WO2021199339A1

WO2021199339A1 - Reactive hot-melt adhesive, bonded body and production method for same, and garment

Info

Publication number: WO2021199339A1
Application number: PCT/JP2020/014927
Authority: WO
Inventors: 和樹久野; 淑杰曲; 翔太青柳; 琢磨鈴木; 聡一郎小宮; 和幸馬籠; 卓也今井; 淳一亀井; 晃一斉藤
Original assignee: 昭和電工マテリアルズ株式会社
Priority date: 2020-03-31
Filing date: 2020-03-31
Publication date: 2021-10-07
Also published as: CN115335568A; JPWO2021199339A1

Abstract

A reactive hot-melt adhesive that contains a urethane prepolymer. When C(A) is the integral value of the peak observed at 163–170 ppm during 13C-NMR analysis of the urethane prepolymer, and C(B) is the integral value of the peak observed at 171–176 ppm, C(A) and C(B) satisfy expression (X).　(X) 0.36≤C(A)/(C(A)+C(B)).

Description

Reactive hot melt adhesives, adhesives and methods for their manufacture, and clothing

The present disclosure relates to reactive hot melt adhesives, adhesives and methods for producing them, and clothing.

Since the hot melt adhesive is a solvent-free adhesive, it has less impact on the environment and the human body, and it can be adhered for a short time, so it is suitable for improving productivity. Hot melt adhesives can be broadly divided into two types: those containing a thermoplastic resin as a main component and those containing a reactive resin as a main component. As the reactive resin, a urethane prepolymer having an isocyanate group at the end is mainly used.

The reactive hot melt adhesive containing urethane prepolymer as the main component develops a certain degree of adhesive strength in a short time by cooling and solidifying the adhesive itself after application. After that, the terminal isocyanate group of the urethane prepolymer reacts with moisture (moisture in the air or on the surface of the adherend) to increase the molecular weight, and crosslinks occur to develop heat resistance. Such an adhesive is called a moisture-curable reactive hot melt adhesive. Reactive hot melt adhesives containing urethane prepolymer as the main component show good adhesive strength even when heated.

For example, Patent Document 1 describes a polyol (b) composed of a polyisocyanate (a), an aromatic ring-containing polyether polyol (b1) and / or an aromatic ring-containing polyester polyol (b2), and an aliphatic polyester polyol (b3). Reactive hot melt adhesives made of urethane prepolymers formed from are disclosed.

Japanese Unexamined Patent Publication No. 2008-03568

In recent years, with the diversification of wearable terminals and the like, various reactive hot melt adhesives are being used. By the way, in a reactive hot melt adhesive, there is a trade-off relationship between adhesive strength and elasticity, and it is extremely important to achieve both of these. However, the conventional reactive hot melt adhesive does not yet have sufficient adhesive strength and elasticity, and there is room for further improvement.

Therefore, the main object of the present disclosure is to provide a reactive hot melt adhesive having excellent adhesive strength and excellent elasticity.

In order to solve the above problems, the present inventors ^{conducted a 13-} C-NMR analysis on the urethane prepolymer and investigated the structural units contained in the urethane prepolymer. As a result, the integrated value of the peaks observed in a predetermined range was predetermined. It has been found that the urethane prepolymer having a ratio of 1) tends to have excellent adhesive strength and elasticity, and has completed the invention of the present disclosure.

One aspect of the disclosure relates to reactive hot melt adhesives. The reactive hot melt adhesive contains a urethane prepolymer. For urethane prepolymers, in ¹³ C-NMR analysis, the integral value of the peak observed in the range of 163 to 170 ppm is C (A), and the integral value of the peak observed in the range of 171 to 176 ppm is C (B). Then, C (A) and C (B) satisfy the following formula (X). Such a reactive hot melt adhesive has excellent adhesive strength and elasticity.
0.36 ≤ C (A) / (C (A) + C (B)) (X)

^{The 13} C-NMR analysis in the present specification is performed under the following measurement conditions using ^{AVANCE NEO (probe: CryoProbe TM} ) manufactured by Bruker Japan Co., Ltd. as a nuclear magnetic resonance spectrometer (NMR).
(Measurement condition)
・¹³ C-NMR quantitative spectrum: inverse gate decoupling method ・ Resonance frequency: 100 MHz
・ Waiting time (d1): 5 seconds ・ Solvent: Deuterated chloroform (CDCl ₃ )
-Sample concentration: 100 mg / 0.6 ml-CDCl ₃ and 10 mgCr (acac) ₃ as a relaxation reagent at the same time-Chemical shift standard: Tetramethylsilane (TMS) peak set to 0.00 ppm-Measurement temperature: 23 ° C
・ Cumulative number: 400 times

Regarding how to take the integrated value, for example, it is possible to measure the integrated value for each peak observed in the range of 163 to 170 ppm and set the sum of the integrated values as C (A), but the integrated value is used. Since it is easy to obtain and the arbitrariness can be reduced, the integrated value of the entire range of 163 to 170 ppm can be measured collectively and the integrated value can be designated as C (A) (see, for example, FIGS. 2 and 3). ). The same applies to C (B) and C (C). That is, the integral value of the peak observed in the range of 163 to 170 ppm, the integral value of the peak observed in the range of 171 to 176 ppm, and the integral value of the peak observed in the range of 150 to 155 ppm are 163 to 170 ppm, respectively. Can be the integral value of all peaks, the integral value of all peaks of 171 to 176 ppm, and the integral value of all peaks of 150 to 155 ppm.

