JPH06287241A - Photopolymerizable composition for optically three-dimensional shaping - Google Patents

Abstract

PURPOSE:To obtain the subject composition, comprising a specific unsaturated urethane, an acrylic or a methacrylic acid ester and a photopolymerization initiator and capable of simultaneously achieving the improvement in photopolymerization reactivity and. thermal properties of cured and shaped products and the reduction in reactional shrinkage in photopolymerizing reaction. CONSTITUTION:The objective composition comprises (A) an unsaturated urethane selected from formulas I and II {X<1> and X<2> are residues after removing hydroxyl groups from tri-or tetravalent polyols; Y is residue after removing NCO from diisocyanate; R<1> and R<4> are H or CH3, with the proviso that both are not simultaneously the same; R<2> and R<6> are 5-21C aliphatic hydrocarbon; R<3> is 2-4C alkylene; R<5> and R<8> are H or CH3, with the proviso that both are not simultaneously the same; R<7> is 2-6C alkylene or polyalkylene glycol residue having a 2 or 3C alkylene; p to u are 1 or 2, with the proviso that [p+q+r] is 3 or 4; [s+t+u] is 3 or 4}, (B) an acrylic or a methacrylic acid ester copolymerizable with the component (A) and (C) a photopolymerization initiator at (10/90) to (90/10) weight ratio of the components (A)/(B).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photopolymerizable composition for optical three-dimensional modeling (hereinafter simply referred to as a photopolymerizable composition). The NC cutting method is used for manufacturing various models and fixed objects such as a model for mold making, a model for copying, a model for die-sinking electric discharge machining, etc. Attention has been focused on a method of irradiating a photopolymerizable composition with an energy ray to cure it into a predetermined shape. The present invention relates to a photopolymerizable composition applied to the above-described optical three-dimensional molding method, which is a photopolymerizable composition containing an unsaturated urethane having a specific structure.

[0002]

2. Description of the Related Art Conventionally, as a photopolymerizable composition containing an unsaturated urethane, 1) an example containing an unsaturated urethane obtained from a polyurethane diisocyanate and a hydroxyalkyl acrylate (JP-A-2-145616),
2) Example containing unsaturated urethane obtained from polyurethane diisocyanate and triol di (meth) acrylate (JP-A-1-204915, JP-A-63-355)
50) 3) Example containing unsaturated urethane obtained from polyurethane diisocyanate and tetraol triacrylate (JP-A-61-276863), 4) Polyurethane obtained from tri-hexaisocyanate and triol di (meth) acrylate. Example containing saturated urethane (JP-A-63-35550), 5) Example containing unsaturated urethane obtained from triisocyanate and diol mono (meth) acrylate or triol di (meth) acrylate (JP-A-63-112551) ), 6)
Example containing unsaturated urethane obtained from diisocyanate and triol dimethacrylate (Japanese Patent Publication No. 63-2
0203).

However, the above conventional example has the following drawbacks. In the case of the above-mentioned conventional examples 1) to 5), when the double bond concentration in the photopolymerizable composition is increased to increase the crosslink density of the obtained cured shaped article, the reaction shrinkage in the photopolymerization reaction is increased. On the contrary, if the concentration of the double bond in the photopolymerizable composition is lowered to attempt to reduce the crosslink density of the obtained cured shaped article, it is inferior in thermal physical properties, for example, only a cured shaped article having a low heat distortion temperature. I can't get it. Further, in the case of the conventional example of the above 6), since the concentration of double bonds in the photopolymerizable composition is originally high, the reaction shrinkage in the photopolymerization reaction is remarkably large, and moreover, it is caused by having a polymerizable group composed of a methacryl group. And the photopolymerization reactivity is low. In the conventional example, improvement in photopolymerization reactivity, reduction in reaction shrinkage in the photopolymerization reaction, and improvement in thermal physical properties of the obtained cured shaped article cannot be achieved at the same time.

[0004]

The problems to be solved by the present invention are to improve the photopolymerization reactivity, to reduce the reaction shrinkage in the photopolymerization reaction, in a conventional photopolymerizable composition containing an unsaturated urethane. This is a point that improvement of the thermal physical properties of the obtained cured molded article cannot be achieved at the same time.

