Search

US-20260125564-A1 - CURABLE RESIN COMPOSITION FOR STEREOLITHOGRAPHY, CURED PRODUCT, AND THREE-DIMENSIONAL SHAPED OBJECT

US20260125564A1US 20260125564 A1US20260125564 A1US 20260125564A1US-20260125564-A1

Abstract

A curable resin composition for stereolithography capable of forming an optical three-dimensional shaped object having both sufficient toughness and heat resistance, a cured product of the composition, and a three-dimensional shaped object are provided. The curable resin composition contains a urethane resin (A) having two (meth)acryloyl groups, an α,β-unsaturated carbonyl compound (B), and a photopolymerization initiator. The urethane resin (A) is obtained by using, as reaction raw materials a polycarbonate diol (a1), a diisocyanate (a2), and a compound (a3) having a hydroxyl group and a (meth)acryloyl group. The polycarbonate diol (a1) has a branched or linear aliphatic structure. The α,β-unsaturated carbonyl compound (B) has a glass transition temperature (Tg) of 50° C. or higher when formed into a polymer. The urethane resin (A) has a number average molecular weight (Mn) of 2000 or more.

Inventors

  • Shoko Nishida
  • Takashi Nishijima
  • Yoshinobu Deguchi
  • Takayuki Miki

Assignees

  • DIC CORPORATION

Dates

Publication Date
20260507
Application Date
20251106
Priority Date
20241107

Claims (10)

  1. 1 . A curable resin composition for stereolithography, comprising: a urethane resin (A) having two (meth)acryloyl groups; an α,β-unsaturated carbonyl compound (B); and a photopolymerization initiator wherein, the urethane resin (A) is obtained by using, as reaction raw materials, a polycarbonate diol (a1), a diisocyanate (a2), and a compound (a3) having a hydroxyl group and a (meth)acryloyl group, the polycarbonate diol (a1) has a branched or linear aliphatic structure, the α,β-unsaturated carbonyl compound (B) has a glass transition temperature (Tg) of 50° C. or higher when formed into a polymer, and the urethane resin (A) has a number average molecular weight (Mn) of 2000 or more.
  2. 2 . The curable resin composition for stereolithography according to claim 1 , further comprising a compound (C) having two or more (meth)acryloyl groups wherein, the compound (C) having two or more (meth)acryloyl groups has a glass transition temperature (Tg) of 60° C. or higher when formed into a polymer.
  3. 3 . The curable resin composition for stereolithography according to claim 1 , wherein the α,β-unsaturated carbonyl compound (B) is a compound having one (meth)acryloyl group.
  4. 4 . The curable resin composition for stereolithography according to claim 1 , wherein a content of the (meth)acryloyl groups in the urethane resin (A) is 0.3 mmol/g or more and 2.0 mmol/g or less.
  5. 5 . The curable resin composition for stereolithography according to claim 1 , wherein a content of the urethane resin (A) is 1 mass % or more and 50 mass % or less.
  6. 6 . The curable resin composition for stereolithography according to claim 1 , wherein a content of the α,β-unsaturated carbonyl compound (B) is 20 mass % or more and 90 mass % or less.
  7. 7 . The curable resin composition for stereolithography according to claim 2 , wherein a content of the compound (C) having two or more (meth)acryloyl groups, when the compound (C) is contained, is 1 mass % or more and 50 mass % or less.
  8. 8 . The curable resin composition for stereolithography according to claim 1 , wherein the urethane resin (A) is a resin represented by Formula (1) described below: (In Formula (1), R 1 and R 7 each independently represent a hydrogen atom or a methyl group, R 2 and R 6 each independently represent —C 2 H 4 —, —C 3 H 6 —, —C 4 H 8 —, or —C 2 H 4 O(COC 5 H 10 ) s — (s=from 1 to 4), R 3 and R 5 each independently represent —C 5 H 10 —, —C 6 H 12 —, —C 10 H 18 —, or —C 9 H 18 —, R 4 represents one or two or more divalent groups selected from the group consisting of —(CH 2 ) s — (s=from 2 to 12) and —(CH 2 ) s —CH(CH 3 )—(CH 2 ) t — (s and t are optionally 0, and s+t=from 0 to 10), and n represents an integer of from 2 to 100.
  9. 9 . A cured product which is a cured reaction product of the curable resin composition for stereolithography described in claim 1 .
  10. 10 . A three-dimensional shaped object comprising the cured product described in claim 9 .

