JP2017039797A - Resin composition for optical three-dimensional molding, and method for producing three-dimensional molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel composition for optical three-dimensional molding that can form a three-dimensional molding having characteristics such as shape memory.SOLUTION: A composition for optical three-dimensional molding comprises a reactive monomer comprising a radical-polymerizable compound represented by formula (I), where X, Rand Rindependently represent a divalent organic group, Rand Rindependently represent a hydrogen atom or a methyl group, a linear or branched polymer, and a photoinitiator.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition for optical three-dimensional modeling, and a method for producing a three-dimensional molded item.

  In recent years, a technique for three-dimensional modeling using a resin has been developed based on three-dimensional data such as 3D CAD. Among these, when a photocurable resin is used, a shaped article having a complicated shape can be obtained in a relatively short time, and a large-scale apparatus is not required. Therefore, application in a wide range of fields is expected. As a method of optical three-dimensional modeling, for example, the liquid raw material in the container is irradiated with light to form a planar shaped object as the first layer, and then a new raw material is supplied in the vertical direction. A method of sequentially forming the second and subsequent layers is known. Conventionally, various photocurable resin compositions for optical three-dimensional modeling have been developed (for example, Patent Documents 1 to 3).

JP 09-169827 A JP 2005-015739 A JP 2006-028499 A

  The present invention provides a novel resin composition for optical three-dimensional modeling that can form a three-dimensional modeled product having characteristics such as shape memory.

で表され、Ｘ、Ｒ^１及びＲ^２がそれぞれ独立に２価の有機基で、Ｒ^３及びＲ^４がそれぞれ独立に水素原子又はメチル基である、ラジカル重合性化合物を含む反応性モノマーと、直鎖状又は分岐状の重合体と、光重合開始剤と、を含有する、光学的立体造形用樹脂組成物に関する。 One aspect of the present invention is a compound of formula (I):

A reactive monomer containing a radical polymerizable compound, wherein X, R ¹ and R ² are each independently a divalent organic group, and R ³ and R ⁴ are each independently a hydrogen atom or a methyl group; The present invention relates to a resin composition for optical three-dimensional modeling, which contains a linear or branched polymer and a photopolymerization initiator.

  In another aspect of the present invention, in the optical three-dimensional modeling resin composition, a first polymer containing a reactive monomer as a monomer unit is generated by photoradical polymerization of a reactive monomer, The present invention relates to a method for producing a three-dimensional model, comprising a step of forming a molded body layer including a polymer and a linear or branched polymer as a second polymer. The process of forming a molded body layer is repeated twice or more, thereby forming a three-dimensional model including a plurality of molded body layers.

  According to one aspect of the present invention, it is possible to obtain an optical three-dimensional modeled object having shape memory properties excellent in shape recovery by heating.

  According to optical three-dimensional modeling, a modeled object can be manufactured with high accuracy. According to some disclosed resin compositions, it is possible to form a three-dimensional model that is more tough and hard to break, adapted to a complicated fine shape. In addition, the three-dimensional model formed can have good flexibility and scratch resistance. Having good flexibility and scratch resistance is strongly desired in the opportunity to come into contact with humans or to be used in harsh conditions, such as a general household.

It is a schematic diagram which shows the member containing the metal mold | die for manufacturing a three-dimensional molded item. It is the II-II sectional view taken on the line of the metal mold | die of FIG. It is the II-II sectional view taken on the line of the metal mold | die of FIG. It is sectional drawing which shows one Embodiment of a three-dimensional molded item.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

  The resin composition which concerns on one Embodiment is used in order to manufacture a three-dimensional molded item by optical three-dimensional modeling. This resin composition contains a reactive monomer, a linear or branched polymer (second polymer), and a photopolymerization initiator.

で表されるラジカル重合性化合物を含む。式（Ｉ）中、Ｘ、Ｒ^１及びＲ^２がそれぞれ独立に２価の有機基で、Ｒ^３及びＲ^４がそれぞれ独立に水素原子又はメチル基である。樹脂組成物中で反応性モノマーが重合することで、反応性モノマーに由来するモノマー単位から構成される第一の重合体が生成する。これにより、樹脂組成物が硬化して、立体造形物を構成する樹脂成形体（硬化体）が形成される。第一の重合体は、通常、第二の重合体と共有結合によって結合することなく、第二の重合体とは別の重合体として成形体中に形成される。 The reactive monomer is represented by the formula (I):

The radically polymerizable compound represented by these is included. In formula (I), X, R ¹ and R ² are each independently a divalent organic group, and R ³ and R ⁴ are each independently a hydrogen atom or a methyl group. As the reactive monomer is polymerized in the resin composition, a first polymer composed of monomer units derived from the reactive monomer is generated. Thereby, a resin composition hardens | cures and the resin molding (hardened body) which comprises a three-dimensional molded item is formed. The first polymer is usually formed in the molded body as a polymer different from the second polymer without being covalently bonded to the second polymer.