[0005]

However, the present inventors have
Regarding the photopolymerizable composition containing an unsaturated urethane, the result of studying the relationship between the chemical structure of the unsaturated urethane, the photopolymerization reactivity, the reaction shrinkage in the photopolymerization reaction, and the thermal physical properties of the obtained cured molded article, An unsaturated urethane having a specific structure in which a polymerizable group composed of an acryloyl group and a methacryloyl group and a hydrophobic group containing a long-chain aliphatic hydrocarbon residue are introduced in a predetermined amount as an unsaturated urethane, and a predetermined ratio thereof is used together therewith. It was found that it is correct and suitable to use a (meth) acrylic acid ester.

That is, the present invention comprises one or more unsaturated urethanes selected from unsaturated urethanes represented by the following formula 1 and unsaturated urethanes represented by the following formula 2.
It is composed of a (meth) acrylic acid ester copolymerizable with the unsaturated urethane and a photopolymerization initiator, and the unsaturated urethane / the (meth) acrylic acid ester = 10/90 to 9
The present invention relates to a photopolymerizable composition characterized by comprising a ratio of 0/10 (weight ratio).

[0007]

[Formula 1]

[0008]

[Formula 2]

[In the formulas 1 and 2, X ¹ and X ² are residues obtained by removing a hydroxyl group from a tri- or tetravalent polyol Y: Residues obtained by removing an isocyanate group from a diisocyanate R ¹ and R ^{4 are the} same at the same time. H or CH ₃ R ^2, R ⁶ should not: aliphatic 5 to 21 carbon atoms hydrocarbon group R ^3: an alkylene group R ⁵ from 2 to 4 carbon atoms, R ^8: not the same at the same time H or CH ₃ R ⁷ : an alkylene group having 2 to 6 carbon atoms or a polyalkylene glycol residue having 2 or 3 carbon atoms in the alkylene group, p, q, r: 1 or 2, and satisfying p + q + r = 3 or 4 s , t, u: 1 or 2 and satisfy s + t + u = 3 or 4]

For the unsaturated urethane represented by the formula 1, 1)
Urethane compounds obtained by reacting a methacrylic acid / long-chain fatty acid mixed partial ester of a polyol derived from a tri- or tetravalent polyol, methacrylic acid, and a long-chain fatty acid with acryloyloxyalkyl isocyanate, 2) 3
Alternatively, a urethane compound obtained by reacting an acrylic acid / long-chain fatty acid mixed partial ester of a polyol derived from a tetravalent polyol, acrylic acid, and a long-chain fatty acid with methacryloyloxyalkyl isocyanate is included.

Methacrylic acid / long-chain fatty acid mixed partial ester of polyol and acrylic acid / long-chain fatty acid mixed partial ester of polyol are collectively referred to as (meth) acrylic acid / long-chain fatty acid mixed partial ester of polyol. ) As a tri- or tetravalent polyol used for deriving a mixed partial ester of acrylic acid / long-chain fatty acid, 1) trivalent alcohols such as glycerin, trimethylolethane and trimethylolpropane, and 2) pentaerythritol such as 4 Polyhydric alcohols, 3) polyether polyols obtained by adding alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to these trihydric or tetrahydric alcohols, and 4) these trihydric or tetrahydric alcohols such as caprolactone and butyrolactone. Aliphatic rac Polyester polyols obtained by adding the emissions and the like.

The long-chain fatty acid used for deriving the (meth) acrylic acid / long-chain fatty acid mixed partial ester of polyol is a saturated or unsaturated fatty acid having 6 to 22 carbon atoms and having a straight chain or a branched chain. . Examples of such long-chain fatty acids include 1) linear saturated fatty acids such as hexanoic acid, octanoic acid, dodecanoic acid and stearic acid, 2) isooctanoic acid,
Examples include branched saturated fatty acids such as isopalmitic acid and isostearic acid, 3) unsaturated fatty acids such as oleic acid and elaidic acid, and mixtures thereof.

