JP6899225B2 - Active energy ray-curable composition - Google Patents

Description

The present invention provides an active energy ray-curable composition that can be used as an interlayer filler for a transparent substrate for a display such as a personal computer, a television, and a mobile phone, and a cured product layer of the active energy ray-curable composition. Regarding the laminated body to have.

The displays used in personal computers, car navigation systems, televisions, mobile phones, etc. project images with the light from the backlight. Various transparent base materials such as glass base materials such as glass plates and plastic base materials such as plastic films are used for displays, including color filters, and due to the influence of light scattering and absorption of these transparent base materials. , The amount of light output from the light source to the outside of the display is reduced. If the amount of decrease becomes large, the screen becomes dark and the visibility is lowered. In order to improve visibility, measures are taken such as improving the antireflection property of the display surface layer and increasing the amount of light from the light source.

As a part of this, there is a method of changing the air layer between transparent substrates such as a glass substrate and a plastic substrate into a resin layer. By changing the air layer to a resin layer, it is possible to prevent light scattering at the interface between the air and the glass base material or the plastic base material, so that it is possible to prevent a decrease in the amount of output light.

The performance required for resins used between layers of transparent substrates such as glass substrates and plastic substrates is not only adhesion to transparent substrates, but also high deformation resistance, high flexibility, and high transparency. In particular, the transmittance at 400 nm is required to be 95% or more. Further, it is necessary that the resistance under high temperature, specifically, that there is no shape change or no hue change at 95 ° C. Aiming at a resin having such performance, urethane (meth) acrylate using an olefin skeleton and a composition containing these have been proposed in the following prior documents.

Japanese Patent No. 1041553 Japanese Patent No. 2582575 Japanese Unexamined Patent Publication No. 2002-069138 JP-A-2002-309185 Japanese Unexamined Patent Publication No. 2003-155455 Japanese Unexamined Patent Publication No. 2010-144000 JP-A-2010-254890 JP-A-2010-254891 Japanese Unexamined Patent Publication No. 2010-265402 Japanese Unexamined Patent Publication No. 2011-116965

These prior documents report on urethane (meth) acrylates containing a hydrogenated material such as a hydrogenated polyolefin polyol as a constituent, and compositions containing the same. The use of a hydrogenated material as a constituent component of urethane (meth) acrylate is very effective from the viewpoint of preventing deterioration of the cured product due to oxidation. However, since the urethane (meth) acrylate has a high hydrophobicity, the compatibility with other components (for example, bifunctional or higher functional (meth) acrylate) that can be contained in the composition tends to be poor. .. Therefore, when using the urethane (meth) acrylate, it is difficult to adjust the viscosity of the composition and to impart the desired properties (for example, hardness, deformation resistance, flexibility) to the cured product. there were.

Further, the urethane (meth) acrylates described in these prior documents have a high viscosity and have a drawback that they cannot be produced on a large scale. In addition, these urethane (meth) acrylates and their compositions have the drawback of becoming cloudy at low temperatures and reducing transparency, and the drawback of low heat resistance of the cured product, that is, the cured product turns yellow at high temperatures. There were drawbacks such as squeezing and changing shape. Therefore, it is insufficient as an interlayer filler for a display base material.

Further, the base material for smartphones and tablets is required to be thinned, and as an interlayer filler, further reduction in curing shrinkage is required. Further, with the generalization of the usage environment, it is required to further improve the heat resistance of the cured product and the adhesion to the transparent substrate.

Therefore, an object of the present invention is to provide a urethane (meth) acrylate having high compatibility with components that can be contained in the composition and having a low viscosity, and the cured product having good oxidation resistance, transparency, and heat resistance. It is an object of the present invention to provide the active energy ray-curable composition shown and a laminate having a cured product layer of the active energy ray-curable composition.

As a result of diligent studies to achieve the above object, the present inventor has obtained urethane (meth) acrylate, monofunctional (meth) acrylate, which is a reaction product of a specific urethane prepolymer and a (meth) acrylate having a hydroxyl group. And it has been found that an active energy ray-curable composition containing a photopolymerization initiator is useful as a curable composition for interlayer filling of a transparent base material such as a glass base material or a plastic base material.

That is, the present invention relates to a urethane (meth) acrylate (X), which is a reaction product of a urethane prepolymer having an isocyanate group and a (meth) acrylate (C) having a hydroxyl group.
An active energy ray-curable composition containing a monofunctional (meth) acrylate (Y) and a photopolymerization initiator (Z).
The urethane prepolymer is a urethane prepolymer containing a polyol (A) and a polyisocyanate (B) as constituent components.
The polyol (A) is a polyol containing 50% by weight or more of hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000.
Provided is an active energy ray-curable composition, wherein the polyisocyanate (B) is a polyisocyanate containing 50% by weight or more of an aliphatic diisocyanate.

Further, the active energy ray-curable composition preferably further contains a bifunctional or higher functional (meth) acrylate.

Further, the active energy ray-curable composition is preferably for interlayer filling.

In the present invention, the cured product layer of the active energy ray-curable composition is formed between the first transparent base material selected from glass and plastic and the second transparent base material selected from glass and plastic. The laminated body having is also described.

The urethane (meth) acrylate (X) in the active energy ray-curable composition of the present invention does not become highly viscous during its production, has few by-products of by-products, and can be contained in the composition. Highly compatible with components (for example, bifunctional or higher functional acrylic monomers). Therefore, the active energy ray-curable composition of the present invention does not deteriorate the appearance of the resin due to cloudiness at a low temperature, and its viscosity can be easily adjusted. Further, the cured product of the present invention has good oxidation resistance, transparency, and heat resistance. Further, since the compatibility is high as described above, it is possible to realize the characteristics of the desired cured product (for example, hardness, deformation resistance, flexibility, etc.). Further, when the active energy ray-curable composition of the present invention is used as an interlayer filler, the adhesion retention between the cured product and the substrate is good.

Further, by filling the active energy ray-curable composition of the present invention between the transparent substrates of a display used in a personal computer, a car navigation system, a television, a mobile phone (smartphone, etc.), a tablet, etc., the air and the transparent substrate are filled. It is useful in that it can prevent light scattering at the interface and can obtain a laminate that is less likely to cause hue change or shape change during the heat resistance test.

It is the schematic which shows one aspect of the laminated body of this invention. It is the schematic which shows the mode of the glass laminate used in this Example. It is the schematic which shows the mode of the glass laminate used in this Example. In the figure, (A) is a view of the glass laminate from above, and (B) is a view of the glass laminate from the side.

<Active energy ray-curable composition>
The active energy ray-curable composition of the present invention is a reaction product of a urethane prepolymer having an isocyanate group and a (meth) acrylate (C) having a hydroxyl group, urethane (meth) acrylate (X), monofunctional (meth). An active energy ray-curable composition containing an acrylate (Y) and a photopolymerization initiator (Z), wherein the urethane prepolymer contains a polyol (A) and a polyisocyanate (B) as constituent components. The polyol (A) is a prepolymer and contains 50% by weight or more of a hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000, and the polyisocyanate (B) contains 50% by weight of an aliphatic diisocyanate. It is characterized by being a polyisocyanate containing% or more.

The urethane prepolymer containing the isocyanate group is referred to as "urethane prepolymer", the polyol (A) is referred to as "(A)", and the polyisocyanate (B) is referred to as "(B)". The (meth) acrylate (C) having a hydroxyl group of is "(meth) acrylate (C)" or "(C)", and the alcohol (D) having one hydroxyl group described later is "alcohol (D)" or "( "D)", the monofunctional (meth) acrylate (Y) described above as "(meth) acrylate (Y)" or "(Y)", and the photopolymerization initiator (Z) described below simply as "(Z)". May be called.

