JP4906336B2 - Photocurable resin composition - Google Patents

Description

  The present invention relates to a photocurable resin composition and a method for producing a three-dimensional structure using the photocurable resin composition. More specifically, the present invention has a small volume shrinkage at the time of curing, and can produce a three-dimensional modeled object having a desired size and appearance with high modeling accuracy and dimensional accuracy, and is suitable for optical modeling. Viscosity, excellent handling during stereolithography, excellent storage stability without significant increase in viscosity or gelation even when stored for a long time in an uncured state, and high curing sensitivity and active energy A photo-curable resin composition that can be cured in a short time when irradiated with a wire, and can produce a photo-cured product such as a three-dimensional modeled product that has excellent mechanical properties and heat resistance with high productivity, and The present invention relates to a method for producing a three-dimensional structure using a photocurable resin composition.

In recent years, a method for three-dimensional optical modeling of a liquid photocurable resin composition based on data input to a three-dimensional CAD has achieved good dimensional accuracy without producing a mold or the like. Have been widely adopted.
As a typical example of the optical three-dimensional modeling method, a predetermined thickness is obtained by selectively irradiating an ultraviolet laser controlled by a computer so that a desired pattern is obtained on the liquid surface of the liquid photocurable resin placed in a container. Then, a liquid resin for one layer is supplied onto the cured layer, and similarly cured by irradiation with an ultraviolet laser in the same manner as described above. The method of obtaining a molded article can be mentioned. With this optical three-dimensional modeling method, it is possible to easily obtain a model having a considerably complicated shape in a relatively short time.

  In recent years, instead of the above-described conventional method using spot-like ultraviolet laser light, a micro liquid crystal shutter capable of shielding and transmitting light in a micro dot area between the light source and the surface of the photocurable resin composition. A liquid crystal drawing mask in which a plurality of liquid crystal drawing masks are arranged, or a sheet drawing mask made of a so-called DMD (digital micromirror device) in which a plurality of digital micromirror shutters are arranged in a sheet shape is arranged, Then, a three-dimensional modeling technique has been proposed in which light is irradiated onto the liquid surface of the photocurable resin to sequentially form a photocurable resin layer having a predetermined cross-sectional shape pattern. Since the optical three-dimensional modeling technique using a drawing mask can form a cross-sectional shape pattern that is photocured by irradiating light onto a modeling surface made of a photo-curable resin composition at once in a planar shape. It is possible to greatly improve the optical modeling speed as compared with the spotting method using a spot-like ultraviolet laser.

  Optical modeling in both optical three-dimensional modeling using spot-shaped ultraviolet laser light and three-dimensional modeling that irradiates the modeling surface with light in a predetermined cross-sectional shape pattern via a planar drawing mask. The photo-curable resin composition used in the invention has a small shrinkage rate at the time of photo-curing, which is extremely important in order to smoothly produce a three-dimensional modeled object having a desired size and appearance with high modeling accuracy and dimensional accuracy. . In particular, in optical three-dimensional modeling using a planar drawing mask, a relaxation phenomenon that suppresses shrinkage by simultaneously fixing two axes (for example, the x axis and the y axis) of x, y, and z coordinates by light. Is limited only to the z-axis, so there is a tendency for “warping” due to shrinkage during photocuring to be greater than in optical modeling using spot-like ultraviolet laser light, and it has the desired dimensional accuracy and appearance. It is difficult to manufacture a high-quality three-dimensional model without distortion or deformation. From this point, light with a smaller shrinkage rate during photocuring can be used effectively not only in optical three-dimensional modeling using spot-shaped ultraviolet laser light but also in optical three-dimensional modeling using a planar drawing mask. Development of a curable resin composition is required.

  Furthermore, in conjunction with the reduction in shrinkage during photocuring, the photocurable resin composition has a low viscosity suitable for photofabrication and is excellent in handleability during photofabrication. Optimum storage stability with no significant increase in viscosity or gelation even after storage, high curing sensitivity, curing in a short time when irradiated with active energy rays, and using an ultraviolet laser with high energy intensity High-intensity discharge lamps (HID lamps) such as ultra-high-pressure mercury lamps, high-pressure mercury lamps, xenon lamps, metal halide lamps, etc. are often used as light sources. Even in optical three-dimensional modeling using a planar drawing mask, optical modeling can be carried out with high productivity, and the three-dimensional model obtained has excellent physical properties such as mechanical properties, etc. Is required.

  As a photocurable resin composition for optical modeling, conventionally, an acrylate photocurable resin composition, a urethane acrylate photocurable resin composition, an epoxy photocurable resin composition, and an epoxyacrylate photocurable resin are used. Resin compositions and vinyl ether photocurable resin compositions have been proposed and used. Among these, an epoxy-based photocurable resin composition has recently attracted attention because it can form a molded article having excellent dimensional accuracy. However, since the epoxy compound as the main component is limited to the alicyclic epoxy compound and the aliphatic epoxy compound and the range of usable compounds is narrow, there is a limit in terms of materials to obtain a higher performance shaped article. On the other hand, very many types of acrylate-based photocurable resin compositions and urethane acrylate-based photocurable resin compositions have been developed, and urethane acrylate-based photocurable resin compositions have polar groups in the molecule. Thus, a three-dimensional structure excellent in heat resistance and mechanical properties can be obtained relatively easily.

  However, for the purpose of obtaining a three-dimensional structure with improved mechanical properties, if a method of introducing a large crystalline group into the molecule of the photocurable resin or increasing the crosslink density is adopted, the volume at the time of curing is increased. Shrinkage increases, warping occurs during modeling, making modeling difficult, and reducing the dimensional accuracy of the resulting model and poor appearance. On the other hand, if the crosslink density is lowered in order to reduce the warpage, the physical properties are lowered, and the reduction in volume shrinkage at the time of curing (reduction in warpage) and the physical properties of the optically shaped object are in a trade-off relationship.

  From the above points, the present inventors have a low viscosity suitable for stereolithography, have a small shrinkage ratio at the time of photocuring, and cure in a short time, and are excellent in characteristics such as heat resistance and mechanical characteristics. Research and development have been conducted for the purpose of obtaining a photo-curable resin composition capable of producing a three-dimensional model with high modeling accuracy and dimensional accuracy. And while the photocurable resin composition containing a specific polyfunctional urethanized acrylic compound having three or more urethane (meth) acrylate groups and a photopolymerization initiator has a low viscosity suitable for optical three-dimensional modeling, It was found that the shrinkage rate at the time of photocuring was small, photocuring in a short time, and that the photofabricated product obtained from the photocurable resin composition was also excellent in heat resistance, mechanical properties, etc. (See Patent Document 1).

  As a result of further investigations by the inventors based on the invention of Patent Document 1, an optical solid that irradiates light in a planar shape onto a modeling surface made of a photocurable resin composition through a planar drawing mask. In modeling, as described above, “warping” due to volume shrinkage at the time of photocuring occurs greatly, and it has been found that it is necessary to develop a photocurable resin composition having a further reduced shrinkage rate at the time of photocuring.

  Furthermore, in optical three-dimensional modeling, especially three-dimensional modeling in which optical modeling is performed through a planar drawing mask using light with low energy intensity, the modeling time is shortened together with further reduction of the shrinkage rate during photocuring. From the viewpoint of improving productivity, it has been found desirable to further increase the photocuring sensitivity of the photocurable resin composition.

For the purpose of achieving both improved reactivity of the photocurable resin composition and improved physical properties of the three-dimensional structure, urethane di (meth) acrylate, monofunctional diluent monomer, polyalkylene glycol di (meth) acrylate, and light It has been proposed to further add a curing accelerator such as triethylamine, methyldiethylamine, diethanolamine or the like to a photocurable resin composition containing a polymerization initiator (see Patent Document 2, especially paragraph 0021).
However, the photocurable resin composition containing a curing accelerator such as diethanolamine described in Patent Document 2 is liable to increase in viscosity or gel in a short period of time, and is inferior in storage stability and handleability. It is not necessarily suitable for stereolithography.

In addition, urethane (meth) acrylate oligomer, (meth) acrylate monomer, photopolymerization initiator having an ethylenically unsaturated bond in the molecule, or a high molecular weight photopolymerization initiator obtained by polymerizing the ethylenically unsaturated bond And a photocurable resin composition for gaskets containing an amino group-containing acrylate photosensitizer has been proposed (see Patent Document 3).
However, the photocurable resin composition of this patent document 2 is for gaskets, and the optical energy level used at the time of hardening differs greatly from optical three-dimensional modeling. Moreover, in the photocurable resin composition of Patent Document 3, the present inventors have used an optical three-dimensional modeling using a photocurable resin composition to which dimethylaminoethyl acrylate has been added as an amino group-containing acrylate photosensitizer. As a result, it was found that the photo-curable resin composition has insufficient storage stability, and when stored, it tends to cause dust and gelation and is not suitable for optical three-dimensional modeling. In addition, when the present inventors performed optical three-dimensional modeling using the photocurable resin composition before the dust and gelation occurred, the three-dimensional model obtained thereby has a tensile strength, tensile elongation, etc. The mechanical strength represented was low, and it was colored dark brown and the appearance was poor. Moreover, in this photocurable resin composition of Patent Document 3, “EB-7100” (manufactured by Daicel Sydec Co., Ltd.) used in Examples of Patent Document 3 was added as an amino group-containing acrylate photosensitizer. When the present inventors performed optical three-dimensional modeling using a thing, the three-dimensional molded item obtained by that was a thing with low mechanical strength.

Japanese Patent No. 3705508 JP-A-9-194540 JP 2004-26919 A Paul F. Jacobs, “Rapid Prototyping & Manufacturing, Fundamentals of Stereo-Lithography”, “Society of Manufacturing Engineers”, 1992, p. 28-39.

