JPH08290477A - Composition for optical solid shaping - Google Patents

Abstract

PURPOSE: To improve the mechanical physical properties and shape accuracy of a solid structure by using an unsaturated ester monourethane of a specified structure formed by using two kinds of polymerizable groups and a specified vinyl monomer based on the weight ratio respectively. CONSTITUTION: A composition for optical solid shaping containing an unsaturated ester monourethane is constituted of an unsaturated ester monourethane represented by the formula and a vinyl monomer composed of a mixture of an acrylic morpholide or (meth)acrylic morpholide and dial(meth)acrylate. A mixture is prepared by mixing and melting at the ratio of the unsaturated ester monourethane/vinyl monomer=100/25-100/150 (weight ratio). In the formula, X represents a residual group formed by removing a hydroxyl group from a trivalent alcohol, R1 represents H or CH3 , R2 represents a 2-6C alkylene group. Good mechanical properties and thermal properties are demonstrated by the arrangement to improve shape accuracy.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition for optical three-dimensional modeling. The NC cutting method has been used for the production of various models and fixed objects such as a model for mold making, a model for copying, and a model for die-sinking electric discharge machining. In recent years, these have photopolymerizability. Attention has been focused on an optical three-dimensional modeling method in which a composition for optical three-dimensional modeling is irradiated with energy rays to cure and mold a predetermined three-dimensional model. The present invention relates to an optical stereoscopic molding composition applied to the above-described optical stereoscopic molding method, and more particularly to an optical stereoscopic molding composition containing an unsaturated ester monourethane.

[0002]

2. Description of the Related Art Conventionally, as a composition for optical three-dimensional modeling containing an unsaturated ester urethane, (mol) (meth) acrylic acid partial ester of a polyol having one free hydroxyl group in the molecule and an n-valent poly (n) are used. Example containing unsaturated ester polyurethane obtained from 1 mol of isocyanate compound (JP-A-2-145616, JP-A-1-20491)
5, JP-A-63-35550, JP-A-61-276686
3, JP-A-63-112551, JP-B-63-2020
3), Unsaturation obtained from 1 mol of a partial ester obtained from triol or tetraol and (meth) acrylic acid and having one free hydroxyl group in the molecule, and 1 mol of isocyanatoalkyl (meth) acrylate There is an example containing an ester monourethane (JP-A-4-53809).

However, the conventional optical three-dimensional modeling composition containing the above unsaturated ester urethane is
There are drawbacks that the obtained three-dimensional molded article has poor physical properties, especially mechanical properties, and poor shape accuracy. As a cause of deteriorating the shape accuracy of the obtained three-dimensional model, the volume change in the process of curing the optical three-dimensional model composition, the heterogeneity of the material in the optical three-dimensional model composition, the desired three-dimensional model There is a shape of the modeled object, etc., and when these are combined, a non-uniform strain stress is generated inside the three-dimensional modeled object, and when such strain stress is concentrated on a specific portion or a specific direction of the three-dimensional modeled object,
Deformation such as warping, twisting, and crushing occurs, and structural destruction such as cracking and peeling occurs. In addition, such a three-dimensional molded article having inherent strain stress is potentially unstable in shape, and is likely to be deformed or structurally destroyed over time due to temperature conditions, use with load, or the like. In general, a three-dimensional object obtained from a composition for optical three-dimensional object having a low glass transition temperature or elastic modulus and a high tensile elongation is likely to be deformed, and has a high glass transition temperature and a low tensile elongation. Is prone to structural destruction.

[0004] Conventionally, attempts have been made to improve the physical properties of the obtained three-dimensional model, especially the thermal physical properties. This includes, for example, 1) an example in which the ethylenic double bond concentration is increased in the composition for optical three-dimensional modeling for the purpose of increasing the cross-linking density of the three-dimensional model, and 2) the polymerizable group There is an example in which both an acrylate group and a methacrylate group are contained (JP-A-6-199962). But,
In these conventional examples, the volumetric shrinkage due to photocuring is rather increased, and the shape accuracy of the obtained three-dimensional molded item is further deteriorated. Further, in these conventional examples, the mechanical properties of the obtained three-dimensional model, particularly the tensile elongation is low, and as a result, the toughness value represented by the product of the tensile elongation and the tensile strength is commonly used as a plastic molding material. Thermoplastic resin such as ABS
The toughness value of the three-dimensional model obtained from the resin is remarkably inferior, and thus the three-dimensional model obtained can be used only in limited applications.