[Urethane (meth) acrylate (X)]
The urethane (meth) acrylate (X) of the present invention is a reaction product of a urethane prepolymer and a (meth) acrylate (C), and the urethane prepolymer is a polyol (A) and a polyisocyanate (polyisocyanate) as constituent components. The polyol (A) containing B) is a polyol containing 50% by weight or more of a hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000, and the polyisocyanate (B) contains 50 aliphatic diisocyanates. It is a polyisocyanate containing% by weight or more. The urethane (meth) acrylate (X) of the present invention may be a reaction product of the urethane prepolymer and the (meth) acrylate (C) and the alcohol (D).

The weight average molecular weight (Mw) of the urethane (meth) acrylate (X) is not particularly limited, but is preferably 8000 to 20000, more preferably 1000 to 18000, for example. If the weight average molecular weight is less than 8000, the flexibility tends to decrease and the appearance of the resin tends to deteriorate. On the other hand, when the weight average molecular weight exceeds 20000, the compatibility of the obtained urethane (meth) acrylate tends to deteriorate. The "weight average molecular weight" in the present invention is a polystyrene-equivalent value measured by GPC.

[Polyprethane (A)]
The polyol (A) in the present invention is not particularly limited as long as it is a polyol containing 50% by weight or more of hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000. Two or more types of polyols may be used in combination depending on the purpose.

The weight average molecular weight (Mw) of the hydrogenated dimerdiol is not particularly limited as long as it is in the range of 200 to 1000, but is preferably 300 to 800. When the weight average molecular weight is less than 200, the Tg of the urethane (meth) acrylate becomes high, the flexibility is lowered, the resin appearance is deteriorated, and the by-products tend to increase. On the other hand, when the weight average molecular weight exceeds 1000, the compatibility of the obtained urethane (meth) acrylate tends to deteriorate.

Hydrogenated dimerdiol is obtained by reducing at least one of hydrogenated dimer acid, hydrogenated dimer acid, and a lower alcohol ester thereof in the presence of a catalyst, and the carboxylic acid or carboxylate portion of dimer acid is used as an alcohol, and carbon- is used as a raw material. When it has a carbon double bond, it is mainly composed of a diol obtained by hydrogenating the double bond. For example, the structure of the main component of the hydrogenated dimerdiol can be represented by the following formulas (1) and (2).

In the formula, both R ¹ and R ² are alkyl groups, and the total number of carbon atoms, a and b contained in ^{R 1} and R ^{2 is 30.}

In the formula, R ³ and R ⁴ are both alkyl groups, and the total number of carbon atoms, c and d contained in ^{R 3} and R ^{4 is 34.}

As the hydrogenated dimer diol having a weight average molecular weight of 200 to 1000, a commercially available product may be used, and examples thereof include "Pripole 2033" and "Pripole 2030" manufactured by Croda Japan.

Examples of the polyol other than the hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000 that can be contained in the polyol (A) in the present invention include a hydrogenated dimerdiol having a weight average molecular weight of more than 1000, a polyolefin polyol, and a hydrogenated polyolefin. Examples thereof include polyols, polyester polyols, trimethylolpropane, pentaerythritol, glycerin, and modified compounds thereof.

Examples of the hydrogenated dimer diol having a weight average molecular weight of more than 1000 include those having a weight average molecular weight of more than 1000 among the hydrogenated dimer diols described above. The polyolefin polyol is not particularly limited as long as it has a polyolefin skeleton, and examples thereof include polybutadiene polyols and polyisoprene polyols. The hydrogenated polyolefin polyol is not particularly limited as long as it is a polyol having a polyolefin skeleton and is hydrogenated, and examples thereof include hydrogenated polybutadiene polyol and hydrogenated polyisoprene polyol. The hydrogenated polybutadiene polyol is a polyol obtained by hydrogenating a polybutadiene polyol. The hydrogenated polyisoprene polyol is a polyol obtained by hydrogenating a polyisoprene polyol.

Commercially available products may be used as polyols other than hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000. For example, "Preplast 3197" and "Preplast 3199" manufactured by Claude Japan Co., Ltd. and "Trimethylol" manufactured by Mitsubishi Gas Chemical Company Co., Ltd. Propane (TMP) ", Sanyo Kasei Co., Ltd." Sanniks HD-402 (polypropylene glycol modified product of pentaerythritol) "," Sanniks HD-250 (polypropylene glycol modified product of glycerin) ", Idemitsu Kosan Co., Ltd." Epol " , "GI-2000", "GI-3000", "G-3000" manufactured by Nippon Soda Co., Ltd., "KRASOL HLBH P3000", "KRASOL LBH-P2000" manufactured by Nagase Sangyo Co., Ltd. and the like.

In the urethane prepolymer of the present invention, the content of the hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000 as a constituent is not particularly limited as long as it is 50% by weight or more based on the total amount of the polyol (A). From the viewpoint of improving compatibility, 60% by weight or more is preferable, 80% by weight is more preferable, 95% by weight is further preferable, and 99% by weight or more is particularly preferable.

[Polyisocyanate (B)]
The polyisocyanate (B) of the present invention is not particularly limited as long as it is a polyisocyanate containing 50% by weight or more of an aliphatic diisocyanate. Two or more types of polyisocyanate may be used in combination depending on the purpose.

Examples of the aliphatic diisocyanate include an alicyclic diisocyanate, a linear or branched aliphatic diisocyanate, and an aliphatic diisocyanate compound obtained by hydrogenating aromatic isocyanates. The alicyclic diisocyanate is not particularly limited, and examples thereof include isophorone diisocyanate. Examples of the aliphatic diisocyanate include linear aliphatic diisocyanates such as hexamethylene diisocyanate; branched chain aliphatic diisocyanates such as 2,2,4-trimethylhexamethylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate. Can be mentioned. Examples of the diisocyanate compound obtained by hydrogenating the aromatic isocyanates include hydrogenated xylylene diisocyanate and hydrogenated diphenylmethane diisocyanate.

Commercially available products may be used as the aliphatic diisocyanate, for example, "VESTANAT IPDI (isophorone diisocyanate)" manufactured by Evonik, "TMDI (2,2,4-trimethylhexamethylene diisocyanate)", and "HDI (hexa) manufactured by Tosoh Corporation". Methylene diisocyanate) ”and the like.

Examples of the polyisocyanate other than the aliphatic diisocyanate that can be contained in the polyisocyanate (B) include aromatic compounds having two or more isocyanate groups (for example, aromatic diisocyanate, aromatic triisocyanate, aromatic tetraisocyanate, etc.). Examples thereof include aliphatic compounds having 3 or more isocyanate groups (for example, aliphatic tetraisocyanate, aliphatic triisocyanate, etc.).

In the urethane prepolymer of the present invention, the content of the aliphatic diisocyanate as a constituent is not particularly limited as long as it is 50% by weight or more with respect to the total amount of polyisocyanate (B), but 60% by weight or more is preferable, and 80% by weight is preferable. % Is more preferable, 95% by weight is further preferable, and 99% by weight or more is particularly preferable.

[(Meta) Acrylate (C)]
The (meth) acrylate (C) of the present invention is not particularly limited as long as it is a (meth) acrylate having a hydroxyl group, but for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxynormalpropyl (meth) acrylate, 4 -Has one (meth) acryloyl group such as hydroxybutyl (meth) acrylate and further has a (meth) acrylate having a hydroxyl group, and has two or more (meth) acryloyl groups such as pentaallyslitol triacrylate. Further, a (meth) acrylate having a hydroxyl group can be used. Two or more kinds of (meth) acrylate (C) may be used in combination depending on the purpose.

As the (meth) acrylate (C), a commercially available product may be used, and examples thereof include "HEA (2-hydroxyethyl acrylate)" manufactured by Nippon Shokubai Co., Ltd.