An object of the present invention is to provide a photocurable resin composition having a small shrinkage ratio at the time of photocuring and capable of producing a desired shaped article with high dimensional accuracy and shaping accuracy.
Furthermore, the purpose of the present invention is low viscosity and excellent handleability in combination with the above-described characteristics of low shrinkage, and it is suitable for stereolithography and the like without significant increase in viscosity or gelation even after long-term storage. It can maintain a low viscosity, has high curing sensitivity with active energy rays, and can produce photocured products such as three-dimensional objects with high productivity in a reduced irradiation time of active energy rays. It is providing the photocurable resin composition which can manufacture photocured materials, such as an optical three-dimensional molded item which is excellent in an optical characteristic.
Furthermore, the object of the present invention is to provide a method for producing a three-dimensional object by performing optical three-dimensional modeling using the photocurable resin composition.

In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, an ester derived from a bulky alcohol compound having 5 to 20 carbon atoms with respect to the specific multifunctional urethane (meth) acrylate compound described in Patent Document 1 developed by the present inventors. When a specific monofunctional acrylate compound having a group, another acrylate compound, and a radical polymerization initiator are blended, the shrinkage rate during photocuring is further reduced, and not only stereolithography using a spot-like ultraviolet laser, but also a planar drawing mask Even when used for optical modeling using a photocurable resin composition, the volume shrinkage of the photocured product is further reduced, and a photocurable resin composition capable of producing a target three-dimensional modeled product with high modeling accuracy and dimensional accuracy is obtained. It was found that it can be obtained.
Furthermore, the present inventors have not only reduced the shrinkage rate at the time of photocuring, but also have a low viscosity suitable for optical three-dimensional modeling, and the photocurable resin composition is left to stand for a long time. In addition, there is no significant increase in viscosity or gelation, excellent long-term storage stability, easy handling, and effective use in optical three-dimensional modeling, three-dimensional modeling obtained from the photocurable resin composition, etc. It was found that the photocured product was excellent in various properties such as mechanical properties.
In addition, when the specific acrylate compound having a tertiary amino group is used as a part of the other acrylate compound in the photocurable resin composition, the present inventors improve the curing sensitivity and shorten the time. The present invention has been completed based on these various findings.

That is, the present invention
(1) (i) the following general formula (I);

｛式中、Ｒ¹は水素原子またはメチル基、ｄは１または２であって、ｄが２のときは一方または両方のＲ¹がメチル基であり、Ａはジオールまたはトリオール残基、Ｄは２価または３価の非置換または置換された炭化水素基、Ｇは式：−（ＣＨ₂ＣＨ₂Ｏ）ｇ−（式中ｇは１〜４の整数を示す）で表される（ポリ）エチレンオキサイド基、式：−［（ＣＨ₂ＣＨ（ＣＨ₃）Ｏ］ｈ−（式中ｈは１〜４の整数を示す）で表される（ポリ）プロピレンオキサイド基または式：−（ＣＨ₂ＣＨ₂Ｏ）ｊ［（ＣＨ₂ＣＨ（ＣＨ₃）Ｏ］ｋ−（式中ｊおよびｋはそれぞれ１〜３の整数であってｊとｋの合計が２〜４である）で表される（ポリ）エチレンオキサイドプロピレンオキサイド基、Ｒ²は水素原子またはアルキル基、ｅは１または２、そしてｆは３または４を示す。｝
で表されるウレタン化アクリル化合物（Ｉ）の少なくとも１種；
（ii） 下記の一般式（II）；

{Wherein R ¹ is a hydrogen atom or a methyl group, d is 1 or 2, and when d is 2, one or both R ¹ is a methyl group, A is a diol or triol residue, D is divalent or trivalent unsubstituted or substituted hydrocarbon radical, G is represented by the formula _{:-( CH 2 CH 2 O) g-} (g wherein is an integer of 1 to 4) (poly) Ethylene oxide group, (poly) propylene oxide group represented by the formula:-[(CH ₂ CH (CH ₃ ) O] h- (where h represents an integer of 1 to 4) or formula:-(CH ₂ represented by _{CH 2 O) j [(CH} 2 CH (CH 3) O] k- ( sum of an integer of each j and k in the formula 1 to 3 j and k is 2 to 4) (poly) ethylene oxide-propylene oxide group, R ² is a hydrogen atom or an alkyl group, e is 1 or 2, and f Or an 4.}
At least one of urethanized acrylic compounds (I) represented by:
(Ii) the following general formula (II);

（式中、Ｒ³は炭素数５〜２０の１価の炭化水素基を示す。）
で表される単官能アクリレート（II）；
（iii） 上記ウレタン化アクリル化合物（Ｉ）および単官能アクリレート（II）以外の他の（メタ）アクリレート化合物；および、
（iv） 活性エネルギー線感受性ラジカル重合開始剤；
を含有する光硬化性樹脂組成物であって、
ウレタン化アクリル化合物（Ｉ）および単官能アクリレート（II）以外の他の（メタ）アクリレート化合物の一部として、下記の一般式（III）；

(In the formula, R ³ represents a monovalent hydrocarbon group having 5 to 20 carbon atoms.)
A monofunctional acrylate (II) represented by:
(Iii) (meth) acrylate compounds other than the urethanized acrylic compound (I) and the monofunctional acrylate (II); and
(Iv) an active energy ray sensitive radical polymerization initiator;
A photocurable resin composition comprising:
As a part of other (meth) acrylate compounds other than the urethanized acrylic compound (I) and the monofunctional acrylate (II), the following general formula (III);

［式中、Ｒ ⁴ およびＲ ⁵ は互いに同じか又は異なるアルキル基またはアラルキル基を示し、Ｒ ⁶ は（ｍ＋ｎ）価のアクリレート残基を示し、ｍおよびｎはそれぞれ独立して１〜５の整数であり、ｍ＋ｎは２〜６である。］
で表される３級アミノ基含有アクリレート化合物（III）を、光硬化性樹脂組成物の全質量に基づいて、０．１〜１０質量％の割合で含有することを特徴とする光硬化性樹脂組成物である。
なお、本明細書でいう「活性エネルギー線」とは、紫外線、電子線、Ｘ線、放射線、高周波などのような光硬化性樹脂組成物を硬化させ得るエネルギー線をいう。

[Wherein, R ⁴ and R ⁵ represent the same or different alkyl group or aralkyl group, R ⁶ represents an (m + n) -valent acrylate residue, and m and n are each independently an integer of 1 to 5 And m + n is 2-6. ]
A photocurable resin comprising a tertiary amino group-containing acrylate compound (III) represented by formula (III) in a proportion of 0.1 to 10% by mass based on the total mass of the photocurable resin composition. It is a composition.
As used herein, the term “active energy rays” refers to energy rays that can cure a photocurable resin composition such as ultraviolet rays, electron beams, X-rays, radiation, and high frequencies.

And this invention,
(2) Based on the total mass of the photocurable resin composition, the urethanized acrylic compound (I) is 20 to 55 mass%, the monofunctional acrylate (II) is 20 to 55 mass%, and other than the above two. The photocurable resin composition according to the above (1), which contains 20 to 55% by mass of a (meth) acrylate compound and 1 to 10% by mass of an active energy ray-sensitive radical polymerization initiator;
( 3 ) The photocurable resin composition according to (1) or (2) , which is for optical three-dimensional modeling;
It is.
Furthermore, the present invention provides
( 4 ) A method for producing a three-dimensional model by performing optical three-dimensional modeling using the photocurable resin composition according to any one of (1) to ( 3 ).

The photocurable resin composition of the present invention has a small shrinkage ratio at the time of curing. Therefore, by performing optical modeling using the photocurable resin composition of the present invention, there is no warpage or deformation, and the appearance as intended. In addition, a photocured product such as a three-dimensional modeled object having dimensions can be manufactured smoothly with high dimensional accuracy and high modeling accuracy.
The photocurable resin composition of the present invention has a low viscosity suitable for optical modeling and the like, and even when stored for a long period of time, the viscosity does not increase significantly and gelation does not occur, and storage stability and handleability are improved. It is excellent and can be used effectively for optical three-dimensional modeling.
The photocurable resin composition of the present invention, among which the photocurable resin composition of the present invention containing the above-mentioned tertiary amino group-containing acrylate compound (III) as another acrylate compound has a curing sensitivity by active energy rays. Since the photocuring is performed with high and shortened light irradiation time, a photocured product such as a high-quality three-dimensional modeled product with further excellent dimensional accuracy can be manufactured with high productivity in a short modeling time.
By using the photocurable resin composition of the present invention, it is possible to smoothly produce a three-dimensional structure that is excellent in properties such as mechanical properties and heat resistance.

