JP5477156B2 - Curable resin composition for producing transparent laminate, transparent laminate and method for producing the same - Google Patents

Description

The present invention is transparent laminate for producing a curable resin composition used in the method for producing a transparent laminate by curing the sandwiched hardenable resin composition between a pair of transparent substrates, the transparent laminate produced transparent laminate having a layer of a cured resin made of a cured product of the use curable resin composition, and to a method for producing a transparent laminate using the transparent laminate for producing a curable resin composition.

  As a transparent laminate having a pair of transparent substrates and an adhesive resin layer sandwiched between the transparent substrates, a laminated glass obtained by integrating a pair of glass plates via an adhesive resin layer is known. Yes. The laminated glass is used as a windshield for automobiles because broken glass does not adhere to the film-like adhesive resin layer and scatter. In addition, the laminated glass is used as a window glass for buildings (safety glass, security glass, etc.) because it is difficult to penetrate and has excellent strength. Therefore, the adhesive resin layer of the transparent laminate is required to have excellent transparency and good adhesion to a transparent substrate and tear resistance.

The following methods are known as a method for producing laminated glass.
(1) A method for producing a laminated glass by sandwiching an adhesive resin film between a pair of transparent substrates and thermocompression bonding the laminate.
(2) A method for producing a laminated glass by injecting a liquid curable resin between a pair of transparent substrates whose peripherals are sealed (Patent Document 1).

The method (2) has a wider variety of curable resins than the method (1), and it is easy to obtain a cured product having various physical properties according to the purpose, and an easily curable resin (especially a photocurable resin). ) Can be used to simplify the manufacturing process.
However, the method (2) has a drawback that bubbles tend to remain in the resin when the curable resin is injected.

As a method for preventing the generation of bubbles, a vacuum lamination method is known. For example, the following method is known as a method for producing laminated glass by the reduced pressure lamination method.
(3) A layer of the photocurable resin composition is formed on one transparent substrate, and another transparent substrate is stacked on the layer of the photocurable resin composition under reduced pressure to form a pair of transparent A process for producing a laminated glass in which a photocurable resin composition is sealed between substrates and then photocured under atmospheric pressure (Patent Document 2).

  As a photocurable resin, a photocurable resin composition containing an unsaturated urethane oligomer has been proposed (Patent Document 1). Moreover, as a photocurable resin suitable for the reduced pressure lamination method, a photocurable resin composition containing an unsaturated urethane oligomer is known (Patent Document 3).

JP 2005-041747 A International Publication No. 08/081838 Pamphlet International Publication No. 09/016943 Pamphlet

  In the said photocurable resin composition, the characteristic of hardened | cured material can be adjusted by designing suitably the polyol component and polyisocyanate used as the raw material of an unsaturated urethane oligomer. For example, a flexible cured product can be obtained by using a polyol having a small hydroxyl value (a high molecular weight per hydroxyl group). Moreover, the characteristic of hardened | cured material can further be adjusted by using various monomers together with unsaturated urethane oligomer.

  However, when only a polyol having a small hydroxyl value is used, the compatibility between the resulting unsaturated urethane oligomer and the monomers is significantly reduced, so the transparency of the cured product is not sufficient and a high haze value is exhibited. There is. In addition, the adhesion between the transparent substrate and the cured product tends to be insufficient.

  In addition, in order for the cured product to exhibit good tear resistance, a balance between the strength and elongation of the cured product is important. However, if a polyol having a small hydroxyl value (high molecular weight per hydroxyl group) is used, the number of crosslinking points is reduced and the strength becomes insufficient. On the other hand, if a polyol having a large hydroxyl value (low molecular weight per hydroxyl group) is used, , The elongation becomes insufficient. Therefore, it is difficult to design a polyol component for obtaining a cured product having excellent tear resistance.

  The present invention provides a curable resin composition that can obtain a cured product that has good transparency and is excellent in adhesion to a transparent substrate and tear resistance. Moreover, the curable resin composition used for the method of manufacturing a transparent laminated body is provided. Furthermore, the present invention provides a transparent laminate having good transparency, excellent adhesion between a transparent substrate and a cured resin layer, and excellent tear resistance of the cured resin layer, and a method for producing the same.

The present invention is the following [1] to [9].
[1] A curable resin composition for producing a transparent laminate, which is used in a method for producing a transparent laminate by curing a curable resin composition sandwiched between a pair of transparent substrates,
The following unsaturated urethane oligomer (A), viewed contains the following monomer (B), and the following monomer (C),
In 100% by mass of the curable resin composition for producing a transparent laminate, the proportion of the unsaturated urethane oligomer (A) is 20 to 60% by mass, and the proportion of the monomer (B) is 25 to 50% by mass. A curable resin composition for producing a transparent laminate , wherein the ratio of the monomer (C) is 3 to 50% by mass .
Unsaturated urethane oligomer (A): The following polyol component (A1) and polyisocyanate (A2) are reacted at a ratio of isocyanate group: hydroxyl molar ratio of 1.2: 1 to 3: 1 to give an isocyanate group-terminated urethane. A reaction product obtained by reacting an isocyanate group-terminated urethane prepolymer with the unsaturated hydroxy compound (A3) described below at a ratio such that the molar ratio of isocyanate group: hydroxyl group is 1: 1 to 1: 1.5 . An unsaturated urethane oligomer having an average of 2 to 4 curable functional groups per molecule.
Polyol component (A1): A polyol component containing the following polyol (a1) and 0.5 to 2 mol of the following polyol (a2) with respect to 1 mol of the polyol (a1).
Polyol (a1): A polyoxyalkylene polyol having a hydroxyl value of 15 to 40 mgKOH / g, obtained by reacting an initiator having 2 active hydrogen atoms with monoepoxide.
Polyol (a2): a polyoxyalkylene polyol obtained by reacting an initiator having 2 or 3 active hydrogens with monoepoxide, or a polyhydric alcohol having 2 or 3 hydroxyl groups, and having a hydroxyl value of 55 to 1 , 830 mg KOH / g polyol.
Unsaturated hydroxy compound (A3): A compound having the following curable functional group and hydroxyl group.
Curable functional group: a group represented by CH ₂ ═C (R) C (O) O— (wherein R represents a hydrogen atom or a methyl group) .
Monomer (B): Compound represented by CH ₂ ═C (R) C (O) O—R ² (wherein R represents a hydrogen atom or a methyl group, R ² has 1 to ² hydroxyl groups) And represents a hydroxyalkyl group having 3 to 4 carbon atoms) .
Monomer (C): a compound represented by CH ₂ ═C (R) C (O) O—R ³ (wherein R represents a hydrogen atom or a methyl group, and R ³ has 8 to 22 carbon atoms) Represents an alkyl group).
[ 2 ] The curable resin composition for producing a transparent laminate according to the above [ 1] , further comprising a photopolymerization initiator (D).
[ 3 ] A transparent laminate having a pair of transparent substrates and a cured resin layer sandwiched between the transparent substrates, wherein the cured resin is the transparent laminate according to the above [ 1 ] or [ 2] The transparent laminated body which is a hardened | cured material of curable resin composition for body manufacture .
[ 4 ] In a reduced-pressure atmosphere, a sealed space containing the curable resin composition for producing a transparent laminate according to the above [ 1 ] or [ 2] is formed between a pair of transparent substrates. A first step of producing a laminated precursor having a transparent substrate and the curable resin composition for producing a transparent laminate sealed between the pair of transparent substrates; and A method for producing a transparent laminate , comprising: a second step of placing in a high pressure atmosphere and curing the curable resin composition for producing the transparent laminate in the atmosphere.
[ 5 ] The method for producing a transparent laminate according to [ 4 ], wherein the reduced-pressure atmosphere is a pressure atmosphere of 100 Pa or less, and the atmosphere having a higher pressure than the reduced-pressure atmosphere is an atmospheric pressure atmosphere.
[ 6 ] The curable resin composition for producing a transparent laminate is a photocurable resin composition, and in the second step, the laminate precursor is irradiated with light to produce the curable resin composition for producing a transparent laminate . The manufacturing method of the transparent laminated body as described in said [ 4 ] or [ 5 ] which cures.