  The first polymer may include a cyclic monomer unit represented by the following formula (II) derived from the compound of the formula (I). It is considered that the cyclic monomer unit of the formula (II) contributes to the expression of unique characteristics such as the shape memory property of the resin molded body. However, the first polymer does not necessarily contain the monomer unit of the formula (II).

で表される基であってもよい。式（１０）中、Ｙは置換基を有していてもよい環状基で、Ｚ^１及びＺ^２はそれぞれ独立に炭素原子、酸素原子、窒素原子、及び硫黄原子から選ばれる原子を含む官能基で、ｉ及びｊはそれぞれ独立に０〜２の整数である。＊は結合手を表す（これは他の式でも同様である）。Ｘが式（１０）の基であると、式（ＩＩ）の環状のモノマー単位が特に形成され易いと考えられる。環状基Ｙに対するＺ^１及びＺ^２の配置が、シス位であってもよいし、トランス位であってもよい。Ｚ^１及びＺ^２は、−Ｏ−、−ＯＣ（＝Ｏ）−、−Ｓ−、−ＳＣ（＝Ｏ）−、−ＯＣ（＝Ｓ）−、−ＮＲ^１０−（Ｒ^１０は水素原子又はアルキル基）、又は−ＯＮＨ−で表される基であってもよい。 X in the formulas (I) and (II) is, for example, the following formula (10):

The group represented by these may be sufficient. In formula (10), Y is a cyclic group which may have a substituent, and Z ¹ and Z ² are each independently a functional group containing an atom selected from a carbon atom, an oxygen atom, a nitrogen atom and a sulfur atom. And i and j are each independently an integer of 0 to 2. * Represents a bond (this also applies to other formulas). When X is a group of the formula (10), it is considered that the cyclic monomer unit of the formula (II) is particularly easily formed. The arrangement of Z ¹ and Z ^{2 with} respect to the cyclic group Y may be a cis position or a trans position. Z ¹ and Z ² are —O—, —OC (═O) —, —S—, —SC (═O) —, —OC (═S) —, —NR ¹⁰ — (R ¹⁰ is a hydrogen atom or An alkyl group) or a group represented by -ONH-.

  Y may be a cyclic group having 2 to 10 carbon atoms, and may contain a hetero atom selected from an oxygen atom, a nitrogen atom and a sulfur atom. The cyclic group Y is, for example, an alicyclic group, a cyclic ether group, a cyclic amine group, a cyclic thioether group, a cyclic ester group, a cyclic amide group, a cyclic thioester group, an aromatic hydrocarbon group, a heteroaromatic hydrocarbon group, or It can be a combination of these. The cyclic ether group may be a cyclic group possessed by a monosaccharide or polysaccharide. Specific examples of Y include, but are not particularly limited to, a cyclic group represented by the following formula (11), (12), (13), (14) or (15). From the viewpoint of stress relaxation properties of the resulting three-dimensional structure, Y may be a group of formula (11) (particularly a 1,2-cyclohexanediyl group).

で表される基であってもよい。 X in the formula (I) is the following formula (10): Y is a 1,2-cyclohexanediyl group, Z ¹ and Z ² are groups represented by —O—, i and j are 0, Formula (40):

The group represented by these may be sufficient.

R ¹ and R ² in the formulas (I) and (II) may be the same as or different from each other, and may be a group represented by the following formula (20).

In the formula (20), R ⁶ is a hydrocarbon group having 1 to 8 carbon atoms (an alkylene group or the like), and is bonded to the nitrogen atom in the formula (I) or (II). Z ³ is a group represented by —O— or —NR ¹⁰ — (R ¹⁰ is a hydrogen atom or an alkyl group). When R ¹ and R ² are a group of the formula (20), it is considered that the cyclic monomer unit of the formula (II) is particularly easily formed. The number of carbon atoms in R ⁶ may be 2 or more, 6 or less, or 4 or less.

One specific example of the radically polymerizable compound of the formula (I) is a compound represented by the following formula (Ia). Here, Y, Z ¹ , Z ² , i, and j are defined in the same manner as in Expression (10).

