JP2018123207A - Active energy ray-curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable composition which comprises a urethane (meth)acrylate having high compatibility with a component which may be contained in a composition and whose cured product exhibits good oxidation resistance, transparency and heat resistance and to provide a laminate having a cured product layer of the active energy ray-curable composition.SOLUTION: There is provided an active energy ray-curable composition which comprises an urethane (meth)acrylate (X) which is a reaction product of a urethane prepolymer having an isocyanate group and a (meth)acrylate having a hydroxyl group, a monofunctional (meth)acrylate (Y) and a photopolymerization initiator (Z), wherein the urethane prepolymer contains a polyol (A) and a polyisocyanate (B) as constituents, the polyol (A) contains 50 wt.% or more of a hydrogenated dimer diol having a weight average molecular weight of 200 to 1000 and the polyisocyanate (B) contains 50 wt.% or more of an aliphatic diisocyanate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an active energy ray-curable composition that can be used as an interlayer filler for transparent substrates for displays such as personal computers, televisions, and mobile phones, and a cured layer of the active energy ray-curable composition. It relates to a laminate having the same.

  A display used for a personal computer, a car navigation system, a television, a mobile phone, or the like projects an image with light from a backlight. Various transparent substrates such as glass substrates such as glass plates and plastic substrates such as plastic films, including color filters, are used for displays, and the effects of light scattering and absorption of these transparent substrates are used. The amount of light output from the light source to the outside of the display is reduced. If this decrease width becomes large, the screen becomes dark and the visibility decreases. In order to improve the visibility, it is possible to increase the antireflection property of the display surface layer or increase the amount of light from the light source.

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

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

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

  In these prior documents, a urethane (meth) acrylate containing a hydrogenated material such as hydrogenated polyolefin polyol as a constituent component and a composition containing the same are reported. 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, the urethane (meth) acrylate has a tendency to deteriorate in compatibility with other components (for example, bifunctional or higher (meth) acrylate) that can be contained in the composition because of its high hydrophobicity. . Therefore, when using the urethane (meth) acrylate, it is difficult to adjust the viscosity of the composition and to impart desired properties (for example, hardness, deformation resistance, flexibility) to the cured product. there were.

  In addition, the urethane (meth) acrylates described in these prior documents have a drawback that they have a high viscosity and cannot be produced on a large scale. In addition, these urethane (meth) acrylates and compositions thereof become cloudy at low temperatures and have poor transparency, and low heat resistance of the cured product, that is, the cured product is yellowed at high temperatures. Or have a shape change. Therefore, it was insufficient as an interlayer filler for a display substrate.

  Moreover, the base material for smart phones and tablets is calculated | required, and the further reduction of hardening shrinkage is calculated | required as an interlayer filler. Furthermore, with the generalization of the use environment, further improvement in the heat resistance of the cured product and the adhesion to the transparent substrate is required.

  Accordingly, an object of the present invention is to have a high compatibility with components that can be contained in the composition, including a low-viscosity urethane (meth) acrylate, and the cured product has good oxidation resistance, transparency, and heat resistance. 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 intensive studies to achieve the above object, the present inventor has obtained a urethane (meth) acrylate, a monofunctional (meth) acrylate, which is a reaction product of a specific urethane prepolymer and a (meth) acrylate having a hydroxyl group, And an active energy ray-curable composition containing a photopolymerization initiator was found useful as a curable composition for interlayer filling of transparent substrates such as glass substrates and plastic substrates.

That is, the present invention is a urethane (meth) acrylate (X) that 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 comprising 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 dimer diol having a weight average molecular weight of 200 to 1,000,
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.

  Moreover, it is preferable that the said active energy ray curable composition contains bifunctional or more (meth) acrylate further.

  The active energy ray-curable composition is preferably for interlayer filling.

  In addition, in this invention, the hardened | cured material layer of the said active energy ray curable composition is provided between the 1st transparent base material chosen from glass and a plastics, and the 2nd transparent base material chosen from glass and a plastics. The laminated body which has is also demonstrated.

  The urethane (meth) acrylate (X) in the active energy ray-curable composition of the present invention does not increase in viscosity during its production, has few by-products, and can be contained in the composition. Highly compatible with components (for example, bifunctional or higher acrylic monomers). For this reason, the active energy ray-curable composition of the present invention does not deteriorate the appearance of the resin due to white turbidity at low temperatures, and the viscosity can be easily adjusted. In addition, the cured product of the present invention has good oxidation resistance, transparency, and heat resistance. Furthermore, since the compatibility is high as described above, it is possible to achieve the desired properties of the cured product (for example, hardness, deformation resistance, flexibility, etc.). Moreover, when the active energy ray curable composition of this invention is used as an interlayer filler, the adhesiveness retention of the hardened | cured material and a base material is favorable.

  In addition, the active energy ray-curable composition of the present invention is filled between the transparent base materials of a display used in a personal computer, a car navigation system, a TV, a mobile phone (smart phone, etc.), a tablet, etc. This is useful in that it can prevent light scattering at the interface, and can provide a laminate that hardly undergoes a hue change or shape change during a heat resistance test.

It is the schematic which shows the one aspect | mode of the laminated body of this invention. It is the schematic which shows the aspect of the glass laminated body used by the present Example. It is the schematic which shows the aspect of the glass laminated body used by the present Example. (A) in a figure is the figure which looked at the glass laminated body from the top, (B) is the figure which looked at the glass laminated body from the side.

<Active energy ray-curable composition>
The active energy ray-curable composition of the present invention is 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, and a monofunctional (meth). An active energy ray-curable composition containing an acrylate (Y) and a photopolymerization initiator (Z), wherein the urethane prepolymer includes a polyol (A) and a polyisocyanate (B) as constituent components. It is a prepolymer, the polyol (A) is a polyol containing 50% by weight or more of hydrogenated dimer diol having a weight average molecular weight of 200 to 1000, and the polyisocyanate (B) is 50 weights of aliphatic diisocyanate. % Polyisocyanate containing at least%.