The present invention is described in detail below.
The photocurable resin composition of the present invention has the following general formula (I):

｛式中、Ｒ¹は水素原子またはメチル基、ｄは１または２であって、ｄが２のときは一方または両方のＲ¹がメチル基であり、Ａはジオールまたはトリオール残基、Ｄは２価または３価の非置換または置換された炭化水素基、Ｇは式：−（ＣＨ₂ＣＨ₂Ｏ）ｇ−（式中ｇは１〜４の整数を示す）で表される（ポリ）エチレンオキサイド基、式：−［（ＣＨ₂ＣＨ（ＣＨ₃）Ｏ］ｈ−（式中ｈは１〜４の整数を示す）で表される（ポリ）プロピレンオキサイド基または式：−（ＣＨ₂ＣＨ₂Ｏ）ｊ［（ＣＨ₂ＣＨ（ＣＨ₃）Ｏ］ｋ−（式中ｊおよびｋはそれぞれ１〜３の整数であってｊとｋの合計が２〜４である）で表される（ポリ）エチレンオキサイドプロピレンオキサイド基、Ｒ²は水素原子またはアルキル基、ｅは１または２、そしてｆは３または４を示す。｝
で表されるウレタン化アクリル化合物（Ｉ）の少なくとも１種を含有する。

{Wherein R ¹ is a hydrogen atom or a methyl group, d is 1 or 2, and when d is 2, one or both R ¹ is a methyl group, A is a diol or triol residue, D is divalent or trivalent unsubstituted or substituted hydrocarbon radical, G is represented by the formula _{:-( CH 2 CH 2 O) g-} (g wherein is an integer of 1 to 4) (poly) Ethylene oxide group, (poly) propylene oxide group represented by the formula:-[(CH ₂ CH (CH ₃ ) O] h- (where h represents an integer of 1 to 4) or formula:-(CH ₂ represented by _{CH 2 O) j [(CH} 2 CH (CH 3) O] k- ( sum of an integer of each j and k in the formula 1 to 3 j and k is 2 to 4) (poly) ethylene oxide-propylene oxide group, R ² is a hydrogen atom or an alkyl group, e is 1 or 2, and f Or an 4.}
The urethanized acrylic compound (I) represented by the formula (I) is contained.

In the urethanized acrylic compound (I) represented by the above general formula (I) used in the photocurable resin composition of the present invention, R ¹ is a hydrogen atom or a methyl group, and d is 1 or 2. When d is 2, the group R ¹ in one or both of the _two groups; CH ₂ ═C (R ¹ ) —COO— must be a methyl group. In the urethanized acrylic compound (I), when d is 2, two (meth) acryloyloxy groups; both groups R ^{1 of} CH ₂ ═C (R ¹ ) —COO— are hydrogen atoms. Toxic, carcinogenic and skin irritating glycerin diacrylate must be passed through, which is not preferable because it cannot be used substantially.

  In the urethanized acrylic compound (I), the group A is a diol or triol residue (that is, a group after removing a hydroxyl group from the diol or triol). Examples of the group A include diols or triol residues such as aliphatic diols having 2 to 5 carbon atoms, alicyclic diols, aromatic diols, aliphatic triols, alicyclic triols, and aromatic triols. Among them, the group A includes diol residues such as ethylene glycol, propylene glycol, butylene glycol, ethoxylated bisphenol A, spiroglycol, glycerin, trimethylolpropane, 5-methyl-1,2,4-heptanetriol, 1, It is preferably a triol residue such as 2,6-hexanetriol, more preferably an alcohol residue of ethylene glycol or glycerin, and still more preferably an alcohol residue of ethylene glycol.

In the urethanized acrylic compound (I), the group D is a divalent or trivalent unsubstituted or substituted hydrocarbon group, and the group D is an unsubstituted or substituted aliphatic or aromatic group having 6 to 20 carbon atoms. An aliphatic or alicyclic divalent or trivalent hydrocarbon group is preferred.
The urethanized acrylic compound (I) can be preferably produced using a (meth) acrylic acid ester and a polyisocyanate compound. From this point, the group D was used to produce the urethanized acrylic compound (I). A polyisocyanate compound, that is, a divalent or trivalent residue excluding an isocyanate group of a diisocyanate compound or a triisocyanate compound is preferable. More specifically, preferable examples of the group D in the urethanized acrylic compound (I) include isophorone group, tolylene group, 4,4′-diphenylmethane group, naphthylene group, xylylene group, phenylene group, 3,3′- Examples include dichloro-4,4′-phenylmethane group, toluylene group, hexamethylene group, 4,4′-dicyclohexylmethane group, hydrogenated xylylene group, hydrogenated diphenylmethane group, triphenylenemethane group, and tetramethylxylene group. be able to. Among them, it is more preferable that the group D is an isophorone group and / or a tolylene group. In that case, a three-dimensionally shaped article or molded article obtained from the photocurable resin composition of the present invention containing the urethanized acrylic compound (I) This makes it easy to balance the shrinkage rate and heat resistance of a photocured product such as a product.

  In the urethanized acrylic compound (I), e = 1 when the group D is a divalent hydrocarbon group, and e = 2 when the group D is a trivalent hydrocarbon. That is, to prepare the urethanized acrylic compound (I), e = 1 when a diisocyanate compound is used as the polyisocyanate compound, and e = 2 when a triisocyanate compound is used.

In the urethanized acrylic compound (I), the group G is a (poly) ethylene oxide group represented by the formula: — (CH ₂ CH ₂ O) g— (wherein g represents an integer of 1 to 4), the formula: _{- [(CH 2 CH (CH} 3) O] h- (h wherein is an integer of 1 to 4) (poly) propylene oxide group, or a group of the formula _{:-( CH 2 CH 2 O) j} [ _{(CH 2 CH (CH 3)} O] k- ( sum of a and j and k each represent an integer of the j and k in the formula 1-3 are represented by a 2 to 4) (poly) ethylene oxide-propylene In the (poly) ethylene oxide group or (poly) propylene oxide group represented by the above formula, g or h is preferably an integer of 1 to 3, and more preferably 1 or 2. preferable.
In the (poly) ethylene oxide propylene oxide group represented by the above formula, the sum of j and k is preferably 2 or 3, and more preferably 2. In particular, the group G in the urethanized acrylic compound (I) is represented by the formula:-[(CH ₂ CH (CH ₃ ) O] h- (where h is preferably 1 to 3, more preferably 1 to 2). (Poly) propylene oxide group having a higher heat distortion temperature, better heat resistance, smaller volume shrinkage during curing, and a relatively low viscosity photocurable resin composition. This is preferable.

In the above group G, when g and h are larger than 4, even if an appropriate one is selected as the other (meth) acrylate compound described above, the photocured product obtained using the photocurable resin composition The heat distortion temperature is not sufficiently high, and the heat resistance does not reach a desired level.
On the other hand, when g or h is 0, that is, when the urethanized acrylic compound (I) does not have an ethylene oxide group or a propylene oxide group, an improvement in heat resistance is observed, but volume shrinkage during photocuring is large. The target molded product or three-dimensional model cannot be manufactured with high dimensional accuracy, and gelation tends to occur when a urethane-modified acrylic compound is synthesized, and the viscosity of the resulting urethane-modified acrylic compound is abnormal. Becomes too high to be used in the photocurable resin composition of the present invention.

In the urethanized acrylic compound (I), the group R ² is a hydrogen atom or an alkyl group, and f is 3 or 4. The group R ² is preferably a lower alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group.

Although not limited, the following can be mentioned as an example of the urethanized acrylic compound (I) which can be used with the photocurable resin composition of this invention.
(1) In the above general formula (I), d is 1, R ¹ is a hydrogen atom or a methyl group, e is 1, and D is a divalent unsubstituted or substituted aromatic, aliphatic or alicyclic hydrocarbon. A urethanized acrylic compound (I) having a group f of 4 and having the formula: CH ² ═C (R ¹ ) COO—A—OOC—NH—D with respect to its carbon atom centered on one carbon atom A urethane-modified acrylic compound in which four urethane acrylate groups represented by —NH—COO—G—CH ₂ — are bonded.

(2) In the above general formula (I), d is 1, R ¹ and R ² are hydrogen atoms or methyl groups, e is 1, and D is divalent unsubstituted or substituted aromatic, aliphatic, alicyclic Group urethanized acrylic compound (I) wherein f is 3 and is centered on one carbon atom with respect to that carbon atom (ie the carbon atom to which the remaining group R ² is bonded) : A urethane-modified acrylic compound in which three urethane acrylate groups represented by CH ₂ ═C (R ¹ ) COO—A—OOC—NH—D—NH—COO—G—CH ₂ — are bonded.

(3) In the above general formula (I), d is 2, one of two R ¹ is a hydrogen atom and the other is a methyl group, e is 1, and D is divalent unsubstituted or substituted Aromatic, aliphatic, alicyclic hydrocarbon group, and urethanized acrylic compound (I) wherein r is 4, and the formula: [CH ₂ = C ( R ¹ ) COO] ₂ -A-OOC-NH-D-NH-COO-G-CH ₂ -represents a urethane-modified acrylic compound in which four urethane acrylate groups are bonded [that is, a (meth) acrylate group. Urethane acrylic compound (I) having 8 per molecule].

(4) In the above general formula (I), d is 2, one of the two R ¹ is a hydrogen atom, the other is a methyl group, R ² is a hydrogen atom or a methyl group, e is 1, and D is divalent. A non-substituted or substituted aromatic, aliphatic or alicyclic hydrocarbon group, f is a urethanized acrylic compound (I) having a carbon atom centered on one carbon atom (that is, the remaining Urethane represented by the formula: [CH ₂ ═C (R ¹ ) COO] ₂ —A—OOC—NH—D—NH—COO—G—CH ₂ — to the carbon atom to which the group R 2 is bonded. Urethane-modified acrylic compound having three acrylate groups bonded [ie, urethane-modified acrylic compound (I) having six (meth) acrylate groups in one molecule].

(5) In the above general formula (I), d is 1, R ¹ is a hydrogen atom or a methyl group, e is 2, and D is trivalent unsubstituted or substituted aromatic, aliphatic, alicyclic A urethanized acrylic compound (I) having an aromatic hydrocarbon group f of 4 and having the formula: [CH ₂ = C (R ¹ ) COO-A-OOC with respect to the carbon atom centered on one carbon atom _{-NH] 2 -D-NH-COO} -G-CH 2 - urethane acrylate compound urethane acrylate group is four bond represented by [ie (meth) urethane having 8 acrylate groups in one molecule Acrylic Compound (I)].