[Alcohol (D)]
The alcohol (D) of the present invention is not particularly limited as long as it is an alcohol having one hydroxyl group, but for example, it is an aliphatic or alicyclic primary alcohol having a molecular weight in the range of 70 to 400 and having 3 or more carbon atoms. Alcohol is preferred. The alcohol (D) does not contain (meth) acrylate (C). If the alcohol has less than 3 carbon atoms or a molecular weight of less than 70, it is not preferable because it may volatilize during the production of urethane (meth) acrylate. On the other hand, if the molecular weight exceeds 400, the reactivity with the isocyanate group may decrease and the reaction time may become long, which is not preferable. Further, an alcohol having an aromatic ring is not preferable because the resulting urethane (meth) acrylate (X) may have a high hue and may have poor weather resistance. Two or more kinds of the above alcohols may be used in combination depending on the purpose.

Examples of the alcohol (D) include 1-butanol, 1-heptanol, 1-hexanol, normal octyl alcohol, 2-ethylhexyl alcohol, cyclohexanemethanol, capryl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol (cetyl alcohol), and stearyl alcohol. And a mixture of these. Of these, 2-ethylhexyl alcohol is preferable from the viewpoint of boiling point, price, and availability.

[Manufacturing method of urethane (meth) acrylate (X)]
The urethane (meth) acrylate (X) of the present invention forms a urethane prepolymer by subjecting a polyol (A) and a polyisocyanate (B) to a urethanization reaction, and then the urethane prepolymer and the (meth) acrylate. It can be produced by reacting with (C). When the urethane prepolymer is reacted with the (meth) acrylate (C), the alcohol (D) may be used at the same time as the (meth) acrylate (C). Further, a monofunctional (meth) acrylate (Y) may be used as a compatibilizer when forming a urethane prepolymer (that is, during a urethanization reaction between a polyol component and an isocyanate component).

In the method for producing urethane (meth) acrylate (X) of the present invention, for example, "a method of collectively mixing and reacting (A), (B), and (C)" and "reacting (B) and (C)" Compared with conventional methods such as "a method of reacting the polymer with (A) after being allowed to react", it is said that the prevention of viscosity increase, the appearance of the resin, the suppression of by-products, the transparency of the cured product, the heat resistance, etc. are significantly improved. It works.

Specifically, the urethane (meth) acrylate produced by the "method of collectively mixing and reacting (A), (B), and (C)" has a high viscosity, which makes stirring difficult. In addition, since the urethanization reaction proceeds non-uniformly, not only is there a high possibility of partial gelation, but urethane (meth) acrylate (by-product) that does not contain the polyol (A) in the skeleton is generated, and the transmittance Causes a decrease in flexibility and flexibility. In addition, since various urethane (meth) acrylates are produced, it becomes difficult to control the quality when used as an active energy ray-curable composition.

Further, when the reaction is carried out by the "method of reacting the polymer with (A) after reacting (B) and (C)", all the isocyanate groups of the polyisocyanate (B) are (meth) acrylate (C). Urethane (meth) acrylate (by-product) is produced by reacting with the hydroxyl group of. Since this by-product does not contain a polyol (A) skeleton, it not only exhibits crystallinity and a decrease in transmittance at 400 nm, but also has a high possibility of gelation.

Examples of the method for forming the urethane prepolymer of the present invention include the following methods 1 to 3.
[Method 1] A method in which a polyol (A) and a polyisocyanate (B) are mixed and reacted at once.
[Method 2] A method of reacting while dropping a polyol (A) into a polyisocyanate (B).
[Method 3] A method of reacting while dropping a polyisocyanate (B) into a polyol (A).

In the case of [Method 1], the polyol (A) and the polyisocyanate (B) are charged into the reactor and stirred until uniform. Then, it is desirable to start urethanization by adding a urethanization catalyst after raising the temperature as needed while stirring. The temperature may be raised as needed after the urethanization catalyst is added.

In [Method 1], (meth) acrylate (Y) may be used as a compatibilizer. In this case, the polyol (A) is charged into the reactor together with the (meth) acrylate (Y), stirred until uniform, and then the polyisocyanate (B) is charged to make it uniform. As a result, the viscosity of the reaction solution can be further reduced. Then, it is desirable to start urethanization by adding a urethanization catalyst after raising the temperature as needed while stirring. The temperature may be raised as needed after the urethanization catalyst is added.

If the urethanization catalyst is added before the polyol (A) and the polyisocyanate (B) are uniformly agitated, the urethanization reaction proceeds non-uniformly, causing problems such as gelation of the obtained urethane prepolymer. Tends to occur. Further, the reaction may be terminated with the unreacted polyisocyanate (B) remaining in the system. In this case, the by-product obtained by reacting the (meth) acrylate (C) to be reacted later with the remaining polyisocyanate (B) reduces the transmittance at 400 nm, which is not preferable.

The content of such by-products is preferably less than 7% by weight based on the target urethane prepolymer. When it is 7% by weight or more, the transmittance at 400 nm is remarkably lowered.

[Method 1] is industrially superior in that the highly viscous polyol (A) can be charged into the reactor as it is and that the urethane prepolymer can be produced in one pot. Further, since urethanization is started from a state in which the polyol (A) and the polyisocyanate (B) are uniformly mixed, it is excellent in that the reaction proceeds according to the stoichiometry. Further, it is effective in that a uniform urethane prepolymer can be obtained (for example, a urethane prepolymer having a narrow molecular weight distribution can be obtained) and that the production reproducibility is high. On the other hand, in the method of dropping either the polyol (A) or the polyisocyanate (B) to urethaneize as in [Method 2] and [Method 3] described later, the reaction species in the system are affected by the dropping time. Since the ratios are different, it is disadvantageous that a uniform urethane prepolymer cannot be obtained, that is, the molecular weight distribution of the obtained urethane prepolymer becomes wide.

In the case of [Method 2], a polyisocyanate (B) and a urethanization catalyst are charged in a reactor, stirred until uniform, the temperature is raised as necessary, and the polyol (A) is dropped and reacted. And.

In [Method 2], (meth) acrylate (Y) may be used as a compatibilizer. Specifically, polyisocyanate (B), urethanization catalyst, and (meth) acrylate (Y) are charged and stirred until uniform. Then, the temperature is raised as necessary, and the reaction is carried out while dropping the polyol (A) or the uniform mixed solution of the polyol (A) and the (meth) acrylate (Y).

In the case of [Method 3], the reactor is charged with the polyol (A) and the urethanization catalyst, stirred until uniform, the temperature is raised as necessary, and the polyisocyanate (B) is dropped and reacted. And.

In [Method 3], (meth) acrylate (Y) may be used as a compatibilizer. Specifically, the polyol (A), the urethanization catalyst, and the (meth) acrylate (Y) are charged and stirred until uniform. After that, the temperature is raised as necessary, and a uniform mixed solution of polyisocyanate (B) or polyisocyanate (B) and (meth) acrylate (Y) is dropped and reacted.

In the case of [Method 3], since the polyisocyanate (B) is dropped into a large amount of the polyol (A) and reacted, the isocyanate group of the polyisocyanate (B) is urinated with the hydroxyl group of the polyol (A). When the polyol (A) is a diol and the polyisocyanate (B) is a diisocyanate, a diol having hydroxyl groups at both ends of the ABA type is formed as a by-product, and 2 mol of the diol is added to this. Polyisocyanate (B) (diisocyanate) reacts, and when written schematically, a compound having an isocyanate group at both ends of the BAB-AB type is by-produced, and the same reaction is repeated. If written specifically, a large amount of compounds having the following structure may be produced as a by-product.
B- [ _{AB] n-} AB (integer of n = 1 or more)

When a large amount of such by-products are produced as a by-product, the urethane (meth) acrylate obtained by reacting the (meth) acrylate (C) has a low acrylic density, so that the cured product cannot obtain a sufficient cross-linking density. The hardness will decrease.