[0005]

The problem to be solved by the present invention is that, in the conventional optical three-dimensional modeling composition, the physical properties of the obtained three-dimensional molded product, especially the mechanical properties are poor, and the shape accuracy is low. That's a bad point.

[0006]

However, the present inventors have
Regarding an optical stereolithography composition containing an unsaturated ester urethane, the unsaturated ester monourethane obtained from a di (meth) acrylate of a trihydric alcohol and an isocyanatoalkyl (meth) acrylate is noticed. As a result of studying the relationship between the chemical structure of monourethane and vinyl monomer used in combination with the shape precision, thermal properties and mechanical properties of the obtained three-dimensional model, both acryloyl group and methacryloyl group were identified as the polymerizable groups. Have,
In addition, an unsaturated ester monourethane having a specific structure in which these two kinds of polymerizable groups are bonded to a urethane group in a specific manner and a specific vinyl monomer containing (meth) acrylic acid morpholide are each in a predetermined ratio. It has been found that it is correct and suitable to use.

That is, the present invention comprises an unsaturated ester monourethane represented by the following formula 1 and the following vinyl monomer, wherein the unsaturated ester monourethane / the vinyl monomer = 100/25 to 100 / The present invention relates to a composition for optical stereolithography, which is characterized by comprising a ratio of 150 (weight ratio).

[0008]

(Equation 1)

(In the formula 1, X: a residue obtained by removing a hydroxyl group from a trihydric alcohol R ¹ : H or CH ₃ R ² : an alkylene group having 2 to 6 carbon atoms)

Vinyl monomer: (meth) acrylic acid morpholide or a mixture of (meth) acrylic acid morpholide and diol di (meth) acrylate.

The unsaturated ester monourethane represented by the formula 1 includes 1) a reaction product of a diacrylate of a trihydric alcohol / methacryloyloxyalkyl isocyanate = 1/1 (molar ratio), and 2) a monoacrylate of a trihydric alcohol. The reaction product of monomethacrylate / methacryloyloxyalkyl isocyanate = 1/1 (molar ratio) is included.

Examples of diacrylates or monoacrylates / monomethacrylates of trihydric alcohols include glycerin, trimethylolpropane, and 5-methyl-1,2,4.
Examples thereof include diacrylates or monoacrylate monomethacrylates of trihydric alcohols such as heptanetriol and 1,2,6-hexanetriol. Of these, glycerin diacrylate and glycerin monoacrylate monomethacrylate can be advantageously used.

Examples of methacryloyloxyalkyl isocyanates to be reacted with diacrylate of monohydric alcohol or monoacrylate / monomethacrylate include methacryloyloxyethyl isocyanate, methacryloyloxypropyl isocyanate, methacryloyloxy-2-methylethyl isocyanate and methacryloyloxyhexyl isocyanate. Among these, methacryloyloxyethyl isocyanate and methacryloyloxypropyl isocyanate can be advantageously used.

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

According to the present invention, among the polymerizable groups contained in the unsaturated ester monourethane represented by the formula 1, the methacryloyl group derived from isocyanatoalkylmethacrylate and the acryloyl group derived from acrylate of trihydric alcohol are Both have a high photopolymerization activity, and conversely, a methacryloyl group derived from a methacrylate of a trihydric alcohol has a property of a low photopolymerization activity. The composition for optical stereolithography using an unsaturated ester monourethane in which the number of polymerizable groups having a large photopolymerization activity in the molecule is less than 2 on average, because sufficient cross-linking is not formed in photopolymerization. The three-dimensional model obtained from the optical three-dimensional model composition has poor mechanical properties and thermal properties. An unsaturated ester monourethane in which all three polymerizable groups are acryloyl groups has a very high photopolymerization activity by itself, but a three-dimensional object obtained from an optical three-dimensional composition composition using the same. Has poor thermal properties. Therefore, in the present invention, in order to impart excellent mechanical properties and thermal properties to the obtained three-dimensional molded article, an acryloyl group originally having a large photopolymerization activity and a methacryloyl group having an increased photopolymerization activity by a special bonding mode are provided. The unsaturated ester monourethane having the following formula, that is, the unsaturated ester monourethane represented by the above formula 1 is used.