(6) In the above general formula (I), d is 1, R ¹ and R ² are a hydrogen atom or a methyl group, e is 2, and D is trivalent unsubstituted or substituted aromatic or aliphatic , An alicyclic hydrocarbon group, and a urethane-modified acrylic compound (I) having f of 3, wherein the formula is [CH ₂ ═C (R ¹ ) COO with respect to the carbon atom centered on one carbon atom. -A-OOC-NH] ₂ -D-NH-COO-G-CH ₂ — A urethane-modified acrylic compound in which three urethane acrylate groups represented by the formula [that is, a (meth) acrylate group is contained in one molecule 6 urethane-modified acrylic compounds (I)].

(7) In the above general formula (I), d is 2, one of two R ¹ is a hydrogen atom and the other is a methyl group, e is 2, and D is trivalent unsubstituted or substituted An urethanated acrylic compound (I) having an aromatic, aliphatic, alicyclic hydrocarbon group, and f of 4, wherein the compound is represented by the formula: {[CH ₂ ═C (R ¹ ) COO] ₂ —A—OOC—NH} ₂ —D—NH—COO—G—CH ₂ — A urethane-modified acrylic compound in which four urethane acrylate groups are bonded [ie, (meth) Urethane acrylic compound (I) having 16 acrylate groups in one molecule].

(8) In the above general formula (I), d is 2, one of the two R ¹ is a hydrogen atom and the other is a methyl group, R ² is a hydrogen atom or a methyl group, e is 2, and D is A trivalent unsubstituted or substituted aromatic, aliphatic or alicyclic hydrocarbon group, or a urethanized acrylic compound (I) wherein f is 3, wherein the carbon atom is centered on one carbon atom. In contrast, three urethane acrylate groups represented by the formula: {[CH ₂ ═C (R ¹ ) COO] ₂ —A—OOC—NH} ₂ —D—NH—COO—G—CH ₂ — Urethane-modified acrylic compound [that is, urethane-modified acrylic compound (I) having 12 (meth) acrylate groups in one molecule].

  The photocurable resin composition of the present invention has the following general formula (II) together with the urethanized acrylic compound (I) described above;

（式中、Ｒ³は炭素数５〜２０の１価の炭化水素基を示す。）
で表される単官能アクリレート（II）を含有する。

(In the formula, R ³ represents a monovalent hydrocarbon group having 5 to 20 carbon atoms.)
The monofunctional acrylate (II) represented by these is contained.

In the monofunctional acrylate (II), R ³ is a monovalent hydrocarbon group having 5 to 20 carbon atoms, and preferably a monovalent hydrocarbon group having 8 to 20 carbon atoms.
Examples of R ³ include monovalent alkyl groups having 5 to 20 carbon atoms, alicyclic hydrocarbon groups, alkyl groups having alicyclic rings, bridged cyclic hydrocarbon groups having bicyclo rings, tricyclo rings, and the like, aralkyl Examples include groups.
Specific examples when R ³ is an alkyl group having 5 to 20 carbon atoms include pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecanyl group, dodecanyl group (lauryl group), and tridecanyl group. Tetradecanyl group, pentadecanyl group, hexadecanyl group, heptadecanyl group (stearyl group), octadecanyl group, nonadecanyl group and the like.
Among them, R ³ is preferably an alkyl group having 6 to 14 carbon atoms from the viewpoints of reduction of shrinkage ratio during photocuring and low viscosity, and particularly an alkyl group having 8 to 12 carbon atoms. It is preferable.

Examples of the case where R ³ is an alicyclic alkyl group having 5 to 20 carbon atoms or an alkyl group having an alicyclic ring include a cyclohexyl group, a methyl group in which one of the hydrogen atoms is substituted with a cyclohexyl group, Examples thereof include an ethyl group in which one is substituted with a cyclohexyl group.
Examples of the case where R ³ is a bridged cyclic hydrocarbon group having 5 to 20 carbon atoms include a bicyclopentanyl group, a tricyclodecanylmethyl group, an isobornyl group, a bicycloheptyl group, a bicyclooctyl group, and a tricyclo group. An undecanyl group etc. can be mentioned.
Among them, when R ³ is a bridged cyclic hydrocarbon group, a bicyclocyclic hydrocarbon group or a tricyclocyclic hydrocarbon group is preferable from the viewpoint of reducing the shrinkage rate during photocuring.
Further, specific examples when R ³ is an aralkyl group include a benzyl group and a phenethyl group.

Among the above-described monofunctional acrylates (II), R ³ is a monofunctional acrylate in which R ³ is a long-chain alkyl group having 8 to 20 carbon atoms, a bicyclo hydrocarbon group, or a tricyclo hydrocarbon group, specifically, Lauryl acrylate, isobornyl acrylate, bicyclopentanyl acrylate, and tricyclodecane methanol acrylate are more preferably used because of their low viscosity and low shrinkage during photocuring. In the present invention, as monofunctional acrylate (II), only one type of monofunctional acrylate (II) in which R ³ is the above-described preferred group may be used, or two or more types of monofunctional acrylate (II) may be used. May be used in combination.

The photocurable resin composition of this invention contains other (meth) acrylate compounds other than these with the urethanated acrylic compound (I) and monofunctional acrylate (II) described above.
As other (meth) acrylate compounds, any (meth) acrylate compounds other than urethanized acrylic compounds (I) and monofunctional acrylates (II) that can be polymerized in the presence of an active energy ray polymerization initiator. Good. The other (meth) acrylate compound may be a monofunctional (meth) acrylate compound having one (meth) acryloyl group or a polyfunctional (meth) acrylate compound having two or more (meth) acryloyl groups. It may be present or a combination thereof.

  Other (meth) acrylate compounds include, for example, urethane (meth) acrylate compounds other than urethanized acrylic compound (I), epoxy (meth) acrylate compounds [reaction products of epoxy compounds and (meth) acrylic acid ], Ester (meth) acrylate compounds other than monofunctional acrylate (II) [(meth) acrylic ester of alcohol], polyester (meth) acrylate, polyether (meth) acrylate, other (meth) acrylate compounds, etc. Can be mentioned.

  As the above-mentioned epoxy (meth) acrylate compound, epoxy (meth) obtained by reaction of at least one of an aromatic epoxy compound, an alicyclic epoxy compound and an aliphatic epoxy compound with (meth) acrylic acid. Examples include acrylate-based reaction products. Among them, an epoxy (meth) acrylate reaction product obtained by reaction of an aromatic epoxy compound and (meth) acrylic acid is preferably used. Specific examples include bisphenol compounds such as bisphenol A and bisphenol F or alkylene thereof. By reacting glycidyl ether obtained by reaction of an oxide adduct with an epoxidizing agent such as epichlorohydrin with (meth) acrylic acid, epoxy (meth) acrylate, epoxy novolac resin and (meth) acrylic acid are reacted. Examples thereof include an epoxy (meth) acrylate reaction product obtained.

The above ester (meth) acrylate compounds other than the monofunctional acrylate (II) include aromatic alcohols, aliphatic alcohols, alicyclic alcohols and / or alkylene oxide additions having at least one hydroxyl group in the molecule. The (meth) acrylate obtained by reaction of a body and (meth) acrylic acid can be mentioned.
Specifically, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, tetrahydro Furfuryl (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, neopentyl glycol Di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) Acrylate, dipentaerythritol hexa (meth) acrylate and other dipentaerythritol poly (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane dimethanol diacrylate, cyclohexane dimethanol diacrylate, diol, triol, tetra Examples include (meth) acrylates of alkylene oxide adducts of polyhydric alcohols such as all and hexaol, ethylene oxide-modified bisphenol A diacrylate, propylene oxide-modified bisphenol A diacrylate, and the like.

  Among them, as a (meth) acrylate of alcohols, a polyfunctional (meth) acrylate having two or more (meth) acryl groups in one molecule obtained by reaction of a polyhydric alcohol and (meth) acrylic acid. For example, tricyclodecane dimethanol diacrylate, dipentaerythritol poly (meth) acrylate, cyclohexane dimethanol diacrylate, aliphatic diacrylate, polyfunctional acrylate of aliphatic polyol, alicyclic diacrylate, and ethylene oxide or propylene oxide modification From the viewpoint of reactivity, it is preferable to use bisphenol A diacrylate.

Moreover, as above-mentioned polyester (meth) acrylate which can be used as another (meth) acrylate compound, the polyester (meth) acrylate obtained by reaction of hydroxyl-containing polyester and (meth) acrylic acid can be mentioned.
Furthermore, as the above-mentioned polyether (meth) acrylate that can be used as another (meth) acrylate compound, polyether acrylate obtained by reaction of a hydroxyl group-containing polyether and acrylic acid can be exemplified.

  In the photocurable resin composition of the present invention, the polymerization rate is such that the other (meth) acrylate compounds used together with the urethanized acrylic compound (I) and the monofunctional acrylate (II) are acrylate compounds rather than methacrylate compounds. Is preferable from the viewpoint of fast.

  The photocurable resin composition of the present invention has the following general formula (III) as a part of other (meth) acrylate compounds:

［式中、Ｒ⁴およびＲ⁵は互いに同じか又は異なるアルキル基またはアラルキル基を示し、Ｒ⁶は（ｍ＋ｎ）価のアクリレート残基を示し、ｍおよびｎはそれぞれ独立して１〜５の整数であり、ｍ＋ｎは２〜６である。］
で表される３級アミノ基含有アクリレート化合物（III）を含有することができ、３級アミノ基含有アクリレート化合物（III）を含有することによって光硬化性樹脂組成物の光硬化感度の向上、収縮率の低減などを図ることができる。

[Wherein, R ⁴ and R ⁵ represent the same or different alkyl group or aralkyl group, R ⁶ represents an (m + n) -valent acrylate residue, and m and n are each independently an integer of 1 to 5 And m + n is 2-6. ]
The tertiary amino group-containing acrylate compound (III) represented by the formula (III) can be contained, and by containing the tertiary amino group-containing acrylate compound (III), the photocuring resin composition has improved photocuring sensitivity and shrinkage. The rate can be reduced.