The urethane prepolymer may be, for example, a urethane prepolymer having an isocyanate group. A urethane prepolymer having an isocyanate group usually has a polymer chain containing a structural unit derived from a polyol and a structural unit derived from polyisocyanate, and an isocyanate group. The isocyanate group may be bonded to the end of the polymerized chain. ^{13 In the} C-NMR analysis, the peak observed in the range of 160 to 180 ppm is mainly the structural unit derived from the polyol constituting the urethane prepolymer, and the carbonyl group of the ester bond of the structural unit derived from the polyester polyol. It is a peak attributed to a carbon atom. The peak observed in the range of 163 to 170 ppm is the carbon atom of the carbonyl group directly bonded to the carbon atom constituting the aromatic ring among the carbon atoms of the carbonyl group of the ester bond of the polyester polyol (hereinafter, the carbon atom). Is sometimes referred to as "carbon atom (A)"), and the peak observed in the range of 171 to 176 ppm is an aliphatic group of carbon atoms of the carbonyl group of the ester bond of the polyester polyol. It is a peak assigned to a carbon atom of a carbonyl group (hereinafter, the carbon atom may be referred to as "carbon atom (B)") which is directly bonded to a carbon atom constituting the group. The carbon atom (A) can be, for example, a carbon atom represented by the following formula (1), and the carbon atom (B) can be, for example, a carbon atom represented by the following formula (2). The integral value of the peak attributed to the carbon atom of the carbonyl group of the ester bond of the structural unit derived from the polyester polyol (corresponding to the above (C (A) + C (B))) is assigned to the carbon atom (A). It can be the sum of the integrated value of the peaks (corresponding to C (A) above) and the integrated value of the peaks attributed to the carbon atom (B) (corresponding to C (B) above). Therefore, C (A) / (C (A) + C (B)) in the above formula (X) is the carbon atom (A) with respect to the sum of the total amount of carbon atoms (A) and the total amount of carbon atoms (B). It means the ratio of the total amount of carbon atoms (the sum of the total amount of carbon atoms (A) / the total amount of carbon atoms (A) and the total amount of carbon atoms (B)). The larger C (A) / (C (A) + C (B)), the larger the proportion of carbon atom (A) in the structural unit derived from the polyester polyol constituting the urethane prepolymer (that is, it is contained in the polyester polyol). It can be said that the proportion of aromatic rings is large).

The polyester polyol can be a polycondensation reaction product of a polyhydric alcohol and a polycarboxylic acid. In this case, the carbon atom (A) and the carbon atom (B) are carbon atoms derived from a polycarboxylic acid. The carbon atom (A) is a carbon atom of a carbonyl group (of the carboxylic acid) that is directly bonded to the carbon atom constituting the aromatic ring among the carbon atoms derived from the polycarboxylic acid. The carbon atom (B) is a carbon atom of a carbonyl group (of a carboxylic acid) that is directly bonded to a carbon atom constituting an aliphatic group among carbon atoms derived from polycarboxylic acid. C (A) / (C (A) + C (B)) in the formula (X) is mainly derived from the type, content, and polycarboxylic acid of the polycarboxylic acid constituting the structural unit derived from the polyester polyol. It tends to be possible to adjust by changing the type, content, etc. of the polyester polyol to be produced.

For urethane prepolymers, C (A) and C (C) have the following formula (Y), where C (C) is the integral value of the peaks observed in the range of 150 to 155 ppm ^{in 13 C-NMR analysis.} It may be satisfied.
3.6 ≤ C (A) / C (C) (Y)

^{13 In} C-NMR analysis, the peak observed in the range of 160 to 180 ppm is mainly the carbon atom of the carbonyl group of the urethane bond formed by the reaction between the polyol of the urethane prepolymer and the polyisocyanate (hereinafter, the carbon). The atom is sometimes referred to as a "carbon atom (C)"). The carbon atom (C) can be, for example, a carbon atom represented by the following formula (3). C (A) / C (C) in the above formula (Y) is the ratio of the total amount of carbon atoms (A) to the total amount of carbon atoms (C) (total amount of carbon atoms (A) / carbon atom (C). Total amount). The larger C (A) / C (C), the larger the ratio of carbon atoms (A) per carbon atom (C) in the urethane prepolymer (that is, the aroma contained in the polyester polyol per urethane bond). It can be said that the ratio of rings is large). C (A) / C (C) in the formula (Y) is a structural unit mainly derived from a polyester polyol, like C (A) / (C (A) + C (B)) in the formula (X). It tends to be possible to adjust by changing the type and content of the polycarboxylic acid constituting the above, the type and content of the polyester polyol derived from the polycarboxylic acid, and the like.

Another aspect of the disclosure relates to reactive hot melt adhesives. The reactive hot melt adhesive contains a urethane prepolymer having a polymer chain containing a structural unit derived from a polyol and a structural unit derived from polyisocyanate, and an isocyanate group bonded to the end of the polymer chain. For urethane prepolymers, in ¹³ C-NMR analysis, the integral value of the peak observed in the range of 163 to 170 ppm is C (A), and the integral value of the peak observed in the range of 150 to 155 ppm is C (C). Then, C (A) and C (C) satisfy the following formula (Y). Such a reactive hot melt adhesive has excellent adhesive strength and elasticity.
3.6 ≤ C (A) / C (C) (Y)

The structural unit derived from the polyol may include a structural unit derived from a polyester polyol having an aromatic ring.

The reactive hot melt adhesive may be used to bond a plurality of adherends selected from cloth and paper to each other. Here, the combination of the adherends may be cloth and cloth, paper and paper, or cloth and paper. The present disclosure further applies the above urethane prepolymer-containing composition as a reactive hot melt adhesive used to bond a plurality of adherends selected from cloth and paper to each other, or cloth. And applications for the manufacture of reactive hot melt adhesives used to bond a plurality of adherends selected from paper to each other.

Another aspect of this disclosure relates to an adhesive. The adhesive body includes a first adherend, a second adherend, and an adhesive layer that adheres the first adherend and the second adherend to each other. The adhesive layer contains a cured product of the above reactive hot melt adhesive.

Another aspect of this disclosure concerns clothing. The garment includes the above-mentioned adhesive body, and the first adherend and the second adherend may be cloth. The garment may be non-sewn garment.

Another aspect of the present disclosure relates to a method for manufacturing an adhesive. The method for producing the adhesive includes a step of forming an adhesive layer by melting the above-mentioned reactive hot melt adhesive and applying it to a first adherend, and a second coating on the adhesive layer. It includes a step of arranging the adherends and crimping the second adherend to obtain a laminate, and a step of curing the adhesive layer in the laminate to obtain an adhesive.

According to the present disclosure, a reactive hot melt adhesive having excellent adhesive strength and excellent elasticity is provided. Further, according to the present disclosure, there is provided an adhesive using such a reactive hot melt adhesive and a method for producing the same. Further, according to the present disclosure, garments provided with an adhesive are provided.