The composition for optical stereolithography of the present invention comprises an unsaturated ester monourethane represented by the formula 1 and a vinyl monomer, and the vinyl monomer is (meth) acrylic acid morpholide. It is composed of a single system or a mixed system of (meth) acrylic acid morpholide and diol di (meth) acrylate.

As (meth) acrylic acid morpholide,
Examples thereof include acrylic acid morpholide and methacrylic acid morpholide, with acrylic acid morpholide being preferred.

The diol di (meth) acrylate used when mixed with (meth) acrylic acid morpholide is 1) ethylene glycol, propylene glycol,
1,4-butanediol, neopentyl glycol,
Diacrylate or dimethacrylate of alkanediol having 2 to 6 carbon atoms such as 1,6-hexanediol, 2)
Cyclohexanedimethanol, cyclohexenedimethanol, dicyclopentyldimethanol, etc., having 6 to 1 carbon atoms
2) Diacrylate or dimethacrylate of a diol having an alicyclic hydrocarbon group, 3) The above alkanediol or a diol having an alicyclic hydrocarbon group has 4 to 6 carbon atoms.
1,6-hexanediol hydroxycaprate diacrylate or dimethacrylate, neopentylglycol hydroxypivalate diacrylate or dimethacrylate obtained by reacting an aliphatic lactone or an aliphatic oxycarboxylic acid of ) Diacrylate or dimethacrylate of ester diol, 4) 2,
2-bis (hydroxyethoxyphenyl) propane,
Diacrylate or dimethacrylate of alkoxylated bisphenol having 2 to 3 carbon atoms of alkoxyl group such as 2,2-bis (hydroxydiethoxyphenyl) propane, bis (hydroxypropoxyphenyl) methane and bis (hydroxydipropoxyphenyl) methane Is mentioned.

In the present invention, when a mixed system of (meth) acrylic acid morpholide and diol di (meth) acrylate is used as the vinyl monomer, (meth) acrylic acid morpholide accounts for 50% by weight or more in the vinyl monomer. The content is preferably contained in a ratio, and more preferably 70% by weight or more.

In the composition for optical three-dimensional molding of the present invention, the ratio of unsaturated ester monourethane to vinyl monomer is such that unsaturated ester monourethane / vinyl monomer = 100/25 to 100/150. (Weight ratio), and preferably 100/40 to 100/100 (weight ratio).

The composition for optical three-dimensional molding of the present invention comprises the above-mentioned predetermined ratio of unsaturated ester monourethane and vinyl monomer, and further has an average particle diameter of 0.1 to 50 μm.
The solid fine particles and one or more fillers selected from inorganic fiber whiskers having an average fiber length of 1 to 70 μm may be contained. When using solid fine particles as the filler, those having an average particle diameter of 3 μm or more are preferable, and when using inorganic fiber whiskers as the filler, those having an average fiber diameter of 0.3 to 1 μm and an average fiber length of 10 μm or more are preferable. preferable. Examples of the filler include 1) inorganic solid fine particles such as silica, alumina, clay, calcium carbonate and glass beads, 2) organic solid fine particles such as crosslinked polystyrene, polymethylmethacrylate and polymethylsiloxane, 3) potassium titanate fiber,
Inorganic fiber whiskers such as magnesium sulfate fiber, magnesium borate fiber, aluminum borate fiber, and carbon fiber can be used. When these fillers are contained, the ratio of the filler is 50 to 400 parts by weight per 100 parts by weight of the total amount of the unsaturated ester monourethane and vinyl monomer described above. These fillers may be used alone or in combination of two or more, but it is preferable to use both the inorganic solid fine particles and the inorganic fiber whiskers as the filler. In this case, the unsaturated ester monourethane and vinyl monomer described above are used. Per 100 parts by weight of total amount,
It is more preferable to use 40 to 300 parts by weight of the inorganic solid fine particles and 10 to 100 parts by weight of the inorganic fiber whiskers.