Although the by-products described in [Method 3] may be produced in [Method 2], the amount tends to be small. Further, in the case of [Method 2], the viscosity of the obtained urethane prepolymer tends to be low.

Therefore, in order to obtain the desired urethane prepolymer in good yield, [Method 1] and [Method 2] are preferably used, and [Method 1] is particularly preferably used.

In any of the methods, when the urethane prepolymer is formed by the reaction with the polyol (A) and the polyisocyanate (B), it is preferable to carry out the reaction until all the hydroxyl groups in the reaction solution are urethaneized.

At the end point of the reaction, the isocyanate group concentration in the reaction solution was measured, and all the hydroxyl groups charged in the system were below the isocyanate group concentration when urethanized, and the isocyanate group concentration did not change. Can be confirmed by.

From the above viewpoint, the molar ratio of the hydroxyl group of the polyol (A) to the isocyanate group of the polyisocyanate (B) is not particularly limited, but for example, 1.1 to 2.0 mol of the isocyanate group is preferable with respect to 1 mol of the hydroxyl group. Can be used in 1.1 to 1.4 mol.

When the target urethane (meth) acrylate (X) is produced by reacting the urethane prepolymer with the (meth) acrylate (C), if a large amount of unreacted isocyanate groups remain, gelation may occur or gelation may occur. Problems such as poor curing of the coating film may occur. In order to avoid these problems, alcohol (D) may be used in addition to (meth) acrylate (C) in the reaction.

Further, in order to avoid these problems, in the above reaction, the reaction is carried out so that the number of moles of the hydroxyl group of the (meth) acrylate (C) becomes excessive with respect to the number of moles of the isocyanate group of the urethane prepolymer, and the reaction solution. It is necessary to continue the reaction until the residual isocyanate group concentration in the mixture reaches 0.05% by weight or less. In the above reaction, the number of moles of the hydroxyl group of the (meth) acrylate (C) was 1.0 to 1.1 mol, preferably 1.0 to 1 mol, with respect to 1 mol of the isocyanate group of the urethane prepolymer. It can be 1.05 mol. When the alcohol (D) is used, it is preferable that the total amount of moles of the hydroxyl groups of the (meth) acrylate (C) and the alcohol (D) is included in the above range.

In the method for producing urethane (meth) acrylate (X), it is preferable to carry out the process in the presence of a polymerization inhibitor such as dibutylhydroxytoluene, hydroquinone, hydroquinone monomethyl ether and phenothiazine for the purpose of preventing polymerization. The amount of these polymerization inhibitors added is preferably 1 to 10000 ppm (weight basis), more preferably 100 to 1000 ppm, still more preferably 400 to 1000 ppm, based on the urethane (meth) acrylate (X) to be produced. If the amount of the polymerization inhibitor added is less than 1 ppm with respect to urethane (meth) acrylate (X), a sufficient polymerization inhibitory effect may not be obtained, and if it exceeds 10,000 ppm, the physical properties of the product may be adversely affected. There is.

In the method for producing urethane (meth) acrylate (X) of the present invention, it is preferable to carry out the process in a molecular oxygen-containing gas atmosphere. The oxygen concentration is appropriately selected in consideration of safety.

In the method for producing urethane (meth) acrylate (X) of the present invention, a catalyst (urethanization catalyst) may be used in order to obtain a sufficient reaction rate. As the catalyst, dibutyltin dilaurate, tin octylate, tin chloride and the like can be used, but dibutyltin dilaurate is preferable from the viewpoint of reaction rate. The amount of these catalysts added is usually 1 to 3000 ppm (weight basis), preferably 50 to 1000 ppm, based on the urethane (meth) acrylate (X) produced. If the amount of the catalyst added is less than 1 ppm, a sufficient reaction rate may not be obtained, and if it is added more than 3000 ppm, various physical properties of the product may be adversely affected, such as a decrease in light resistance.

The urethane (meth) acrylate (X) of the present invention can be produced in the presence of a known volatile organic solvent. The volatile organic solvent can be distilled off under reduced pressure after the urethane (meth) acrylate (X) is produced. Further, the volatile organic solvent remaining in the active energy ray-curable composition can be applied to the transparent substrate and then removed by reducing the pressure (drying). The volatile organic solvent means an organic solvent having a boiling point not exceeding 200 ° C.

However, from the production of urethane (meth) acrylate (X) to the formulation of the active energy ray-curable composition, it is possible to prepare the active energy ray-curable composition without using any volatile organic solvent in a sealed state. It is preferable in the curing system in. That is, it is preferable that the active energy ray-curable composition of the present invention does not contain a volatile organic solvent. Here, "not included" means that the proportion of the active energy ray-curable composition in the whole is 1% by weight or less, preferably 0.5% by weight or less, and 0.1% by weight. More preferably, it is less than%.

In the method for producing urethane (meth) acrylate (X) of the present invention, the reaction is preferably carried out at a temperature of 130 ° C. or lower, more preferably 40 to 130 ° C. If it is lower than 40 ° C., a practically sufficient reaction rate may not be obtained, and if it is higher than 130 ° C., the double bond portion may be crosslinked by radical polymerization by heat to form a gelled product.

When forming the urethane prepolymer of the present invention, the reaction is carried out until the isocyanate group concentration in the reaction solution becomes equal to or less than the isocyanate group concentration remaining when all the hydroxyl groups subjected to the reaction are urethanized. It is preferable to form. The residual isocyanate group concentration can be analyzed by gas chromatography, titration method or the like.

The isocyanate group concentration in the reaction solution for producing urethane (meth) acrylate (X) from the urethane prepolymer is usually adjusted to 0.1% by weight or less of residual isocyanate groups. The residual isocyanate group concentration is analyzed by gas chromatography, titration method or the like.

In addition, in order to adjust the concentration of the (meth) acryloyl group of urethane (meth) acrylate (X), a part of the terminal (meth) acryloyl group may be modified with an alkoxy group. By modifying to an alkoxy group, for example, the wettability with a base material can be adjusted.

The above-mentioned "(meth) acryloyl group concentration" can be calculated by applying the following formula.

[Calculation formula for (meth) acryloyl group concentration]
"(Meta) acryloyl group concentration (mol / kg)" = "weight (g) of (meth) acrylate (C)" x "number of (meth) acryloyl groups in (meth) acrylate (C) molecule" ÷ "(meth) ) Molecular weight of acrylate (C) ”× 1000 ÷“ Weight (g) of urethane (meth) acrylate (X) produced ”

The "(meth) acryloyl group number" of the (meth) acrylate (C) is, for example, the (meth) acryloyl group number is "1" for 2-hydroxyethyl acrylate, and the (meth) acryloyl group number is "1" for pentaerythritol triacrylate. 3 ”.

In the present invention, the concentration of the (meth) acryloyl group of urethane (meth) acrylate (X) is not particularly limited, but is preferably 0.05 to 0.80 mol / kg, more preferably 0.10 to 0.70 mol. / Kg, more preferably 0.15 to 0.60 mol / kg.

If the (meth) acryloyl group concentration is less than 0.05 mol / kg, curing may be insufficient even when irradiated with active energy rays, and the initial adhesion to the substrate is reduced due to a decrease in cohesive force. It is not preferable because it does. Further, if the (meth) acryloyl group concentration exceeds 0.80 mol / kg, the heat resistance of the cured product is lowered, which is not preferable. Specifically, when the cured product is tested under the conditions of 95 ° C. and 1000 hours, the decrease in heat resistance causes an increase in the hardness of the coating film, a decrease in adhesion to the substrate, and a curing shrinkage. , It is a defect that the shape of the coating film changes.