According to the curable resin composition for producing a transparent laminate of the present invention, a cured product having good transparency and excellent adhesion to a transparent substrate and tear resistance can be obtained.
The transparent laminate of the present invention has good transparency, and excellent adhesion between the transparent substrate and the cured resin layer and the tear resistance of the cured resin layer.
According to the method for producing a transparent laminate of the present invention, it is possible to produce a transparent laminate having good transparency and excellent adhesion between the transparent substrate and the cured resin layer and tear resistance of the cured resin layer.

It is sectional drawing which shows 1 process in manufacture of a transparent laminated body.

In this specification, the curable functional group represented by CH ₂ ═C (R) C (O) O— (wherein R represents a hydrogen atom or a methyl group) is an acryloyloxy group (where R is a hydrogen atom). Or a methacryloyloxy group (when R is a methyl group), and the group represented by the formula is also referred to as a (meth) acryloyloxy group. Similarly, “(meth) acrylate” is used as a general term for “acrylate” and “methacrylate”.

<Curable resin composition for producing transparent laminate >
The curable resin composition for producing a transparent laminate of the present invention (hereinafter, also simply referred to as curable resin composition ) is a curable resin composition containing an unsaturated urethane oligomer (A), and includes a pair of transparent substrates. a curable resin composition used in the method for producing a transparent laminate by curing the sandwiched hardenable resin composition in between.

(Unsaturated urethane oligomer (A))
The unsaturated urethane oligomer (A) is a reaction product of the polyol component (A1), the polyisocyanate (A2), and the unsaturated hydroxy compound (A3), and has an average of 2 to 4 curable functional groups per molecule. It is an unsaturated urethane oligomer. Hereinafter, the unsaturated urethane oligomer (A) is also referred to as an oligomer (A).

  The unsaturated urethane oligomer (A) has an average of 2 to 4 curable functional groups (that is, (meth) acryloyloxy groups) per molecule. A plurality of curable functional groups present in one molecule may be different (that is, an acryloyloxy group and a methacryloyloxy group may be present in one molecule). However, usually, the plurality of curable functional groups in one molecule are preferably the same curable functional group, and the curable functional group in the oligomer (A) is preferably an acryloyloxy group. The curable functional group in the oligomer (A) tends to be low in reactivity because the oligomer (A) has a high molecular weight, and when used in combination with relatively low molecular weight monomers, In order to reduce the difference in reactivity, it is preferable that the reactivity of the curable functional group of the oligomer (A) is high. Therefore, the curable functional group of the oligomer (A) is preferably an acryloyloxy group having a higher reactivity than the methacryloyloxy group.

The average number of curable functional groups per molecule of the oligomer (A) is 2 to 4, and preferably 2 to 3. If the average number of curable functional groups per molecule of the oligomer (A) is 2 or more, the cured product is hardly deformed even when exposed to high temperatures. If the average number of curable functional groups per molecule of the oligomer (A) is 4 or less, the cured product is difficult to become brittle.
The average number of curable functional groups per molecule of the oligomer (A) is the number of hydroxyl groups of the polyol component (A1) described later, the number of isocyanate groups of the polyisocyanate (A2), the number of curable functional groups of the unsaturated hydroxy compound (A3), and the number of hydroxyl groups. Adjusted by number. The polyisocyanate (A2) is preferably a diisocyanate having 2 isocyanate groups, and the unsaturated hydroxy compound (A3) is preferably an unsaturated monool having a curable functional group number of 1, so that these can be used. The average number of curable functional groups per molecule of the oligomer (A) is usually substantially the same as the average number of hydroxyl groups per molecule of the polyol component (A1). For example, by using only a diol as the polyol component (A1), an oligomer (A) having an average number of curable functional groups per molecule of 2 can be obtained. Similarly, by using diol and triol as the polyol component (A1), an oligomer (A) having an average curable functional group number between 2 and 3 is obtained, and by using only triol as the polyol component (A1). An oligomer (A) having an average number of curable functional groups of 3 is obtained.

The oligomer (A) is a reaction product of the three kinds of raw material compounds. Examples of the method for obtaining the reaction product include the following methods (1) to (3), and the method (3): Is preferred.
(1) A method of simultaneously reacting a polyol component (A1), a polyisocyanate (A2) and an unsaturated hydroxy compound (A3).
(2) The polyisocyanate (A2) and the unsaturated hydroxy compound (A3) are reacted stoichiometrically with an excess of isocyanate groups, and the resulting reaction product is further reacted with the polyol component (A1). Method.
(3) After reacting the polyol component (A1) and the polyisocyanate (A2) in a stoichiometrically excess condition with an isocyanate group, the resulting reaction product is further reacted with an unsaturated hydroxy compound (A3). Method.

Examples of the method (3) include a method having the following step (3-1) and step (3-2).
(3-1) If necessary, the polyol component (A1) and the polyisocyanate (A2) are reacted in a stoichiometrically excessive condition with an isocyanate group in the presence of a urethanization catalyst to obtain an isocyanate group-terminated urethane prepolymer. Obtaining step.
(3-2) A step of reacting the unsaturated hydroxy compound (A3) with the isocyanate group at the end of the isocyanate group-terminated urethane prepolymer in the presence of a polymerization inhibitor as necessary.

Step (3-1):
Examples of the urethanization catalyst include cobalt naphthenate, zinc naphthenate, zinc 2-ethylhexanoate, dibutyltin dilaurate, tin 2-ethylhexanoate, triethylamine, 1,4-diabicyclo [2.2.2] octane, and the like. It is done.
The ratio of the polyol component (A1) and the polyisocyanate (A2) is preferably such that the molar ratio of isocyanate group: hydroxyl group is 1.2: 1 to 3: 1, and is 1.2: 1 to 2: 1. A ratio is more preferable. The reaction temperature is preferably a temperature in a normal urethanization reaction, that is, 30 to 90 ° C.

Step (3-2):
Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, 2,6-di-tert-butyl-hydroquinone, o-nitrotoluene and the like. The amount of the polymerization inhibitor is preferably 50 to 5,000 ppm with respect to the unsaturated hydroxy compound (A3).
The ratio of the isocyanate group-terminated urethane prepolymer and the unsaturated hydroxy compound (A3) is preferably such that the molar ratio of isocyanate group: hydroxyl group is 1: 1 to 1: 1.5. The reaction temperature is preferably 30 to 90 ° C.

  When the oligomer (A) is obtained by the method (1), the polyisocyanate (A2), the polyol component (A1) and the unsaturated hydroxy compound (A3) are mixed at a molar ratio of isocyanate group: hydroxyl group of 0.8. : It is preferable to use in the ratio which will be 1-2: 1.

(Polyol component (A1))
The polyol component (A1) is a polyol component containing the polyol (a1) and the polyol (a2) as essential components, and may contain another polyol (a3) as necessary.

(Polyol (a1))
The polyol (a1) is a polyoxyalkylene polyol having a hydroxyl value of 15 to 40 mgKOH / g, obtained by reacting a monoepoxide with an initiator having 2 active hydrogen atoms.

  The polyol (a1) is a polyol having a polyoxyalkylene chain composed of an oxyalkylene group, and is preferably a polyoxyalkylene polyol obtained by reacting a monoepoxide with an initiator in the presence of a catalyst. In particular, a polyoxyalkylene polyol obtained by reacting an alkylene oxide with an initiator using a double metal cyanide complex as a catalyst is preferable. A polyol (a1) may be used individually by 1 type, and may use 2 or more types together.