FIG. 1 is a schematic view showing a method for manufacturing an adhesive according to an embodiment, and FIGS. 1 (a), (b), (c), and (d) are schematic views showing each step. ^{FIG. 2 is a 13} C-NMR spectrum of the urethane prepolymer B of Production Example 2 in the range of 150 to 180 ppm. ^{FIG. 3 is a 13} C-NMR spectrum of the urethane prepolymer E of Production Example 5 in the range of 150 to 180 ppm.

Hereinafter, the mode for implementing the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments.

In the present specification, "polyol" means a compound having two or more hydroxy groups in the molecule.

In the present specification, "polyisocyanate" means a compound having two or more isocyanate groups in the molecule.

In the present specification, the determination of "amorphous" and "crystalline" can be made based on the presence or absence of the melting point (Tm) (endothermic peak associated with melting at DSC), and "crystalline" is defined as the melting point (Crystal). Those having Tm) and "amorphous" are those having no melting point (Tm). In the present specification, "amorphous polyester polyol" means a polyester polyol having a melting point (Tm), and "crystalline polyester polyol" means a polyester polyol having a melting point (Tm).

[Reactive hot melt adhesive]
The reactive hot melt adhesive of one embodiment contains a urethane prepolymer. In general, a reactive hot melt adhesive is capable of exhibiting adhesive strength and the like by increasing the molecular weight by a chemical reaction. In particular, since the urethane prepolymer having an isocyanate group cures (forms a cured product) by reacting with moisture, the urethane prepolymer alone can act as a reactive hot melt adhesive, but the reactive hot melt adhesive can be used. The agent may contain a component other than the urethane prepolymer.

<Urethane prepolymer>
The urethane prepolymer may be, for example, a urethane prepolymer having an isocyanate group. A urethane prepolymer having an isocyanate group usually has a polymer chain containing a structural unit derived from a polyol and a structural unit derived from polyisocyanate, and an isocyanate group. The isocyanate group may be bonded to the end of the polymerized chain. The structural unit derived from the polyol may include a structural unit derived from the polyester polyol. A urethane prepolymer having a structural unit derived from a polyester polyol can usually be obtained by reacting a polyol containing a polyester polyol with a polyisocyanate. That is, the urethane prepolymer may be a reaction product of a polyol containing a polyester polyol and a polyisocyanate. The content of the constituent unit can be adjusted by changing the mixing ratio of the polyester polyol giving the constituent unit and the polyol other than the polyester polyol giving the constituent unit. Further, since a urethane bond is formed by the reaction of the polyol and the polyisocyanate, the polymerized chain of the urethane prepolymer may have a urethane bond. Further, by increasing the equivalent of polyisocyanate with respect to the equivalent of polyol, an isocyanate group can be introduced at the end of the polymerized chain.

For urethane prepolymers, in ¹³ C-NMR analysis, the integral value of the peak observed in the range of 163 to 170 ppm is C (A), and the integral value of the peak observed in the range of 171 to 176 ppm is C (B). Then, C (A) and C (B) satisfy the following formula (X). Such a reactive hot melt adhesive containing a urethane prepolymer has excellent adhesive strength and excellent elasticity.
0.36 ≤ C (A) / (C (A) + C (B)) (X)

C (A) / (C (A) + C (B)) is the ratio of the total amount of carbon atoms (A) to the sum of the total amount of carbon atoms (A) and the total amount of carbon atoms (B) (carbon atoms (A)). ) / The sum of the total amount of carbon atoms (A) and the total amount of carbon atoms (B)). The larger C (A) / (C (A) + C (B)), the larger the proportion of carbon atom (A) in the structural unit derived from the polyester polyol constituting the urethane prepolymer (that is, it is contained in the polyester polyol). It can be said that the proportion of aromatic rings is large).

C (A) / (C (A) + C (B)) is 0.36 or more, and may be 0.38 or more, or 0.40 or more. When C (A) / (C (A) + C (B)) is 0.36 or more, the reactive hot melt adhesive tends to have excellent adhesive strength and excellent elasticity. The upper limit of C (A) / (C (A) + C (B)) is 1.00 or less, 0.95 or less, 0.90 or less, 0.85 or less, 0.80 or less because it is superior in adhesive strength. , 0.75 or less, 0.70 or less, 0.65 or less, or 0.60 or less.

C (A) / C (C) means the ratio of the total amount of carbon atoms (A) to the total amount of carbon atoms (C) (total amount of carbon atoms (A) / total amount of carbon atoms (C)). The larger C (A) / C (C), the larger the ratio of carbon atoms (A) per carbon atom (C) in the urethane prepolymer (that is, the aroma contained in the polyester polyol per urethane bond). It can be said that the ratio of rings is large).

C (A) / C (C) may be 3.6 or more, and may be 3.8 or more or 4.0 or more. When C (A) / C (C) is 3.6 or more, the reactive hot melt adhesive tends to be more excellent in adhesive strength and more excellent in elasticity. The upper limit of C (A) / C (C) may be 10 or less, 8 or less, 7 or less, 6.5 or less, or 6 or less because the adhesive strength is more excellent.

C (A) / (C (A) + C (B)) in the formula (X) and C (A) / C (C) in the formula (Y) mainly constitute a structural unit derived from a polyester polyol. It tends to be possible to adjust by changing the type and content of the polycarboxylic acid, the type and content of the polyester polyol derived from the polycarboxylic acid, and the like. The type, content, and the like of the structural unit derived from the polyol are not particularly limited as long as the urethane prepolymer satisfies the formula (X) and further the formula (Y). According to the study by the present inventors, when the ratio of the structural unit derived from the polyol to the structural unit derived from the polyester polyol having an aromatic ring is large, the urethane prepolymer easily satisfies the formulas (X) and (Y). I found that there was a tendency. Hereinafter, the polyol and polyisocyanate constituting the urethane prepolymer will be described by taking the urethane prepolymer containing such a structural unit as an example.

Component (a): Polyol The structural unit derived from the component (a) may be referred to as a polyester polyol having an aromatic ring (hereinafter, “component (a1))”. ) Is included. The structural unit derived from the component (a) may further include a structural unit derived from a polyol other than the polyester polyol having an aromatic ring (hereinafter, may be referred to as “component (a2)”).

The polyester polyol having an aromatic ring may be a crystalline polyester polyol having a melting point (Tm) or an amorphous polyester polyol having no melting point (Tm), but is an amorphous polyester polyol. May be.