As a method for synthesizing a mixed partial ester of (meth) acrylic acid / long-chain fatty acid of polyol, direct esterification reaction of polyol, (meth) acrylic acid and long-chain fatty acid, long-chain fatty acid glycidyl ester and (meth) Examples of the ring-opening addition reaction with acrylic acid, the ring-opening addition reaction with glycidyl (meth) acrylate and a long-chain fatty acid and the like, the present invention is not particularly limited to such a synthetic method, in any of the synthetic method The binding molar ratio of (meth) acrylic acid and long-chain fatty acid is determined so that at least one free hydroxyl group remains for 1 mol of the polyol.

The (meth) polyol thus synthesized
As a mixed partial ester of acrylic acid / long-chain fatty acid,
1) Mixed partial ester of trihydric alcohol such as glycerin monomethacrylate / monoisopalmitate, trimethylolpropane monomethacrylate / monolaurate, 5-methyl-1,2,4-heptanetriol monomethacrylate / monooleate, 2 ) Pentaerythritol monomethacrylate monooleate, pentaerythritol diacrylate mono-2-ethylhexoate, pentaerythritol monomethacrylate dilaurate and other mixed partial esters of tetravalent alcohols,
3) Trimethylolpropane mono (2-hydroxyethyl) ether monomethacrylate / monoisononanoate, polyethoxylated trimethylolpropane monoacrylate / monooctanoate, pentaerythritol monomethacrylate / didecanoate with ring-opening addition of ε-caprolactone, etc. Mixed partial ester of polyether polyol or polyester polyol. Among these, glycerin mono (meth) acrylic acid obtained by a ring-opening addition reaction of a long-chain fatty acid glycidyl ester with (meth) acrylic acid or a ring-opening addition reaction of a glycidyl (meth) acrylate with a long-chain fatty acid Mono-long-chain fatty acid mixed partial esters can be advantageously used.

The (meth) acryloyloxyalkyl isocyanate to be reacted with the (meth) acrylic acid / long-chain fatty acid mixed partial ester of polyol is a (meth) acryloyloxyalkyl isocyanate having an alkyl group having 2 to 4 carbon atoms. As such (meth) acryloyloxyalkyl isocyanate, acryloyloxyethyl isocyanate, acryloyloxy-2-methyl-ethyl isocyanate, methacryloyloxyethyl isocyanate, methacryloyloxy-2-methyl-
Examples thereof include ethyl isocyanate, and of these, methacryloyloxyethyl isocyanate and acryloyloxyethyl isocyanate can be advantageously used.

For the unsaturated urethane represented by the formula 2, 1)
A urethane compound obtained by reacting the above-mentioned partial ester of acrylic acid / long-chain fatty acid mixed polyol with an unsaturated urethane monoisocyanate in which 1 mol of diisocyanate and 1 mol of diol monomethacrylate are urethane-formed, 2) the above-mentioned polyol A urethane compound obtained by reacting a mixed partial ester of methacrylic acid / long-chain fatty acid with 1 mol of diisocyanate and 1 mol of diol monoacrylate to form an urethane-unsaturated urethane monoisocyanate is included.

The diol monomethacrylate and diol monoacrylate used for obtaining the unsaturated urethane monoisocyanate are collectively referred to as diol mono (meth) acrylate. The diol mono (meth) acrylate is 1) 2-hydroxyethyl (meth). Alkanediol mono (meth) acrylates such as acrylate, hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, 2) diethylene glycol mono (meth) acrylate, tripropylene Polyalkylene glycol mono (meth) having 2 or 3 carbon atoms in alkylene group such as glycol mono (meth) acrylate
An acrylate is mentioned. Among these, 2-hydroxyethyl (meth) acrylate is preferable as the alkanediol mono (meth) acrylate, and one having an oxyalkylene group condensation number of 5 or less is preferable as the polyalkylene glycol mono (meth) acrylate.