  Examples of the catalyst include diethyl zinc, iron chloride, metalloporphyrin, double metal cyanide complex, cesium compound, alkali (earth) metal compound, and double metal cyanide complex is preferable. When a polyoxyalkylene polyol having a low hydroxyl value is obtained by reacting propylene oxide with a general-purpose alkali metal compound catalyst (potassium hydroxide, etc.), the isomerization reaction of propylene oxide easily occurs and the degree of unsaturation is high. Become. The cured product containing the oligomer (A) obtained using the polyoxyalkylene polyol having a high degree of unsaturation may have insufficient mechanical properties. The degree of unsaturation (USV) of the polyol (a1) is preferably 0.05 meq / g or less.

  As the double metal cyanide complex, a complex mainly composed of zinc hexacyanocobaltate is preferable, and an ether and / or alcohol complex of zinc hexacyanocobaltate is particularly preferable. Examples of the ether and / or alcohol complex of zinc hexacyanocobaltate include those described in JP-B-46-27250. As the ether, ethylene glycol dimethyl ether (glyme), diethylene glycol dimethyl ether and the like are preferable, and glyme is particularly preferable from the viewpoint of easy handling at the time of producing the complex. As the alcohol, tert-butanol, tert-butyl cellosolve and the like are preferable.

  The number of active hydrogens in the initiator is 2. The active hydrogen means an active hydrogen atom with which monoepoxide can react, such as a hydrogen atom of a hydroxyl group or a hydrogen atom of an amino group. As the active hydrogen, a hydrogen atom of a hydroxyl group is preferable. Therefore, a polyhydroxy compound having 2 hydroxyl groups is preferable as the initiator. Examples of the initiator include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, and polyol (a1) obtained by reacting these with alkylene oxide. And lower molecular weight polyoxyalkylene polyols. When a double metal cyanide complex is used, the molecular weight of the initiator is preferably 500 to 1,500. An initiator may be used individually by 1 type and may use 2 or more types together.

  Monoepoxide is a compound having one epoxy ring. Examples of the monoepoxide include alkylene oxide, glycidyl ether, and glycidyl ester, and alkylene oxide is preferable. Examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, styrene oxide, and the like, and ethylene oxide and propylene oxide are preferable. Monoepoxide may be used individually by 1 type, and may use 2 or more types together.

  The polyol (a1) is preferably a polyoxypropylene polyol obtained using only propylene oxide as the monoepoxide, or a poly (oxypropylene / oxyethylene) polyol obtained using propylene oxide and a small amount of ethylene oxide as the monoepoxide. .

  The number of hydroxyl groups per molecule of the polyol (a1) is 2. If the number of hydroxyl groups per molecule of the polyol (a1) is 2, an oligomer (A) having an average number of curable functional groups per molecule of 2 to 4 can be easily obtained.

The hydroxyl value of the polyol (a1) is 15 to 40 mgKOH / g, and preferably 16.8 to 30 mgKOH / g. When the hydroxyl value of the polyol (a1) is 15 mgKOH / g or more, the strength of the cured product is good. Moreover, since the molecular weight of the polyol (a1) does not become too large, the viscosity of the polyol (a1) does not become too large, and there is no problem in workability.
When the hydroxyl value of the polyol (a1) is 40 mgKOH / g or less, the flexibility of the cured product is good.
The hydroxyl value of the polyol (a1) is measured according to JIS K1557-1 (2007 edition). The same applies to the hydroxyl value of other polyols.

(Polyol (a2))
The polyol (a2) is a polyoxyalkylene polyol obtained by reacting a monoepoxide with an initiator having 2 or 3 active hydrogen atoms, or a polyhydric alcohol having 2 or 3 hydroxyl groups, and has a hydroxyl value of 55 to 55. It is a polyol of 1,830 mg KOH / g.
A polyol (a2) may be used individually by 1 type, and may use 2 or more types together.

Polyol (a2), which is a polyoxyalkylene polyol, is preferably a polyoxyalkylene polyol obtained by reacting a monoepoxide with an initiator in the presence of a catalyst. An alkylene oxide is used as an initiator with a composite metal cyanide complex as a catalyst. Polyoxyalkylene polyols obtained by reacting are particularly preferred.
The number of active hydrogens in the initiator is 2 or 3. As the active hydrogen, a hydrogen atom of a hydroxyl group is preferable. Therefore, as the initiator, a polyhydroxy compound having 2 or 3 hydroxyl groups is preferable. As initiators, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, obtained by reacting these with alkylene oxide And a polyoxyalkylene polyol having a lower molecular weight than that of the polyol (a2). An initiator may be used individually by 1 type and may use 2 or more types together.
As the polyoxyalkylene polyol, a polyoxypropylene polyol obtained by using only propylene oxide as a monoepoxide is preferable.

  As the polyol (a2) which is a polyhydric alcohol, alkylene glycol, dialkylene glycol and alkanetriol are preferable. The number of carbon atoms of the polyhydric alcohol is preferably 10 or less. Specific examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, and the like. .

  The number of hydroxyl groups per molecule of the polyol (a2) is 2 or 3. If the number of hydroxyl groups is 2 or 3, an oligomer (A) having an average number of curable functional groups per molecule of 2 to 4 can be easily obtained.

  The hydroxyl value of the polyol (a2) is 55 to 1,830 mg KOH / g. By adding the polyol (a2) having a hydroxyl value of 55 mgKOH / g or more, the affinity with the hydroxyl group on the surface of the transparent substrate (glass plate) is improved, and the adhesion between the cured product and the transparent substrate is improved. Moreover, a hardened | cured material becomes tough because the urethane crosslinking density which is a strong bond increases on the bond strength of a molecule | numerator. However, when the hydroxyl value of the polyol (a2) exceeds 1,830 mgKOH / g, the hydrophilicity becomes too high, the compatibility with the monomer (B) and the like is lowered, and haze is generated in the cured product. is there. Moreover, since the urethane crosslinking density is remarkably increased, a hard and brittle cured product is obtained.

  The ratio of the polyol (a2) is 0.5 to 3 mol, preferably 1 to 3 mol, relative to 1 mol of the polyol (a1). If the ratio of a polyol (a2) is 0.5 mol or more, adhesiveness with a transparent substrate etc. of hardened | cured material will become favorable. Moreover, hardened | cured material becomes tough by the urethane crosslinking density increasing. However, when the ratio of the polyol (a2) exceeds 4 mol, the viscosity of the oligomer (A) becomes high, which is industrially disadvantageous. Further, the cured product becomes too hard and becomes brittle.

(Polyol (a3))
The polyol (a3) is a polyol that is neither the polyol (a1) nor the polyol (a2). Examples of the polyol (a3) include polyoxyalkylene polyols having a hydroxyl number of 3 or more and a hydroxyl value of less than 55 mgKOH / g. Moreover, polyols, such as a polyester polyol, a polycaprolactone polyol, a polycarbonate polyol, a polybutadiene polyol, are mentioned.
The polyol (a3) is not an essential component, and when the polyol (a3) is used, its mass ratio in the polyol component (A1) is small. The ratio of the polyol (a3) to the polyol component (A1) is preferably 25% by mass or less, and more preferably 10% by mass or less.

(Polyisocyanate (A2))
The polyisocyanate (A2) is an alicyclic polyisocyanate, aliphatic polyisocyanate, aromatic polyisocyanate containing an aromatic ring having an average number of isocyanate groups of 2 or more per molecule, and a modification obtained by modifying these. A polyisocyanate type | system | group etc. are mentioned. Aromatic polyisocyanates having an isocyanate group bonded to an aromatic ring are preferably not used because they are likely to cause yellowing of the cured resin.
2-4 are preferable and, as for the average number of isocyanate groups per molecule of polyisocyanate (A2), 2 is especially preferable. That is, as the polyisocyanate (A2), diisocyanate is preferable. Polyisocyanate (A2) may be used individually by 1 type, and may use 2 or more types together.