  Examples of the compound of the formula (Ia) include the following formulas (I-1), (I-2), (I-3), (I-4), (I-5), (I-6), ( Examples thereof include compounds represented by I-7) or (I-8).

  The compounds exemplified above can be used alone or in combination of two or more.

  The proportion of the radically polymerizable compound of formula (I) in the resin composition was 0.01 mol% or more, 0.1 mol% or more, or 0.5 mol% or more based on the total amount of reactive monomers. It may be 10 mol% or less, 5 mol% or less, or 1 mol% or less. Alternatively, the proportion of the radically polymerizable compound of formula (I) in the resin composition is 0.01% by mass or more, 0.1% by mass or more, or 0.5% by mass or more based on the total mass of the reactive monomer. It may be 25 mass% or less, 15 mass% or less, or 5 mass% or less. When the ratio of the radically polymerizable compound of the formula (I) is within these ranges, a more advantageous effect can be obtained in that a three-dimensional molded article having excellent mechanical properties such as elongation and strength can be obtained.

  As understood by those skilled in the art, the compound of the formula (I) can be synthesized by a usual synthesis method using a commonly available starting material as a starting material. For example, the compound of formula (I) can be synthesized by reacting a cyclic diol compound or a cyclic diamine compound with a compound having a (meth) acryloyl group and an isocyanate group.

  The reactive monomer in the resin composition may further contain a monofunctional radically polymerizable monomer. The monofunctional radically polymerizable monomer may contain, for example, alkyl (meth) acrylate and / or acrylonitrile.

  The alkyl (meth) acrylate may have a substituent, and the alkyl (meth) acrylate having a C 1-16 alkyl group ((meth) acrylic acid and optionally having 1 substituent) To 16 alkyl alcohols). The substituent that the alkyl (meth) acrylate having an alkyl group having 1 to 16 carbon atoms may have an oxygen atom and / or a nitrogen atom.

  When the reactive monomer contains an alkyl (meth) acrylate having an alkyl group having 1 to 16 carbon atoms, an effect that the elastic modulus and glass transition temperature (Tg) of the resin molded body can be controlled is obtained.

  The proportion of the alkyl (meth) acrylate having 1 to 16 carbon atoms that may have a substituent in the resin composition is 10 mol% or more, 15 mol% or more, or based on the total amount of the reactive monomer, or It may be 20 mol% or more, 95 mol% or less, 90 mol% or less, or 85 mol% or less. Or the ratio of the C1-C16 alkyl (meth) acrylate which may have a substituent is 5 mass% or more, 10 mass% or more, or 15 mass% on the basis of the whole quantity of a reactive monomer. The above may be sufficient, and 95 mass% or less, 90 mass% or less, or 85 mass% or less may be sufficient. If the proportion of the alkyl (meth) acrylate having 1 to 16 carbon atoms that may have a substituent is within these ranges, a three-dimensional molded article having excellent mechanical properties such as elongation and strength can be obtained. An advantageous effect is obtained.

  By using an alkyl (meth) acrylate having an alkyl group having a small number of carbon atoms, the elastic modulus of the three-dimensional structure after curing tends to be high, and shape memory properties tend to be easily exhibited. From such a viewpoint, the reactive monomer may contain an alkyl (meth) acrylate having an alkyl group having 10 or less carbon atoms, which may have a substituent, as a monofunctional radical polymerizable monomer. The proportion of the alkyl (meth) acrylate having 10 or less carbon atoms that may have a substituent in the resin composition is 8 mol% or more, 10 mol% or more, or 15 based on the total amount of the reactive monomer. It may be at least mol%, may be at most 55 mol%, at most 45 mol%, or at most 25 mol%. Alternatively, the proportion of the alkyl (meth) acrylate having 10 or less carbon atoms which may have a substituent is 3% by mass or more, 5% by mass or more, or 10% by mass or more based on the total amount of the reactive monomer. It may be 85 mass% or less, 75 mass% or less, or 60 mass% or less. When the ratio of the alkyl (meth) acrylate having an alkyl group having 10 or less carbon atoms which may have a substituent is within these ranges, a three-dimensional modeled object having a certain degree of elastic modulus and shape memory property is obtained. A further advantageous effect is obtained in that it is easily formed. From the same viewpoint, the reactive monomer may contain a (meth) acrylate having an alkyl group having 8 or less carbon atoms which may have a substituent, and the ratio thereof may be in the above numerical range. .

