Radiation curable composition

1. A radiation curable composition comprising:

(a) 15 to 85 wt % of at least one solvent comprising ≦20 wt % of water;

(b) 5 to 50 wt % of at least one radiation curable material having a Mn in the range of from 50 to 10,000 g/mol and an average acrylate functionality in the range of from 2 to 6;

(c) 10 to 70 wt % of at least one polyurethane having

(i) a Mw in the range of from 4,000 to 70,000 g/mol;

(ii) 0 to 1.5 wt % of isocyanate-reactive component(s) bearing ionic or potentially ionic water-dispersing groups; and

(iii) a free isocyanate group content <0.5 wt %;

wherein the at least one solvent (a) comprises ≧74 wt. % solvents having an evaporation rate ≧1.0 in relation to butyl acetate having an evaporation rate of 1.0; and

wherein the composition has solids content of 25 to 85 wt. %; and

wherein (a), (b) and (c) add up to 100%; and

wherein the ratio of (b) to (c) is in the range of from 9/91 to 40/60.

2. A composition according to claim 1 wherein the radiation curable material (b) is a UV curable material.

3. A composition according to claim 1 wherein the polyurethane (c) has a viscosity ≦18,000 mPa s at any solids content in the range of from 20 to 60 wt %, in a solvent comprising ≧70 wt % of at least one solvent having a molecular weight ≦105 g/mol.

4. A composition according to claim 1 comprising:

(a) 15 to 85 wt % of at least one solvent comprising ≦1 wt % of water;

(b) 5 to 50 wt % of at least one radiation curable material having:

(i) a Mn in the range of from 550 to 3500 g/mol; and

(ii) an average acrylate function in the range of from 2 to 5;

(c) 10 to 70 wt % of at least one polyurethane having:

(i) a Mw in the range of from 6,000 to 55,000 glmol;

(ii) 0 to 1.5 wt % of isocyanate-reactive component(s) bearing ionic or potentially ionic water-dispersing groups;

(v) a non-detectable free isocyanate group content; and

(vi) 0 to 0.1 mol of CC bonds per 100 g; and

wherein (a), (b) and (c) add up to 100%; where the ratio of (b) to (c) is in the range of from 14/86 to 35/65.

5. A composition according to claim 1 wherein the polyurethane is obtained by the reaction of components:

(i) 5 to 50 wt % of at least one polyisocyanate;

(ii) 0 to 20 wt % of at least one isocyanate-reactive component having a Mw in the range of from 50 to 200 g/mol;

(iii) 0 to 90 wt % of at least one isocyanate-reactive component having a Mw in the range of from 201 to 20,000 g/mol;

(iv) 0 to 95 wt % of at least one isocyanate-reactive component not comprised by (ii) or (iii); and

(v) 0 to 40 wt % of at least one chain-extending and/or chain-terminating component not comprised by (i), (ii), (iii) or (iv);

wherein (i), (ii), (iii),(iv) and (v) add up to 100%; in the presence of a solvent; and

wherein the components comprise 0 to 1.5 wt % of isocyanate-reactive component(s) bearing ionic or potentially ionic water-dispersing groups.

6. A composition according to claim 1 having a resolubility within 30 seconds.

7. An adhesive comprising a composition according to claim 1 .

8. An ink comprising:

(a) 15 to 84 wt % of at least one solvent comprising ≦20 wt % of water;

(b) 5 to 50 wt % of at least one radiation curable material having an Mn in the range of from 50 to 10,000 g/mol and an average acrylate functionality in the range of from 2 to 6;

(c) 10 to 70 wt % of at least one polyurethane:

(i) having a Mw in the range of from 4,000 to 70,000 g/mol;

(ii) having 0 to 1.5 wt % of isocyanate-reactive component(s) bearing ionic or potentially ionic water-dispersing groups; having a free isocyanate group content 0.5 wt %; and

(d) 0.1 to 50 wt % of at least one colorant;

wherein (a), (b), (c) and (d) add up to 100%; and

wherein the at least one solvent (a) comprises ≧74 wt. % solvents having an evaporation rate ≧1.0 in relation to butyl acetate having an evaporation rate of 1.0; and

wherein the composition has solids content of 25 to 85 wt. %; and

wherein the ratio of (b) to (c) is in the range of from 9/91 to 40/60.

9. An ink according to claim 8 comprising ≦10 wt % of water.

10. An ink according to claim 8 having a viscosity in the range of from 50 to 1,000 mPa s.

11. A process for printing an image on a substrate comprising applying thereto an ink according to claim 8 .

12. A flexographic printing process comprising applying an ink according to claim 8 to a substrate.

13. A gravure printing process comprising applying an ink according to claim 8 to a substrate.

14. A gravure printing process comprising applying an ink according to claim 9 to a substrate.