  Specific examples of the polyisocyanate (A2) include diisocyanates such as isophorone diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and xylene diisocyanate, prepolymer modified products, nurate modified products, urea modified products, and carbodiimide modified products of the diisocyanate. And isophorone diisocyanate and hexamethylene diisocyanate are particularly preferred.

(Unsaturated hydroxy compound (A3))
The unsaturated hydroxy compound (A3) is a compound having a curable functional group and a hydroxyl group, and two or more curable functional groups may be present in one molecule, and two or more hydroxyl groups are present in one molecule. It may be. In order to produce an oligomer (A) having an average of 2 to 4 curable functional groups, a compound having one curable functional group and one hydroxyl group in one molecule is preferable.

  As the unsaturated hydroxy compound (A3), a hydroxyalkyl (meth) acrylate having a hydroxyalkyl having 1 to 10 carbon atoms is preferable, and a hydroxyalkyl (meth) acrylate having a hydroxyalkyl having 1 to 5 carbon atoms is more preferable. . In order to obtain a highly reactive oligomer (A), the curable functional group is preferably an acryloyloxy group. Accordingly, the unsaturated hydroxy compound (A3) is more preferably a hydroxyalkyl acrylate having a hydroxyalkyl having 1 to 5 carbon atoms.

  Specific examples of the unsaturated hydroxy compound (A3) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4 -Hydroxybutyl (meth) acrylate, pentanediol mono (meth) acrylate, hexanediol mono (meth) acrylate and the like are mentioned, and 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate are preferable, Hydroxyethyl acrylate and 2-hydroxypropyl acrylate are particularly preferable. An unsaturated hydroxy compound (A3) may be used individually by 1 type, and may use 2 or more types together.

(Other ingredients)
The curable resin composition containing the unsaturated urethane oligomer (A) can be used for adhesives, coating agents, and other applications. Various additives can be added to the curable resin composition depending on the application. It is usually essential to add a curing agent for curing the curable resin composition, and a radical generator or a photopolymerization initiator is preferable as the curing agent. A curable resin composition containing a curing agent that generates radicals by heat is a thermosetting type, and a curable resin composition containing a photopolymerization initiator is a photocurable type.

In the curable resin composition containing the unsaturated urethane oligomer (A), monomers such as a monomer (B) and other monomers (F) described later are blended for adjusting the physical properties of the cured product. It is preferable.
As the monomer, a compound having 1 to 6 curable functional groups is preferable, and a compound having 1 to 2 curable functional groups is more preferable. In terms of obtaining a hard cured product, a compound having 3 to 6 curable functional groups is preferred. Moreover, a low viscosity compound is preferable as a monomer from the point which improves the applicability | paintability of curable resin composition. Monomers with low viscosity are sometimes referred to as reactive diluents. Furthermore, you may mix | blend curable compounds other than the said monomers, such as the other oligomer (E) mentioned later.

  Various additives that do not participate in the reaction may be added to the curable resin composition. As this additive, the below-mentioned additive (G) etc. are mentioned, for example. Moreover, in order to improve applicability | paintability, you may use a solvent as components other than the structural component of curable resin composition. The curable resin composition is applied using a solvent, and then the curable resin composition is cured by removing the solvent. However, since it is not preferable to have a volatile component as a curable resin composition suitable for the production of a transparent laminate described later, no solvent is used.

(Transparent laminate Manufacturing curable resin composition)
The curable resin composition used in the method for producing a transparent laminate by curing a curable resin composition sandwiched between a pair of transparent substrates of the present invention comprises an oligomer (A) and a monomer ( wherein B) the monomer and (C) as essential components, preferably contains a photopolymerization initiator (D) in addition, if desired other oligomers (E), another monomer (F), An additive (G) and the like may further be included.

20-100 mass% is preferable among 100 mass% of curable resin compositions, and, as for the ratio of an oligomer (A), 30-50 mass% is more preferable. When the ratio of the oligomer (A) is 20% by mass or more, the cured product is hardly deformed even when exposed to a high temperature. If the ratio of an oligomer (A) is 75 mass% or less, hardened | cured material will become difficult to become weak.
The proportion of the monomer (B) is preferably 25 to 50% by mass and more preferably 35 to 40% by mass in 100% by mass of the curable resin composition. If the ratio of a monomer (B) is 25 mass% or more, adhesiveness with a transparent substrate of a hardened | cured material and tear resistance will become favorable.

The proportion in the case of including the monomer (C) is preferably from 3 to 50 mass%, more preferably from 5 to 25 mass%, out of 100 mass% of the curable resin composition. When the ratio of the monomer (C) is 3% by mass or more, the cured product has good flexibility.
0.01-10 mass parts is preferable with respect to 100 mass parts of oligomers (A), and, as for the quantity in case a photoinitiator (D) is included, 0.1-2.5 mass parts is more preferable.
The proportion of other components (total of other oligomer (E), other monomer (F), additive (G), etc.) is preferably 10% by mass or less in 100% by mass of the curable resin composition. 5 mass% or less is more preferable.

(Monomer (B))
The monomer (B) is a compound represented by CH ₂ ═C (R) C (O) O—R ² (where R represents a hydrogen atom or a methyl group, and R ² has 1 to ² hydroxyl groups). And represents a hydroxyalkyl group having 3 to 4 carbon atoms. The monomer (B) is effective as a component that increases the hydrophilicity of the cured product of the curable composition and improves the affinity between the cured product and the surface of the transparent substrate (glass plate). By using B), the adhesion between the cured product and the transparent substrate is improved. In addition, the strength of the cured product is improved.

  The monomer (B) is a (meth) acrylate having a hydroxyalkyl group or a dihydroxyalkyl group, and is preferably a methacrylate in order to promote the reaction with the oligomer (A) uniformly. That is, even if the curable functional group of the oligomer (A) is an acryloyloxy group, the reactivity is low, and when the curable functional group of the monomer (B) is an acryloyloxy group, the reaction of both curable functional groups. There is a possibility that the difference in property becomes large and uniform curing cannot be obtained. Therefore, a combination in which the curable functional group of the oligomer (A) is an acryloyloxy group and the curable functional group of the monomer (B) is a methacryloyloxy group is preferable. A monomer (B) may be used individually by 1 type, and may use 2 or more types together.

When the number of hydroxyl groups of the monomer (B) exceeds 2, the cured product becomes more hydrophilic, but the cured product becomes harder and more fragile. Therefore, the number of hydroxyl groups in R ² is 1 to 2, and 1 is more preferable.
When the carbon number of R ² is less than 3, the hydroxyl group density tends to be high, and when a curable resin composition is obtained in combination with the oligomer (A) having a long chain structure, partial phase separation occurs during the curing reaction. It becomes easy, a haze occurs in the cured product, and transparency tends to be lowered. When the number of carbon atoms of R ² exceeds 4, there are cases where the hydroxyl group density decreases, sufficient adhesion can not be obtained. Therefore, the number of carbon atoms in ^{R 2} is 3-4.

  Examples of the monomer (B) include 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate and the like, and 2-hydroxybutyl methacrylate is preferable.

(Monomer (C))
The monomer (C) is a compound represented by CH ₂ ═C (R) C (O) O—R ³ (wherein R represents a hydrogen atom or a methyl group, and R ³ has 8 to 22 carbon atoms) Represents an alkyl group. For the same reason as the monomer (B), the monomer (C) is preferably methacrylate, but the monomer (C) has a higher molecular weight than the monomer (B), so it may be An acrylate may also be used. A monomer (C) may be used individually by 1 type, and may use 2 or more types together.