When the composition for optical three-dimensional modeling of the present invention is subjected to optical three-dimensional modeling, a photopolymerization initiator is previously added to the composition. The present invention does not particularly limit the type of photopolymerization initiator used, but as such a photopolymerization initiator,
1) carbonyl compounds such as benzoin, α-methylbenzoin, anthraquinone, chloranthraquinone and acetophenone, 2) sulfur compounds such as diphenyl sulfide, diphenyl disulfide and dithiocarbamate,
3) Polycyclic aromatic compounds such as α-chloromethylnaphthalene and anthracene are listed. The content of the photopolymerization initiator is usually 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, per 100 parts by weight of the total amount of the unsaturated ester monourethane and the vinyl monomer described above. To be A photosensitizer such as n-butylamine, triethanolamine, N, N-dimethylaminobenzenesulfonic acid diallylamide, or N, N-dimethylaminoethyl methacrylate can be used together with the photopolymerization initiator.

The present invention does not particularly limit the optical three-dimensional modeling method to which the composition for optical three-dimensional modeling of the present invention is applied. Various methods are known as such an optical three-dimensional modeling method (JP-A-56-144478, JP-A-60-2).
47515, JP-A-1-204915, JP-A-3-41.
126 etc.), for example, a cured layer of the optical stereolithography composition is formed first, and then a new optical stereolithography composition is supplied onto the cured layer to form the cured layer. There is a method of forming a desired three-dimensional model by repeating the operation of forming. This three-dimensional object can be further post-cured if necessary. Examples of energy rays used for curing include visible rays, ultraviolet rays, and electron rays, and ultraviolet rays are preferable.

Hereinafter, the constitution and effects of the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In the following Examples and Comparative Examples, parts mean parts by weight and% means% by weight unless otherwise specified.

[0025]

【Example】

Test Category 1 (Preparation of composition for optical three-dimensional modeling) -Preparation of Examples 1-8 and Comparative Examples 1-5 Unsaturated ester monourethane A- according to the synthesis method described in JP-A-4-53809. 1 {glycerin monoacrylate / monomethacrylate / methacryloyloxyethyl isocyanate = 1/1 (molar ratio)} was synthesized. Synthesized unsaturated ester urethane A
-1 and 100 parts of acrylic acid morpholide were mixed and dissolved at room temperature to prepare an optical three-dimensional structure forming composition of Example 1. In the same manner as in Example 1, the compositions for optical stereolithography of Examples 2-8 and Comparative Examples 1-5 were prepared. These compositions are summarized in Table 1.

[0026]

[Table 1]

In Table 1, A-1: glycerin monoacrylate monomethacrylate / methacryloyloxyethyl isocyanate = 1 /
Reaction product 1 (molar ratio) A-2: Glycerine diacrylate / methacryloyloxypropyl isocyanate = 1/1 (molar ratio) A-3: Trimethylolpropane diacrylate / methacryloyloxyethyl isocyanate = 1/1 ( (Mole ratio) B-1: acrylic acid morpholide B-2: methacrylic acid morpholide C-1: neopentyl glycol diacrylate C-2: dicyclopentyl dimethylene diacrylate C-3: neopentyl glycol hydroxypivale Todiacrylate R-1: Reaction product of glycerin dimethacrylate / acryloyloxyethyl isocyanate = 1/1 (molar ratio) R-2: Glycerin monoacrylate monomethacrylate / acryloyloxyethyl isocyanate = 1/1
Reaction product (molar ratio) R-3: Glycerin diacrylate / acryloyloxypropyl isocyanate = 1/1 (molar ratio) R-4: Glycerin dimethacrylate / methacryloyloxyethyl isocyanate = 1/1 (molar ratio) Reaction product R-5: reaction product of glycerin monomethacrylate / acryloyloxyethyl isocyanate = 1/2 (molar ratio)