  Examples of the alkyl (meth) acrylate having 1 to 16 carbon atoms which may have a substituent include ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, hexyl acrylate, Hexyl methacrylate, 2-ethylhexyl acrylate (EHA), 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxy-1-methylethyl methacrylate, 2-methoxyethyl acrylate (MEA), N, N -Dimethylaminoethyl acrylate and glycidyl methacrylate. These can be used alone or in combination of two or more.

  When the reactive monomer contains acrylonitrile, there is a tendency that a three-dimensionally shaped object having a certain degree of elasticity and shape memory is easily formed. A combination of acrylonitrile and a (meth) acrylate having an alkyl group having 1 to 16 (or 1 to 10) carbon atoms is particularly advantageous in order to obtain a three-dimensionally shaped article having a high elastic modulus. The proportion of acrylonitrile in the resin composition may be 40 mol% or more, 50 mol% or more, or 70 mol% or more based on the total amount of the reactive monomer, and is 90 mol% or less, 85 mol% or less. Or 80 mol% or less. Alternatively, the proportion of acrylonitrile may be 10% by mass, 15% by mass, or 30% by mass based on the total amount of reactive monomer, based on the total amount of reactive monomer, and 80% by mass. % Or less, 70 mass% or less, or 60 mass% or less may be sufficient. When the ratio of acrylonitrile is within these ranges, a further advantageous effect can be obtained in that the shape recovery is quick.

  The reactive monomer may contain 1 type, or 2 or more types of compounds chosen from vinyl ether, styrene, and a styrene derivative as a monofunctional radically polymerizable monomer. Examples of vinyl ethers include vinyl butyl ether, vinyl octyl ether, vinyl-2-chloroethyl ether, vinyl isobutyl ether, vinyl dodecyl ether, vinyl kutadecyl ether, vinyl phenyl ether, and vinyl cresyl ether. Examples of styrene derivatives include alkyl styrene, alkoxy styrene (α-methoxy styrene, p-methoxy styrene, etc.), and m-chlorostyrene.

  The reactive monomer may contain other monofunctional radically polymerizable monomers. Examples of other monofunctional radically polymerizable monomers include vinyl phenol, N-vinyl carbazole, 2-vinyl-5-ethyl pyridine, isopropenyl acetate, vinyl isocyanate, vinyl isobutyl sulfide, 2-chloro-3-hydroxypropene, Vinyl stearate, p-vinylbenzylethyl carbinol, vinyl phenyl sulfide, allyl acrylate, α-chloroethyl acrylate, allyl acetate, 2,2,6,6-tetramethyl-piperidinyl methacrylate, N, N-diethyl vinyl Carbamate, vinyl isopropenyl ketone, N-vinyl caprolactone, vinyl formate, p-vinyl benzylmethyl carbinol, vinyl ethyl sulfide, vinyl ferrocene, vinyl dichloroacetate, N-vinyl succin Bromide, allyl alcohol, norbornadiene, diallyl melamine, vinyl chloroacetate, N- vinylpyrrolidone, vinyl methyl Sufi de, N- vinyl oxazolidone, vinyl methyl sulfoxide, N- vinyl -N'- ethylurea, and include acenaphthalene.

  The various reactive monomers exemplified above can be used alone or in combination of two or more.

The resin composition contains the reactive monomer described above and a linear or branched polymer (second polymer). The second polymer may be a polymer including two or more linear chains and a linking group that connects the ends thereof. This polymer includes a molecular chain represented by the following formula (B), for example. In Formula (B), R ²⁰ is a monomer unit constituting a linear chain, n ¹ , n ² and n ³ are each independently an integer of 1 or more, and L is a linking group. A plurality of R ²⁰ and L in the same molecule may be the same or different.

Linear chain composed of monomer units R ²⁰ are polyether, polyester, polyolefin, polyorganosiloxane, or a molecular chain derived from these combinations. Each linear chain may be a polymer or an oligomer.

  Examples of linear chains derived from polyethers include polyoxyalkylene chains such as polyoxyethylene chains, polyoxypropylene chains, polyoxybutylene chains, and combinations thereof. Polyoxyethylene chains are derived from polyethers such as polyalkylene glycols. Examples of linear chains derived from polyolefins include polyethylene chains, polypropylene chains, polyisobutylene chains, and combinations thereof. Examples of linear chains derived from polyester include poly ε-caprolactone chains. Examples of the linear chain derived from polyorganosiloxane include a polydimethylsiloxane chain. The polymer can contain these alone or in a combination of two or more selected from these.