  When the curable resin composition contains the monomer (C), the elastic modulus of the cured product is lowered and the tear resistance is easily improved. Moreover, if carbon number of an alkyl group is 8 or more, there is little volatility and the glass transition temperature of hardened | cured material can be reduced. When the carbon number of the alkyl group is 22 or less, the alcohol component of the raw material can be easily obtained via a natural product and is more industrial.

  Examples of the monomer (C) include n-dodecyl methacrylate, n-octadecyl methacrylate, n-behenyl methacrylate and the like, and n-dodecyl methacrylate and n-octadecyl methacrylate are particularly preferable.

(Photopolymerization initiator (D))
When the curable resin composition of this invention contains a photoinitiator (D), it becomes a photocurable resin composition.
As the photopolymerization initiator (D), those which are excited by irradiation with visible light or ultraviolet light (wavelength 300 to 400 nm) and are activated to promote the curing reaction are preferable. A benzoin ether photopolymerization initiator, α-hydroxyalkyl Examples include phenone photopolymerization initiators and acylphosphine oxide photopolymerization initiators.

  Specific examples of the photopolymerization initiator (D) include benzophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, acetophenone, 3-methylacetophenone, benzoyl, benzoin isobutyl ether, benzoin Isopropyl ether, benzoin ethyl ether, anthraquinone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2- Examples thereof include hydroxy-2-methyl-1-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 1- [4- (2- Hydro Ethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and the like are preferable, and are sufficiently cured even with a small amount of addition. An acyl phosphine oxide-based photopolymerization initiator such as bis (2,4,6-trimethylbenzoyl) -phenyl phosphine oxide is particularly preferred from the viewpoint that the conductive resin composition can be cured. A photoinitiator (D) may be used individually by 1 type, and may use 2 or more types together.

(Other oligomer (E))
The curable resin composition of the present invention may contain a small amount of an oligomer (E) other than the oligomer (A) for the purpose of adjusting the physical properties of the resulting cured product.
Other oligomers (E) include urethane (meth) acrylate oligomers obtained using polyols other than the polyol component (A1), poly (meth) acrylates of polyoxyalkylene polyols, poly (meth) acrylates of polyester polyols, and the like. Can be mentioned.

(Other monomer (F))
The curable resin composition of the present invention is a monomer (F) ((meth) acrylate other than the monomer (B) and the monomer (C) for the purpose of adjusting the physical properties of the resulting cured product. Etc.) may be included in a small amount. Examples of the other monomer (F) include poly (meth) acrylate of polyhydric alcohol.

  However, when manufacturing a transparent laminated body by the pressure reduction laminating method mentioned later, it is not preferable that curable resin composition contains a low boiling-point compound. In the method of injecting and curing a liquid curable resin composition between a pair of transparent substrates sealed at the periphery, even when injecting with a reduced pressure between the transparent substrates, it is exposed to a reduced pressure at the time of injection. Since the surface area of the curable resin composition is narrow and the degree of vacuum need not be so high, volatilization is a problem even if the curable resin composition contains a compound having a relatively low boiling point. There are few. On the other hand, in the reduced pressure laminating method, the curable resin composition is exposed to reduced pressure in a state where the curable resin composition spreads over almost the entire surface excluding the peripheral portion of the transparent substrate. Therefore, if the curable resin composition contains a low boiling point compound The disappearance due to volatilization is severe, and the composition of the curable resin composition may change greatly. In addition, it becomes difficult to maintain a reduced pressure atmosphere at a required reduced pressure level due to volatilization of volatile compounds.

  Components that tend to have a low boiling point in the curable resin composition are mainly monomers. The monomer (B) is a hydroxyalkyl (meth) acrylate and has a sufficiently high boiling point. Further, the monomer (C) has a higher boiling point than the alkyl group having a large number of carbon atoms, even if it is an alkyl (meth) acrylate. Alkyl (meth) acrylates having a low carbon number of the alkyl group often have a low boiling point, and the curable resin composition containing such a low boiling point alkyl (meth) acrylate as another monomer (F) is: It cannot be used as a curable resin composition for producing a transparent laminate by a reduced pressure lamination method. The curable resin composition that can be used in the reduced pressure lamination method preferably does not contain a monomer having a normal pressure boiling point of 150 ° C. or lower, preferably 200 ° C. or lower.

(Additive (G))
Examples of the additive (G) include ultraviolet absorbers (benzotriazoles, hydroxyphenyltriazines, etc.), light stabilizers (hindered amines, etc.), pigments, dyes, metal oxide fine particles, fillers, and the like.

(Viscosity of curable resin composition)
Of the present invention, the viscosity of the curable resin composition used in the method for producing a transparent laminate, likewise the viscosity of the curable resin composition of the present invention that can be used in other applications, the viscosity V ₄₀ at 40 ° C. It is preferably 50 Pa · s or less. The viscosity V ₂₅ at 25 ° C. is preferably 0.05 Pa · s or more.
The viscosity is measured using an E-type viscometer (manufactured by Toki Sangyo Co., Ltd., RE-85U). However, when the viscosity of the curable resin composition is 100 Pa · s or less, 1 ° 34 ′ × R24 is used as the rotor, and when the viscosity is higher than that, 3 ° × R9.7 is used as the rotor.

When the viscosity V ₄₀ exceeds 50 Pa · s, the fluidity is lowered, and even if it is used in the vacuum lamination method described later, bubbles that are difficult to disappear are easily generated in the curable resin composition. However, when the curable resin composition is used for an application in which a solvent can be used, the solvent is added to increase fluidity to perform application, etc., and then the curable resin composition obtained by removing the solvent is cured. Can be made. In order to make V ₂₅ of the curable resin composition less than 0.05 Pa · s, a large amount of low molecular weight monomer is usually required, and thus the physical properties of the cured product are likely to be lowered. In addition, since a low molecular weight monomer usually has a low boiling point, it is likely to be difficult to use in a reduced pressure laminating method described later.

  In the curable resin composition used in the method for producing the transparent laminate of the present invention described above, the specific unsaturated urethane oligomer (A) obtained by using the specific polyol component (A1) described above. ) And a specific monomer (B), and when the composition is cured, a cured product having good transparency, excellent adhesion to a transparent substrate and tear resistance, and Become.

<Transparent laminate>
The transparent laminate of the present invention has a pair of transparent substrates and a cured resin layer sandwiched between the transparent substrates.

Examples of the transparent substrate include a glass plate or a resin plate. If a glass plate is used, a laminated glass is obtained. If a polycarbonate plate is used as the resin plate, a transparent panel having a high impact property and a light weight can be obtained. Further, a glass plate and a resin plate may be used in combination.
The size of the transparent substrate is not particularly limited, but can be widely used as a transparent member to be installed in an opening for a building or a vehicle if it is a transparent substrate having at least one side of 300 mm or more, more preferably 600 mm or more. . In normal applications, a size of 4 m ² or less is appropriate.

The cured resin layer is a layer made of a cured product of the curable resin composition of the present invention.
The thickness of the cured resin layer is preferably 0.2 to 4.0 mm. When the thickness of the cured resin layer is 0.2 mm or more, the mechanical strength of the transparent laminate is good.

  In the transparent laminate of the present invention described above, since the cured resin layer sandwiched between the transparent substrates is made of a cured product of the curable resin composition of the present invention, the transparency is good and the transparent Excellent adhesion between the substrate and the cured resin layer and tear resistance of the cured resin layer.

<Method for producing transparent laminate>
The transparent laminate of the present invention can be produced by a known production method (for example, a method in which a curable resin composition is sandwiched between a pair of transparent substrates and the curable resin composition is cured), and the pressure is reduced. It is preferable to manufacture by the manufacturing method by a lamination method. The decompression lamination method itself is described in International Publication No. 08/081838 pamphlet and International Publication No. 09/016943 pamphlet.