In the tertiary amino group-containing acrylate compound (III) represented by the above general formula (III), R ⁴ and R ⁵ are the same or different alkyl groups or aralkyl groups.
When R ⁴ and / or R ⁵ is an alkyl group, it is preferably an alkyl group having 1 to 5 carbon atoms from the viewpoint of availability of the material. Specific examples of when R ⁴ and / or R ⁵ is an alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a t-butyl group, and an isobutyl group. Can do.
Specific examples of R ⁴ and / or R ⁵ being an aralkyl group include a benzyl group and a phenylethyl group.
Among them, R ⁴ and R ⁵ are preferably a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or a benzyl group from the viewpoint of reactivity.

In the tertiary amino group-containing acrylate compound (III) represented by the general formula (III), R ⁶ is a divalent to hexavalent acrylate residue, of which a divalent to tetravalent, particularly divalent or trivalent acrylate residue is present. A group is preferred from the viewpoint of ease of synthesis. Examples of R ⁶ include divalent to hexavalent, particularly divalent or trivalent aliphatic hydrocarbon groups, alicyclic hydrocarbon groups, bridged cyclic aliphatic hydrocarbon groups, aromatic hydrocarbon groups, Examples thereof include the above-described hydrocarbon groups and ether-type hydrocarbon groups having a substituent such as an ether-type hydrocarbon group and an acryloyloxy group in which a hydrogen group is bonded via an ether oxygen atom.
Among them, R ⁶ is a linear or branched alkylene group having 2 to 12 carbon atoms, a hydrocarbon group having an alicyclic ring, or a hydrocarbon group having a bridged ring from the viewpoint of synthesis and reactivity. preferable.
Specific examples of R ⁶ include groups represented by the following formulas.

（上記式中、Ｅはエチレン基、Ｐはプロピレン基、ｑ、ｒ、ｓ、ｔはそれぞれ独立して１〜１０の整数を示す。）

(In the above formula, E represents an ethylene group, P represents a propylene group, q, r, s, and t each independently represents an integer of 1 to 10)

（式中、Ａは分岐したブチレン基、Ｅはエチレン基、Ｐはプロピレン基、ｕ、ｖおよびｗは１〜１０の整数を示す。）

(In the formula, A is a branched butylene group, E is an ethylene group, P is a propylene group, u, v, and w are integers of 1 to 10.)

  Specific examples of the tertiary amino group-containing acrylate compound (III) include the following compounds.

The production method of the tertiary amino group-containing acrylate compound (III) is not particularly limited, and any method can be used as long as it can smoothly produce the tertiary amino group-containing acrylate compound (III). Good.
Among them, the tertiary amino group-containing acrylate compound (III) is converted into a polyfunctional acrylate compound (IV) represented by the following general formula (IV) and a secondary amine represented by the following general formula (V) ( V) can be smoothly produced by Michael addition reaction.

（式中、Ｒ⁴、Ｒ⁵およびＲ⁶は前記と同じ基を示し、ｍおよびｎは前記と同じ数を示す。）

(Wherein R ⁴ , R ⁵ and R ⁶ represent the same groups as described above, and m and n represent the same numbers as described above.)

The number of tertiary amino groups in the tertiary amino group-containing acrylate compound (IV) is adjusted to 1 by adjusting the amount (number of moles) of the secondary amine (V) to be added to the polyfunctional acrylate compound (IV). It can be an appropriate number in the range of ˜5.
The Michael addition reaction for obtaining the tertiary amino group-containing acrylate compound (III) is generally carried out by using a polyfunctional acrylate compound (IV) and a secondary amine at a temperature of 50 to 60 ° C. under atmospheric pressure without using a solvent and a catalyst. (V) is preferably reacted, whereby the tertiary amino group-containing acrylate compound (III) can be easily and smoothly produced in a high yield.

  In the photocurable resin composition of the present invention, as an active energy ray-sensitive radical polymerization initiator (hereinafter sometimes simply referred to as “radical polymerization initiator”), the radical of the acrylic compound described above when irradiated with active energy rays. Any polymerization initiator capable of initiating polymerization can be used, such as benzyl or its dialkyl acetal compound, phosphine oxide compound, phenyl ketone compound, acetophenone compound, benzoin or its alkyl ether compound, benzophenone compound And thioxanthone compounds.

Specifically, examples of benzyl or a dialkyl acetal compound thereof include benzyl dimethyl ketal and benzyl-β-methoxyethyl acetal.
Examples of the phosphine oxide compound include bisacylphosphine oxide called BAPO and monoacylphosphine oxide called MAPO. Specifically, bis (2,6-dimethoxybenzoyl) -2,4 , 4-trimethylpentylphosphine oxide, 2,4,6- (trimethylbenzoyl) -diphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and the like.
Examples of the phenyl ketone compound include 1-hydroxy-cyclohexyl phenyl ketone.
Examples of the acetophenone compound include diethoxyacetophenone, 2-hydroxymethyl-1-phenylpropan-1-one, 4′-isopropyl-2-hydroxy-2-methyl-propiophenone, and 2-hydroxy-2. -Methyl-propiophenone, p-dimethylaminoacetophenone, p-tert-butyldichloroacetophenone, p-tert-butyltrichloroacetophenone, p-azidobenzalacetophenone and the like.

Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin normal butyl ether, and benzoin isobutyl ether.
Examples of the benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, Michler's ketone, 4,4'-bisdiethylaminobenzophenone, 4,4'-dichlorobenzophenone, and the like.
Examples of the thioxanthone compound include thioxanthone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, and 2-isopropylthioxanthone.

In this invention, 1 type, or 2 or more types of radical polymerization initiators can be mix | blended and used according to desired performance.
Among them, in the present invention, as a radical polymerization initiator, 1-hydroxycyclohexyl phenyl ketone, benzyl dimethyl ketal, 2-hydroxy-2-methyl-1-phenyl-propan-1-one are reactive, It is preferably used from the viewpoint of hue.

The photo-curable resin composition of the present invention is a photo-cured product such as a three-dimensional model obtained by photo-curing, a reduction in shrinkage during photo-curing, a low viscosity suitable for photo-molding, storage stability, an improvement in curing sensitivity, and photo-curing. From the viewpoint of the mechanical properties of the photocurable resin composition, based on the total mass of the photocurable resin composition, the urethanized acrylic compound (I) is 20 to 55 mass%, the monofunctional acrylate (II) is 20 to 55 mass%, It is preferable to contain 20 to 55 mass% of other (meth) acrylate compounds other than the two and a radical polymerization initiator in a proportion of 1 to 10 mass%, and 20 to 50 mass% of the urethanized acrylic compound (I). The monofunctional acrylate (II) is contained in an amount of 20 to 50% by mass, other (meth) acrylate compounds other than the above two are contained in an amount of 20 to 50% by mass and a radical polymerization initiator is contained in a proportion of 2 to 7% by mass. More preferable .
If the proportion of each component is out of the above range, it will be difficult to achieve a reduction in shrinkage during curing, or the viscosity of the photocurable resin will become too high to be suitable for use in optical modeling, etc. It becomes easy to produce the fall of the physical property of photocured materials, such as a sensitivity fall and the optical three-dimensional molded article obtained.

Moreover, when the photocurable resin composition of the present invention contains a tertiary amino group-containing acrylate compound (III) as a part of another (meth) acrylate compound, the total mass of the photocurable resin composition The tertiary amino group-containing acrylate compound (III) is preferably contained in a proportion of 0.1 to 10% by mass, more preferably in a proportion of 0.2 to 5% by mass. More preferably, it is contained in a proportion of 5 to 3% by mass.
By setting the content of the tertiary amino group-containing acrylate compound (III) within the above range, it is possible to achieve further improvement in curing sensitivity while reducing the shrinkage rate during photocuring.

  The photocurable resin composition of the present invention may contain a radical polymerizable compound other than those described above, for example, morpholinoacrylamide, dimethylacrylamide, maleimide acrylate, etc., as necessary, as long as the effects of the present invention are not impaired. Good. In addition, the photocurable resin composition of the present invention includes, if necessary, colorants such as pigments and dyes, antifoaming agents, leveling agents, thickeners, flame retardants, antioxidants, fillers (crosslinked polymer particles). , Silica, glass powder, ceramic powder, metal powder, etc.), and a suitable amount of one or more kinds such as modifying resins.

The method for preparing the photocurable resin composition of the present invention is not particularly limited, and urethanized acrylic compound (I), monofunctional acrylate (II), other (meth) acrylate compounds and radical polymerization initiator are uniformly mixed. Any method may be used as long as the prepared composition can be prepared.
For example, (i) a pre-manufactured urethanized acrylic compound (I), monofunctional acrylate (II) and other (meth) acrylate compounds are mixed at a predetermined ratio, and then a radical polymerization initiator is mixed with the mixture. And (ii) urethanization in the presence of the diluent using all of the monofunctional acrylate (II) and other (meth) acrylate compounds as diluents A method of preparing a photocurable resin composition by mixing a radical polymerization initiator after synthesizing an acrylic compound (I), (iii) a monofunctional acrylate (II) and / or other (meth) acrylate-based compound After synthesizing urethanized acrylic compound (I) in the presence of the diluent using a part of the diluent, the remaining monofunctional acrylate Method of preparing a photo-curable resin composition by mixing II) and / or other (meth) acrylate compound and a radical polymerization initiator, or the like can be adopted.