The diisocyanates used to obtain unsaturated urethane monoisocyanates include 1) various tolylene diisocyanates, aromatic diisocyanates such as methylene-bis- (4-phenylisocyanate), and 2).
Hexamethylene diisocyanate, methylene-bis-
Aliphatic or alicyclic diisocyanate such as (4-cyclohexyl isocyanate), 3) 4-isocyanatomethyl-1-isocyanato-1-methyl-cyclohexane, 5
-Isocyanatomethyl-1-isocyanato-1,1-dimethyl-5-methyl-cyclohexane (isophorone diisocyanate) and other aliphatic / alicyclic diisocyanates may be mentioned. Among these, a diisocyanate having both an isocyanate group affected by a sterically hindering substituent and an isocyanate group not affected in the molecule, an isocyanate group directly bonded to an aliphatic hydrocarbon group in the molecule and an aromatic group A diisocyanate having both an isocyanate group directly bonded to a hydrocarbon group is preferable. Examples of the diisocyanate include 2,4-tolylene diisocyanate, isophorone diisocyanate, 4-isocyanatomethyl-1-isocyanato-1-methyl-cyclohexane and the like.

The present invention does not particularly limit the method for synthesizing unsaturated urethane, and a known method, for example, the method described in JP-A-4-53809 can be applied to the synthesis.

The present invention provides a photopolymerizable composition capable of improving the photopolymerization reactivity and the thermal physical properties of the obtained cured shaped article. Therefore, in the present invention, unsaturated urethane having both an acryloyl group and a methacryloyl group as a polymerizable group is used. Having two different kinds of polymerizable groups is extremely effective in improving the photopolymerization reactivity and the thermal physical properties of the obtained cured shaped article. The relationship between the number of the polymerizable groups contained in one molecule of the unsaturated urethane and the molecular weight of the unsaturated urethane per one polymerizable group also affects the improvement of the photopolymerization reactivity and the thermal physical properties. Unsaturated urethanes preferable for obtaining practically suitable photopolymerization reactivity and thermal properties have a molecular weight of 150 to 45 per polymerizable group.
0, more preferred unsaturated urethane is the polymerizable group 1
The molecular weight per unit is 200 to 400.

The present invention also provides a photopolymerizable composition capable of reducing the reaction shrinkage in the photopolymerization reaction. Therefore, in the present invention, a long-chain aliphatic hydrocarbon group having 5 to 21 carbon atoms is introduced into the molecule of unsaturated urethane. The long-chain aliphatic hydrocarbon group has 7 to 7 carbon atoms.
An alkyl group having 17 and an alkenyl group having 16 to 19 carbon atoms are preferable. The number of long-chain aliphatic hydrocarbon groups to be introduced is one in the case of unsaturated urethane using a trivalent polyol as a raw material, and one in the case of unsaturated urethane using a tetravalent polyol as a raw material. Alternatively, the number of long-chain aliphatic hydrocarbon groups in one molecule of unsaturated urethane is preferably 10 to 45% by weight, and more preferably 15 to 40% by weight.

Examples of the (meth) acrylic acid ester used in combination with the unsaturated urethane represented by the formula 1 or formula 2 are: 1) butyl acrylate, 2-ethylhexyl acrylate and other alkyl acrylates, 2) methyl methacrylate, methacryl Ethyl methacrylate, alkyl methacrylate such as isobutyl methacrylate, 3) ethylene glycol diacrylate, 1,
Dihydric alcohol diacrylate such as 4-butanediol diacrylate, 4) dihydric alcohol dimethacrylate such as 1,2-propylene glycol dimethacrylate and 1,6-hexanediol dimethacrylate,
5) Trihydric alcohol triacrylates such as glycerin triacrylate and trimethylolpropane triacrylate; 6) Trihydric alcohol trimethacrylates such as glycerin trimethacrylate and trimethylolethane trimethacrylate; 7) Trimethylolpropane diacrylate. Mixed (meth) acrylates of trihydric alcohols such as monomethacrylate and glycerin monoacrylate / dimethacrylate, 8) pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, pentaerythritol diacrylate
Tetraester of tetrahydric alcohol such as dimethacrylate, 9) Polyether polyol obtained by adding alkylene oxide such as ethylene oxide, propylene oxide or butylene oxide to the above-mentioned dihydric or tetrahydric alcohol, acrylic acid, methacrylic acid, or a mixture thereof. Esters of polyether polyols obtained from acids, 10)
Examples thereof include esters of polyester polyols obtained from polyester polyols obtained by adding aliphatic lactones such as caprolactone and butyrolactone to the above-mentioned dihydric to tetrahydric alcohols, acrylic acid, methacrylic acid, and mixed acids thereof.