  The feature of the reduced pressure lamination method is that a curable resin composition layer is formed on one transparent substrate, and another transparent substrate is stacked on the curable resin composition layer in a reduced pressure atmosphere. The curable resin composition is hermetically sealed between the transparent substrates and then placed in a pressure atmosphere (usually an atmospheric pressure atmosphere) higher than the reduced-pressure atmosphere to cure the curable resin composition. For this reason, the manufacturing method of the transparent laminated body of this invention makes the following 1st process and 2nd process essential.

1st process: The said hardening which formed the sealed space which accommodated the curable resin composition inside between a pair of transparent substrates in a pressure-reduced atmosphere, and was sealed between a pair of transparent substrates and this pair of transparent substrates. The process of manufacturing the lamination | stacking precursor which has a conductive resin composition.
2nd process: The process of putting the said lamination | stacking precursor in the atmosphere whose pressure is higher than the said pressure reduction atmosphere, and hardening the said curable resin composition in the atmosphere.

The reduced pressure atmosphere in the first step is preferably a pressure atmosphere of 1 kPa or less, and more preferably a pressure atmosphere of 100 Pa or less. Further, if the pressure in the reduced-pressure atmosphere is too low, the curable resin composition such as a monomer may be volatilized. Therefore, the reduced-pressure atmosphere is preferably a pressure atmosphere of 1 Pa or more, and more preferably a pressure atmosphere of 10 Pa or more. .
In the second step, the atmosphere having a pressure higher than that of the reduced pressure atmosphere is preferably a pressure atmosphere of 50 kPa or more, and more preferably a pressure atmosphere of 100 kPa or more. The pressure atmosphere in the second step is usually an atmospheric pressure atmosphere. Hereinafter, this manufacturing method will be described by taking as an example the case where the atmosphere having a higher pressure than the above-described reduced-pressure atmosphere is an atmospheric pressure atmosphere.

In the first step, even if bubbles remain in the curable resin composition in the sealed space, the bubbles are likely to disappear before the curable resin composition is cured, and a cured resin layer having no bubbles is easily obtained. .
When the laminated precursor formed in the first step is placed under atmospheric pressure, pressure is also applied to the curable resin composition in the sealed space due to the pressure from the transparent substrate under atmospheric pressure. On the other hand, since the inside of the bubbles in the curable resin composition is at the reduced-pressure atmospheric pressure in the first step, the volume of the bubbles is reduced by the pressure applied to the curable resin composition in the second step. When this gas dissolves in the curable resin composition, the bubbles disappear. In order to eliminate bubbles, it is preferable to hold the lamination precursor under atmospheric pressure for a while before the curable resin composition is cured. The holding time is preferably 5 minutes or more, but the holding time may be shorter when there are no bubbles or when the bubbles are very small and quickly disappear.

  In the first step, the reduced-pressure atmosphere is required at the stage of forming the sealed space, and is not required at the previous stage. For example, a sealing material having a predetermined thickness is provided around the entire periphery of one surface of one transparent substrate, and the curable resin composition is supplied to the transparent substrate surface surrounded by the sealing material. These layers can be formed in an atmospheric pressure atmosphere at these stages. The sealed space is preferably formed as follows.

  The transparent substrate having the layer of the curable resin composition obtained above and the other transparent substrate are put in a reduced pressure chamber to have a predetermined arrangement. That is, the transparent substrate having the layer of the curable resin composition is placed on a horizontal surface plate with the layer of the curable resin composition facing up, and the other transparent substrate is mounted on the tip of a cylinder that can be moved up and down. It attaches to the lower surface of a surface plate, and both transparent substrates are located in parallel, without the layer of curable resin composition contacting the other transparent substrate. Thereafter, the decompression chamber is closed and evacuated, and the inside of the decompression chamber is set to a predetermined decompressed atmosphere. After the inside of the decompression chamber becomes a predetermined decompression atmosphere, the cylinder is operated and both transparent substrates are overlapped via the layer of the curable resin composition, and the curable resin is placed in the space surrounded by the both transparent substrates and the sealing material. The composition is sealed to form a laminated precursor. After forming the lamination precursor, the atmosphere inside the decompression chamber is returned to the atmospheric pressure, and the lamination precursor is taken out from the decompression chamber.

  The adhesion strength between the transparent substrates and the sealing material may be such that no gas enters from the interface between the transparent substrate and the sealing material when the lamination precursor is placed under atmospheric pressure. For example, a layer of a pressure sensitive adhesive can be provided on the surface of the sealing material so that the transparent substrate and the sealing material can be brought into close contact with each other. If necessary, a curable adhesive is provided at the interface between the transparent substrate and the sealing material, or the sealing material is formed of a curable resin to form a laminated precursor, and then in the vacuum chamber or from the vacuum chamber. After taking out, these adhesives and curable resin can be hardened, and the adhesive strength of a transparent substrate and a sealing material can be improved.

  The second step is a step of curing the curable resin composition under atmospheric pressure with the lamination precursor. When the curable resin composition is a thermosetting curable resin, it is thermoset. More preferably, a photocurable resin composition is used as the curable resin composition and photocured. Photocuring can be performed by irradiating light from a light source such as an ultraviolet lamp through a transparent substrate. As described above, it is preferable to harden the curable resin composition after holding the laminated precursor for a while under atmospheric pressure. By curing the curable resin composition, the curable resin composition becomes a cured resin, and the transparent laminate as described above is obtained.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited only to these examples.
Examples 1 to 9 are examples, and examples 10 to 13 are comparative examples.

(Haze value)
The haze value was measured as an evaluation of the transparency of the portion where the cured resin layer of the transparent laminate was present. The haze value was measured according to ASTM D1003 using Hazeguard II (manufactured by Toyo Seiki Seisakusho).

(Adhesion)
A part of one transparent substrate of the transparent laminate is removed to expose the cured resin layer, and a cured resin layer having a length of 30 mm and a width of 10 mm in close contact with the other transparent substrate is used as a test piece. The adhesion strength when peeling off from the transparent substrate leaving a length of 10 mm was measured using a bond tester (SS-15KP, manufactured by SESHIN) as a tester, measuring temperature: 25 ° C., relative humidity: 50%, between marked lines : 20 mm, tensile speed: 50 mm / min.

(Tear resistance)
A part of one transparent substrate of the transparent laminate is removed to expose the cured resin layer, and a part (approximately 10 mm × 30 mm in size) of the cured resin layer is peeled off from the other transparent substrate. It was. The operation of making a tear of about 1 mm in the center of the long side of the obtained test piece was performed using a bond tester (SESSIN, SS-15KP), measurement temperature: 25 ° C., relative humidity: 50%, standard The distance between the lines was 20 mm, and the tensile speed was 50 mm / min. The resistance when the resin was broken by stress from above and below was measured as the strength.
Further, as an index of flexibility, strain at break (hereinafter referred to as break strain) was measured.

(viscosity)
The viscosity V ₂₅ at 25 ° C. of the curable composition was measured using an E-type viscometer (manufactured by Toki Sangyo Co., Ltd., RE-85U). However, when the viscosity of the composition was 100 Pa · s or less, 1 ° 34 ′ × R24 was used as the rotor, and when the viscosity was higher than that, 3 ° × R9.7 was used as the rotor.

(Polyol (c-1))
Zinc hexacyanocobaltate-glyme complex was used as a catalyst, propylene oxide was reacted with the initiator, and then ethylene oxide was reacted. After deactivating the catalyst, purification was performed to obtain a polyol (c-1) shown in Table 1.