  The number average molecular weight of each of the linear molecular chains constituting the second polymer is not particularly limited, but may be, for example, 1000 or more, 3000 or more, or 5000 or more, and may be 80000 or less, 50000 or less, or 20000. It may be the following. In the present specification, the number average molecular weight means a standard polystyrene equivalent value obtained by gel permeation chromatography unless otherwise defined.

  The linking group L is an organic group containing a cyclic group or a branched organic group. The linking group L may be, for example, a divalent group represented by the following formula (30).

R ³⁰ is a cyclic group, a group containing two or more cyclic groups, which are bonded directly or via an alkylene group, or a carbon atom, and is selected from an oxygen atom, a nitrogen atom, a sulfur atom and a silicon atom The branched organic group which may contain the hetero atom is shown. Z ⁵ and Z ⁶ are divalent groups that bind R ³⁰ and a linear chain. For example, —NHC (═O) —, —NHC (═O) O—, —O—, —OC ( ═O) —, —S—, —SC (═O) —, —OC (═S) —, or —NR ¹⁰ — (R ¹⁰ is a hydrogen atom or an alkyl group). In the present specification, the atom at the end of the linear chain (the atom derived from the monomer constituting the linear chain) is not normally interpreted as an atom constituting Z ⁵ or Z ⁶ . If it is not clear whether the atom at the end of the linear chain is an atom derived from a monomer, the atom may be interpreted as being included in either the linear chain or the linking group.

  The cyclic group contained in the linking group L may contain a hetero atom selected from a nitrogen atom and a sulfur atom. The cyclic group included in the linking group L is, for example, an alicyclic group, a cyclic ether group, a cyclic amine group, a cyclic thioether group, a cyclic ester group, a cyclic amide group, a cyclic thioester group, an aromatic hydrocarbon group, or a heteroaromatic hydrocarbon. It can be a group or a combination thereof. Specific examples of the cyclic group contained in the linking group L include 1,4-cyclohexanediyl group, 1,2-cyclohexanediyl group, 1,3-cyclohexanediyl group, 1,4-benzenediyl group, 1,3-benzene. Examples include a diyl group, a 1,2-benzenediyl group, and a 3,4-furandiyl group.

Examples of the branched organic group (for example, R ³⁰ in the formula (30)) included in the linking group L include a lysine triyl group, a methylsilanetriyl group, and a 1,3,5-cyclohexanetriyl group.

The linking group L represented by the formula (30) may be a group represented by the following formula (31). R ³¹ in the formula (31) represents a single bond or an alkylene group. R ³¹ may be an alkylene group having 1 to 3 carbon atoms. Defining Z ⁵ and ^{Z 6} are the same as equation (30).

  The weight average molecular weight of the second polymer is not particularly limited, but may be, for example, 5000 or more, 7000 or more, or 9000 or more, or 100000 or less, 80000 or less, or 60000 or less. In this specification, the weight average molecular weight means a standard polystyrene equivalent value determined by gel permeation chromatography unless otherwise defined. When the weight average molecular weight of the polymer is within these numerical ranges, good compatibility with other components of the polymer and good various properties of the three-dimensional model tends to be obtained.

  As will be understood by those skilled in the art, the second polymer can be obtained by a usual synthesis method using a commonly available raw material as a starting material. For example, a polyalkylene glycol having a reactive end group (such as a hydroxyl group), a polyester, a polyolefin, a polyorganosiloxane, or a mixture containing a combination thereof, a reactive functional group (such as an isocyanate group), and a cyclic or branched group A polymer can be synthesized by a reaction with a compound having the above group. The synthesized polymer may contain a branched structure based on side reactions such as trimerization of isocyanate groups.

  There is no restriction | limiting in particular as a photoinitiator, The photoinitiator used normally can be used. Examples of photopolymerization initiators include benzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2- Aromatic ketones such as morpholino-propanone-1,2,2-dimethoxy-1,2-diphenylethan-1-one (Irgacure 651 (manufactured by Ciba Geigy Japan)); quinone compounds such as alkylanthraquinones; benzoin alkyl ethers and the like Benzoin compounds such as benzoin and alkylbenzoin; benzyl derivatives such as benzyldimethyl ketal; 2- (2-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (2-fluorophenyl) -4 2,4 such as 1,5-diphenylimidazole dimer 5-triaryl imidazole dimer; 9-phenyl acridine, 1,7 (9,9'-acridinyl) include acridine derivatives such as heptane. These can be used alone or in combination of two or more.