[Monofunctional (meth) acrylate (Y)]
Since the active energy ray-curable composition of the present invention contains a monofunctional (meth) acrylate (Y), it is possible to accurately adjust the viscosity and the Tg of the cured coating film in producing urethane (meth) acrylate. It has the effects of preventing viscosity increase, resin appearance, suppression of by-products, transparency of cured product, heat resistance, and the like. The monofunctional (meth) acrylate refers to a (meth) acrylate having one acryloyl group in the molecule.

As described above, (meth) acrylate (Y) may be used as a compatibilizer when forming the urethane prepolymer. By using (meth) acrylate (Y) as a compatibilizer, raw materials (for example, polyol (A) and polyisocyanate (B)) can be compatible with each other. Further, when the urethane prepolymer is formed, the viscosity of the reaction solution may increase, and at that time, it also acts as a so-called diluent that alleviates the increase in viscosity. Further, by using it when forming the urethane prepolymer, it is possible to omit the work of adding the (meth) acrylate (Y) to the urethane prepolymer again, so that the work efficiency is improved.

The amount of the (meth) acrylate (Y) used is not particularly limited, but is, for example, 5 to 60 with respect to the total amount (100% by weight) of the urethane (meth) acrylate (X) and the (meth) acrylate (Y). It is% by weight, preferably 10 to 50% by weight. If it is less than 5% by weight, the viscosity of the obtained urethane (meth) acrylate becomes high, it becomes difficult to handle, and gelation may occur. On the other hand, if it exceeds 60% by weight, when applied, the viscosity is too low and the wettability with the transparent substrate deteriorates, which may reduce the flexibility and heat resistance of the urethane (meth) acrylate.

The monofunctional (meth) acrylate is not particularly limited, but a monofunctional (meth) acrylate that is not a polyether acrylate (PO-modified product, EO-modified product, etc.) is preferable from the viewpoint of heat resistance. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, glycerin mono (meth) acrylate, glycidyl (meth) acrylate, dicyclopentenyl (meth) acrylate, n-butyl (meth) acrylate, β-carboxyethyl ( Meta) acrylate, isobornyl (meth) acrylate, octyl / decyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, isodecyl (meth) acrylate, n-lauryl (meth) acrylate, n-stearyl (meth) acrylate, cyclylhexyl (meth) acrylate, other alkyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxy Examples thereof include butyl (meth) acrylate, but n-octyl (meth) acrylate, isobornyl (meth) acrylate, and octyl / decyl (meth) acrylate are preferable, and n-octyl (meth) acrylate is particularly preferable. Two or more types of monofunctional (meth) acrylate may be used in combination depending on the purpose.

As the above monofunctional (meth) acrylate, a commercially available product may be used. For example, the product name "β-CEA" (manufactured by Daicel Ornex Co., Ltd., β-carboxyethyl acrylate) and the product name "IBOA" (Dicel Ornex) may be used. ODA-N (manufactured by Daicel Ornex, octyl / decyl acrylate), product name "NOA" (manufactured by Osaka Organic Chemical Co., Ltd., normal octyl acrylate), etc. are available from the market. It is possible.

[Photopolymerization Initiator (Z)]
The photopolymerization initiator (Z) of the present invention varies depending on the type of active energy ray and the type of urethane (meth) acrylate (X), and is not particularly limited, but is not particularly limited, but is a known photoradical polymerization initiator or photocationic polymerization initiator. Agents can be used, such as 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-. 2-Methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropane-1-one, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) Ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzyl dimethyl ketal , Benzophenone, benzoyl benzoic acid, methyl benzoyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylicized benzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3'-dimethyl-4-methoxybenzophenone, thioxanthone, 2 -Chlorthioxanson, 2-methylthioxanson, 2,4-dimethylthioxanson, isopropylthioxanson, 2,4-dichlorothioxanson, 2,4-diethylthioxanson, 2,4-diisopropylthio Examples thereof include xanson, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, methylphenylglioxylate, benzyl, camphorquinone and the like. Two or more photopolymerization initiators may be used in combination depending on the purpose.

The amount of the photopolymerization initiator used is not particularly limited, but is preferably 1 to 20 parts by weight, more preferably 1 to 5 parts by weight, based on 100 parts by weight of the total amount of the resin content of the active energy ray-curable composition. It is a department. If the amount of the photopolymerization initiator used is less than 1 part by weight, curing failure may occur. Conversely, if the amount of the photopolymerization initiator used is large, the odor derived from the photopolymerization initiator remains from the cured coating film. I have something to do. The "resin component" means a curable resin contained in the active energy ray-curable composition, for example, urethane (meth) acrylate (X), monofunctional (meth) acrylate (Y), and bifunctional. Refers to the above (meth) acrylate and the like. The photopolymerization initiator (Z) and the solvent do not correspond to the resin component.

Various additives can be further added to the active energy ray-curable composition of the present invention, if necessary. Examples of such additives include fillers, dyes and pigments, leveling agents, ultraviolet absorbers, light stabilizers, defoamers, dispersants, thixotropy-imparting agents and the like. The blending amount of these additives is not particularly limited, but is preferably 0 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, based on 100 parts by weight of the total amount of the resin content of the active energy ray-curable composition. It is a part by weight.

Since the active energy ray-curable composition of the present invention has high compatibility with other components that can be contained in the composition such as bifunctional or higher functional (meth) acrylate, its viscosity can be easily adjusted. In addition, the desired properties (for example, hardness, deformation resistance, flexibility) can be easily imparted to the cured product.

[Bifunctional or higher (meth) acrylate]
The bifunctional or higher functional (meth) acrylate is not particularly limited, but has 2 (meth) acryloyl groups in molecules such as 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, and tricyclodecanedimethanol diacrylate. Examples thereof include compounds having the above. The active energy ray-curable composition of the present invention may contain the above-mentioned bifunctional or higher (meth) acrylate, and the content thereof is not particularly limited, but the total amount (100% by weight) of the active energy ray-curable composition. ), More preferably 0.1 to 90% by weight, more preferably 1 to 80% by weight, still more preferably 5 to 60% by weight. The content of bifunctional or higher (meth) acrylate with respect to urethane (meth) acrylate (X) (100 parts by weight) is preferably 0.1 to 400 parts by weight, more preferably 1 to 300 parts by weight, still more preferably. Is 3 to 200 parts by weight, most preferably 5 to 150 parts by weight.

<Laminated body>
The laminate of the present invention has a cured product layer of the active energy ray-curable composition between a first transparent base material selected from glass and plastic and a second transparent base material selected from glass and plastic. It is not particularly limited as long as it is a laminated body having. Preferably, the active energy ray-curable composition is applied onto the first transparent substrate to form a resin layer, the second transparent substrate is adhered onto the resin layer, and then the transparent group is formed. By irradiating the material with active energy rays such as ultraviolet rays or electron beams, the active energy ray-curable composition is cured in an extremely short time to form a cured product layer to obtain a laminate. Can be done. FIG. 1 shows one aspect of the laminated body.

[Transparent substrate]
As the transparent base material, a plastic base material such as a transparent plastic film can be used in addition to a glass base material such as a transparent glass plate.

As the plastic base material, an existing transparent material can be used and is not particularly limited, but for example, a polyolefin resin such as polyethylene, an ethylene-propylene copolymer, an ethylene-vinyl acetate copolymer, polyethylene terephthalate, and the like. Examples thereof include polyester resins such as polyethylene naphthalate and polybutylene terephthalate, acrylic resins, and polycarbonate resins. Of these, a polycarbonate resin and an acrylic resin are particularly preferably used.