(Polyol (c-2))
Zinc hexacyanocobaltate-glyme complex was used as a catalyst, and propylene oxide was reacted with the initiator. After deactivating the catalyst, purification was performed to obtain a polyol (c-2) shown in Table 1.

(Polyol (d-1))
Zinc hexacyanocobaltate-tert-butanol complex was used as a catalyst, and propylene oxide was reacted with the initiator. After deactivating the catalyst, purification was performed to obtain a polyol (d-1) shown in Table 1.

(Polyol (d-2))
Ethylene glycol (polyol (d-2)) manufactured by Junsei Chemical Co., Ltd. was prepared.

(Polyol (d-3))
Glycerin (polyol (d-3)) manufactured by Kanto Chemical Co., Inc. was prepared.

(Polyol components (b-1) to (b-4), (b-7))
In the molar ratio shown in Table 2, polyol (c-1) and polyols (d-1) to (d-3) are mixed, and polyol components (b-1) to (b-4) and (b-7) are mixed. )

(Polyol component (b-5), (b-6))
Polyol components (b-5) and (b-6) were respectively used by using polyols (c-1) and (c-2) alone.

[Example 1]
To 100 parts by mass (0.05 mol) of the polyol component (b-1), 13.2 parts by mass (0.06 mol) of isophorone diisocyanate (hereinafter referred to as IPDI) is added, and dibutyltin dilaurate (hereinafter DBTDL). In the presence of 0.01 part by mass of (A), the reaction was carried out at 80 ° C. for 4 hours to obtain a urethane prepolymer. To the urethane prepolymer, 0.05 part by mass of DBTDL and 0.05 part by mass of hydroquinone monomethyl ether (hereinafter referred to as HQME) are added, and 2-hydroxyethyl acrylate (hereinafter referred to as HEA) at 50 ° C. 2.4 parts by mass (0.02 mol) was added, stirred at 60 ° C., and the reaction was performed until the isocyanate group disappeared while measuring the isocyanate group content by NCO titration according to JIS K1603-1. The urethane acrylate oligomer (oligomer (e-1)) was obtained.

  40 parts by mass of oligomer (e-1), 40 parts by mass of 2-hydroxybutyl methacrylate (hereinafter referred to as HBMA), and 20 parts by mass of n-dodecyl methacrylate (hereinafter referred to as DMA) were mixed. 1 part by mass of -hydroxycyclohexyl phenyl ketone (hereinafter referred to as HCHPK) was added to prepare a photocurable resin composition.

[Example 2]
To 150 parts by mass (0.05 mol) of the polyol component (b-2), 14.4 parts by mass (0.065 mol) of IPDI is added, and in the presence of 0.01 part by mass of DBTDL, at 80 ° C. for 4 hours. It was made to react and the urethane prepolymer was obtained. To the urethane prepolymer, 0.05 part by mass of DBTDL and 0.05 part by mass of HQME are added, and 3.5 parts by mass (0.03 mol) of HEA is added at 50 ° C., and the mixture is stirred at 60 ° C. While measuring the isocyanate group content by NCO titration according to K1603-1, the reaction was carried out until the isocyanate group disappeared to obtain a urethane acrylate oligomer (oligomer (e-2)).
40 parts by mass of the oligomer (e-2), 40 parts by mass of HBMA, and 20 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 3]
A photocurable resin composition was prepared in the same manner as in Example 2 except that the polyol component (b-3) was used instead of the polyol component (b-2).

[Example 4]
A photocurable resin composition was prepared in the same manner as in Example 2 except that the polyol component (b-4) was used instead of the polyol component (b-2).

[Example 5]
To 167 parts by mass (0.05 mol) of the polyol component (b-4), 10.1 parts by mass (0.06 mol) of hexamethylene diisocyanate (hereinafter referred to as HDI) is added, and 0.01 parts by mass of DBTDL is added. In the presence of parts, the reaction was carried out at 80 ° C. for 4 hours to obtain a urethane prepolymer. 0.05 parts by mass of DBTDL and 0.05 parts by mass of HQME are added to the urethane prepolymer, 2.3 parts by mass (0.02 mol) of HEA is added at 50 ° C., and the mixture is stirred at 60 ° C. While measuring the isocyanate group content by NCO titration according to K1603-1, the reaction was carried out until the isocyanate group disappeared to obtain a urethane acrylate oligomer (oligomer (e-5)).
40 parts by mass of the oligomer (e-5), 40 parts by mass of HBMA, and 20 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 6]
30 parts by mass of the oligomer (e-1), 30 parts by mass of HBMA, and 40 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 7]
30 parts by mass of the oligomer (e-1), 50 parts by mass of HBMA, and 20 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 8]
50 parts by mass of the oligomer (e-1), 40 parts by mass of HBMA, and 10 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 9]
40 parts by mass of oligomer (e-1), 40 parts by mass of 2-hydroxypropyl methacrylate (hereinafter referred to as HPMA) and 20 parts by mass of DMA are mixed, 1 part by mass of HCHPK is added, and a photocurable resin is added. A composition was prepared.

[Example 10]
To 200 parts by mass (0.05 mol) of the polyol component (b-5), 10.9 parts by mass (0.065 mol) of HDI was added, and in the presence of 0.01 part by mass of DBTDL, at 80 ° C. for 4 hours. It was made to react and the urethane prepolymer was obtained. To the urethane prepolymer, 0.05 part by mass of DBTDL and 0.05 part by mass of HQME are added, and 3.5 parts by mass (0.03 mol) of HEA is added at 50 ° C., and the mixture is stirred at 60 ° C. While measuring the isocyanate group content by NCO titration according to K1603-1, the reaction was carried out until the isocyanate group disappeared to obtain a urethane acrylate oligomer (oligomer (e-6)).
40 parts by mass of oligomer (e-6), 40 parts by mass of HBMA, and 20 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 11]
To 200 parts by mass (0.05 mol) of the polyol component (b-5), 13.3 parts by mass (0.06 mol) of IPDI was added, and in the presence of 0.01 part by mass of DBTDL, at 80 ° C. for 4 hours. It was made to react and the urethane prepolymer was obtained. 0.05 parts by mass of DBTDL and 0.05 parts by mass of HQME are added to the urethane prepolymer, 2.3 parts by mass (0.02 mol) of HEA is added at 50 ° C., and the mixture is stirred at 60 ° C. While measuring the isocyanate group content by NCO titration in accordance with K1603-1, the reaction was carried out until the isocyanate group disappeared to obtain a urethane acrylate oligomer (oligomer (e-7)).
40 parts by mass of the oligomer (e-7), 40 parts by mass of HBMA, and 20 parts by mass of DMA were mixed, and 1 part by mass of HCHPK was added to prepare a photocurable resin composition.

[Example 12]
A photocurable resin composition was prepared in the same manner as in Example 2 except that the polyol component (b-6) was used instead of the polyol component (b-2).

[Example 13]
A photocurable resin composition was prepared in the same manner as in Example 2 except that the polyol component (b-7) was used instead of the polyol component (b-2).

(Manufacture of laminates)
Laminated glass (transparent laminated body) was manufactured using each curable resin composition obtained in Examples 1-13. A manufacturing method will be described with reference to FIG.
Each curable resin composition was stored in a vacuum chamber in an open state while being put in a container, and was used after defoaming by reducing the pressure in the vacuum chamber to about 200 Pa · s and holding for 10 minutes. .

  As a transparent substrate, two soda lime glasses having a length of 610 mm, a width of 610 mm, and a thickness of 2 mm were prepared. After sticking a double-sided adhesive tape (seal material) having a thickness of 1 mm and a width of 10 mm along the edges of the four sides of one transparent substrate, the release film on the upper surface of the double-sided adhesive tape was removed.