  In addition, the urethane prepolymer containing the isocyanate group is “urethane prepolymer”, the polyol (A) is “(A)”, the polyisocyanate (B) is “(B)”, and The (meth) acrylate (C) having a hydroxyl group of “(meth) acrylate (C)” or “(C)” and the alcohol (D) having one hydroxyl group described later are referred to as “alcohol (D)” or “( D) ”, the above monofunctional (meth) acrylate (Y) as“ (meth) acrylate (Y) ”or“ (Y) ”, and the photopolymerization initiator (Z) described later 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 (meth) acrylate (C), and the urethane prepolymer comprises a polyol (A) and a polyisocyanate (as a constituent component). B), the polyol (A) is a polyol containing 50% by weight or more of hydrogenated dimer diol having a weight average molecular weight of 200 to 1000, and the polyisocyanate (B) contains 50 aliphatic diisocyanates. It is characterized by being a polyisocyanate containing at least wt%. The urethane (meth) acrylate (X) of the present invention may be a reaction product of a urethane prepolymer, (meth) acrylate (C), and alcohol (D).

  Although the weight average molecular weight (Mw) of urethane (meth) acrylate (X) is not specifically limited, For example, it is preferable that it is 8000-20000, More preferably, it is 10000-18000. When the weight average molecular weight is less than 8000, the flexibility is lowered and the resin appearance tends to deteriorate. On the other hand, when the weight average molecular weight exceeds 20000, the compatibility of the urethane (meth) acrylate obtained tends to deteriorate. The “weight average molecular weight” in the present invention is a value in terms of polystyrene as measured by GPC.

[Polyol (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 dimer diol having a weight average molecular weight of 200 to 1,000. Two or more polyols may be used in combination depending on the purpose.

  Although the weight average molecular weight (Mw) of hydrogenated dimer diol will not be specifically limited if it is the range of 200-1000, Preferably it is 300-800. When the weight average molecular weight is less than 200, Tg of urethane (meth) acrylate is increased, flexibility is lowered, resin appearance is deteriorated, and by-products tend to increase. On the other hand, when the weight average molecular weight exceeds 1000, the compatibility of the urethane (meth) acrylate obtained tends to deteriorate.

  The hydrogenated dimer diol is obtained by reducing at least one of dimer acid, hydrogenated dimer acid, and lower alcohol ester thereof in the presence of a catalyst so that the carboxylic acid or carboxylate part of the dimer acid is an alcohol, and carbon- In the case of having a carbon double bond, the main component is a diol obtained by hydrogenating the double bond. For example, the structure of the main component of the hydrogenated dimer diol can be represented by the following formulas (1) and (2).

In the formula, each of R ¹ and R ² is an alkyl group, 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.

  A commercially available product may be used as the hydrogenated dimer diol having a weight average molecular weight of 200 to 1000, and examples thereof include “Pripol 2033” and “Plipol 2030” manufactured by Claude Japan.

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

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

  Commercially available products may be used as polyols other than hydrogenated dimer diol having a weight average molecular weight of 200 to 1000, such as “Preplast 3197” and “Preplast 3199” manufactured by Croda Japan Co., Ltd., “Trimethylol” manufactured by Mitsubishi Gas Chemical Company, Inc. "Propane (TMP)", Sanyo Kasei's "Sanniks HD-402 (pentaerythritol modified with polypropylene glycol)", "Sanniks HD-250 (glycerin modified with polypropylene glycol)", Idemitsu Kosan "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 dimer diol having a weight average molecular weight of 200 to 1000 as a constituent component 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, it is preferably 60% by weight or more, more preferably 80% by weight, still more preferably 95% by weight, and particularly preferably 99% by weight or more.

[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 polyisocyanates may be used in combination depending on the purpose.

  Examples of the aliphatic diisocyanate include alicyclic diisocyanates, linear or branched aliphatic diisocyanates, and aliphatic diisocyanate compounds obtained by hydrogenating aromatic isocyanates. Although it does not restrict | limit especially as said alicyclic diisocyanate, For example, isophorone diisocyanate etc. are mentioned. Examples of the aliphatic diisocyanate include linear aliphatic diisocyanates such as hexamethylene diisocyanate; branched aliphatic diisocyanates such as 2,2,4-trimethylhexamethylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate. Is mentioned. Examples of the diisocyanate compound obtained by hydrogenating the aromatic isocyanate include hydrogenated xylylene diisocyanate and hydrogenated diphenylmethane diisocyanate.

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

  Examples of the polyisocyanate other than the aliphatic diisocyanate that can be contained in the polyisocyanate (B) include, for example, 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 component is not particularly limited as long as it is 50% by weight or more based on the total amount of the polyisocyanate (B), but is preferably 60% by weight or more, and 80% by weight. % Is more preferable, 95% by weight is further preferable, and 99% by weight or more is particularly preferable.

[(Meth) 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. For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxynormalpropyl (meth) acrylate, 4 -Having one (meth) acryloyl group such as hydroxybutyl (meth) acrylate, and further having two or more (meth) acryloyl groups such as (meth) acrylate having a hydroxyl group and pentaallythritol triacrylate. Furthermore, a (meth) acrylate having a hydroxyl group can be used. In addition, (meth) acrylate (C) may use 2 or more types together according to the objective.

