Composition for model material

1. A model material composition for shaping a model material by a material jetting optical shaping method, comprising a polymerizable compound, a photopolymerization initiator and a siloxane compound having one polymerizable group per molecule,

wherein the siloxane compound has a number average molecular weight of 300 to 10,000,

wherein the polymerizable group in the siloxane compound is a group selected from the group consisting of an acryloyl group, a methacryloyl group, a vinyl group, an allyl group and a vinyl ether group, and

wherein the model material composition comprises the siloxane compound in an amount of 0.005 to 5% by mass, with respect to a total mass of the model material composition.

2. The model material composition according to claim 1 , wherein, when the model material composition drips and lands on a cured article of the model material composition, a contact angle of a droplet of the model material composition against the cured article as measured 0.3 seconds after the landing is 40° or more.

3. The model material composition according to claim 1 , wherein the model material composition has a surface tension of 24 to 30 mN/m.

4. The model material composition according to claim 1 , wherein the siloxane compound is a siloxane compound having the polymerizable group at one end thereof.

5. The model material composition according to claim 1 , wherein the siloxane compound has a structure represented by formula (1):

wherein:

R 1 represents a hydrogen atom or a methyl group;

R 2 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;

R 3 is selected from the group consisting of (CH 2 ) m , (EO) x , (PO) y and a combination thereof;

m represents a numerical value of 1 to 10;

(EO) represents (C 2 H 4 O);

(PO) represents (C 3 H 6 O);

x and y independently represent a numerical value of 0 to 50; and

n represents a numerical value of 3 to 220.

6. The model material composition according to claim 1 , wherein the polymerizable compound comprises a monofunctional ethylenically unsaturated monomer (A), a polyfunctional ethylenically unsaturated monomer (B) and an oligomer (C).

7. The model material composition according to claim 6 , wherein the model material composition comprises the monofunctional ethylenically unsaturated monomer (A) in an amount of 50% by mass or more, with respect to a total mass of the polymerizable compound.

8. The model material composition according to claim 6 , wherein the model material composition comprises the polyfunctional ethylenically unsaturated monomer (B) in an amount of 1 to 30% by mass, with respect to the total mass of the polymerizable compound.

9. The model material composition according to claim 6 , wherein the model material composition comprises the oligomer (C) in an amount of 1 to 30% by mass, with respect to the total mass of the polymerizable compound.

10. The model material composition according to claim 6 , wherein the monofunctional ethylenically unsaturated monomer (A) is a monofunctional ethylenically unsaturated monomer having a cyclic structure in the molecule thereof.

11. The model material composition according to claim 6 , wherein an SP value of each of the monofunctional ethylenically unsaturated monomer (A) and the polyfunctional ethylenically unsaturated monomer (B) is 11.0 or less.

12. The model material composition according to claim 1 , wherein the model material composition further comprises a coloring agent.

13. A composition set for material jetting optical shaping, comprising the model material composition according to claim 1 and a support material composition for shaping a support material by a material jetting optical shaping method.

14. The composition set for material jetting optical shaping according to claim 13 , wherein the support material composition is soluble in water.

15. A method for producing an optically shaped article using the model material composition according to claim 1 , the method comprising irradiating the model material composition or the composition set with an active energy ray in a wavelength of 320 to 410 nm at an accumulated light amount of 300 mJ/cm 2 or more per layer to cure the model material composition.

16. A method for producing an optically shaped article using the model material composition according to the composition set for material jetting optical shaping according to claim 13 , the method comprising irradiating the model material composition or the composition set with an active energy ray in a wavelength of 320 to 410 nm at an accumulated light amount of 300 mJ/cm 2 or more per layer to cure the model material composition.