A UV curable resin for sealing prepared by uniformly mixing 100 parts by mass of urethane acrylate oligomer (manufactured by Kyoeisha Chemical Co., Ltd., UF8001G) and 1 part by mass of benzoin isopropyl ether (polymerization initiator) in advance is used for the double-sided adhesive tape. The upper surface was coated with a dispenser with a coating thickness of about 0.3 mm to form an ultraviolet curable resin layer for sealing.
The curable resin composition was dropped at a plurality of locations using a dispenser in a region surrounded by the double-sided adhesive tape on the surface of the transparent substrate on which the double-sided adhesive tape was applied, so that the total mass was 380 g.

As shown in FIG. 1, the transparent substrate 10 in which the curable resin composition 14 was dropped in a region surrounded by the double-sided adhesive tape 12 (sealing material) was placed horizontally in the decompression chamber 26.
The other transparent substrate 16 is held on the upper surface plate 30 in the decompression chamber 26 by using the suction pad 32 and is held in parallel with the transparent substrate 10 so that the distance from the transparent substrate 10 is 10 mm. I let you.

The decompression chamber 26 was sealed, and the vacuum pump 28 was operated to evacuate the interior of the decompression chamber 26 to about 30 Pa. At this time, foaming of the curable resin composition 14 did not continue.
The upper platen 30 was lowered by the cylinder 34, and the transparent substrate 10 and the transparent substrate 16 were pressure-bonded with a pressure of 2 kPa and held for 1 minute.
The inside of the decompression chamber 26 was returned to atmospheric pressure in about 30 seconds, and a laminated precursor in which the transparent substrate 10 and the transparent substrate 16 were in close contact with each other through the uncured layer of the curable resin composition 14 was obtained.

The upper surface plate 30 was raised by the cylinder 34, and the laminated precursor adhered to the suction pad 32 of the upper surface plate 30 was peeled from the upper surface plate 30.
The portion where the double-sided adhesive tape 12 on the outer periphery of the laminated precursor is present is irradiated with ultraviolet rays from a fiber light source using a high-pressure mercury lamp as a light source through a transparent substrate 16, and UV curing for sealing the upper surface of the double-sided adhesive tape 12 Resin 36 was cured. Thereafter, the laminated precursor was kept horizontal and allowed to stand for about 1 hour.

A transparent laminate (laminated glass) is obtained by curing the curable resin composition 14 by irradiating ultraviolet rays having an intensity of 1 mW / cm ² for 10 minutes uniformly from both sides of the laminate precursor with a high-pressure mercury lamp. Obtained. The evaluation results of the transparent laminate are shown in Table 3.

  As shown in the results of Table 3, in Examples 1 to 9 according to the present invention, a transparent curable composition having a haze value of 1.0% or less was obtained. Further, both the adhesion to the substrate and the tear resistance were good. In Examples 1 to 9 according to the present invention, it was possible to obtain a transparent laminate having a good balance of transparency, adhesion to a substrate, and tear resistance. Particularly in Example 1, the adhesion and strength were significantly improved, and a transparent laminate suitable for laminated glass was obtained.

In Examples 10 and 11, since the polyol component (A1) did not contain the polyol (a2), the adhesion was inferior. In Example 10, the tear resistance strength was slightly inferior.
Since Example 12 contains only a polyol having a large hydroxyl value, the tear resistance fracture strain was low and the flexibility was poor. Moreover, the adhesiveness was also inferior.
In Example 13, the viscosity of the curable resin composition was high, and a transparent laminate could not be produced.

  The curable resin composition of the present invention is useful as a raw material for the adhesive resin layer of laminated glass, and the transparent laminate of the present invention is laminated glass (windshield glass, safety glass, security glass, etc.), for display, It is useful for solar cell modules.

DESCRIPTION OF SYMBOLS 10 Transparent substrate 12 Double-sided adhesive tape 14 Curable resin composition 16 Transparent substrate 26 Depressurization chamber 28 Vacuum pump 30 Top plate 32 Adsorption pad 34 Cylinder 36 UV curable resin for sealing

Claims (6)

A curable resin composition for producing a transparent laminate, which is used in a method for producing a transparent laminate by curing a curable resin composition sandwiched between a pair of transparent substrates,
The following unsaturated urethane oligomer (A), viewed contains the following monomer (B), and the following monomer (C),
In 100% by mass of the curable resin composition for producing a transparent laminate, the proportion of the unsaturated urethane oligomer (A) is 20 to 60% by mass, and the proportion of the monomer (B) is 25 to 50% by mass. A curable resin composition for producing a transparent laminate , wherein the ratio of the monomer (C) is 3 to 50% by mass .
Unsaturated urethane oligomer (A): The following polyol component (A1) and polyisocyanate (A2) are reacted at a ratio of isocyanate group: hydroxyl molar ratio of 1.2: 1 to 3: 1 to give an isocyanate group-terminated urethane. A reaction product obtained by reacting an isocyanate group-terminated urethane prepolymer with the unsaturated hydroxy compound (A3) described below at a ratio such that the molar ratio of isocyanate group: hydroxyl group is 1: 1 to 1: 1.5 . An unsaturated urethane oligomer having an average of 2 to 4 curable functional groups per molecule.
Polyol component (A1): A polyol component containing the following polyol (a1) and 0.5 to 2 mol of the following polyol (a2) with respect to 1 mol of the polyol (a1).
Polyol (a1): A polyoxyalkylene polyol having a hydroxyl value of 15 to 40 mgKOH / g, obtained by reacting an initiator having 2 active hydrogen atoms with monoepoxide.
Polyol (a2): a polyoxyalkylene polyol obtained by reacting an initiator having 2 or 3 active hydrogens with monoepoxide, or a polyhydric alcohol having 2 or 3 hydroxyl groups, and having a hydroxyl value of 55 to 1 , 830 mg KOH / g polyol.
Unsaturated hydroxy compound (A3): A compound having the following curable functional group and hydroxyl group.
Curable functional group: a group represented by CH ₂ ═C (R) C (O) O— (wherein R represents a hydrogen atom or a methyl group).
Monomer (B): Compound represented by CH ₂ ═C (R) C (O) O—R ² (wherein R represents a hydrogen atom or a methyl group, R ² has 1 to ² hydroxyl groups) And represents a hydroxyalkyl group having 3 to 4 carbon atoms).
Monomer (C): a compound represented by CH ₂ ═C (R) C (O) O—R ³ (wherein R represents a hydrogen atom or a methyl group, and R ³ has 8 to 22 carbon atoms) Represents an alkyl group). Further comprising a photopolymerization initiator (D), transparent laminate for producing a curable resin composition according to claim 1. A transparent laminate having a pair of transparent substrates and a layer of cured resin sandwiched between the transparent substrates,
The transparent laminated body whose said cured resin is a hardened | cured material of the curable resin composition for transparent laminated body manufacture of Claim 1 or 2 . In a reduced-pressure atmosphere, a sealed space containing the curable resin composition for producing a transparent laminate according to claim 1 is formed between the pair of transparent substrates, and the pair of transparent substrates and the pair of transparent substrates are formed. A first step of producing a lamination precursor having the curable resin composition for producing a transparent laminate sealed between transparent substrates;
A method for producing a transparent laminate , comprising: placing the laminate precursor in an atmosphere having a pressure higher than the reduced-pressure atmosphere, and curing the curable resin composition for producing the transparent laminate in the atmosphere. . The manufacturing method of the transparent laminated body of Claim 4 whose said pressure reduction atmosphere is a pressure atmosphere of 100 Pa or less, and an atmosphere whose pressure is higher than the said pressure reduction atmosphere is an atmospheric pressure atmosphere. The curable resin composition for producing a transparent laminate is a photocurable resin composition, and in the second step, the laminate precursor is irradiated with light to cure the curable resin composition for producing a transparent laminate . The manufacturing method of the transparent laminated body of Claim 4 or 5 .

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