  A commercially available product may be used as the (meth) acrylate (C), 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. For example, an aliphatic or alicyclic primary having a molecular weight in the range of 70 to 400 and having 3 or more carbon atoms. An alcohol is preferred. In addition, (meth) acrylate (C) is not included in alcohol (D). When the alcohol has less than 3 carbon atoms or a molecular weight of less than 70, it is not preferred 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 is lowered and the reaction time may be prolonged, which is not preferable. Moreover, the alcohol which has an aromatic ring is unpreferable since the hue of the urethane (meth) acrylate (X) obtained may become high, or a weather resistance may be inferior. In addition, you may use 2 or more types of said alcohol together according to the objective.

  Examples of the alcohol (D) include 1-butanol, 1-heptanol, 1-hexanol, normal octyl alcohol, 2-ethylhexyl alcohol, cyclohexane methanol, capryl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol (cetanol), and stearyl alcohol. And mixtures thereof. Of these, 2-ethylhexyl alcohol is preferable from the viewpoints of boiling point, price, and availability.

[Method for producing urethane (meth) acrylate (X)]
The urethane (meth) acrylate (X) of the present invention is obtained by forming a urethane prepolymer by subjecting the polyol (A) and the polyisocyanate (B) to a urethanization reaction, and then the urethane prepolymer and (meth) acrylate. It can be produced by reacting with (C). In addition, when making a urethane prepolymer and (meth) acrylate (C) react, you may use alcohol (D) simultaneously with (meth) acrylate (C). In addition, monofunctional (meth) acrylate (Y) may be used as a compatibilizing agent when a urethane prepolymer is formed (that is, during the 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 in which (A), (B), and (C) are mixed and reacted” or “(B) and (C) are reacted”. After the treatment, the viscosity increase prevention, resin appearance, suppression of by-products, transparency of the cured product, heat resistance and the like are remarkably improved as compared with the conventional method such as “method of reacting the polymer and (A)”. There is an effect.

  Specifically, since the urethane (meth) acrylate produced by the “method of mixing and reacting (A), (B), and (C) at once” has a high viscosity, stirring becomes 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 polyol (A) in the skeleton is generated, and the transmittance Cause lowering of flexibility and flexibility. Moreover, since various urethane (meth) acrylates are produced, quality control becomes difficult when used as an active energy ray-curable composition.

  Further, when the reaction is carried out by “method of reacting (A) with the polymer after reacting (B) and (C)”, all of the isocyanate groups of the polyisocyanate (B) are (meth) acrylate (C). Urethane (meth) acrylate (by-product) that reacts with the hydroxyl group of is formed. Since this by-product does not contain the polyol (A) skeleton, it not only exhibits crystallinity but also has a low transmittance at 400 nm and is highly likely to gel.

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 the polyol (A) and the polyisocyanate (B) are mixed together and reacted.
[Method 2] A method in which the polyol (A) is reacted while being dropped into the polyisocyanate (B).
[Method 3] A method in which the polyisocyanate (B) is reacted while being dropped into the polyol (A).

  In the case of [Method 1], the reactor is charged with the polyol (A) and the polyisocyanate (B) and stirred until uniform. Thereafter, a method of starting urethanization by adding a urethanization catalyst after raising the temperature as necessary while stirring is desirable. The temperature may be increased as necessary after adding the urethanization catalyst.

  In [Method 1], (meth) acrylate (Y) may be used as a compatibilizing agent. In this case, the polyol (A) is charged into the reactor together with the (meth) acrylate (Y) and stirred until uniform, and then the polyisocyanate (B) is charged and made uniform. As a result, the viscosity of the reaction solution can be further reduced. Thereafter, a method of starting urethanization by adding a urethanization catalyst after raising the temperature as necessary while stirring is desirable. The temperature may be increased as necessary after adding the urethanization catalyst.

  When the urethanization catalyst is added before the polyol (A) and the polyisocyanate (B) are uniformly stirred, the urethanization reaction proceeds non-uniformly, resulting in gelation of the resulting urethane prepolymer. Tend to occur. Furthermore, the reaction may be terminated with unreacted polyisocyanate (B) remaining in the system. In this case, the transmittance at 400 nm is lowered due to a by-product obtained by the reaction of (meth) acrylate (C) to be reacted later with the remaining polyisocyanate (B), which is not preferable.

  The content of such a by-product is preferably less than 7% by weight with respect to the target urethane prepolymer. If it is 7% by weight or more, the transmittance at 400 nm is remarkably lowered.

  [Method 1] is industrially excellent in that the polyol (A) having a high viscosity is charged in a reactor as it is and a urethane prepolymer can be produced in one pot. Moreover, since urethanization is started from the state in which the polyol (A) and the polyisocyanate (B) are uniformly mixed, this is excellent in that the reaction according to the stoichiometry proceeds. Furthermore, 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 production reproducibility is high. On the other hand, as in [Method 2] and [Method 3] to be described later, in the method in which either the polyol (A) or the polyisocyanate (B) is dropped and urethanized, the reaction species in the system are changed depending on the dropping time. Since the ratio is different, it is disadvantageous in 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], the polyisocyanate (B) and the urethanization catalyst are charged into the reactor, and the mixture is stirred until it is uniform. The temperature is raised as necessary, and the reaction is performed while dropping the polyol (A). And

  In [Method 2], (meth) acrylate (Y) may be used as a compatibilizing agent. Specifically, polyisocyanate (B), urethanization catalyst, and (meth) acrylate (Y) are charged and stirred until uniform. Then, it heats as needed, and is made to react, dripping the uniform mixed liquid of a polyol (A) or polyol (A) and (meth) acrylate (Y).

  In the case of [Method 3], the polyol (A) and the urethanization catalyst are charged into a reactor, and the mixture is stirred until it is uniform. The temperature is raised as necessary, and the polyisocyanate (B) is reacted while dropping. And

  In [Method 3], (meth) acrylate (Y) may be used as a compatibilizing agent. Specifically, the polyol (A), the urethanization catalyst, and the (meth) acrylate (Y) are charged and stirred until uniform. Then, it heats as needed, and is made to react, dripping the uniform mixed liquid of polyisocyanate (B) or polyisocyanate (B) and (meth) acrylate (Y).