By including the structural unit derived from the component (a1) in the polymerized chain, the solidification time and viscosity of the reactive hot melt adhesive can be adjusted. The component (a1) may be a polycondensation reaction product of a polyhydric alcohol and a polycarboxylic acid. The component (a1) may be a linear polyester diol formed from a diol and a dicarboxylic acid, or a branched polyester triol formed from a triol and a dicarboxylic acid. The branched polyester triol can also be obtained by reacting a diol with a tricarboxylic acid.

Examples of the polyhydric alcohol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, butanediol isomers, pentandiol isomers, hexanediol isomers, and 2,2-. Diol-1,3-propanediol, 2-methylpropanediol, 2,4,4-trimethyl-1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol, 1,4-cyclohexane Aromatic or alicyclic diols such as diols, 1,4-cyclohexanedimethanol; aromatic diols such as 4,4'-dihydroxydiphenylpropane, bisphenol A, bisphenol F, pyrocatechol, resorcinol, hydroquinone (having an aromatic ring). Diol) and the like. One type of polyhydric alcohol may be used alone, or two or more types may be used in combination. Among these, an aliphatic diol is preferable, and an aliphatic diol having 2 to 6 carbon atoms is more preferable.

As the polycarboxylic acid, for example, the carbon atom of the carbonyl group (of the carboxylic acid) such as phthalic acid, isophthalic acid, terephthalic acid, 1,2,4-benzenetricarboxylic acid is directly bonded to the carbon atom constituting the aromatic ring. Polycarboxylic acid (hereinafter, may be referred to as "aromatic polycarboxylic acid"); maleic acid, fumaric acid, aconitic acid, 1,2,3-propanetricarboxylic acid, malonic acid, succinic acid. , Carbon of the carbonyl group (of the carboxylic acid), such as glutaric acid, adipic acid, pimelli acid, azelaic acid, sebacic acid, cyclohexane-1,2-dicarboxylic acid, 1,4-cyclohexanediene-1,2-dicarboxylic acid. Examples thereof include polycarboxylic acids in which atoms are directly bonded to carbon atoms constituting an aliphatic group (hereinafter, may be referred to as "aliphatic polycarboxylic acid" in some cases). The aromatic polycarboxylic acid may be a polycarboxylic acid in which the carbon atom of the carbonyl group (of the carboxylic acid) is directly bonded to the carbon atom constituting the benzene ring, and consists of phthalic acid, isophthalic acid, and terephthalic acid. It may be at least one selected from the group. One type of polycarboxylic acid may be used alone, or two or more types may be used in combination. The adjustment of C (A) / (C (A) + C (B)) in the formula (X) and C (A) / C (C) in the formula (Y) is to adjust the ratio of the aromatic polycarboxylic acid. Can be done by.

Instead of the polycarboxylic acid, a polycarboxylic acid derivative such as a carboxylic acid anhydride or a compound in which a part of the carboxyl group is esterified can also be used. Examples of the polycarboxylic acid derivative include phthalic anhydride, dimethyl terephthalate, dodecylmaleic acid, octadecenylmaleic acid and the like.

The component (a1) may be a polycondensation reaction product of a polyhydric alcohol and a polycarboxylic acid containing an aromatic polycarboxylic acid.

In the polycondensation reaction product of a polyhydric alcohol and a polycarboxylic acid, the content of the constituent unit derived from the aromatic polycarboxylic acid) is the total amount of the constituent units constituting the component (a1) (polycondensation reaction product). As a reference, it may be, for example, 10 to 60 mol%. The content of the structural unit derived from the compound having an aromatic ring may be 15 mol% or more or 20 mol% or more, 55 mol% or less, or 55 mol% or less, based on the total amount of the structural units constituting the component (a1). It may be 50 mol% or less.

A polycarboxylic acid in which the component (a1) contains a polyvalent alcohol and an aromatic polycarboxylic acid (a polycarboxylic acid having an aromatic ring, preferably at least one selected from the group consisting of phthalic acid, isophthalic acid, and terephthalic acid). In the case of a polycondensation reaction product with, the content of the structural unit derived from the aromatic polycarboxylic acid is 20 to 100 mol% and 25 to 100 mol% based on the total amount of the structural unit derived from the polycarboxylic acid. , Or 30-100 mol%.

The number average molecular weight (Mn) of the component (a1) may be 500 to 12000 from the viewpoint of adhesive strength. The number average molecular weight (Mn) of the component (a1) may be 1000 or more, 1500 or more, or 1800 or more, or 11000 or less, 10000 or less, or 9000 or less. In addition, in this specification, Mn is a value measured by gel permeation chromatography (GPC) and converted into standard polystyrene.

In the present specification, the measurement of GPC for obtaining the number average molecular weight (Mn) can be performed under the following conditions, for example.
Columns: "Gelpack GLA130-S", "Gelpack GLA150-S" and "Gelpack GLA160-S" (manufactured by Hitachi Kasei Co., Ltd., packed column for HPLC)
Eluent: tetrahydrofuran Flow rate: 1.0 mL / min Column temperature: 40 ° C
Detector: RI

The content of the component (a1) (constituent unit derived from the component (a1)) is 50% by mass or more, 55% by mass or more, based on the total amount of the component (a) (constituent unit derived from the component (a)). It may be 60% by mass or more, 65% by mass or more, 70% by mass or more, or 75% by mass or more. When the content of the component (a1) is 50% by mass or more based on the total amount of the component (a), the obtained urethane prepolymer (reactive hot melt adhesive) tends to have excellent initial adhesive strength. On the other hand, the upper limit of the content of the component (a1) (constituent unit derived from the component (a1)) is based on the total amount of the component (a) (constituent unit derived from the component (a)) from the viewpoint of workability. It may be 100% by mass or less, 95% by mass or less, or 90% by mass or less.

Since the content of the component (a1) (constituent unit derived from the component (a1)) is superior in adhesive strength and elasticity, the total amount of the component (a) (constituent unit derived from the component (a)) is used. When it is 100 mol%, it may be 50 mol% or more, 55 mol% or more, 60 mol% or more, 65 mol% or more, 70 mol% or more, or 75 mol% or more, and 100 mol% or less, 95 mol% or more. It may be less than or equal to 90 mol% or less.