Test Category 2 (Preparation of 3-D object and its evaluation) 1) Preparation of 3-D object Mainly composed of a three-dimensional NC table equipped with a container and a helium / cadmium laser light (output 25 mW, wavelength 3250 Å) control system. The constructed optical three-dimensional modeling apparatus was used. The above-mentioned container was filled with 3 parts of 1-hydroxycyclohexyl phenyl ketone dissolved as a photopolymerization catalyst per 100 parts of the composition for optical stereolithography prepared in Test Category 1 (hereinafter, simply referred to as mixed solution). The container was supplied with a thickness of 0.10 mm from the container to a horizontal plane (X-Y axis plane) and was focused from a direction (Z-axis direction) perpendicular to the surface (XY axis plane). The helium / cadmium laser beam was scanned to cure the resin for optical three-dimensional modeling. Next, a new mixed liquid having a thickness of 0.10 mm was supplied onto the cured product and cured in the same manner. Thereafter, in the same manner, a total of 200 layers were laminated to form a conical solid body having a design value of a bottom surface diameter of 200.00 mm and a height of 20.00 mm. The obtained modeled product was washed with isopropyl alcohol and irradiated with a 3 kW ultraviolet lamp for 30 minutes for post-curing to obtain a three-dimensional modeled product.

2) Measurement of mechanical properties In the same manner as 1), a dumbbell shape having a thickness of 3 mm specified in JIS K7113 is optically modeled, and the modeled object is washed with isopropyl alcohol and then at 98 ° C. for 2 hours. A test piece was prepared by heating and post-curing. Three identical test pieces were prepared, and according to JIS K7113, the tensile strength, the tensile elastic modulus, and the tensile elongation were measured at a tensile speed of 5 mm / sec. Further, a toughness value (Tf) represented by tensile strength × tensile elongation was calculated. The results are shown in Table 2 as an average value of three test pieces.

3) Evaluation of thermal physical properties In the same manner as the test piece of 2), a 55 mm × 10 mm × 2 mm flat plate type test piece was prepared. The dynamic viscoelasticity of this test piece was measured, and the glass transition temperature (T
g) was determined. The results are shown in Table 2.

4) Measurement of shape Regarding the three-dimensional object obtained in 1), 2 on the XY axis plane.
The two-dimensional figure a was vertically projected, and the two-dimensional figure b was horizontally projected on arbitrary 50 planes perpendicular to the X-Y axis plane, and the following measurements were performed on these projections. The results are shown in Table 3. The two-dimensional figure a obtained here is a circle, and the two-dimensional figure b is a triangle. Two-dimensional figure a: Draw 50 arbitrary straight lines passing through the center of gravity of the projected view, measure the distance between two points intersecting the contour of the projected view,
For these measured values, the average value, maximum value, minimum value and standard deviation were calculated. Two-dimensional figure b: The area of 50 projection views was measured, and the average value, maximum value, minimum value and standard deviation were calculated for these measured values.

[0032]

[Table 2]

[0033]

[Table 3]

In Table 2 and Table 3, Comparative Example 6: ABS resin (Diapet HF-5 manufactured by Mitsubishi Rayon Co., Ltd.) Incidentally, a test piece for measuring mechanical properties and a test for measuring thermal physical properties of Comparative Example 6. Cylinder temperature 200 ℃, mold temperature 60
Injection molded at ° C. The size and shape of the injection molded product are the same as those in 2) and 3) above.