[Application / injection / curing method to transparent substrate]
When the active energy ray-curable composition of the present invention is applied to a transparent substrate (for example, a glass substrate such as a glass plate or a plastic substrate such as a plastic film), the coating method is not particularly limited and is sprayed. It is possible to use a method, an airless spray method, an air spray method, a roll coating method, a bar coating method, a gravure method, or the like. Among them, the roll coating method is most preferably used from the viewpoint of aesthetics, cost, workability and the like. The coating may be carried out by a so-called in-line coating method in which the plastic film or the like is manufactured in the manufacturing process, or by a so-called offline coating method in which the transparent substrate already manufactured is coated in a separate process. An offline coat is preferable from the viewpoint of production efficiency. Further, when injecting, it is preferable to use a cartridge in order to prevent the generation of air bubbles.

The thickness of the cured product layer in the laminate of the present invention is preferably 30 to 300 μm, more preferably 50 to 200 μm. When the layer thickness exceeds 300 μm, the amount of the resin composition to be applied becomes large, which may increase the cost or reduce the uniformity of the film thickness. Further, if it is less than 30 μm, the softness property of the curable resin cannot be exhibited.

The light source for irradiating ultraviolet rays is not particularly limited, and for example, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, or the like is used. The irradiation time varies depending on the type of light source, the distance between the light source and the coated surface, and other conditions, but is several tens of seconds at the longest, and is usually several seconds. Usually, an irradiation source having a lamp output of about 80 to 300 W / cm is used. In the case of electron beam irradiation, it is preferable to use an electron beam having an energy in the range of 50 to 1000 KeV and to set the irradiation amount to 2 to 5 Mrad. After irradiation with active energy rays, heating may be performed as necessary to promote curing.

<Use of active energy ray-curable composition>
The active energy ray-curable composition of the present invention can be used as an interlayer filler (curable composition for interlayer filling) as described above, but other compositions for adhesives and compositions for coating agents, particularly optical members Alternatively, it can be used as a pressure-sensitive adhesive composition or a coating agent composition used for an optical film.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples.

<Measurement method, test method, evaluation method of physical properties>
The measurement method, test method, and evaluation method of physical properties are shown below.
[Measurement of weight average molecular weight]
The weight average molecular weight of urethane (meth) acrylate or the like was determined by the GPC (gel permeation gas chromatography) method under the following measurement conditions based on standard polystyrene. For the weight average molecular weight of urethane (meth) acrylate in Table 1, two significant figures are shown.
Equipment used: TOSO HLC-8220GPC
Pump: DP-8020
Detector: RI-8020
Column type: Super HZM-M, Super HZ4000, Super HZ3000, Super HZ2000
Solvent: Tetrahydrofuran phase Flow rate: 1 mL / min Column pressure: 5.0 MPa
Column temperature: 40 ° C
Sample injection volume: 10 μL
Sample concentration: 0.2 mg / mL

[Appearance test of resin composition before curing (resin appearance)]
The appearance of the resin composition before curing was confirmed. The resin composition was stored at −30 ° C. (-30 ° C.) for 1 hour, and the presence or absence of white turbidity and coloring due to crystallization and the like was visually evaluated according to the following criteria.

Specifically, when neither cloudiness nor coloring can be visually recognized, the result is considered to be good (clear), and "○" is described in the "resin appearance" column of Table 2. On the other hand, when either cloudiness or coloring was visually recognized, the result was considered to be defective (impaired appearance), and "x" was described in the "resin appearance" column of Table 2.

[Compatibility test with bifunctional monomer]
Add 1,6-hexanediol diacrylate (manufactured by Daicel Ornex Co., Ltd., product name HDDA) to the resin composition before curing so that it has the same weight ratio as the urethane (meth) acrylate-containing material contained in the resin composition. In addition, a test solution was obtained. Further, the same operation was carried out except that the 1,6-hexanediol diacrylate was replaced with tricyclodecanedimethanol diacrylate (manufactured by Daicel Ornex Co., Ltd., product name IRR214K) to obtain a test solution.

White turbidity and separation were visually confirmed for both test solutions. When neither cloudiness nor separation could be confirmed, the result was considered to be good (clear), and "○" was entered in the "Compatibility" column of Table 2. If either one or both monomer solutions are visually confirmed to be cloudy or separated, the result is considered to be defective (poor appearance), and an "x" is displayed in the "Compatibility" column of Table 2. Was described.

[Evaluation of transparency of cured product]
As shown in FIG. 2, a square frame is made of silicon rubber on a microglass (dimensions: 1.0 x 76 x 26 mm) (inner dimensions: 1.0 x 40 x 10 mm), and inside the frame. 1.0 g of the active energy ray-curable composition was added dropwise. It was heated at 70 ° C., and when the surface became smooth, it was irradiated with ultraviolet rays under the following conditions.

(Ultraviolet irradiation conditions)
Irradiation intensity: 120 W / cm
Irradiation distance: 10 cm
Conveyor speed: 5 m / min Number of irradiations: 2 times

Using a spectrophotometer (product name UV-VISIBLE SPECTROPHOTO METER, manufactured by Shimadzu Corporation), the transmittance was measured using only microglass as a reference, and evaluated according to the following criteria.

When the transmittance at 400 nm was 95% or more, the transmittance was considered to be good, and “◯” was entered in the “Transparency” column of Table 2. On the other hand, when the transmittance at 400 nm is less than 95%, the transmittance is considered to be poor, and “x” is described in the “Transparency” column of Table 2.

[Evaluation of heat resistance of cured product]
The glass laminate (test piece A) shown in FIG. 3 was stored under the following heat-resistant conditions, and changes in APHA (hue) and shape of the test piece A were observed. Note that FIG. 3A is a view of the glass laminate viewed from above, and FIG. 3B is a view of the glass laminate viewed from the side.

(Preparation of test piece A)
The glass laminate (test piece A) shown in FIG. 3 was prepared as follows. First, 0.5 g (± 0.01 g) of the active energy ray-curable composition was accurately weighed and placed on the center of a glass plate (thickness 1 mm, 5 cm square). Further, a glass plate having the same shape was covered over the glass plate, and the resin layer was spread in a circular shape (diameter 4 cm) to obtain a glass laminate. Then, ultraviolet irradiation was performed from one glass surface of the glass laminate using a high-pressure mercury lamp (manufactured by Eye Graphics) under the following conditions, and the glass laminate having a cured resin composition layer (test piece A). Got

(Ultraviolet irradiation conditions)
Irradiation intensity: 120 W / cm
Irradiation distance: 10 cm
Conveyor speed: 5 m / min Number of irradiations: 8 times (4 times each on both sides)

(Storage under heat resistant conditions)
Using a small environmental tester (product name SH-641, manufactured by ESPEC), the test plate (glass laminate, after curing) was stored under the condition of a temperature of 95 ° C. for 1000 hours.

(Measurement of APHA)
APHA is measured by using a spectrocolor meter (product name Spectro Color Meter SE2000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) to measure APHA of the glass laminate before and after storage under heat-resistant conditions, and evaluate it according to the following criteria. did.

If the increase in APHA before and after storage under heat-resistant conditions is 15 or more and less than 50, it is considered that the heat resistance is good from the viewpoint of hue, and "○" is displayed in the "hue change" column of "heat resistance" in Table 2. Described. On the other hand, if the increase in APHA before and after storage under heat-resistant conditions is 50 or more, it is considered that the heat resistance is poor from the viewpoint of hue, and "x" is added to the "hue change" column of "heat resistance" in Table 2. Described.

[Evaluation of heat resistance of cured product (shape change)]
The presence or absence of shape change of the test piece A after storage under heat-resistant conditions was visually measured and evaluated according to the following criteria.