The component (a2) is a polyol other than the polyester polyol having an aromatic ring. Examples of the component (a2) include polyester polyols having no aromatic ring, polyether polyols, polyether ester polyols, polyurethane polyols, polycarbonate polyols, and polyolefin polyols.

The component (a) may contain a polyether polyol having an aromatic ring as the component (a2) from the viewpoint of improving the initial adhesive strength. The polyether polyol having an aromatic ring may be an amorphous polyether polyol. The polyether polyol having an aromatic ring may be a polyether polyol having a bisphenol skeleton, and the bisphenol skeleton may be a bisphenol A skeleton or a bisphenol F skeleton. The polyether polyol having a bisphenol A skeleton or a bisphenol F skeleton may be a bisphenol A or bisphenol F modified with an alkylene oxide, and more specifically, a bisphenol A or a propylene oxide modified. May be good. The component (a) tends to be more excellent in adhesive strength by containing the polyether polyol having such a bisphenol skeleton as the component (a2).

The content of the polyether polyol having a bisphenol skeleton may be 0 to 10% by mass, based on the total amount of the component (a) (the structural unit derived from the component (a)), and may be 1% by mass or more and 2% by mass. It may be more than or equal to 3% by mass or more, and may be 8% by mass or less, 6% by mass or less, or 5% by mass or less.

The content of the polyether polyol having an aromatic ring having a bisphenol skeleton may be 0 to 10 mol% when the total amount of the component (a) (the structural unit derived from the component (a)) is 100 mol%. It may be 1 mol% or more, 2 mol% or more, or 3 mol% or more, and may be 8 mol% or less, 6 mol% or less, or 5 mol% or less.

The number average molecular weight (Mn) of the component (a2) may be 100 to 10000 from the viewpoint of reducing the viscosity of the urethane prepolymer. The number average molecular weight (Mn) of the component (a2) may be 400 or more or 1000 or more, and may be 8000 or less or 5000 or less. In addition, in this specification, Mn is a value measured by gel permeation chromatography (GPC) and converted into standard polystyrene.

The content of the component (a2) (constituent unit derived from the component (a2)) may be 0 to 50% by mass based on the total amount of the component (a) (constituent unit derived from the component (a)). It may be 5% by mass or more or 10% by mass or more, and may be 45% by mass or less, 40% by mass or less, 35% by mass or less, 30% by mass or less, or 25% by mass or less.

The content of the component (a2) (constituent unit derived from the component (a2)) is 0 to 50 mol% when the total amount of the component (a) (constituent unit derived from the component (a)) is 100 mol%. It may be 5 mol% or more, 10 mol% or more, 45 mol% or less, 40 mol% or less, 35 mol% or less, 30 mol% or less, or 25 mol% or less.

(B) Component: Polyisocyanate Polyisocyanate can be used without particular limitation as long as it is a compound having two or more isocyanate groups. The polyisocyanate may be a compound having two isocyanate groups (diisocyanate). Examples of the polyisocyanate include aromatic isocyanates such as diphenylmethane diisocyanate (4,4'-diphenylmethane diisocyanate), dimethyldiphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, and p-phenylenediisocyanate; and dicyclohexylmethane diisocyanate and isophorone diisocyanate. Alicyclic isocyanate; examples thereof include aliphatic isocyanates such as hexamethylene diisocyanate. From the viewpoint of reactivity and adhesive strength, the polyisocyanate preferably contains an aromatic diisocyanate, and more preferably contains a diphenylmethane diisocyanate. One type of polyisocyanate may be used alone, or two or more types may be used in combination.

The urethane prepolymer can be synthesized by reacting the component (a) containing the component (a1) at a predetermined content with the component (b). The urethane prepolymer is bonded to a polymer chain containing a structural unit derived from the component (a1) and a structural unit derived from the component (b) at the end of the polymer chain. It has an isocyanate group. When synthesizing such a urethane prepolymer, the equivalent ratio of the isocyanate group (NCO) of the component (b) to the hydroxy group (OH) of the component (a) (the isocyanate group (NCO) equivalent of the component (b) / (a) ) Component hydroxy group (OH) equivalent, NCO / OH) may be 1.1 or more, and may be 1.1 to 2.1. When NCO / OH is 1.1 or more, the urethane prepolymer has an isocyanate group bonded to the end of the polymerized chain, and it is possible to suppress an increase in the viscosity of the urethane prepolymer, further improving workability. There is a tendency. When the NCO / OH is 2.1 or less, foaming is less likely to occur during the moisture curing reaction of the reactive hot melt adhesive, and it tends to be easy to suppress a decrease in adhesive strength.

The temperature and time for reacting the component (a) and the component (b) when synthesizing the urethane prepolymer are not particularly limited, but may be, for example, 85 to 120 ° C. and 0.1 minutes to 48 hours.

The urethane prepolymer may satisfy both the following condition (i) and condition (ii). Such a reactive hot melt adhesive containing a urethane prepolymer is excellent in initial adhesive strength and excellent in workability.
Condition (i): The melt viscosity at 120 ° C. is 1 to 30 Pa · s.
Condition (ii): The melt viscosity at 80 ° C. is 100 Pa · s or more.

Regarding condition (i), the melt viscosity of the urethane prepolymer at 120 ° C. is 1 to 30 Pa · s. When the melt viscosity of the urethane prepolymer at 120 ° C. is 1 to 30 Pa · s, the viscosity is sufficiently low, so that workability (dischargeability in coating, spinnability, etc.) is excellent. The melt viscosity at 120 ° C. may be 3 Pa · s or more, 5 Pa · s or more, 7 Pa · s or more, or 10 Pa · s or more, 28 Pa · s or less, 25 Pa · s or less, 20 Pa · s or less, or 15 Pa · s or less. -It may be s or less.

Regarding the condition (ii), the melt viscosity of the urethane prepolymer at 80 ° C. is 100 Pa · s or more. When the melt viscosity of the urethane prepolymer at 80 ° C. is 100 Pa · s or more, the viscosity required for the adhesive force is developed at an early stage, and as a result, the initial adhesive force is excellent. The melt viscosity at 80 ° C. may be 110 Pa · s or more, 120 Pa · s or more, 130 Pa · s or more, or 140 Pa · s or more. The upper limit of the melt viscosity at 80 ° C. is not particularly limited, but may be, for example, 1000 Pa · s or less, 800 Pa · s or less, 600 Pa · s or less, 500 Pa · s or less, or 400 Pa · s or less. The melt viscosity at 120 ° C. is measured by a rotary rheometer device.