  The resin composition may contain a solvent or may be substantially solvent-free. The resin composition may be liquid, semi-solid, or solid. The resin composition before curing may be in the form of a film.

  Resin compositions include binder polymers, photochromic agents, thermochromic inhibitors, plasticizers, pigments, fillers, antifoaming agents, flame retardants, stabilizers, adhesion-imparting agents, leveling agents, and release accelerators as necessary. Agents, antioxidants, fragrances, imaging agents, thermal crosslinking agents, and the like. These can be used alone or in combination of two or more. When the resin composition contains other components, the content thereof may be 10% by mass or less based on the total mass of the resin composition.

Method of manufacturing a three-dimensional modeled object A three-dimensional modeled object is a resin composition according to the above-described embodiment, for example, by generating a first polymer by photo radical polymerization of a reactive monomer, and the first polymer and It can manufacture by the method provided with the process of forming the molded object layer containing a 2nd polymer. The process of forming a molded body layer is repeated twice or more, thereby forming a three-dimensional model including a plurality of molded body layers.

  1-3 show one Embodiment of the method of manufacturing a three-dimensional molded item, FIG. 4 shows one Embodiment of a three-dimensional molded item. FIG. 1 is a schematic diagram showing a member including a mold for manufacturing a three-dimensional model. 2 and 3 are cross-sectional views taken along the line II-II in FIG.

  As shown in FIG. 1, the base 2, the release film 4, the mold frame 6, the transparent sheet 8, and the mask 10 are stacked in this order. As shown in FIG. The resin composition 12 is filled into the mold frame 6 having a height h. In this state, an actinic ray is irradiated from the mask 10 side, and the resin composition 12 in a portion not covered with the mask 10 is exposed to be cured. By removing the uncured portion of the resin composition 12, a first molded product layer 12a having a predetermined pattern shown in FIG. 3 is formed.

  Subsequently, as shown in FIG. 3, instead of the mold frame 6 of FIG. 1, a mold frame 6a having a height H larger than this is used, and the resin composition 14 is filled into the mold frame 6a. . In this state, actinic rays are irradiated from the mask 10 side, and the resin composition 14 in a portion not covered with the mask 10 is exposed to be cured. By removing the uncured portion of the resin composition 14, a second molding layer 14a shown in FIG. 4 is formed. Thereby, the three-dimensional molded item 40 which has the 1st molded article layer 12a and the 2nd molded article layer 14a, and these were laminated | stacked is obtained. It is desirable that the plurality of molded product layers are integrated so that their boundaries cannot be visually confirmed.

  The active light for the polymerization of reactive monomers is typically ultraviolet light. This polymerization (or curing) is preferably performed in an atmosphere of an inert gas such as nitrogen gas, helium gas, or argon gas. Thereby, the polymerization inhibition by oxygen is suppressed and a three-dimensional molded article of good quality can be obtained stably. The method for removing the uncured portion of the resin composition is not particularly limited, and may be a method usually employed in the field of optical three-dimensional modeling, such as a method using a solvent.

  Needless to say, the three-dimensional structure is not limited to the form shown in FIG. The shape, size, and number of molded product layers of the three-dimensional model are not particularly limited and are arbitrary.

It is believed that when a reactive monomer containing a radically polymerizable compound of formula (I) is polymerized, a cyclic monomer unit of formula (II) is formed. When the reactive monomer is polymerized in the presence of the first polymer, a structure in which the second polymer passes through the cyclic portion may be formed in at least a part of the cyclic monomer unit of the formula (II). The following formula (III) schematically shows a structure in which the second polymer (B) penetrates the cyclic portion of the monomer unit of the formula (II) of the first polymer (A). R ⁵ in the formula (III) is a monomer unit derived from a reactive monomer other than the radical polymerizable compound of the formula (I). By forming a structure like Formula (III), a crosslinked network structure like a three-dimensional copolymer is formed by the first polymer and the second polymer. In this network structure, it is considered that the degree of freedom of movement of the second polymer penetrating the annular portion is kept relatively high. Such a structure may be referred to as a ring structure by those skilled in the art, and the present inventors speculate that this contributes to the expression of unique characteristics such as shape memory properties of a three-dimensional structure. Yes. Although it is not technically easy to directly confirm that a ring structure is formed, for example, a stress-strain curve obtained by a tensile test of a three-dimensional structure is a so-called J-shaped curve. This suggests the formation of a ring structure. However, the three-dimensional structure does not necessarily include such a ring structure.