In the case of [Method 3], since the polyisocyanate (B) is reacted in a large amount of the polyol (A) while dropping, the isocyanate group of the polyisocyanate (B) urethanizes 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 a hydroxyl group at both ends of the ABA type as a by-product is written as a by-product. When the polyisocyanate (B) (diisocyanate) reacts and is schematically written, a compound having both ends of the B-A-B-A-B type having an isocyanate group as a by-product is generated, and a similar reaction is repeated. In general, a large amount of compounds with the following structure may be by-produced.
B- [AB] _n -AB (n = 1 or greater integer)

  When such by-products are by-produced in large quantities, urethane (meth) acrylate obtained by reacting (meth) acrylate (C) has a low acrylic density, so the cured product cannot obtain a sufficient crosslinking density, Hardness will fall.

  [Method 2] may produce the by-product described in [Method 3], but its amount tends to be small. In the case of [Method 2], the viscosity of the obtained urethane prepolymer tends to be low.

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

  In any method, when the urethane prepolymer is formed by the reaction with the polyol (A) and the polyisocyanate (B), the reaction is preferably performed until all the hydroxyl groups in the reaction solution are urethanized.

  The end point of the reaction is the measurement of the isocyanate group concentration in the reaction solution, and all of the hydroxyl groups charged into the system were below the isocyanate group concentration when urethane was converted, the isocyanate group concentration no longer changed, etc. Can be confirmed.

  From the above viewpoint, the molar ratio of the hydroxyl group of the polyol (A) and the isocyanate group of the polyisocyanate (B) is not particularly limited. For example, the isocyanate group is 1.1 to 2.0 mol, preferably 1 mol to 1 mol of the hydroxyl group. 1.1 to 1.4 mol can be used.

  When a urethane prepolymer and (meth) acrylate (C) are reacted to produce the target urethane (meth) acrylate (X), if a large amount of unreacted isocyanate groups remain, gelation occurs, Problems such as poor curing of the coating 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 hydroxyl group of (meth) acrylate (C) is excessive with respect to the number of moles of isocyanate group of the urethane prepolymer. It is necessary to continue the reaction until the residual isocyanate group concentration reaches 0.05% by weight or less. In the above reaction, the number of moles of the hydroxyl group of the (meth) acrylate (C) is 1.0 to 1.1 moles, preferably 1.0 to the mole number of 1 mole of isocyanate groups of the urethane prepolymer. The amount can be 1.05 mol. In addition, when using alcohol (D), it is preferable that the total amount of the number-of-moles of the hydroxyl group of (meth) acrylate (C) and alcohol (D) is contained in the said range.

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

  In the manufacturing method of urethane (meth) acrylate (X) of this invention, it is preferable to carry out in molecular oxygen containing gas atmosphere. The oxygen concentration is appropriately selected in consideration of safety.

  In the method for producing the 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 or 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) to be produced. When the addition amount of the catalyst is less than 1 ppm, a sufficient reaction rate may not be obtained. When the addition amount is more than 3000 ppm, there is a risk of adversely affecting various physical properties of the product 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 production of urethane (meth) acrylate (X). Moreover, after apply | coating the volatile organic solvent which remained in the active energy ray-curable composition to the transparent base material, it can also be removed by pressure reduction (drying). In addition, a volatile organic solvent means the organic solvent whose boiling point does not exceed 200 degreeC.

  However, from the production of urethane (meth) acrylate (X) to the blending of the active energy ray curable composition, it is possible to prepare the active energy ray curable composition without using any volatile organic solvent. Is preferable in the curing system. That is, it is preferable that the active energy ray-curable composition of the present invention does not contain a volatile organic solvent. Here, “does not contain” means that the proportion of the entire active energy ray-curable composition is 1% by weight or less, preferably 0.5% by weight or less, and 0.1% by weight. % Or less is more preferable.

  In the method for producing urethane (meth) acrylate (X) of the present invention, the reaction is preferably performed at a temperature of 130 ° C. or less, and more preferably 40 to 130 ° C. When the temperature is lower than 40 ° C., a practically sufficient reaction rate may not be obtained. When the temperature is higher than 130 ° C., the double bond portion may be cross-linked by radical polymerization due to heat, and a gelled product may be generated.

  When the urethane prepolymer of the present invention is formed, the urethane prepolymer is reacted until the isocyanate group concentration in the reaction solution is equal to or lower than the remaining isocyanate group concentration when all of the hydroxyl groups subjected to the reaction are urethaned. Is preferably formed. The residual isocyanate group concentration can be analyzed by gas chromatography, titration method or the like.

  The isocyanate group concentration in the reaction liquid when producing urethane (meth) acrylate (X) from the urethane prepolymer is usually carried out until the residual isocyanate group is 0.1% by weight or less. The residual isocyanate group concentration is analyzed by gas chromatography, titration method or the like.

  In order to adjust the concentration of the (meth) acryloyl group of the 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, wettability with a substrate can be adjusted.

  The “(meth) acryloyl group concentration” can be calculated by applying the following formula.

[Calculation formula of (meth) acryloyl group concentration]
“(Meth) acryloyl group concentration (mol / kg)” = “weight of (meth) acrylate (C) (g)” × “(meth) acryloyl group number in (meth) acrylate (C) molecule” ÷ “(meta ) Molecular weight of acrylate (C) ”× 1000 ÷“ weight of urethane (meth) acrylate (X) to be produced (g) ”

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

  In the present invention, the concentration of the (meth) acryloyl group of the 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.