The melt viscosity at 120 ° C. and the melt viscosity at 80 ° C. of the urethane prepolymer are measured by a rotary rheometer device, and are measured by, for example, the following methods. A separate sample for measuring the melt viscosity at 120 ° C. and a sample for measuring the melt viscosity at 80 ° C. are prepared and measured. The measuring device and measuring conditions are as follows.
・ Rotary rheometer device: DHR-2 (TA Instruments Japan Co., Ltd.)
・ Geometry: Φ20mm (2 °) cone plate ・ GAP: 57μm
・ Shear velocity: 33 (1 / s)
-Melting viscosity at 120 ° C: Measured value measured after incubating urethane prepolymer (reactive hot melt adhesive) at 120 ° C for 5 minutes-Melting viscosity at 80 ° C: Urethane prepolymer (reactive hot melt adhesive) Measured after keeping the temperature at 80 ° C for 5 minutes

The melt viscosity of the urethane prepolymer can be adjusted mainly by changing the type, content, etc. of the structural unit derived from the polyol. The type, content, and the like of the structural unit derived from the polyol are not particularly limited as long as the urethane prepolymer satisfies the condition (i) and the condition (ii). According to the study by the present inventors, when the structural unit derived from the polyol contains the structural unit derived from the polyester polyol having an aromatic ring, the urethane prepolymer easily satisfies the condition (i) and the condition (ii). It has been found that the urethane prepolymer which tends to satisfy the condition (i) and the condition (ii) tends to satisfy the formulas (X) and (Y) easily.

The reactive hot melt adhesive may further contain a catalyst from the viewpoint of accelerating the curing of the urethane prepolymer and developing higher adhesive strength. Examples of the catalyst include dibutyltin dilaurate, dibutylthione octate, dimethylcyclohexylamine, dimethylbenzylamine, trioctylamine, dimorpholinodiethyl ether (bis (2-morpholinoethyl) ether) and the like. The content of the catalyst may be 0.001 to 0.5% by mass based on the total amount of the reactive hot melt adhesive.

The reactive hot melt adhesive may further contain a thermoplastic polymer from the viewpoint of increasing the rubber elasticity of the adhesive layer to be formed and further improving the impact resistance. Examples of the thermoplastic polymer include polyurethane, ethylene-based copolymer, propylene-based copolymer, vinyl chloride-based copolymer, acrylic copolymer, and styrene-conjugated diene block copolymer. The content of the thermoplastic polymer may be 0.1 to 50% by mass based on the total amount of the reactive hot melt adhesive.

The reactive hot melt adhesive may further contain a tackifier resin from the viewpoint of imparting a stronger adhesive force to the formed adhesive layer. Examples of the tackifying resin include rosin resin, rosin ester resin, hydrogenated rosin ester resin, terpene resin, terpene phenol resin, hydrogenated terpene resin, petroleum resin, hydrogenated petroleum resin, kumaron resin, ketone resin, and styrene resin. Examples thereof include modified styrene resin, xylene resin, and epoxy resin. The content of the tackifier resin may be 0.1 to 50% by mass based on the total amount of the reactive hot melt adhesive.

The reactive hot melt adhesive may further contain other components, if necessary. Examples of other components include antioxidants, pigments, ultraviolet absorbers, surfactants, flame retardants, fillers, photocolorants, thermal color inhibitors, fragrances, imaging agents, thermal cross-linking agents and the like. The content of the other components may be 0.001 to 10% by mass based on the total amount of the reactive hot melt adhesive.

The reactive hot melt adhesive may consist of urethane prepolymer alone or may contain other components in addition to urethane prepolymer. When the reactive hot melt adhesive consists of urethane prepolymer alone, if the urethane prepolymer satisfies both the conditions (i) and (ii), the reactive hot melt adhesive also satisfies the conditions (i) and condition (ii). Satisfy both. Further, even when the reactive hot melt adhesive contains other components in addition to the urethane prepolymer, by containing the urethane prepolymer that satisfies both the condition (i) and the condition (ii). , A reactive hot-melt adhesive having excellent initial adhesive strength and excellent workability, and the reactive hot-melt adhesive can satisfy both the condition (i) and the condition (ii). Further, even if the reactive hot melt adhesive containing an arbitrary urethane prepolymer and other components satisfies both the condition (i) and the condition (ii), the initial adhesive strength is excellent and the workability is excellent. Can be excellent.

That is, the reactive hot melt adhesive may satisfy both the following condition (i) and condition (ii). The reactive hot melt adhesive may contain a urethane prepolymer.
Condition (i): The melt viscosity at 120 ° C. is 1 to 30 Pa · s.
Condition (ii): The melt viscosity at 80 ° C. is 100 Pa · s or more.

The preferred ranges of the melt viscosity at 120 ° C. and the melt viscosity at 80 ° C. of the reactive hot melt adhesive are the same as the preferable ranges of the melt viscosity at 120 ° C. and the melt viscosity at 80 ° C. of the above urethane prepolymer. Further, the measurement conditions for the melt viscosity of the reactive hot melt adhesive are the same as the measurement conditions for the melt viscosity of the urethane prepolymer. Therefore, a duplicate description will be omitted here.

The content of the urethane prepolymer based on the total amount of the reactive hot melt adhesive is 80% by mass or more, 85% by mass or more, 90% by mass or more, 92% by mass or more, 95% by mass or more, or 97% by mass. % Or more, and may be 100% by mass. By adjusting the melt viscosity of the urethane prepolymer by adjusting the content of the urethane prepolymer in such a range, the melt viscosity of the reactive hot melt adhesive satisfies both the condition (i) and the condition (ii). It becomes easy to adjust to. Further, when the melt viscosity of the urethane prepolymer satisfies both the condition (i) and the condition (ii), the melt viscosity of the reactive hot melt adhesive also easily satisfies both the condition (i) and the condition (ii). ..