As the (meth) acrylic acid ester as exemplified above, it is preferable to use a mixture of an acrylic acid ester and a methacrylic acid ester, and a mixed unsaturated acid ester obtained from a polyol and acrylic acid and methacrylic acid is used. It is more preferable to use. In this case, the ratio of acrylic group and methacrylic group is preferably acrylic group / methacrylic group = 9/1 to 1/9 (molar ratio) in both the mixture and the mixed unsaturated acid ester. / 2 to 5/5 (molar ratio) is more preferable.

In the photopolymerizable composition of the present invention, an unsaturated urethane can be copolymerized with the unsaturated urethane (meth).
The ratio of the acrylic ester is the unsaturated urethane / the (meth) acrylic ester = 10/90 to 90/10.
(Weight ratio), preferably 30/70 to 70/30
(Weight ratio). Both ratio is 10/90 (weight ratio)
If it is less than 90%, the physical properties of the cured shaped product obtained by the photopolymerization reaction are inferior. On the contrary, if it exceeds 90/10 (weight ratio), the viscosity of the photopolymerizable composition becomes too high, and the optical shaping operation becomes difficult.

The photopolymerizable composition of the present invention comprises an unsaturated urethane, a (meth) acrylic acid ester and a photopolymerization initiator. The present invention does not limit the kind of the photopolymerization initiator to be used, but examples of the photopolymerization initiator include 1) carbonyl compounds such as benzoin, α-methylbenzoin, anthraquinone, chloroanthraquinone and acetophenone, and 2) diphenyl. Examples thereof include sulfur compounds such as sulfides, diphenyl disulfides and dithiocarbamates, and 3) polycyclic aromatic compounds such as α-chloromethylnaphthalene and anthracene. The content of these photopolymerization initiators in the photopolymerizable composition is such that the total amount of unsaturated urethane and (meth) acrylic acid ester is 100.
It is usually 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight with respect to parts by weight. A photosensitizer such as n-butylamine, triethanolamine, N, N-dimethylaminobenzenesulfonic acid diallylamide, or N, N-dimethylaminoethyl methacrylate can be used together with the photopolymerization initiator.

The photopolymerizable composition of the present invention comprises an unsaturated urethane, a (meth) acrylic acid ester and a photopolymerization initiator. For the purpose of further reducing the reaction shrinkage due to curing during photopolymerization of the same. In addition to these, solid fine particles having an average particle diameter of 0.1 to 50 μm and an average fiber length of 1 to 70
A filler selected from inorganic fiber whiskers having a diameter of μm can be contained. When solid fine particles are used as the filler, those having an average particle diameter of 1 μm or less are preferable, and those having an average particle diameter of 0.3 μm or less are more preferable. Examples of the filler include 1) inorganic particles such as silica, alumina, clay and calcium carbonate, 2) metal particles such as aluminum and iron, 3) polyamide, vinyl chloride and vinyl acetate,
Styrene-divinylbenzene copolymer, organic polymer fine particles such as polymethylmethacrylate, 4) Solid fine particles such as polyorganosiloxane fine particles such as polymethylsilsesquioxane and polysiloxane-polyvinyl graft polymer, 5) Potassium titanate There are inorganic fiber whiskers such as fibers, magnesium sulfate fibers, and carbon fibers. When these fillers are contained, the total amount of unsaturated urethane and (meth) acrylic acid ester is 100 parts by weight,
It is usually 300 parts by weight or less, preferably 1 to
It should be 100 parts by weight. 1 of these fillers
One kind or a mixture of two or more kinds can be used.