For optically three-dimensional modeling using the photocurable resin composition of the present invention, any conventionally known optical three-dimensional modeling method and apparatus can be used. As a representative example of the optical three-dimensional modeling method that can be preferably employed, active energy rays are selectively irradiated so that a cured layer having a desired pattern is obtained in the liquid photocurable resin composition of the present invention. Lamination operation of forming a cured layer and then supplying an uncured liquid photocurable resin composition to the cured layer and irradiating the same with active energy rays to form a cured layer continuous with the cured layer. The method of finally obtaining the target three-dimensional molded item by repeating can be mentioned.
Examples of the active energy rays at that time include ultraviolet rays, electron beams, X-rays, radiation, and high frequencies as described above. Among them, ultraviolet rays having a wavelength of 300 to 400 nm are preferably used from an economical viewpoint. As a light source at that time, an ultraviolet laser (for example, a semiconductor-excited solid laser, an Ar laser, a He—Cd laser, etc.), a high-pressure mercury lamp Ultra high pressure mercury lamps, mercury lamps, xenon lamps, halogen lamps, metal halide lamps, ultraviolet LEDs (light emitting diodes), fluorescent lamps, and the like can be used.

In forming each cured resin layer having a predetermined shape pattern by irradiating the modeling surface made of the photocurable resin composition with active energy rays, the active energy rays narrowed to a point like a laser beam are used. It may be used to form a cured resin layer in a stippling or line drawing system, or through a planar drawing mask formed by arranging a plurality of micro light shutters such as a liquid crystal shutter or a digital micromirror shutter (DMD). Alternatively, a modeling method may be employed in which the modeling surface is irradiated with active energy rays in a planar shape to form a cured resin layer.
Among them, the photocurable resin composition of the present invention has a low shrinkage rate at the time of curing and high curing sensitivity, so that it has a higher energy intensity than laser light such as a high-pressure mercury lamp and an ultrahigh-pressure mercury lamp. It is suitably used for an optical three-dimensional modeling method in which a modeling surface is irradiated with light through a planar drawing mask using a small light source.

The photocurable resin composition of the present invention can be widely used in the field of optical three-dimensional modeling, and is not limited at all, but as a typical application field, in order to verify the appearance design in the middle of the design Model, a model for checking the functionality of parts, a resin mold for producing a mold, a base model for producing a mold, a direct mold for a prototype mold, and the like. In particular, the photo-curable resin composition of the present invention can exert its power in creating a precise part model. More specifically, for example, it can be effectively used for applications such as precision parts, electrical / electronic parts, furniture, building structures, automotive parts, various containers, castings, models, mother dies, processing, etc. .
Furthermore, if necessary, the photocurable resin composition of the present invention can be used for applications such as optical fiber coating and optical disk coating in addition to optical three-dimensional modeling.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. In the following examples, “parts” means parts by mass.
In the following examples, the viscosity, depth of cure (Dp), critical cure energy (Ec) and work cure energy (E ₁₀ ) of the photocurable resin composition are measured, evaluated for stability, and obtained by optical modeling. The measurement or calculation of the mechanical properties [tensile properties (breaking strength, breaking elongation, tensile elastic modulus), yield strength, bending properties (bending strength, bending elastic modulus)] and shrinkage of This was done as follows.

(1) Viscosity of photocurable resin composition:
After putting a photocurable resin composition in a 25 degreeC thermostat and adjusting the temperature of a photocurable resin composition to 25 degreeC, it measured using the B-type viscosity meter (made by Tokyo Keiki Co., Ltd.).

(2) Curing depth (Dp), critical curing energy (Ec) and work curing energy (E ₁₀ ) of the photocurable resin composition:
Measurement was performed according to the theory described in Non-Patent Document 1. Specifically, a modeling surface (liquid surface) made of a photocurable resin composition is irradiated with light from an ultrahigh pressure mercury lamp (ultraviolet light in a wavelength range of 340 to 380 nm, energy intensity ² mW / cm ² ). A photo-cured film corresponding to the layer was formed. By changing the light irradiation time at the time of forming the cured film between 1 to 5 seconds, for example, 1 second, 2 seconds, 3 seconds, 4 seconds, and 5 seconds, this operation is performed on the modeling surface. The amount of irradiation energy was changed, the photocured film produced by each amount of irradiation energy was taken out from the photocurable resin composition liquid, the uncured resin was removed, the thickness of each cured film was measured with a constant pressure caliper, and the photocured film Is plotted with the Y-axis and the irradiation energy amount as the X-axis, and the cure depth is obtained from the slope of the straight line obtained by plotting, and the intercept of the X-axis is defined as the critical cure energy [Ec (mJ / cm ² )]. The amount of exposure energy required for curing to a thickness of 0.25 mm was defined as work curing energy (E ₁₀ / mJ / cm ² ).

(3) Stability of the photocurable resin composition;
The photocurable resin composition is placed in a constant temperature bath at a temperature of 80 ° C. in a dark place in an air atmosphere and stored for 28 days. During this period, the state is visually observed every day, and the presence or absence of dust and gelation are observed. The presence or absence of was investigated.

(4) Tensile properties of the optically shaped article (breaking strength, breaking elongation, tensile modulus):
Using the optical modeling thing (the dumbbell-shaped test piece based on JIS K-7113) produced in the following examples or comparative examples, the breaking strength (tensile strength) and breaking elongation of the test piece according to JIS K-7113 The degree (tensile elongation) and tensile modulus were measured.

(5) Yield strength of stereolithography:
In the tensile property test of (4) above, the strength at the point where the optically shaped article moves from elasticity to plasticity was taken as the yield strength.

(6) Bending characteristics (bending strength, flexural modulus) of stereolithography:
The bending strength and the flexural modulus of the test piece were measured according to JIS K-7171 using the optically shaped article (bar-shaped test piece conforming to JIS K-7171) produced in the following examples or comparative examples. .

(7) Shrinkage rate:
From the specific gravity (d ₀ ) of the photo-curable resin composition (liquid) before photo-curing and the specific gravity (d ₁ ) of the photo-cured product obtained by photo-curing, the shrinkage rate was determined by the following formula.

Shrinkage rate (%) = {(d ₁ −d ₀ ) / d ₁ } × 100

<< Synthesis Example 1 >> [Synthesis of tertiary amino group-containing acrylate compound (IIIa)]
In Synthesis Example 1, a tertiary amino group-containing acrylate compound having the following chemical formula [hereinafter referred to as “tertiary amino group-containing acrylate compound (IIIa)”] was synthesized.

That is, 100 g of tricyclodecane dimethanol diacrylate (“A-DCP” manufactured by Shin-Nakamura Chemical Co., Ltd.) is placed in a 1-liter three-necked flask, and 12 g of diethylamine is maintained at an internal temperature of 50 to 60 ° C. of the flask. The solution was added dropwise over 1 hour. After completion of the dropwise addition, the reaction was carried out at the same temperature until the absorption peak at 3300 cm ⁻¹ disappeared in the infrared absorption spectrum to produce a tertiary amino group-containing acrylate compound (IIIa).
The infrared absorption spectrum (IR spectrum) of the tertiary amino group-containing acrylate compound (IIIa) obtained in this way was measured using NaCl with an infrared analyzer (“FTIR-8100M type spectrometer” manufactured by Shimadzu Corporation). When measured, it was as shown in FIG.

Example 1
(1) (i) Acrylic acid dimer (“Aronix M-5600” manufactured by Toagosei Co., Ltd.) 187.2 g (1.3 mol) and 142 g of glycidyl methacrylate were placed in a four-necked flask, 33 g of triethylamine as a catalyst, polymerization prohibited 0.28 g of methylhydroquinone was added as an agent, and the mixture was reacted at 80 to 85 ° C. with stirring for 5 hours. Next, 420 g of toluene was added, and then washed with 88 g of a 15% aqueous sodium hydroxide solution, and then further washed with 100 ml of water. Next, washing was performed with 300 ml of 1N hydrochloric acid, and then washing was repeated using 100 ml of water for one washing until neutral. Next, the toluene solution after the washing treatment was dried using sodium sulfate, and then toluene was removed under reduced pressure to obtain a (meth) acrylate compound of glycerin represented by the following chemical formula.

(Ii) An oil prepared by charging 177.6 g of isophorone diisocyanate, 205.6 g of morpholinoacrylamide and 0.48 g of dibutyltin dilaurate into a 1-liter three-necked flask equipped with a stirrer, temperature controller, thermometer and condenser. The mixture was heated with a bath so that the internal temperature was 80 to 90 ° C., and stirred until it was completely dissolved.
(Iii) Dropping with a side tube in which a solution obtained by uniformly mixing and dissolving 0.48 g of methylhydroquinone in 288.8 g of the (meth) acrylate compound of glycerin obtained in (i) above was kept at 50 ° C. in advance. The funnel was charged, and the liquid in the dropping funnel was added dropwise to the contents of (ii) above with stirring while maintaining the temperature of the flask contents at 80 to 90 ° C. in a nitrogen atmosphere. Stir for hours.
(Iv) Next, after the temperature of the flask contents was lowered to 60 ° C., 4 mol of propylene oxide adduct of pentaerythritol charged in another dropping funnel (1 mol of propylene oxide was added to each of 4 hydroxyl groups of pentaerythritol) 73.2 g was quickly added dropwise and reacted for 4 hours while maintaining the temperature of the flask contents at 80 to 90 ° C. to contain the urethanized acrylic compound (Ia) and the radical polymerizable compound (morpholinoacrylamide). The reaction product was produced and the reaction product obtained was removed from the flask while warm.
(V) The resulting reaction product was colorless and exhibited a viscous liquid at room temperature (25 ° C.). The urethanized acrylic compound (Ia) contained in the reaction product obtained here has d = 2, two R ¹ = hydrogen atom and methyl group, and A = glycenline in the above general formula (I) It is a urethanized acrylic compound having a residue, e = 1, D = isophorone group, G = propylene oxide group (h = 1), and f = 4.

