, wherein the alkyl groups, each independently, comprise from 1 to 12 carbon atoms, optionally substituted by a hydroxy.

6. The method according to claim 1 , wherein the radiation curable composition comprises from 5 to 99% by weight of the amino(meth)acrylate.

7. The method according to claim 1 , wherein the composition further comprises from 1 to 95% by weight of a (meth)acrylated ethoxylated and/or propoxylated polyol (B) having a degree of alkoxylation of at least 4.

8. The method according to claim 1 , wherein the low extractable coating is a low extractable varnish, adhesive or ink.

9. The method according to claim 1 , wherein the amount of the at least one primary or secondary amine (A) is less than 500 ppm after the reaction of the at least one primary or secondary amine (A) with at least one (meth)acrylated ethoxylated and propoxylated polyol (B) having a degree of alkoxylation of at least 4 and at least 3 (meth)acrylic groups is complete.

10. The method according to claim 1 , wherein the amount of the at least one primary or secondary amine (A) is less than 200 ppm after the reaction of the at least one primary or secondary amine (A) with at least one (meth)acrylated ethoxylated and propoxylated polyol (B) having a degree of alkoxylation of at least 4 and at least 3 (meth)acrylic groups is complete.

11. The method according to claim 1 , wherein the at least one primary or secondary amine (A) is stripped from the reaction product of the at least one primary or secondary amine (A) with at least one (meth)acrylated ethoxylated and propoxylated polyol (B) having a degree of alkoxylation of at least 4 and at least 3 (meth)acrylic groups.

12. The method according to claim 1 , wherein the low extractable coating is suitable to be used for food packaging applications.

13. A method of making a low extractable coating, which comprises:

(a) providing a radiation curable composition comprising:

at least one amino(meth)acrylate and from 1 to 95% by weight of a (meth)acrylated ethoxylated and propoxylated polyol (B) having a degree of alkoxylation of at least 4,

wherein the amino(meth)acrylate is produced by a method consisting essentially of

reacting at least one primary or secondary amine (A) with at least one (meth)acrylated ethoxylated and propoxylated polyol (B),

wherein the amine (A) is selected from the group consisting of methylamine, ethylamine, propylamine, butylamine, hexylamine, 2-ethylhexylamine, cyclohexylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, ethanolamine and mixtures thereof,

wherein the polyols (B) are tetra(meth)acrylates of ethoxylated and propoxylated pentaerythritol having a degree of alkoxylation of 5 to 15, wherein a molar ratio of propoxyl toethoxyl units of 1:4, and wherein the molar ratio of amino groups of (A) to (meth)acrylic double bonds of (B) is 0.01:1 to 0.5:1

(b) applying said composition onto a surface,

(c) irradiating the surface with actinic radiation or electron beam radiation, and

(d) obtaining the low extractable coating.

14. The method according to claim 13 , wherein the amine (A) is selected from the group consisting of diethylamine, dipropylamine, butylamine, and ethanolamine.

15. The method according to claim 1 , wherein the amine (A) is selected from the group consisting of methylamine, ethylamine, propylamine, butylamine, hexylamine, 2-ethylhexylamine, cyclohexylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, ethanolamine and mixtures thereof.

16. The method according to claim 15 , wherein the amine (A) is selected from the group consisting of diethylamine, dipropylamine, butylamine, and ethanolamine.

17. The method according to claim 1 , wherein the molar ratio of amino groups of (A) to (meth)acrylic double bonds of (B) is 0.01:1 to 0.5:1.

18. The method according to claim 1 , wherein the amount of the at least one primary or secondary amine (A) is less than 1000 ppm after the reaction of the at least one primary or secondary amine (A) with at least one (meth)acrylated ethoxylated and propoxylated polyol (B) having a degree of alkoxylation of at least 4 and at least 3 (meth)acrylic groups is complete.