In the reactive hot melt adhesive, for example, the temperature is 23 ° C. and 50% because the isocyanate group of the urethane prepolymer contained in the reactive hot melt adhesive reacts with the moisture in the air or the moisture on the surface of the adherend. It can be cured by leaving (curing) at RH (relative humidity) for 24 hours. In this way, a cured product of the reactive hot melt adhesive can be obtained.

The reactive hot melt adhesive can be used, for example, by melting at 60 to 130 ° C. and then applying it to an adherend. The coating method is not particularly limited, and examples thereof include a method using a coating device such as a bar coater, a die coater, a roll coater, and a spray. When applying to a narrow part such as a small part, a dispenser is suitable. The application pattern of the reactive hot melt adhesive can be appropriately set, and examples thereof include a dot-like, linear, zigzag-like, planar, and curved application patterns.

The reactive hot melt adhesive can adhere various adherends via a cured product (adhesive layer) of the reactive hot melt adhesive. Examples of the adherend include metal base materials such as SUS and aluminum, and non-metal base materials such as cloth, paper, polycarbonate, polyamide, polyetherimide, glass, and carbon fiber. Among these, the adherend may be, for example, cloth or paper. Reactive hot melt adhesives can be suitably used to bond a plurality of adherends selected from cloth and paper to each other. In this case, the combination of adherends can be cloth and cloth, paper and paper, or cloth and paper. The reactive hot melt adhesive can be suitably used for clothing such as clothing (apparel products), supporters, bags, wallets, interiors, various covers, cases, wearable devices, etc., and can be particularly preferably used for clothing. ..

The reactive hot melt adhesive may be formed in the form of a film and used as an adhesive film. Such an adhesive film is obtained by applying, for example, a reactive hot melt adhesive onto a support film such as a PET (polyethylene terephthalate) film to form an adhesive layer to obtain an adhesive film. Can be done. The thickness of the adhesive layer (adhesive film) may be 10 μm or more, 20 μm or more, or 30 μm or more, and may be 300 μm or less, 250 μm or less, or 200 μm or less. The thicker the film, the more the adhesive strength tends to be secured, and the thinner the film, the easier it is to secure the elasticity.

[Adhesive and its manufacturing method]
The adhesive body of one embodiment includes a first adherend, a second adherend, and an adhesive layer that adheres the first adherend and the second adherend to each other. The adhesive layer contains a cured product of the above reactive hot melt adhesive. Examples of the article provided with the adhesive include clothing (particularly, non-sewn clothing), semiconductor devices, electronic devices, and the like.

As the first adherend and the second adherend, the same ones as those exemplified in the above-mentioned adherend can be exemplified. The first adherend and the second adherend may be, for example, cloth or paper, and the combination of the first adherend and the second adherend may be cloth and cloth, paper and paper. Alternatively, it may be cloth and paper. When the article provided with the adhesive is clothing, the first adherend and the second adherend are cloth.

The adhesive of the present embodiment has a step of melting the above-mentioned reactive hot melt adhesive and applying it to a first adherend to form an adhesive layer, and a second adherend on the adhesive layer. Can be produced by a method including a step of obtaining a laminate by crimping a second adherend and a step of obtaining an adhesive by curing the adhesive layer.

The temperature at which the reactive hot melt adhesive is melted may be, for example, 60 to 130 ° C. Examples of the method of applying the reactive hot melt adhesive to the first adherend include a method of using a coating device such as a die coater, a roll coater, or a spray. When applying to a narrow part such as a small part, a dispenser is suitable.

Examples of the method of crimping the second adherend include a method of crimping using a pressure roll or the like.

The reactive hot melt adhesive in the adhesive layer can be cured by, for example, leaving (curing) at a temperature of 23 ° C. and 50% RH (relative humidity) for 24 hours. Thereby, the adhesive layer may contain a cured product of the reactive hot melt adhesive.

FIG. 1 is a schematic view showing a method for manufacturing an adhesive according to an embodiment, and FIGS. 1 (a), (b), (c), and (d) are schematic views showing each step. In the following, with reference to FIG. 1, a method for manufacturing an adhesive using a stretchable cloth, which is a cloth, as the first adherend and the second adherend will be described.

First, the elastic fabric 1 is installed along the jig 10 (see (a) in FIG. 1). Next, the reactive hot melt adhesive of the present embodiment is applied to a predetermined portion of the stretchable fabric 1 to form the adhesive layer 4 (see FIG. 1 (b)). The material and shape of the jig 10 are not particularly limited, and can be appropriately selected depending on the intended purpose. The application of the reactive hot melt adhesive may be carried out using, for example, a dispenser. Next, the elastic fabric 2 is arranged on the adhesive layer 4, and the elastic fabric 1 and the elastic fabric 2 are passed through the adhesive layer 4 while applying pressure from above the elastic fabric 2 by a roll or the like. To obtain a laminated body 20 (see (c) and (d) of FIG. 1). After that, by leaving (curing) the laminated body 20, the reactive hot melt adhesive in the adhesive layer 4 is moisture-cured, and an adhesive body in which the elastic fabrics are adhered to each other can be obtained. The adhesive layer 4 in the adhesive contains a cured product of the reactive hot melt adhesive.

In FIG. 1B, an adhesive film made of a reactive hot melt adhesive previously formed on a releasable substrate is transferred onto the elastic fabric 1 to form an adhesive layer 4. You may. Alternatively, an adhesive may be provided on the stretchable fabric 2 and bonded to the stretchable fabric 1.

[clothing]
The garment of one embodiment comprises the above-mentioned adhesive. In this case, the first adherend and the second adherend may be cloth. The garment can be non-sewn garment.

[analysis]
The urethane prepolymer contained in the reactive hot melt adhesive of the present embodiment can identify the constituent components of the urethane prepolymer by, for example, solution NMR measurement. When the reactive hot melt adhesive of the present embodiment contains a component other than the urethane prepolymer, for example, the urethane prepolymer is isolated by preparative liquid chromatography (known means such as GPC), and the solvent is retained. The components of the urethane prepolymer can be identified by performing solution NMR measurement after the removal. Further, by using the same method, components other than the urethane prepolymer contained in the reactive hot melt adhesive can be specified.

In the cured product of the reactive hot melt adhesive of the present embodiment, for example, only the uncured component is extracted using a solvent in which the uncured component of the cured product such as tetrahydrofuran is dissolved and the cured product itself is difficult to dissolve. By decomposing the undissolved component (cured product component) of the residue with pyridine and breaking the urethane bond, the constituent components of the urethane prepolymer before curing can be specified.