  When the (meth) acryloyl group concentration is less than 0.05 mol / kg, there is a risk of insufficient curing even when irradiated with active energy rays, and the initial adhesion to the substrate is reduced due to a decrease in cohesive strength. This is not preferable. Moreover, since the heat resistance of hardened | cured material falls when a (meth) acryloyl group density | concentration exceeds 0.80 mol / kg, it is unpreferable. Specifically, when this cured product is tested under conditions of 95 ° C. and 1000 hours, it causes an increase in coating film hardness, resulting in a decrease in adhesion to the substrate and a shrinkage in curing. It is a problem that the shape of the coating film changes.

[Monofunctional (meth) acrylate (Y)]
By containing the monofunctional (meth) acrylate (Y), the active energy ray-curable composition of the present invention can accurately adjust the viscosity and adjust the Tg of the cured coating film when producing urethane (meth) acrylate. The effect of preventing the increase in viscosity, the appearance of the resin, the suppression of by-products, the transparency of the cured product, the heat resistance and the like is achieved. Monofunctional (meth) acrylate refers to (meth) acrylate having one acryloyl group in the molecule.

  As described above, (meth) acrylate (Y) may be used as a compatibilizing agent when forming the urethane prepolymer. By using (meth) acrylate (Y) as a compatibilizing agent, raw materials (for example, polyol (A) and polyisocyanate (B)) can be compatibilized. In addition, when the urethane prepolymer is formed, the viscosity of the reaction solution may increase, but at that time, it also acts as a so-called diluent that alleviates the increase in viscosity. Furthermore, since it is possible to omit the work of adding (meth) acrylate (Y) to the urethane prepolymer by using it when forming the urethane prepolymer, the working efficiency is improved.

  Although the usage-amount of (meth) acrylate (Y) is not specifically limited, For example, 5-60 with respect to the total amount (100 weight%) of urethane (meth) acrylate (X) and (meth) acrylate (Y). % By weight, preferably 10 to 50% by weight. If it is less than 5 weight%, the viscosity of the urethane (meth) acrylate obtained becomes high, handling becomes difficult, and gelation may occur. On the other hand, when it exceeds 60% by weight, when applied, the viscosity is too low and the wettability with the transparent substrate is deteriorated, which may reduce the flexibility and heat resistance of the urethane (meth) acrylate.

  Such a monofunctional (meth) acrylate is not particularly limited, but is preferably a monofunctional (meth) acrylate that is not a polyether acrylate (a PO-modified product, an EO-modified product, etc.) 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 ( (Meth) acrylate, isobornyl (meth) acrylate, octyl / decyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, isodecyl (meth) acrylate, -Lauryl (meth) acrylate, n-stearyl (meth) acrylate, cyclhexyl (meth) acrylate, other alkyl (meth) acrylates, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (Meth) acrylate and the like can be mentioned, and n-octyl (meth) acrylate, isobornyl (meth) acrylate and octyl / decyl (meth) acrylate are preferable, and n-octyl (meth) acrylate is particularly preferable. In addition, you may use 2 or more types of monofunctional (meth) acrylate together according to the objective.

  Commercially available products may be used as the monofunctional (meth) acrylate, for example, the product name “β-CEA” (manufactured by Daicel Ornex Co., Ltd., β-carboxyethyl acrylate), and the product name “IBOA” (Daicel Ornex). The product name "ODA-N" (manufactured by Daicel Ornex, octyl / decyl acrylate), product name "NOA" (manufactured by Osaka Organic Chemicals, normal octyl acrylate), etc. are available from the market. 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 a known photoradical polymerization initiator or photocationic polymerization initiation. For example, 1-hydroxycyclohexyl phenyl 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-methylpropan-1-one, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) Ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1, benzoin, Zoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzyldimethyl ketal, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4 -Benzoyl-4'-methyldiphenyl sulfide, 3,3'-dimethyl-4-methoxybenzophenone, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2,4,6-trimethylbenzoyl Examples include diphenylphosphine oxide, methylphenylglyoxylate, benzyl, camphorquinone and the like. Two or more photopolymerization initiators may be used in combination depending on the purpose.

  Although the usage-amount of a photoinitiator is not specifically limited, For example, it is preferable that it is 1-20 weight part with respect to 100 weight part of resin total amount of an active energy ray-curable composition, More preferably, it is 1-5 weight Part. If the amount of the photopolymerization initiator used is less than 1 part by weight, it may cause curing failure. Conversely, if the amount of the photopolymerization initiator used is large, an odor derived from the photopolymerization initiator remains from the cured coating film. There are things 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 The above (meth) acrylate etc. are pointed out. Note that the photopolymerization initiator (Z) and the solvent do not correspond to the resin component.

  The active energy ray-curable composition of the present invention may further contain various additives as necessary. Examples of such additives include fillers, dyes and pigments, leveling agents, ultraviolet absorbers, light stabilizers, antifoaming agents, dispersants, and thixotropic agents. Although the compounding quantity of these additives is not specifically limited, It is preferable that it is 0-10 weight part with respect to 100 weight part of resin total amount of an active energy ray-curable composition, More preferably, it is 0.05-5. Parts by weight.

  Since the active energy ray-curable composition of the present invention is highly compatible with other components that can be contained in a composition such as a bifunctional or higher functional (meth) acrylate, the viscosity can be easily adjusted. Moreover, the target characteristic (for example, hardness, deformation resistance, a softness | flexibility) can be easily provided to the hardened | cured material.

[Bifunctional or higher (meth) acrylate]
Although it does not specifically limit as (meth) acrylate more than bifunctional, (meth) acryloyl group is 2 in molecules, such as 1, 6- hexanediol diacrylate, trimethylol propane triacrylate, and tricyclodecane dimethanol diacrylate. The compound which has the above is mentioned. The active energy ray-curable composition of the present invention may contain the bifunctional or higher functional (meth) acrylate, and the content thereof is not particularly limited, but the total amount of the active energy ray-curable composition (100% by weight). ) To 0.1 to 90% by weight, more preferably 1 to 80% by weight, still more preferably 5 to 60% by weight. Moreover, 0.1-400 weight part is preferable, as for content of bifunctional or more than (meth) acrylate with respect to urethane (meth) acrylate (X) (100 weight part), More preferably, it is 1-300 weight part, More preferably. Is from 3 to 200 parts by weight, most preferably from 5 to 150 parts by weight.