The present invention does not particularly limit the optical stereolithography method to which the photopolymerizable composition of the present invention is applied. Various methods are known as optical three-dimensional modeling methods (Japanese Patent Laid-Open No. 56-144478, Japanese Patent Laid-Open No. 60-247515, Japanese Patent Laid-Open No. 1-204915, Japanese Patent Laid-Open No. 3-41126, etc.). After forming a cured layer on, the uncured composition is supplied onto the cured layer, and the operation of irradiating this with an energy ray to form the next cured layer is repeated to obtain a desired cured molded article. There is a method of forming and further post-curing if necessary. Examples of energy rays used include visible rays, ultraviolet rays, and electron rays, and ultraviolet rays are preferable.

[0028]

【Example】

Test Category 1 (Preliminary Synthesis) Preliminary Synthesis Examples 1 to 4 shown below were performed. In each preliminary synthesis example, parts are parts by weight. Preliminary Synthesis Example 1 144 parts (1.0 mol) of octanoic acid and 2 parts of triethylamine as a catalyst were placed in a reaction vessel, kept at 70 ° C. and stirred, and 142 parts of glycidyl methacrylate (1.
(0 mol) was added dropwise over 30 minutes. Then, set the reaction system to 7
The synthesis was completed by holding at 0 ° C for 5 hours. The oxirane oxygen content of the reaction product was quantified, but was hardly detected. The product obtained here is 286 parts of glycerin monomethacrylate monooctanoate with an acid number of 0.
7, the hydroxyl value was 198, and the saponification value was 390.

Preliminary Synthesis Example 2 The same procedure as in Preliminary Synthesis Example 1 was carried out using 200 parts (1.0 mol) of lauric acid, 3 parts of triethylamine and 128 parts (1.0 mol) of glycidyl acrylate. The product obtained here was 328 parts of glycerin monoacrylate monolaurate, and had an acid value of 0.9, a hydroxyl value of 172, and a saponification value of 343.

Preliminary Synthesis Example 3 200 parts (1.0 mol) of glycerin diacrylate and 3 parts of boron trifluoride ether complex as a catalyst were placed in a reaction vessel, kept at 70 ° C. and stirred, and 338 parts of glycidyl oleate. (1.0 mol) was added dropwise over 30 minutes. Then, the reaction system was kept at 70 ° C. for 5 hours to complete the synthesis. The oxirane oxygen was quantified for the reactants,
Almost not detected. The product obtained here was 537 parts of diglycerin diacrylate monooleate, and had an acid value of 0.2, a hydroxyl value of 105, and a saponification value of 314.

Preliminary Synthesis Example 4 58 parts (0.5 mol) of 2-hydroxyethyl acrylate, 150 parts of dry toluene and 0.2 part of tetrabutyl titanate as a catalyst were placed in a reaction vessel, kept at 80 ° C. and stirred, Furthermore, 442 parts of ε-caprolactone (3.9
Mol) was added dropwise over 30 minutes. Then, the reaction system was changed to 10
The synthesis was completed by holding at 0 ° C. for 1 hour. Toluene was distilled off from the reaction system under reduced pressure to obtain 495 parts of 2-hydroxyethyl acrylate ε-caprolactone adduct.

Test Category 2 (Synthesis of Unsaturated Urethane and Preparation of Monomer Solution) The following synthesis of unsaturated urethane and preparation of a monomer solution were carried out. The types and amounts of the raw materials used in the synthesis are summarized in Table 1, and the contents of the unsaturated urethane obtained are summarized in Table 2. In the synthesis of each unsaturated urethane and the preparation of the monomer solution, parts are parts by weight and% is% by weight. -Synthesis of unsaturated urethane A-1 and monomer solution a-1
143 parts (0.5 mol) of glycerin monomethacrylate monooctanoate obtained in Preparative Synthesis Example 1, 214 parts of polyethylene glycol (molecular weight 200) diacrylate and 0.5 part of di-n-butyltin dilaurate were reacted. Transfer to a container, hold at 50 ° C and stir, and further add 71 parts (0.5 mol) of acryloyloxyethyl isocyanate to 30 parts.
It dripped over minutes. At this time, the reaction heat was generated, but the reaction temperature was kept at 50 to 60 ° C. Then, the temperature was maintained at 60 ° C. for 1 hour to complete the synthesis. 50% of unsaturated urethane A-1,
A monomer solution a-1 containing 50% of polyethylene glycol (molecular weight 200) diacrylate was obtained.