(2) A reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide obtained in (1) above in a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a cooling tube and a dropping funnel with side tubes. 500 g, 100 g of lauryl acrylate, 200 g of isobornyl acrylate, and 300 g of tricyclodecane dimethanol diacrylate were charged, followed by vacuum deaeration and nitrogen replacement. Next, 50 g of 2,2-dimethoxy-1,2-diphenylethane-1-one (“Irgacure 651” manufactured by Ciba Geigy Co., Ltd .; radical photopolymerization initiator) is added and completely dissolved in an environment where ultraviolet rays are blocked. Then, the mixture was stirred at a temperature of 25 ° C. (mixing stirring time: about 6 hours) to obtain a photocurable resin composition [viscosity: 500 mPa · s (25 ° C.)] as a colorless and transparent viscous liquid. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ia): lauryl acrylate [monofunctional acrylate (II)]: isobornyl acrylate [monofunctional acrylate (II)]: tricyclode The mass ratio of candimethanol diacrylate [other (meth) acrylate-based compound]: morpholinoacrylamide: radical polymerization initiator was 35: 10: 20: 30: 15: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 1 below.

(4) Stereolithography apparatus (Seamet Co., Ltd.) equipped with an ultra-high pressure mercury lamp (120 W, manufactured by Iwasaki Electric Co., Ltd.) as a light source and a TFT VGA (640 × 480 pixels) liquid crystal manufactured by Epson as a planar drawing mask "LE3000" manufactured) and using the photocurable resin composition obtained in (2) above, the projection size on the modeling surface (the surface of the photocurable resin composition) = 35 mm (advancing direction of the apparatus) ) X 47 mm (perpendicular to the direction of travel) (square), about 7 mm with a light source, a condensing lens, a planar drawing mask, and a projection lens integrated under the condition of a light energy intensity of ² mW / cm ^{2 on} the modeling surface The image of the planar drawing mask is moved in accordance with the cross-sectional shape pattern to be formed at the speed of / sec. While continuously changing the image pattern in a moving image, light irradiation is performed at a thickness of 0.1 mm, and a dumbbell-shaped three-dimensional object conforming to JIS K-7113 for measuring tensile properties and bending properties is measured. A bar-shaped three-dimensionally shaped article conforming to JIS K-7171 was produced. In this stereolithography operation, the irradiation time in each part of the photocured layer was 5 seconds, and the light irradiation amount in each part was 8 to 15 mJ. Table 1 below shows the tensile properties and bending properties of the obtained test pieces based on JIS K-7113 and JIS K-7171.

Example 2
(1) The same operation as (1) of Example 1 was performed to prepare a reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide in a mass ratio of the former: the latter = 35: 15.
(2) A reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide obtained in (1) above in a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a cooling tube and a dropping funnel with side tubes. 500 g, 300 g of isobornyl acrylate and 200 g of tricyclodecane dimethanol diacrylate were charged, and vacuum deaeration and nitrogen substitution were performed. Next, 50 g of the same radical polymerization initiator as used in (2) of Example 1 was added in an environment where ultraviolet rays were blocked, and the mixture was stirred at a temperature of 25 ° C. until it was completely dissolved (mixing and stirring time of about 6 hours), a photo-curable resin composition [viscosity 566 mPa · s (25 ° C.)] which was a colorless transparent viscous liquid was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ia): isobornyl acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) acrylates. The mass ratio of the system compound]: morpholinoacrylamide: radical polymerization initiator was 35: 30: 20: 15: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 1 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 1 below.

Example 3
(1) The same operation as (1) of Example 1 was performed to prepare a reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide at a mass ratio of the former: the latter = 35: 15.
(2) A reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide obtained in (1) above in a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a cooling tube and a dropping funnel with side tubes. 500 g, 300 g of dicyclopentanyl acrylate and 200 g of tricyclodecane dimethanol diacrylate were charged, and vacuum deaeration and nitrogen substitution were performed. Next, 50 g of the same radical polymerization initiator as used in (2) of Example 1 was added in an environment where ultraviolet rays were blocked, and the mixture was stirred at a temperature of 25 ° C. until it was completely dissolved (mixing and stirring time of about 6 hours), a photocurable resin composition [viscosity 762 mPa · s (25 ° C.)] which was a colorless and transparent viscous liquid was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ia): dicyclopentanyl acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) The mass ratio of acrylate compound]: morpholinoacrylamide: radical polymerization initiator was 35: 30: 20: 15: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 1 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 1 below.

<< Comparative Example 1 >>
(1) The same operation as (1) of Example 1 was performed to prepare a reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide at a mass ratio of the former: the latter = 35: 15.
(2) A reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide obtained in (1) above in a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a cooling tube and a dropping funnel with side tubes. 500 g, 200 g of tricyclodecane dimethanol diacrylate and 300 g of morpholinoacrylamide were charged, and vacuum deaeration and nitrogen substitution were performed. Next, 50 g of the same radical polymerization initiator as used in (2) of Example 1 was added in an environment where ultraviolet rays were blocked, and the mixture was stirred at a temperature of 25 ° C. until it was completely dissolved (mixing and stirring time of about 6 hours), a photocurable resin composition [viscosity 570 mPa · s (25 ° C.)] which was a colorless and transparent viscous liquid was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ia): morpholinoacrylamide (other radical polymerizable compound): tricyclodecane dimethanol diacrylate [other (meth) acrylate compounds ]: The mass ratio of the radical polymerization initiator was 35: 45: 20: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 1 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 1 below.

<< Comparative Example 2 >>
(1) The same operation as (1) of Example 1 was performed to prepare a reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide at a mass ratio of the former: the latter = 35: 15.
(2) A reaction product containing the urethanized acrylic compound (Ia) and morpholinoacrylamide obtained in (1) above in a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a cooling tube and a dropping funnel with side tubes. 500 g, 200 g of tricyclodecane dimethanol diacrylate, and 300 g of 1,9-nonanediol diacrylate were charged, followed by vacuum deaeration and nitrogen replacement. Next, 50 g of the same radical polymerization initiator as used in (2) of Example 1 was added in an environment where ultraviolet rays were blocked, and the mixture was stirred at a temperature of 25 ° C. until it was completely dissolved (mixing and stirring time of about 6 hours), a photocurable resin composition [viscosity 290 mPa · s (25 ° C.)], which was a colorless transparent viscous liquid, was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ia): 1,9-nonanediol diacrylate [bifunctional acrylate, other (meth) acrylate compounds]: tricyclodecanedi. The mass ratio of methanol diacrylate [bifunctional acrylate, other (meth) acrylate compounds]: morpholinoacrylamide: radical polymerization initiator was 35: 30: 20: 15: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 1 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 1 below.

  As seen in the results of Table 1 above, the photocurability of Examples 1 to 3 containing a urethanized acrylic compound (I), a monofunctional acrylate (II), another (meth) acrylate compound and a radical polymerization initiator. The resin composition is a photocurable resin composition of Comparative Examples 1 and 2 which contains a urethanized acrylic compound (I), another (meth) acrylate compound and a radical polymerization initiator and does not contain a monofunctional acrylate (II). In comparison, the shrinkage during curing is greatly reduced.

Example 4
(1) (i) In a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a temperature controller, a thermometer, and a condenser, 177.6 g of isophorone diisocyanate, 147.3 g of tricyclodecane dimethanol diacrylate and dibutyltin 0.34 g of dilaurate was charged and heated in an oil bath so that the internal temperature became 70-80 ° C.
(Ii) A solution prepared by uniformly mixing and dissolving 0.34 g of methylhydroquinone in 42.8 g of 2-hydroxyethyl acrylate was charged into a dropping funnel with a side tube that had been kept warm at 50 ° C., and the liquid in the dropping funnel Was added dropwise to the contents in the flask of (1) above with stirring while maintaining the temperature of the contents of the flask at 80 to 90 ° C. in a nitrogen atmosphere, and stirred at the same temperature for 2 hours to cause a reaction. .
(Iii) Next, after the temperature of the flask contents was lowered to 60 ° C., 4 mol of propylene oxide adduct of pentaerythritol charged in another dropping funnel (1 mol of propylene oxide was added to each of 4 hydroxyl groups of pentaerythritol) 73.2 g was quickly added dropwise, and the flask was allowed to react for 4 hours while maintaining the temperature of the flask at 80 to 90 ° C., and urethanized acrylic compound (Ib) and tricyclodecane dimethanol diacrylate [others] A reaction product containing (meth) acrylate compound; also used as a diluent] in a ratio of 35:20 parts by mass was produced, and the obtained reaction product was taken out of the flask while it was warm.
(Iv) The resulting reaction product was colorless and exhibited a viscous liquid at room temperature (25 ° C.). The urethanized acrylic compound (Ib) contained in the reaction product obtained here has the following formula (I): d = 1, one R ¹ = hydrogen atom, A = ethylene group, e = 1, D = isophorone group, G = propylene oxide group (h = 1), f = 4.

(2) Urethane acrylic compound (Ib) obtained in (1) above and tricyclodecane dimethanol diacrylate in a three-necked flask with an internal volume of 5 liters equipped with a stirrer, a condenser tube and a dropping funnel with side tubes. The reaction product containing 550 g and 450 g of isobornyl acrylate were charged and purged with nitrogen under reduced pressure. Next, 50 g of the same radical photopolymerization initiator (“Irgacure 651” manufactured by Ciba Geigy Co., Ltd.) used in Example 1 was added in an environment where ultraviolet rays were blocked, and mixed and stirred at a temperature of 25 ° C. until completely dissolved. (Mixing and stirring time: about 6 hours) to obtain a photocurable resin composition [viscosity 732 mPa · s (25 ° C.)] which is a colorless and transparent viscous liquid. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ib): isobornyl acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) acrylates. The mass ratio of the system compound]: radical polymerization initiator was 35: 45: 20: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 2 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 2 below.