<Laminate>
The laminate of the present invention comprises a cured product layer of the active energy ray-curable composition between a first transparent substrate selected from glass and plastic and a second transparent substrate selected from glass and plastic. There is no particular limitation as long as it has a laminate. Preferably, the active energy ray-curable composition is applied onto the first transparent substrate to form a resin layer, and the second transparent substrate is adhered onto the resin layer. For example, by irradiating an active energy ray such as an ultraviolet ray or an electron beam through the material, the active energy ray-curable composition is cured in a very short time to form a cured product layer to obtain a laminate. Can do. FIG. 1 shows an embodiment of the laminate.

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

  As the plastic substrate, it is possible to use an existing transparent material, and is not particularly limited. For example, polyolefin resin such as polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyethylene terephthalate, Examples thereof include polyester resins such as polyethylene naphthalate and polybutylene terephthalate, acrylic resins, and polycarbonate resins. Among these, polycarbonate resin and acrylic resin are particularly preferably used.

[Applying, pouring and curing methods on transparent substrates]
When applying the active energy ray-curable composition of the present invention to a transparent substrate (for example, a glass substrate such as a glass plate or a plastic substrate such as a plastic film), the application method is not particularly limited and spraying is performed. A method, an airless spray method, an air spray method, a roll coat method, a bar coat method, a gravure method, or the like can be used. Among these, the roll coat method is most preferably used from the viewpoints of aesthetics, cost, workability, and the like. The application may be a so-called in-line coating method performed during the manufacturing process of a plastic film or the like, or a so-called off-line coating method in which coating is performed in a separate process on an already manufactured transparent substrate. From the viewpoint of production efficiency, off-line coating is preferred. In addition, it is preferable to use a cartridge in order to prevent bubbles from being generated.

  30-300 micrometers is preferable and, as for the thickness of the hardened | cured material layer in the laminated body of this invention, More preferably, it is 50-200 micrometers. When the layer thickness exceeds 300 μm, the amount of the resin composition to be applied becomes large, so that the cost may increase or the uniformity of the film thickness may decrease. Moreover, when it is less than 30 micrometers, the softness | flexibility characteristic of curable resin cannot be exhibited.

  The light source for performing ultraviolet irradiation is not particularly limited, and for example, a high pressure mercury lamp, an ultrahigh 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 the light source, the distance between the light source and the coating surface, and other conditions, but is several tens of seconds at most, and 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 set the irradiation amount to 2 to 5 Mrad. After irradiation with active energy rays, curing may be promoted by heating as necessary.

<Use of active energy ray-curable composition>
Although the active energy ray-curable composition of the present invention can be used as an interlayer filler (a curable composition for interlayer filling) as described above, other than that, an adhesive composition and a coating composition, particularly an optical member. Or it can use as a composition for adhesives used for an optical film, or a composition for coating agents.

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

<Measuring method of physical properties, testing method, evaluation method>
The physical property measurement method, test method, and evaluation method are shown below.
[Measurement of weight average molecular weight]
The weight average molecular weight of urethane (meth) acrylate and the like was determined by GPC (gel permeation gas chromatography) method based on standard polystyrene under the following measurement conditions. In addition, the weight average molecular weight of urethane (meth) acrylate in Table 1 described two significant figures.
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 In-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. (minus 30 ° C.) for 1 hour, and the presence or absence of white turbidity or coloring due to crystallization or the like was visually evaluated according to the following criteria.

  Specifically, when neither white turbidity nor coloring can be recognized by visual inspection, the result is good (clear), and “◯” is described in the “resin appearance” column of Table 2. On the other hand, when either white turbidity or coloring was visually confirmed, “x” was entered in the column of “resin appearance” in Table 2 assuming that the result was defective (appearance defect).

[Compatibility test with bifunctional monomer]
In the resin composition before curing, 1,6-hexanediol diacrylate (manufactured by Daicel Ornex Co., Ltd., product name HDDA) is made to have the same weight ratio as the urethane (meth) acrylate-containing material contained in the resin composition. In addition, a test solution was obtained. A test solution was obtained in the same manner except that 1,6-hexanediol diacrylate was replaced with tricyclodecane dimethanol diacrylate (manufactured by Daicel Ornex Co., Ltd., product name IRR214K).

  About both test solutions, cloudiness and isolation | separation were confirmed visually. When neither cloudiness nor separation could be confirmed, the result was good (clear), and “◯” was entered in the “Compatibility” column of Table 2. When one or both of the monomer solutions are visually recognized as either cloudy or separated, it is determined that the result is defective (defective appearance), and “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 with silicon rubber on a microglass (dimension: 1.0 × 76 × 26 mm) (inner dimension: 1.0 × 40 × 10 mm), 1.0 g of the active energy ray-curable composition was dropped. When the surface was smoothened by heating at 70 ° C., ultraviolet irradiation was performed under the following conditions.

(UV irradiation conditions)
Irradiation intensity: 120 W / cm
Irradiation distance: 10cm
Conveyor speed: 5 m / min Irradiation frequency: 2 times

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

  When the transmittance at 400 nm was 95% or more, the transmittance was good, and “◯” was described in the “Transparency” column of Table 2. On the other hand, when the transmittance at 400 nm was less than 95%, the transmittance was judged as poor, and “X” was entered 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 resistance conditions, and the APHA (hue) and shape change of the test piece A were observed. In addition, (A) of FIG. 3 is the figure which looked at the glass laminated body from the top, (B) of the figure is the figure which looked at the glass laminated body from the side.