  In the example of the formula (III), the second polymer (B) has a plurality of polyoxyethylene chains and a linking group L that connects the ends thereof. Since the linking group L is bulky compared to the polyoxyethylene chain, it is easy to maintain a state in which the second polymer penetrates the cyclic portion of the monomer unit of the formula (II) as in the polyrotaxane. The second polymer can be appropriately selected based on the balance of the size of the cyclic monomer unit, the inclusion ability, and the properties of the polyrotaxane.

  The three-dimensional model formed and cured by the first polymer may or may not have shape memory, but by selecting the type of the reactive monomer appropriately, the shape memory It is possible to obtain a three-dimensionally shaped object having properties. In this specification, “shape memory property” means that when a three-dimensional structure is deformed by an external force at room temperature (for example, 25 ° C.), the three-dimensional structure retains the deformed shape at room temperature, It means the property of returning to its original shape when heated to a high temperature. However, the three-dimensional modeled object does not need to completely recover the same shape as the original shape by heating. The heating temperature for shape recovery is 70 ° C., for example.

  When the cured three-dimensional model has shape memory, the shape of the three-dimensional model at the time when the first polymer is generated and cured is the basic shape. The three-dimensional structure deformed by the external force is deformed so as to approach this basic shape by heating. By solidifying the three-dimensional object in a mold having a predetermined shape, a three-dimensional object having a desired shape as a basic shape can be obtained.

  Although the tensile elasticity modulus in 25 degreeC of a three-dimensional molded item is not specifically limited, 0.5 Mpa or more may be sufficient. A three-dimensionally shaped object having a tensile modulus of 0.5 MPa or more usually has shape memory. The elastic modulus of the three-dimensional structure may be 1 MPa or more, or 10 MPa or more, or 10 GPa or less, 5 GPa or less, or 500 MPa or less. Since the tensile elastic modulus is high, there is a tendency that the three-dimensional structure easily maintains the shape after deformation. By having an appropriate tensile modulus, the three-dimensional object tends to recover its original shape when heated. The elastic modulus of the three-dimensional structure can be controlled based on, for example, the type of reactive monomer and the blending ratio thereof, the molecular weight of the second polymer, and the amount of radical polymerization initiator.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples.

1. Synthesis Synthesis Example 1. Synthesis of trans-1,2-bis (2-acryloyloxyethylcarbamoyloxy) cyclohexane (BACH) Trans-1,2-cyclohexanediol (2.32 g, 20.0 mmol) was added to a 100 mL two-necked eggplant flask, Was replaced with nitrogen. Thereto was added dichloromethane (40 mL) and dibutyltin dilaurate (11.8 μL, 0.10 mol%: 0.020 mmol). To the reaction solution in the flask, a solution of 2-acryloyloxyethyl isocyanate (5.93 g, 42.0 mmol) in dichloromethane (4 mL) was added dropwise from a dropping funnel, and the reaction solution was stirred at 30 ° C. for 24 hours to allow the reaction to proceed. It was. After completion of the reaction, diethyl ether was added to the reaction solution and washed with saturated brine. After drying the organic layer over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure, and a solution containing the desired product was isolated from the residue by silica gel chromatography (developing solvent; chloroform), and concentrated. The obtained crude product was purified by recrystallization from diethyl ether and hexane to obtain white crystals of BACH. The yield was 3.78 g, and the yield was 47.4% by mass.

Synthesis Example 2: Synthesis of PEG-PPG oligomer Polyethylene glycol (PEG 1500, 750 mg, 0.500 mmol, number average molecular weight 1500) and polypropylene glycol (PPG 4000, 2000 mg, 0.500 mmol, number average molecular weight 4000) were added to a 20 mL eggplant flask. Then, the flask was purged with nitrogen, and the contents were melted at 115 ° C. 4,4′-dicyclohexylmethane diisocyanate (262 mg, 1.00 mmol) was added to the melt, and the melt was stirred at 115 ° C. for 24 hours under a nitrogen atmosphere to obtain a PEG-PPG oligomer (polyoxyethylene chain and polyoxyethylene chain). A polymer containing an oxypropylene chain) was obtained.
GPC chromatograms of oligomers were obtained using DMF (N, N-dimethylformamide) containing 10 mM lithium bromide as an eluent at a flow rate of 1 mL / min. From the obtained chromatogram, the number average molecular weight and the weight average molecular weight of the oligomer were determined as polystyrene conversion values. The weight average molecular weight (Mw) of the oligomer was 9300, and the weight average molecular weight / number average molecular weight (Mw / Mn) of the oligomer was 1.65.