Description

TECHNICAL FIELD The present invention relates to a curable resin composition for stereolithography, a cured product, and a three-dimensional shaped object. BACKGROUND ART In recent years, as a method for producing a resin molded article, an optical three-dimensional shaping method (stereolithography) has been used in which a three-dimensional shaped object is fabricated by selectively polymerizing and curing a curable resin composition with an active energy ray such as an ultraviolet laser based on three-dimensional shape data designed by a three-dimensional design system such as a three-dimensional CAD. The optical three-dimensional shaping method can cope with a complicated shape which is difficult to be formed by cutting, and is short in manufacturing time and easy to handle, and therefore, has come to be widely used for manufacturing a prototype model of an industrial product in addition to a resin molded article. A typical example of the optical three-dimensional shaping method includes a method of obtaining a three-dimensional shaped object by repeating the following operations: irradiating a liquid photocurable resin put in a container with a spot-shaped ultraviolet laser controlled by a computer from above to cure one layer having a predetermined thickness; lowering the shaped object by one layer to supply the liquid resin on the layer; similarly irradiating the resin with an ultraviolet laser beam to cure the resin; and laminating the cured resin. In addition to the above-described stippling method using a spot-shaped ultraviolet laser, the number of surface exposure methods has been recently increased in which a light source other than a laser such as an LED is used, ultraviolet light is emitted from below through a transparent container containing a photocurable resin via a planar drawing mask called a digital micromirror device (DMD) in which a plurality of digital micromirror shutters are arranged in a planar shape to cure one layer of a predetermined cross-sectional shape pattern, the shaped object is pulled up by one layer, the next layer is irradiated and cured in the same manner as described above, and the layers are sequentially laminated to obtain a three-dimensional shaped object. The above-described optical three-dimensional shaping method (stereolithography) has been actively developed because of its high shaping speed and high accuracy (see, for example, Patent Documents 1 and 2). As a result, along with improvement of stereolithography machines and stereolithography materials, an application range of the stereolithography is expanding from a prototype to a final product. However, in the case of automobile parts, household electrical appliance parts, and the like, an optical three-dimensional shaped object having both sufficient toughness and heat resistance as a final product has not been obtained by the existing techniques. Therefore, a curable resin composition for stereolithography capable of forming an optical three-dimensional shaped object having both sufficient toughness and heat resistance has been required. CITATION LIST Patent Documents Patent Document 1: JP 2019-199448 APatent Document 2: WO 2022/209689 SUMMARY OF INVENTION Technical Problem An object of the present invention is to provide a curable resin composition for stereolithography capable of forming an optical three-dimensional shaped object having both sufficient toughness and heat resistance, a cured product thereof, and a three-dimensional shaped object. Solution to Problem The present invention encompasses the following aspects. [1]A curable resin composition for stereolithography, containing: a urethane resin (A) having two (meth)acryloyl groups;an α,β-unsaturated carbonyl compound (B); anda photopolymerization initiator, wherein the urethane resin (A) is obtained by using, as reaction raw materials, a polycarbonate diol (a1), a diisocyanate (a2), and a compound (a3) having a hydroxyl group and a (meth)acryloyl group,the polycarbonate diol (a1) has a branched or linear aliphatic structure, the α,β-unsaturated carbonyl compound (B) has a glass transition temperature (Tg) of 50° C. or higher when formed into a polymer, andthe urethane resin (A) has a number average molecular weight (Mn) of 2000 or more. [2] The curable resin composition for stereolithography according to [1], further containing a compound (C) having two or more (meth)acryloyl groups, whereinthe compound (C) having two or more (meth)acryloyl groups has a glass transition temperature (Tg) of 60° C. or higher when formed into a polymer. [3] The curable resin composition for stereolithography according to [1] or [2], wherein the α,β-unsaturated carbonyl compound (B) is a compound having one (meth)acryloyl group. [4] The curable resin composition for stereolithography according to any of [1] to [3], wherein a content of the (meth)acryloyl groups in the urethane resin (A) is 0.3 mmol/g or more and 2.0 mmol/g or less. [5] The curable resin composition