(Preparation of specimen A)
A 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 on the center of a glass plate (thickness 1 mm, 5 cm square). Furthermore, the glass plate of the same shape was covered from the top, the resin layer was extended circularly (4 cm diameter), and the glass laminated body was obtained. Thereafter, a glass laminate (test piece A) having a cured resin composition layer is irradiated from the glass surface of one side of the glass laminate using a high-pressure mercury lamp (made by Eye Graphics Co., Ltd.) under the following conditions. Got.

(UV irradiation conditions)
Irradiation intensity: 120 W / cm
Irradiation distance: 10cm
Conveyor speed: 5 m / min Irradiation frequency: 8 times (4 times on both sides)

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

(Measurement of APHA)
APHA is measured using a spectroscopic color meter (product name: Spectro Color Meter SE2000, manufactured by Nippon Denshoku Industries Co., Ltd.) by measuring APHA of the glass laminate before and after storage under heat-resistant conditions, and evaluated 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, 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, the heat resistance is poor from the viewpoint of hue, and “x” is entered in the “hue change” column of “heat resistance” in Table 2. Described.

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

  Specifically, when a shape change (any shape change such as warpage, wrinkle generation, pattern board displacement, etc.) cannot be recognized visually, it is assumed that the result is good and “heat resistance” in Table 2 “ “◯” is described in the “shape change” column. On the other hand, when the shape change was recognized visually, the result was judged to be bad, 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 made of silicon rubber on a glass (dimension: 2 × 100 × 200 mm) plate (internal dimension: 7 × 40 × 40 mm), and active energy ray curable in advance in the frame. The composition was slowly added so as not to generate bubbles as much as possible. When air bubbles were conspicuous, they were removed by putting them in an oven at 80 ° C. Then, it heated at 80 degreeC, and when the surface became smooth, ultraviolet irradiation was performed on the following conditions, the coating film was turned inside out, and ultraviolet rays were irradiated on the same conditions, and the test piece B was obtained.

(UV irradiation conditions)
Irradiation intensity: 120 W / cm
Irradiation distance: 10cm
Conveyor speed: 3.5m / min Irradiation frequency: 5 times

  The A hardness of the test piece B was measured according to JIS K 6253 using an automatic constant pressure loader (GS-610, manufactured by Teclock Co., Ltd.). The load at the time of measurement was 500 g, and the load drop rate was 9 mm / s. Thereafter, the test piece B was stored for 1000 hours at a temperature of 95 ° C. If the numerical value of hardness before and after storage was less than ± 20%, “◯” was entered in the “Hardness change” column of “Heat resistance” in Table 2. On the other hand, if the numerical 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 “numerical value of hardness” 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>
Synthesis examples and examples of urethane (meth) acrylate (X) will be described below.

[Measurement of isocyanate group concentration]
The isocyanate group concentration was measured as follows. In addition, the measurement was performed under stirring with a stirrer in a 100 mL glass flask.

(Blank value measurement)
To 15 mL of THF, add 15 mL of dibutylamine in THF (0.1 N), add 3 drops of bromophenol blue (1% methanol dilution), and add blue color. Titration with an aqueous HCl solution. The titration amount of the aqueous HCl solution when the color change was observed was defined as V _b (mL).

(Measurement of measured isocyanate group concentration)
The sample was weighed W _s (g), dissolved in 15 mL of THF, and 15 mL of a dibutylamine THF solution (0.1 N) was added. After confirming that the solution was formed, 3 drops of bromophenol blue (diluted in 1% methanol) was added to give a blue color, followed by titration with an aqueous HCl solution having a normality of 0.1N. The titer of the aqueous HCl solution when the color change was observed was defined as V _s (mL).
The isocyanate group concentration in the sample was calculated by the following calculation 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 examples and comparative synthesis examples will be described.

[Polyol (A)]
“Pripol 2033” (compound name hydrogenated dimer diol, hydroxyl value 210 mg KOH / g, weight average molecular weight 534); product name “Pripol 2033-LQ- (GD)” (manufactured by Croda 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 Croda 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 Croda Japan)
“PT-2001” (compound name: polypropylene glycol, hydroxyl value: 57.1 mg KOH / g, weight average molecular weight: 1964); product name “Sanix PT-2001” (manufactured by Sanyo Chemical Industries)
“P3000” (compound name hydrogenated polybutadiene glycol, hydroxyl value 0.56 Phth meq / g (phthalic anhydride equivalent), non-volatile content 99.98%, weight average molecular weight 3571); product name “KRASOL HLBH P3000” (Nippon Soda) (Made by company)
“PP400” (compound name: polypropylene glycol, hydroxyl value: 277 mg KOH / g, weight average molecular weight: 404); product name “Sanix PP400” (manufactured by Sanyo Chemical Industries)

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

[(Meth) 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.)

[(Meth) 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-hydroxycyclohexyl phenyl ketone); product name “Irg184” (manufactured by BASF Japan Ltd.)

  Synthesis examples and comparative synthesis examples are described below. The concentration notation “ppm”, “% by weight”, and “% by weight” are (theoretical) urethane (meta) unless otherwise specified. ) Concentration relative to the entire acrylate-containing material.

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

  In addition, the completion of the reaction is that the isocyanate group concentration in the reaction solution is equal to or less than the residual isocyanate group concentration (hereinafter referred to as “theoretical end-point isocyanate group concentration”) when all of the hydroxyl groups subjected to the reaction are urethanized. That was confirmed. In this example, after confirming that the isocyanate group concentration in the reaction solution was equal to or lower than the theoretical end-point isocyanate group concentration (1.73 wt%), the procedure shifted 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. Thereafter, 9.9 g of HEA was added and aged for 3 hours. After confirming that the isocyanate group concentration was less than 0.05% by concentration, the reaction was terminated to obtain a urethane (meth) acrylate-containing material (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. In addition, the (meth) acryloyl group density | concentration of urethane (meth) acrylate was 0.28 mol / kg.