3. Optical three-dimensional modeling resin composition Example 1
BACH of Synthesis Example 1, PEG-PPG oligomer of Synthesis Example 2, acrylonitrile, 2-ethylhexyl acrylate and Irgacure 651 are added to a sample bottle at a mass ratio shown in Table 1 and dissolved by heating to obtain a resin composition of Example 1. It was.

Comparative Examples 1 and 2
Resin compositions of Comparative Examples 1 and 2 were obtained in the same manner as in Example 1 except that the mass ratio shown in Table 1 was changed.

Formability evaluation By the method shown in FIGS. 1-3, the three-dimensional molded item of the form shown in FIG. 4 was produced. As the release film 4 and the transparent sheet 8, a polyethylene terephthalate film was used. The resin composition was cured by irradiating the mask 10 with 2000 mJ / cm ² of ultraviolet rays. A stainless steel mold having a length x width x depth of 46 mm x 10 mm x 1 mm was used as a mold frame for forming the first molded product layer. As a mold frame for forming the second molding layer, a stainless mold frame having a length x width x depth of 46 mm x 10 mm x 1.5 mm was used. The obtained shaped article was visually observed, and the case where the boundary between the first layer and the second layer could not be confirmed was judged as “good”, and the case where it was confirmed was judged as “bad” to evaluate the formability.

Measurement of Breaking Strength, Breaking Elongation and Tensile Elastic Modulus The resin composition was poured into a stainless steel mold having a length x width x depth of 46 mm x 10 mm x 1 mm with a polyethylene terephthalate (PET) film laid on it, and made of PET there The transparent sheet was covered. A 2000 mJ / cm ² ultraviolet ray was irradiated from above the transparent sheet at room temperature (25 ° C., the same applies hereinafter) to obtain a resin film.
A strip-shaped test piece (width: 8 mm, thickness: 1 mm) was cut out from the obtained resin film. Using this test piece, the rupture strength, the rupture elongation, and the tensile elastic modulus were measured under the conditions of room temperature, distance between chucks: 30 mm, and tensile speed: 10.0 mm / min using Strograph T (manufactured by Toyo Seiki Seisakusho Co., Ltd.). It was measured.

Shape memory property The film was folded twice, and the crease was pressed with a glass tube in that state. Thereafter, the deformed film was immersed in water at 70 ° C., and it was visually confirmed that it returned to the initial shape within 10 seconds immediately after the immersion. The case where the film recovered the initial shape was determined as “good”, and the case where the film did not recover was determined as “bad”.

  According to the resin composition of Example 1, it was possible to form a three-dimensionally shaped article having good shapeability and shape memory.

  DESCRIPTION OF SYMBOLS 2 ... Base, 4 ... Release film, 6, 6a ... Mold frame, 8 ... Transparent sheet, 10 ... Mask, 12, 14 ... Resin composition, 12a ... 1st molding layer, 14a ... 2nd Molded product layer of layer 40, three-dimensional model.

Claims (6)

Formula (I):

A reactive monomer containing a radical polymerizable compound, wherein X, R ¹ and R ² are each independently a divalent organic group, and R ³ and R ⁴ are each independently a hydrogen atom or a methyl group;
A linear or branched polymer;
A photopolymerization initiator;
A resin composition for optical three-dimensional modeling.   The resin composition for optical three-dimensional model | molding of Claim 1 whose said polymer is a polymer containing a polyoxyalkylene chain. X in the formula (I) is the following formula (10):

Y is a cyclic group which may have a substituent, and Z ¹ and Z ² are each independently a functional group containing an atom selected from a carbon atom, an oxygen atom, a nitrogen atom and a sulfur atom, i The resin composition for optical three-dimensional modeling according to claim 1, wherein j is an integer of 0 to 2 and * is a group that represents a bond.   The resin composition for optical three-dimensional model | molding as described in any one of Claims 1-3 whose weight average molecular weights of the said polymer are 5000 or more.   The resin composition for optical three-dimensional model | molding as described in any one of Claims 1-4 in which the said reactive monomer further contains a monofunctional radically polymerizable monomer. In the resin composition for optical three-dimensional model | molding as described in any one of Claims 1-5, the 1st polymer which contains the said reactive monomer as a monomer unit by photoradical polymerization of the said reactive monomer is produced | generated. And forming a molded body layer containing the first polymer and the linear or branched polymer as the second polymer,
By repeating the step of forming the molded body layer twice or more, a three-dimensional model including a plurality of the molded body layers is formed.
A method of manufacturing a three-dimensional structure.

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