Unsaturated urethane A-2, A-3, R-
Synthesis of 1, R-2 and monomer solution a-2, a-3, r
Preparation of -1, r-2 In the same manner as in the synthesis of unsaturated urethane A-1 and the monomer solution a-1, synthesis of unsaturated urethane A-2 and the preparation of monomer solution a-2, unsaturated urethane A -3, preparation of monomer solution a-3, unsaturated urethane R-1
Was synthesized, a monomer solution r-1 was prepared, an unsaturated urethane R-2 was synthesized, and a monomer solution r-2 was prepared.

Synthesis of unsaturated urethane B-1 and preparation of monomer solution b-1 111 parts (0.5 mol) of isophorone diisocyanate,
100 parts of dry toluene and 0.5 part of di-n-butyltin dilaurate were placed in a reaction vessel, kept at 50 ° C. and stirred, and 58 parts (0.5 mol) of 2-hydroxyethyl acrylate was added dropwise over 30 minutes. did. During this period, the reaction temperature was kept at 50 to 60 ° C. After that, the reaction is continued at 50 to 55 ° C., and the residual amount of isocyanate groups in the reaction product is 1 of the theoretical amount calculated from the amount of diisocyanate used for the reaction.
The reaction was terminated when it became / 2. The reaction product obtained here is an unsaturated urethane monoisocyanate in which 1 mol of isophorone diisocyanate and 1 mol of 2-hydroxyethyl acrylate are bonded. Then add 6
The mixture was kept at 0 ° C. and stirred, and 143 parts (0.5 mol) of glycerin monomethacrylate monooctanoate obtained in Preliminary Synthesis Example 1 was added dropwise over 30 minutes. At this time, reaction heat was generated, but the reaction temperature was kept at 60 to 70 ° C. Then, the temperature was maintained at 70 ° C. for 2 hours to complete the synthesis. Furthermore, triethoxylated trimethylolpropane diacrylate
368 parts of monomethacrylate were added and dissolved, and toluene was distilled off under reduced pressure to obtain 50% unsaturated urethane B-1.
Monomer solution containing 50% triethoxylated trimethylolpropane diacrylate monomethacrylate b-
Got 1.

.Unsaturated urethane B-2, B-3, R-
3, R-4 synthesis and monomer solutions b-2, b-3, r
-3, r-4 Synthesis of unsaturated urethane B-2 and preparation of monomer solution b-2, unsaturated urethane B in the same manner as in the synthesis of unsaturated urethane B-1 and monomer solution b-1 -3, preparation of monomer solution b-3, unsaturated urethane R-3
Was prepared and the monomer solution r-3 was prepared, the unsaturated urethane R-4 was prepared, and the monomer solution r-4 was prepared.

[0036]

[Table 1]

In Table 1, numerical values in the upper row: parts Numerical values in parentheses in the lower row: mol * 1: polyethylene glycol (molecular weight 200) diacrylate * 2: triethoxylated trimethylolpropane diacrylate / monomethacrylate ** 1: glycerin Monomethacrylate monooctanoate (obtained in Preliminary Synthesis Example 1) ** 2: glycerin monoacrylate monolaurate (obtained in Preliminary Synthesis Example 2) ** 3: diglycerin diacrylate monooleate (preliminary (Obtained in Synthesis Example 3) ** 4: glycerin dimethacrylate ** 5: ε-caprolactone adduct of 2-hydroxyethyl acrylate (obtained in Preliminary Synthesis Example 4) ** 6: acryloyloxyethyl isocyanate ** 7: Methacryloyloxyethyl isocyanate ** 8: Isophorone diisocyanate Sulfonate / 2-hydroxyethyl acrylate = 1/1 (molar ratio) reaction product ** 9: isophorone diisocyanate / 2-hydroxyethyl methacrylate = 1/1 (molar ratio) reaction product