(Synthesis Example 2)
Other than not using TMP and 2-EH, changing the molar ratio of polyisocyanate (B) and (meth) acrylate (C), and further using 20% by weight of NOA as (meth) acrylate (Y) In the same manner as in Synthesis Example 1, a urethane (meth) acrylate-containing product (X-2) was obtained. Note that the molar ratio of Prepol 2033, IPDI, and HEA used in the above reaction was 4.0: 5.0: 2.02. In addition, the (meth) acryloyl group concentration of urethane (meth) acrylate was 0.58 mol / kg.

(Synthesis Example 3)
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 (meth) acrylate (Y). Moreover, the (meth) acryloyl group density | 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 polyisocyanate (B) and the molar ratio of polyol (A) and polyisocyanate (B) was changed. Got. Note that the molar ratio of Prepol 2033, HDI, and HEA used in the above reaction was 5.0: 6.0: 2.02. In addition, the (meth) acryloyl group density | concentration of urethane (meth) acrylate was 0.51 mol / kg.

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

(Comparative Synthesis Example 1)
Instead of Pripol 2033, Preplast 3199 is used as the polyol (A), the molar ratio of the polyol (A) and the polyisocyanate (B) is changed, and 30% by weight of NOA is further added as the (meth) acrylate (Y). Except having used, it carried out similarly to the synthesis example 2, and obtained the urethane (meth) acrylate containing material (CX-1). The molar ratio of Preplast 3199, IPDI, and HEA used in the above reaction was 6.0: 7.0: 2.02. In addition, the (meth) acryloyl group concentration of urethane (meth) acrylate was 0.14 mol / kg.

(Comparative Synthesis Example 2)
In the same manner as in Comparative Synthesis Example 1, except that the molar ratio of the polyol (A) and the polyisocyanate (B) was changed and 20% by weight of NOA was used as the (meth) acrylate (Y), the urethane (meta ) An acrylate-containing product (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)
Compared except that Preplast 3197 was used as the polyol (A), the molar ratio of the polyol (A) and the polyisocyanate (B) was changed, and further 20% by weight of NOA was used as the (meth) acrylate (Y). In the same manner as in Synthesis Example 1, a urethane (meth) acrylate-containing product (CX-3) was obtained. The molar ratio of Preplast 3197, IPDI, and HEA was 3.0: 4.0: 2.02. In addition, the (meth) acryloyl group density | concentration of urethane (meth) acrylate was 0.29 mol / kg.

(Comparative Synthesis Example 4)
Except for using PT-2001 as the polyol (A), changing the molar ratio of the polyol (A) and the polyisocyanate (B), and further using 20% by weight of NOA as the (meth) acrylate (Y). In the same manner as in Comparative Synthesis Example 1, a urethane (meth) acrylate-containing product (CX-4) was obtained. The molar ratio of SANNICS PT-2001, IPDI, and HEA was 4.0: 5.0: 2.02. In addition, the (meth) acryloyl group density | concentration of urethane (meth) acrylate was 0.22 mol / kg.

(Comparative Synthesis Example 5)
Using TMP and P3000 as polyol (A), 2-EH as alcohol (D), changing the molar ratio of polyol (A), polyisocyanate (B) and (meth) acrylate (C), and (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 is used as the polyol (A), the molar ratio of the polyol (A) and the polyisocyanate (B) is changed, and 20% by weight of NOA is used as the (meth) acrylate (Y). In the same manner as in Example 1, a urethane (meth) acrylate-containing product (CX-6) was obtained. The molar ratio of PP400, IPDI, and HEA was 4.0: 5.0: 2.02. In addition, the (meth) acryloyl group density | concentration of urethane (meth) acrylate was 0.23 mol / kg.

  About the structure of the above urethane (meth) acrylate containing material (X-1)-(X-5), (CX-1)-(CX-6), and the (meth) acryloyl group density | concentration of urethane (meth) acrylate, It is described in Table 1. In addition, polyol (A), polyisocyanate (B), (meth) acrylate (C), and alcohol (D), which are constituent components of urethane (meth) acrylate in the table, describe the respective molar ratios. , (Meth) acrylate (Y) indicates the concentration (%) relative to the entire urethane (meth) acrylate-containing material.

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

(Preparation of active energy ray-curable composition)
100 parts by weight of urethane (meth) acrylate-containing materials (X-1) to (X-5) and (CX-1) to (CX-6) are added with 3 parts by weight of Irg184 as a photopolymerization initiator. Thus, an active energy ray-curable composition was obtained.

<Test results>
The obtained active energy ray-curable composition was subjected to 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 the 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 and good compatibility with the resin before curing. Became. Furthermore, it became clear that the cured product has the performance that the hue change, shape change, and coating film hardness do not change even when subjected to high heat for a long time.

DESCRIPTION OF SYMBOLS 1 Hardened | cured material layer of active energy ray curable composition 2 Transparent base material 3 Transparent base material 4 Silicon rubber 11 Resin 21 Micro glass 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 comprising 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 dimer diol having a weight average molecular weight of 200 to 1,000,
The active energy ray-curable composition, wherein the polyisocyanate (B) is a polyisocyanate containing 50% by weight or more of an aliphatic diisocyanate.   Furthermore, the active energy ray curable composition of Claim 1 containing (meth) acrylate more than bifunctional.   The active energy ray-curable composition according to claim 1 or 2, which is used for interlayer filling.   A cured product layer of the active energy ray-curable composition according to claim 1 or 2, between a first transparent substrate selected from glass and plastic and a second transparent substrate selected from glass and plastic. Laminate having.

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