Test Category 3 (Preparation of Optical Stereolithography Composition) Preparation of Examples 9 to 12 and Comparative Examples 7 to 100 100 parts of optical stereolithography composition of Example 1 prepared in Test Category 1 , Photopolymerization initiator 3 parts, inorganic solid fine particles 200
Parts and 50 parts of inorganic fiber whiskers were put into a mixing tank equipped with a biaxial stirrer and sufficiently stirred and mixed until uniform.
Filtering the stirred mixture through a 50 μm filter,
The composition for optical stereolithography of Example 9 was prepared. In the same manner as in Example 9, the compositions for optical stereolithography of Examples 10 to 12 and Comparative examples 7 to 10 were prepared. These compositions are summarized in Table 4.

[0036]

[Table 4]

In Table 4, D-1: Aluminum borate whiskers having an average fiber diameter of 0.8 μm × average fiber length of 20 μm (Arborex YS-4 manufactured by Shikoku Kasei) E-1: Glass beads having an average particle diameter of 30 μm (GB-730C manufactured by Toshiba Barodyni) E-2: Aluminum hydroxide having an average particle diameter of 8 μm (B-103 manufactured by Nippon Light Metal Co., Ltd.) F-1: 1-hydroxycyclohexyl phenyl ketone

Test Category 4 (Preparation of 3-D Model and Evaluation thereof) 1) Preparation of 3-D Model Using the composition for optical 3-D model prepared in Test section 3,
In the same manner as in the production of the three-dimensional shaped object of Test Category 2, a conical three-dimensional object having a design value of a bottom surface diameter of 200.00 mm and a height of 20.00 mm was formed. The obtained modeled product was washed with isopropyl alcohol, heated at 98 ° C. for 2 hours and post-cured to obtain a three-dimensional modeled product.

2) Measurement of mechanical properties, thermal properties and shape Test pieces prepared separately in the same manner as in Test Category 2 and 1)
The mechanical properties, thermal properties, and shape of the three-dimensional molded object manufactured in Section 3 were measured. The results are shown in Tables 5 and 6.

[0040]

[Table 5]

[0041]

[Table 6]

In Tables 5 and 6, Comparative Examples 7 and 8: Cracks were found on the surface of the three-dimensional molded article.

[0043]

As is apparent from the above, the present invention described above has an effect that it is possible to obtain a three-dimensional object excellent in mechanical properties and thermal properties and in shape accuracy.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B29K 105: 24 503: 04

Claims (5)

[Claims] 1. An unsaturated ester monourethane represented by the following formula 1 and the following vinyl monomer, wherein the unsaturated ester monourethane / the vinyl monomer = 100/25
The composition for optical three-dimensional modeling, characterized in that the composition is in the ratio of 100 to 150 (weight ratio). (Equation 1) (In the formula 1, X: a residue obtained by removing a hydroxyl group from a trihydric alcohol R ¹ : H or CH ₃ R ² : an alkylene group having 2 to 6 carbon atoms) Vinyl monomer: (meth) acrylic acid morpholide or (meth ) A mixture of acrylic acid morpholide and diol di (meth) acrylate 2. The composition for optical stereolithography according to claim 1, wherein the vinyl monomer contains 50% by weight or more of (meth) acrylic acid morpholide. 3. The diol di (meth) acrylate is a di (meth) acrylate of an alkanediol having 2 to 6 carbon atoms, a di (meth) acrylate of a diol having an alicyclic hydrocarbon group having 6 to 12 carbon atoms, and carbon. Di (meth) acrylate of ester diol obtained by reacting C2-6 alkanediol with C4-6 oxycarboxylic acid and di (meth) acrylate of alkoxylated bisphenol C2-3 of alkoxyl group 1 selected from
The composition for optical three-dimensional modeling according to claim 1 or 2, which is one kind or two or more kinds. 4. An average particle size of 0.1 to 5 per 100 parts by weight of the optical three-dimensional structure forming composition according to claim 1, 2 or 3.
A composition for optical three-dimensional modeling, which contains solid particles of 0 μm and one or more fillers selected from inorganic fiber whiskers having an average fiber length of 1 to 70 μm in a proportion of 50 to 400 parts by weight. 5. The filler is an inorganic fiber whisker 10-1.
The composition for optical three-dimensional modeling according to claim 4, which comprises 00 parts by weight and 40 to 300 parts by weight of inorganic solid fine particles.