Specifically, if the shape change (some shape change such as warpage, wrinkles, or misalignment of the pattern plate) cannot be visually recognized, the result is considered to be good, and "heat resistance" in Table 2 shows "heat resistance". "○" is described in the "Shape change" column. On the other hand, when the shape change was visually recognized, the result was considered to be defective, and "x" was entered in the "shape change" column of "heat resistance" in Table 2.

[Evaluation of heat resistance of cured product (change in coating film hardness)]
A square frame is made of silicon rubber on a glass (dimensions: 2 x 100 x 200 mm) plate (inner dimensions: 7 x 40 x 40 mm), and the active energy ray curable that has been preheated in the frame. The composition was added slowly so as not to generate bubbles as much as possible. When the bubbles were conspicuous, they were removed by putting them in an oven at 80 ° C. Then, it was heated at 80 ° C., and when the surface became smooth, it was irradiated with ultraviolet rays under the following conditions, and the coating film was turned inside out and irradiated with ultraviolet rays under the same conditions to obtain a test piece B.

(Ultraviolet irradiation conditions)
Irradiation intensity: 120 W / cm
Irradiation distance: 10 cm
Conveyor speed: 3.5 m / min Number of irradiations: 5 times

The A hardness of the test piece B was measured using an automatic constant pressure loader (GS-610, manufactured by Teclock Co., Ltd.) in accordance with JIS K 6253. The load at the time of measurement was 500 g, and the load drop speed was 9 mm / s. Then, the test piece B was stored at a temperature of 95 ° C. for 1000 hours. If the hardness value is less than ± 20% before and after storage, "○" is shown in the "Hardness change" column of "Heat resistance" in Table 2. On the other hand, if the value of the coating film hardness is ± 20% or more, “x” is described in the “hardness change” column of “heat resistance” in Table 2. The above-mentioned "hardness value" was calculated by dividing the hardness of the test piece B after storage by the hardness of the test piece B before storage.

<Synthesis example>
Examples and examples of synthesis of urethane (meth) acrylate (X) will be described below.

[Measurement of isocyanate group concentration]
The isocyanate group concentration was measured as follows. The measurement was carried out in a 100 mL glass flask under stirring with a stirrer.

(Measurement of blank value)
To 15 mL of THF, 15 mL of a THF solution of dibutylamine (0.1N) was added, and 3 drops of bromophenol blue (1% methanol diluted solution) were added to color the product blue, and then the normality was 0.1N. It was titrated with an aqueous solution of HCl. The titration amount of the aqueous HCl solution at the time of discoloration was defined as V _b (mL).

(Measurement of measured isocyanate group concentration)
The sample was _{weighed in W s} (g), dissolved in 15 mL of THF, and 15 mL of a THF solution of dibutylamine (0.1N) was added. After confirming that the solution was formed, 3 drops of bromophenol blue (1% methanol diluted solution) was added to color the mixture blue, and then the mixture was titrated with an aqueous HCl solution having a normal concentration of 0.1 N. The titration amount of the aqueous HCl solution at the time of discoloration was defined as V _s (mL).
The isocyanate group concentration in the sample was calculated by the following formula.
Isocyanate group concentration (% by weight) = (V _{b −} V _s ) × 1.005 × 0.42 ÷ W _s

Hereinafter, (A) to (D), (Y), and (Z) used in the synthesis example and the comparative synthesis example will be described.

[Polyprethane (A)]
"Pripol 2033" (compound name hydrogenated dimerdiol, hydroxyl value 210 mgKOH / g, weight average molecular weight 534); product name "Pripol 2033-LQ- (GD)" (manufactured by Crowder Japan)
"TMP" (compound name trimethylolpropane (TMP)); product name "TMP" (manufactured by Mitsubishi Gas Chemical Company)
"Preplast 3199" (compound name hydrogenated polyol (polyester polyol), hydroxyl value 55 mgKOH / g, weight average molecular weight 1934.5); product name "Priplast 3199-LQ- (GD)" (manufactured by Crowder Japan)
"Preplast 3197" (compound name hydrogenated polyol (polyester polyol), hydroxyl value 58 mgKOH / g, weight average molecular weight 2040); product name "Priplast 3197-LQ- (GD)" (manufactured by Crowder Japan)
"PT-2001" (compound name polypropylene glycol, hydroxyl value 57.1 mgKOH / g, weight average molecular weight 1964); product name "Sanniks PT-2001" (manufactured by Sanyo Chemical Industries, Ltd.)
"P3000" (Compound name: Hydrogenated polybutadiene glycol, Hydroxyl value: 0.56 Phth meq / g (Pthalic anhydride equivalent), Non-volatile content: 99.98%, Weight average molecular weight: 3571); Product name: "KRASOL HLBH P3000" (Nippon Soda) Made by the company)
"PP400" (compound name polypropylene glycol, hydroxyl value 277 mgKOH / g, weight average molecular weight 404); product name "Sannicks PP400" (manufactured by Sanyo Chemical Industries, Ltd.)

[Polyisocyanate (B)]
"IPDI" (compound name isophorone diisocyanate); product name "VESTANAT IPDI" (manufactured by Evonik Industries)
"HDI" (compound name hexamethylene diisocyanate); product name "HDI" (manufactured by Nippon Polyurethane Industry Co., Ltd.)
"TMDI" (compound name 2,2,4-trimethylhexamethylene diisocyanate); product name "TMDI" (manufactured by Evonik Industries)

[(Meta) Acrylate (C)]
"HEA" (compound name 2-hydroxyethyl acrylate); product name "β-HEA 2-hydroxyethyl acrylate" (manufactured by Nippon Shokubai Co., Ltd.)

[Alcohol (D)]
"2-EH"; 2-ethylhexyl alcohol (manufactured by Sankyo Chemical Co., Ltd.)

[(Meta) Acrylate (Y)]
"NOA" (compound name: normal octyl acrylate); product name "NOAA" (manufactured by Osaka Organic Chemical Co., Ltd.)
"IBOA" (compound name: isobornyl acrylate); product name "IBOA" (manufactured by Daicel Ornex)

[Photopolymerization Initiator (Z)]
Irg184 (Compound name 1-hydroxycyclohexylphenyl ketone); Product name "Irg184" (manufactured by BASF Japan Ltd.)

Examples of synthesis and comparative synthesis are described below, but the concentration notations "ppm", "% by weight", and "% by weight" are urethane (theoretically) obtained unless otherwise specified. ) Concentration for the entire acrylate-containing material.

(Synthesis Example 1)
A separable flask equipped with a thermometer and a stirrer was filled with 1.1 g of TMP, 800 ppm of dibutylhydroxytoluene (BHT), and 128.6 g (30% by weight) of NOA. The internal temperature was adjusted to 70 ° C., and the mixture was stirred for 1 hour to homogenize the inside of the system, cooled to 50 ° C. again, and 95.9 g of IPDI was added. After homogenizing the system, 100 ppm dibutyltin dilaurate (DBTDL) was added. Then, 182 g of prepol 2033 was added dropwise over 2 hours to prepare a urethane prepolymer. At this time, the internal temperature was set to 70 ° C. and the mixture was aged for 1 hour.

The completion of the reaction means that the isocyanate group concentration in the reaction solution is less than or equal to the residual isocyanate group concentration (hereinafter referred to as "theoretical end point isocyanate group concentration") when all the hydroxyl groups subjected to the reaction are urinated. I confirmed that. In this example, after confirming that the isocyanate group concentration in the reaction solution was equal to or less than the theoretical end point isocyanate group concentration (1.73% by weight), the process proceeded to the next operation.

After confirming the isocyanate group concentration of the urethane prepolymer, 10.9 g of 2-EH and 100 ppm of DBTDL were added and aged for 1 hour. Then, 9.9 g of HEA was added and aged for 3 hours. After confirming that the isocyanate group concentration was less than 0.05%, the reaction was terminated to obtain a urethane (meth) acrylate-containing product (X-1).