[0038]

[Table 2]

In Table 2, A: acryloyl group M: methacryloyl group

Test Category 3 (Examples and Comparative Examples and Their Evaluation) Examples 1 to 12 and Comparative Examples 1 to 6 Photopolymerizability using the monomer solutions shown in Table 1 and having the compositions shown in Table 3 or Table 4. A composition was prepared. Then, using a three-dimensional NC table equipped with a container filled with the photopolymerizable composition and an optical three-dimensional modeling apparatus mainly composed of a helium / cadmium laser light (wavelength 3250 angstrom) control system, By irradiating a helium / cadmium laser beam focused from the direction perpendicular to the surface, a disk having a diameter of 150 mm and a thickness of 10 mm was formed. The time required for modeling was measured for each photopolymerizable composition. The shaped disc was cut into a test piece having a length of 127 mm and a width of 12.7 mm using a diamond cutter. The molding shrinkage and the heat distortion temperature of this test piece were measured by the following methods. The results are shown in Table 3 or Table 4.

Modeling shrinkage: The density (D ₁ ) of the test piece and the density (D ₂ ) of the photopolymerizable composition used for modeling were measured, and the modeling shrinkage was calculated by the following formula. Modeling shrinkage rate (%) = {(1 / D ₂ ) − (1 / D ₁ )} × 1
00 Heat distortion temperature: Measured according to JIS-K6919.

[0042]

[Table 3]

[0043]

[Table 4]

In Tables 3 and 4, * 3: 1-hydroxycyclohexyl phenyl ketone (trade name: Irgacure 184, manufactured by Ciba Geigy) * 4: Silica fume with an average particle diameter of 0.1 μm * 5: Average fiber length of 10 μm Magnesium sulfate fiber whiskers of Comparative Example 1: Significant cracks and warpage occurred on the shaped disc Comparative Example 3: Cracks occurred on the shaped disc

[0045]

As is apparent from the above, according to the present invention described above, improvement of photopolymerization reactivity, reduction of reaction shrinkage in the photopolymerization reaction, and improvement of thermal physical properties of the obtained cured molded article can be simultaneously achieved. There is an effect.

Claims (3)

[Claims] 1. An unsaturated urethane represented by the following formula 1 and
And 1 selected from unsaturated urethanes represented by the following formula 2
Type or two or more types of unsaturated urethane and the unsaturated urethane
Photopolymerization with (meth) acrylic acid ester copolymerizable with
Consisting of an initiator and the unsaturated urethane / the (meth)
Acrylic ester = 10/90 to 90/10 (weight
Ratio) ratio for optical three-dimensional modeling
Photopolymerizable composition. [Formula 1][Formula 2][In Formula 1 and Formula 2, X¹, X²: Removed hydroxyl groups from tri- or tetravalent polyols
Residue Y: residue obtained by removing isocyanate group from diisocyanate
Group R¹, R^Four: H or CH that are not the same at the same time₃  R², R⁶: C5 to C21 aliphatic hydrocarbon group R³: C2-C4 alkylene group R^Five, R⁸: H or CH that are not the same at the same time₃ R⁷: Of an alkylene group having 2 to 6 carbon atoms or an alkylene group
A polyalkylene glycol residue having 2 or 3 carbon atoms, p, q, r: 1 or 2, and p + q + r = 3 or
Satisfying 4 s, t, u: 1 or 2, and s + t + u = 3 or
Satisfying 4] 2. The photopolymerizable composition for optical stereolithography according to claim 1, wherein the (meth) acrylic acid ester is a mixed unsaturated acid ester obtained from a polyol, acrylic acid and methacrylic acid. 3. Solid fine particles having an average particle diameter of 0.1 to 50 μm and an average fiber length of 1 to 70 per 100 parts by weight of the total amount of unsaturated urethane and (meth) acrylic acid ester.
The photopolymerizable composition for optical three-dimensional modeling according to claim 1 or 2, containing one or more fillers selected from inorganic fiber whiskers having a diameter of 300 μm in a proportion of 300 parts by weight or less.