Example 5
(1) A reaction product containing the urethane-modified acrylic compound (Ib) and tricyclodecane dimethanol diacrylate at a mass ratio of the former: the latter = 35: 20 by performing the same operation as (1) of Example 4. Was prepared.
(2) Urethane acrylic compound (Ib) obtained in (1) above and tricyclodecane dimethanol diacrylate in a three-necked flask with an internal volume of 5 liters equipped with a stirrer, a condenser tube and a dropping funnel with side tubes. The reaction product containing 550 g, 450 g of isobornyl acrylate and 10 g of the tertiary amino group-containing acrylate compound (IIIa) produced in Synthesis Example 1 were charged, and vacuum deaeration and nitrogen substitution were performed. Next, 50 g of the same radical polymerization initiator as used in (2) of Example 1 was added in an environment where ultraviolet rays were blocked, and the mixture was stirred at a temperature of 25 ° C. until it was completely dissolved (mixing and stirring time of about 6 hours), a photocurable resin composition [viscosity 774 mPa · s (25 ° C.)], which is a colorless and transparent viscous liquid, was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ib): isobornyl acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) acrylates. Series compound]: tertiary amino group-containing acrylate compound (IIIa) [other (meth) acrylate compound]: The mass ratio of the radical polymerization initiator was 35: 45: 20: 1: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 2 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 2 below.

Example 6
(1) In Example 5, instead of using Irgacure 651 as a radical polymerization initiator, 30 g of Irgacure 651 and 2,4,6-trimethylbenzoyl-diphenylformyne oxide (Ciba Specialty Chemicals) A photocurable resin composition [viscosity of 778 mPa · s], which is a colorless and transparent viscous liquid, by performing the same operations as in (1) and (5) of Example 5 except that 20 g of “Tarocur TPO” manufactured by the company is used. s (25 ° C.)]. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ib): isobornyl acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) acrylates. -Based compound]: tertiary amino group-containing acrylate compound (IIIa) [other (meth) acrylate-based compound]: Irgacure 651: Tarocure The mass ratio of TPO was 35: 45: 20: 1: 3: 2. .
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 2 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 2 below.

Example 7
(1) A reaction product containing the urethane-modified acrylic compound (Ib) and tricyclodecane dimethanol diacrylate at a mass ratio of the former: the latter = 35: 20 by performing the same operation as (1) of Example 4. Was prepared.
(2) Urethane acrylic compound (Ib) obtained in (1) above and tricyclodecane dimethanol diacrylate in a three-necked flask with an internal volume of 5 liters equipped with a stirrer, a condenser tube and a dropping funnel with side tubes. The reaction product containing 550 g, 450 g of tricyclodecane methanol acrylate (“A-TCM” manufactured by Shin-Nakamura Chemical Co., Ltd.) and 10 g of the tertiary amino group-containing acrylate compound (IIIa) produced in Synthesis Example 1 were charged under reduced pressure. The atmosphere was replaced with nitrogen. Next, under an environment where ultraviolet rays are blocked, 30 g of the same radical polymerization initiator (Irgacure 651) used in (2) of Example 1 and 20 g of Tarocur TPO are added, and the temperature is 25 ° C. until it is completely dissolved. After mixing and stirring (mixing and stirring time of about 6 hours), a photocurable resin composition [viscosity 1062 mPa · s (25 ° C.)], which is a colorless and transparent viscous liquid, was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ib): tricyclodecane methanol acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) Acrylate compound]: tertiary amino group-containing acrylate compound (IIIa) [other (meth) acrylate compound]: The mass ratio of the radical polymerization initiator was 35: 45: 20: 1: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 2 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 2 below.

Example 8
(1) A reaction product containing the urethane-modified acrylic compound (Ib) and tricyclodecane dimethanol diacrylate at a mass ratio of the former: the latter = 35: 20 by performing the same operation as (1) of Example 4. Was prepared.
(2) Urethane acrylic compound (Ib) obtained in (1) above and tricyclodecane dimethanol diacrylate in a three-necked flask with an internal volume of 5 liters equipped with a stirrer, a condenser tube and a dropping funnel with side tubes. The reaction product containing 550 g, 450 g of dicyclopentanyl acrylate (“FA-513A” manufactured by Hitachi Chemical Co., Ltd.) and 30 g of the tertiary amino group-containing acrylate compound (IIIa) produced in Synthesis Example 1 were charged and degassed under reduced pressure. Replaced with nitrogen. Next, in an environment where ultraviolet rays are blocked, 30 g of Irgacure 651 and 20 g of Tarocur TPO are added, and the mixture is stirred at a temperature of 25 ° C. until it is completely dissolved (mixing stirring time is about 6 hours). A photocurable resin composition [viscosity 1056 mPa · s (25 ° C.)] was obtained. The composition of the photocurable resin composition thus obtained was urethanized acrylic compound (Ib): dicyclopentanyl acrylate [monofunctional acrylate (II)]: tricyclodecane dimethanol diacrylate [other (meth) Acrylate compound]: tertiary amino group-containing acrylate compound (IIIa) [other (meth) acrylate compound]: The mass ratio of the radical polymerization initiator was 35: 45: 20: 1: 5.
(3) The curing depth (Dp), critical curing energy (Ec), work curing energy (E ₁₀ ) and stability of the photocurable resin composition obtained in the above (2) were measured or evaluated by the methods described above. However, it was as shown in Table 2 below.
(4) Using each photocurable resin composition obtained in (2) above, optical three-dimensional modeling is performed in the same manner as in (4) of Example 1, and dumbbells conforming to JIS K-7113 are performed. The bar-shaped test piece based on the shape test piece and JIS K-7171 was produced, and the physical properties were measured by the method described above. The results are shown in Table 2 below.

  As seen from the results in Table 2 above, the photocurable resin compositions of Examples 4 to 8 all have a low shrinkage rate in the 5% range when cured.

  The photocurable resin composition of the present invention is low in viscosity and excellent in handleability at the time of optical modeling, and has excellent storage stability without significant increase in viscosity or gelation even when stored for a long period of time. 3D objects can be manufactured with high modeling accuracy and high dimensional accuracy with small shrinkage and high curing sensitivity, and cured in a short time by irradiation with active energy rays to produce 3D objects with high productivity. Moreover, it is excellent in the mechanical characteristic of the three-dimensional molded item obtained in addition. Therefore, using the photocurable resin composition of the present invention, models for precision parts, electrical / electronic parts, furniture, building structures, automotive parts, various containers, castings, molds, mother molds, etc. High modeling speed and dimensions for machining models, parts for designing complex heat transfer circuits, parts for analysis planning of heat transfer behavior of complex structures, and other three-dimensional objects with complicated shapes and structures It can be obtained smoothly with accuracy.

It is a figure which shows IR spectrum of the tertiary amino group containing acrylate compound (IIIa) obtained by the synthesis example 1.

Claims (4)

(I) the following general formula (I);

{Wherein R ¹ is a hydrogen atom or a methyl group, d is 1 or 2, and when d is 2, one or both R ¹ is a methyl group, A is a diol or triol residue, D is divalent or trivalent unsubstituted or substituted hydrocarbon radical, G is represented by the formula _{:-( CH 2 CH 2 O) g-} (g wherein is an integer of 1 to 4) (poly) Ethylene oxide group, (poly) propylene oxide group represented by the formula:-[(CH ₂ CH (CH ₃ ) O] h- (where h represents an integer of 1 to 4) or formula:-(CH ₂ represented by _{CH 2 O) j [(CH} 2 CH (CH 3) O] k- ( sum of an integer of each j and k in the formula 1 to 3 j and k is 2 to 4) (poly) ethylene oxide-propylene oxide group, R ² is a hydrogen atom or an alkyl group, e is 1 or 2, and f Or an 4.}
At least one of urethanized acrylic compounds (I) represented by:
(Ii) the following general formula (II);

(In the formula, R ³ represents a monovalent hydrocarbon group having 5 to 20 carbon atoms.)
A monofunctional acrylate (II) represented by:
(Iii) (meth) acrylate compounds other than the urethanized acrylic compound (I) and the monofunctional acrylate (II); and
(Iv) an active energy ray sensitive radical polymerization initiator;
A photocurable resin composition comprising:
As a part of other (meth) acrylate compounds other than the urethanized acrylic compound (I) and the monofunctional acrylate (II), the following general formula (III);

[Wherein, R ⁴ and R ⁵ represent the same or different alkyl group or aralkyl group, R ⁶ represents an (m + n) -valent acrylate residue, and m and n are each independently an integer of 1 to 5 And m + n is 2-6. ]
A photocurable resin comprising a tertiary amino group-containing acrylate compound (III) represented by formula (III) in a proportion of 0.1 to 10% by mass based on the total mass of the photocurable resin composition. Composition.   Based on the total mass of the photocurable resin composition, the urethanized acrylic compound (I) is 20 to 55% by mass, the monofunctional acrylate (II) is 20 to 55% by mass, and other (meta) other than the above two. The photocurable resin composition according to claim 1, comprising 20 to 55% by mass of an acrylate compound and 1 to 10% by mass of an active energy ray-sensitive radical polymerization initiator. The photocurable resin composition according to claim 1 or 2 which is for stereolithography. The method of manufacturing a three-dimensional molded item by performing optical three-dimensional modeling using the photocurable resin composition of any one of Claims 1-3 .

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