The molar ratio of prepol 2033, TMP, IPDI, HEA, and 2-EH used in the above reaction was 4.0: 0.1: 5.15: 1.02: 1.0. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.28 mol / kg.

(Synthesis Example 2)
Except for the fact that the molar ratios of polyisocyanate (B) and (meth) acrylate (C) were changed without using TMP and 2-EH, and 20% by weight of NOA was used as (meth) acrylate (Y). Obtained a urethane (meth) acrylate-containing material (X-2) in the same manner as in Synthesis Example 1. The molar ratio of prepol 2033, IPDI, and HEA used in the above reaction was 4.0: 5.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.58 mol / kg.

(Synthesis Example 3)
A urethane (meth) acrylate-containing material (X-3) was obtained in the same manner as in Synthesis Example 2 except that 20% by weight of IBOA was used as the (meth) acrylate (Y). The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.58 mol / kg.

(Synthesis Example 4)
Urethane (meth) acrylate-containing material (X-4) in the same manner as in Synthesis Example 2 except that HDI was used as the polyisocyanate (B) and the molar ratios of the polyol (A) and the polyisocyanate (B) were changed. Got The molar ratio of prepol 2033, HDI, and HEA used in the above reaction was 5.0: 6.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.51 mol / kg.

(Synthesis Example 5)
Urethane (meth) acrylate-containing material (X-5) in the same manner as in Synthesis Example 2 except that TMDI was used as the polyisocyanate (B) and the molar ratios of the polyol (A) and the polyisocyanate (B) were changed. Got The molar ratio of prepol 2033, TMDI, and HEA used in the above reaction was 5.0: 6.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.48 mol / kg.

(Comparative Synthesis Example 1)
Instead of prepole 2033, preplast 3199 was used as the polyol (A), the molar ratios of the polyol (A) and the polyisocyanate (B) were changed, and 30% by weight of NOA was added as the (meth) acrylate (Y). A urethane (meth) acrylate-containing material (CX-1) was obtained in the same manner as in Synthesis Example 2 except that it was used. The molar ratio of preplast 3199, IPDI, and HEA used in the above reaction was 6.0: 7.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.14 mol / kg.

(Comparative Synthesis Example 2)
Urethane (meth) was obtained in the same manner as in Comparative Synthesis Example 1 except that the molar ratios of the polyol (A) and the polyisocyanate (B) were changed and 20% by weight of NOA was used as the (meth) acrylate (Y). ) An acrylate-containing material (CX-2) was obtained. The molar ratio of preplast 3199, IPDI, and HEA used in the above reaction was 3.0: 4.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.27 mol / kg.

(Comparative Synthesis Example 3)
Comparison except that preplast 3197 was used as the polyol (A), the molar ratios of the polyol (A) and the polyisocyanate (B) were changed, and 20% by weight of NOA was used as the (meth) acrylate (Y). A urethane (meth) acrylate-containing material (CX-3) was obtained in the same manner as in Synthesis Example 1. The molar ratio of preplast 3197, IPDI, and HEA was 3.0: 4.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.29 mol / kg.

(Comparative Synthesis Example 4)
Except that PT-2001 was used as the polyol (A), the molar ratios of the polyol (A) and the polyisocyanate (B) were changed, and 20% by weight of NOA was used as the (meth) acrylate (Y). A urethane (meth) acrylate-containing material (CX-4) was obtained in the same manner as in Comparative Synthesis Example 1. The molar ratio of Sanniks PT-2001, IPDI, and HEA was 4.0: 5.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.22 mol / kg.

(Comparative Synthesis Example 5)
Using TMP and P3000 as the polyol (A) and 2-EH as the alcohol (D), the molar ratios of the polyol (A), polyisocyanate (B) and (meth) acrylate (C) were changed, and further (meth). A urethane (meth) acrylate-containing material (CX-5) was obtained in the same manner as in Comparative Synthesis Example 1 except that 20% by weight of NOA was used as the acrylate (Y). The molar ratio of TMP, P3000, IPDI, HEA, and 2-EH was 0.3: 1.4: 2.85: 1.82: 0.2. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.31 mol / kg.

(Comparative Synthesis Example 6)
Comparative synthesis except that PP400 was used as the polyol (A), the molar ratios of the polyol (A) and the polyisocyanate (B) were changed, and 20% by weight of NOA was used as the (meth) acrylate (Y). A urethane (meth) acrylate-containing material (CX-6) was obtained in the same manner as in Example 1. The molar ratio of PP400, IPDI, and HEA was 4.0: 5.0: 2.02. The (meth) acryloyl group concentration of urethane (meth) acrylate was 0.23 mol / kg.

Regarding the composition of the above urethane (meth) acrylate-containing substances (X-1) to (X-5), (CX-1) to (CX-6), and the concentration of the (meth) acryloyl group of the urethane (meth) acrylate. It is described in Table 1. The molar ratios of polyol (A), polyisocyanate (B), (meth) acrylate (C), and alcohol (D), which are constituents of urethane (meth) acrylate in the table, are shown. , (Meta) acrylate (Y) indicates the concentration (%) with respect to the entire urethane (meth) acrylate-containing material.

Urethane (meth) acrylate-containing substances (X-1) to (X-5), (CX-1) to (CX-6) contained in (A) to (D), (Y) and their contents, urethane Table 1 summarizes the (meth) acryloyl group concentration and weight average molecular weight of the (meth) acrylate.

(Preparation of active energy ray-curable composition)
Add 3 parts by weight of Irg184 as a photopolymerization initiator to each of 100 parts by weight of urethane (meth) acrylate-containing substances (X-1) to (X-5) and (CX-1) to (CX-6). The active energy ray-curable composition was obtained.

<Test result>
The obtained active energy ray-curable composition was subjected to each of the above tests and evaluations, and the results are shown in Table 2. In Table 2, the active energy ray-curable composition is simply referred to as "pre-curing composition".

As shown in Examples, it is clear that the active energy ray-curable composition containing the urethane (meth) acrylate (X) of the present invention has a good appearance of the resin before curing and good compatibility. Became. Furthermore, it has been clarified that the cured product has a performance that the hue change, the shape change, and the coating film hardness do not change even when exposed to high heat for a long time.

1 Cured material layer of active energy ray-curable composition 2 Transparent base material 3 Transparent base material 4 Silicon rubber 11 Resin 21 Microglass 31 Resin 41 Glass plate

Claims (4)

Urethane (meth) acrylate (X), which is a reaction product of urethane prepolymer having an isocyanate group and (meth) acrylate (C) having a hydroxyl group,
An active energy ray-curable composition containing a monofunctional (meth) acrylate (Y) and a photopolymerization initiator (Z).
The urethane prepolymer is a urethane prepolymer containing a polyol (A) and a polyisocyanate (B) as constituent components.
The polyol (A) is a polyol containing 50% by weight or more of hydrogenated dimerdiol having a weight average molecular weight of 200 to 1000.
The polyisocyanate (B) is Ri polyisocyanate der containing aliphatic diisocyanate 50 wt% or more,
An active energy ray-curable composition for interlayer filling, wherein the polyisocyanate (B) contains isophorone diisocyanate. The active energy ray-curable composition according to claim 1, further comprising a bifunctional or higher functional (meth) acrylate. The active energy ray-curable composition according to claim 1 or 2, wherein the monofunctional (meth) acrylate (Y) contains a normal octyl acrylate. The active energy ray-curable composition according to any one of claims 1 to 3, between a first transparent base material selected from glass and plastic and a second transparent base material selected from glass and plastic. Laminated body having a cured product layer of.

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