Hereinafter, the present disclosure will be described in more detail with reference to examples. However, the present disclosure is not limited to these examples.

(Manufacturing Examples 1 to 5)
<Preparation of urethane prepolymer (reactive hot melt adhesive)>
The urethane prepolymers A to E of Production Examples 1 to 5 were prepared using the polyols and polyisocyanates of the types and parts by mass shown in Table 1. More specifically, Table 1 shows the equivalent ratio ((NCO) equivalent / (OH) equivalent) of the isocyanate group of the polyisocyanate to the hydroxy group of the polyol with respect to the polyol previously dehydrated by the vacuum dryer. The mixture was added to the reaction vessel so as to have the values shown, and mixed at 110 ° C. for 1 hour until uniform. Then, the urethane prepolymer was obtained by further defoaming and stirring at 110 ° C. for 1 hour under reduced pressure. As shown in Table 1, since the (NCO) equivalent / (OH) equivalent is larger than 1, the obtained urethane prepolymer has a polymer chain containing a structural unit derived from a polyol and a structural unit derived from a polyisocyanate. It is presumed to have an isocyanate group bonded to the end of the polymerized chain. In the following, the obtained urethane prepolymer was used as it was as a reactive hot melt adhesive.

The details of each component shown in Table 1 are as follows.
(A) Polyester (a1) Polyester polyol having an aromatic ring (a1) -1: Non-polyester having an aromatic ring containing dicarboxylic acid (adipic acid and isophthalic acid) and diol (ethylene glycol and neopentyl glycol) as main components. Crystalline polyester polyol (number of hydroxyl groups: 2, number average molecular weight: 2000, content of structural units derived from a compound having an aromatic ring: 25 mol% (based on the total amount of structural units constituting the amorphous polyester polyol), 50 mol % (Based on the total amount of constituent units derived from dicarboxylic acid), melting point (Tm): none)
(A1) -2: Acrystalline polyester polyol having an aromatic ring containing a dicarboxylic acid (phthalic anhydride) and a diol (ethylene glycol and diethylene glycol) as main components (number of hydroxyl groups: 2, number average molecular weight: 2000, aromatic) Content of constituent units derived from a ring-bearing compound: 50 mol% (based on the total amount of constituent units constituting the amorphous polyester polyol), 100 mol% (based on the total amount of constituent units derived from dicarboxylic acid), melting point (Tm) ):none)

Polyesters other than (a2) and (a1) (a2) -1: Acyclic having no aromatic ring and containing dicarboxylic acid (adipic acid) and diol (1,4-butanediol and neopentyl glycol) as main components. Polyester polyol (number of hydroxyl groups: 2, number average molecular weight: 5000, melting point (Tm): none)
(A2) -2: Crystalline polyester polyol having no aromatic ring and containing dicarboxylic acid (adipic acid) and diol (ethylene glycol and 1,4-butanediol) as main components (number of hydroxyl groups: 2, number average molecular weight) : 2038, melting point (Tm): 20 ° C)
(A2) -3: Achromatic polyether polyol having an aromatic ring (bisphenol A / PO system) (manufactured by ADEKA Corporation, trade name: BPX-11, number of hydroxyl groups: 2, melting point (Tm): none)

(B) Polyisocyanate (b) -1: Diphenylmethane diisocyanate (manufactured by Tosoh Corporation, trade name: millionate MT, number of isocyanate groups: 2)

< ¹³ C-NMR analysis>
¹³ C-NMR analysis was performed on urethane prepolymers A to E. ¹³ ^{C-NMR analysis was carried out using AVANCE NEO (probe: CryoProbe TM} ) manufactured by Bruker Japan Co., Ltd. as a nuclear magnetic resonance spectrometer (NMR) under the following measurement conditions.

(Measurement condition)
・¹³ C-NMR quantitative spectrum: inverse gate decoupling method ・ Resonance frequency: 100 MHz
・ Waiting time (d1): 5 seconds ・ Solvent: Deuterated chloroform (CDCl ₃ )
-Sample concentration: 100 mg / 0.6 ml-CDCl ₃ and 10 mgCr (acac) ₃ as a relaxation reagent at the same time-Chemical shift standard: Tetramethylsilane (TMS) peak set to 0.00 ppm-Measurement temperature: 23 ° C
・ Cumulative number: 400 times

^{FIG. 2 is a 13} C-NMR spectrum of the urethane prepolymer B of Production Example 2 in the range of 150 to 180 ppm. ^{In the 13} C-NMR spectrum of FIG. 2, when the integrated value (C (B)) of the peak observed in the range of 171 to 176 ppm is 10.000, the integrated value of the peak observed in the range of 163 to 170 ppm. The integral values (C (C)) of (C (A)) and the peaks observed in the range of 150 to 155 ppm were 33.039 and 5.081, respectively. ^{FIG. 3 is a 13} C-NMR spectrum of the urethane prepolymer E of Production Example 5 in the range of 150 to 180 ppm. ^{In the 13} C-NMR spectrum of FIG. 3, when the integrated value (C (B)) of the peak observed in the range of 171 to 176 ppm is 10.000, the integrated value of the peak observed in the range of 163 to 170 ppm. The integral values (C (C)) of (C (A)) and the peaks observed in the range of 150 to 155 ppm were 4.805 and 1.564, respectively. The results are shown in Table 1. Based on these numerical values and the like, C (A) / (C (A) + C (B)) and C (A) / C (C) were calculated. The results are shown in Table 1.

(Examples 1 to 3 and Comparative Examples 1 and 2)
<Evaluation of reactive hot melt adhesive>
-Initial Adhesive Strength and Final Adhesive Strength The reactive hot-melt adhesives (urethane prepolymers A to E) of Examples 1 to 3 and Comparative Examples 1 and 2 are melted at 120 ° C. and stretchable fabrics (spandex, Toray Op). An adhesive layer was formed by applying it on Lycra (registered trademark) manufactured by Rontex Co., Ltd. and applying it to a thickness of 80 μm with a bar coater. The same elastic fabric was placed on the formed adhesive layer and crimped at 120 ° C. to obtain a crimped body. The adhesive strength of the crimped body after 5 minutes from the time of crimping was measured using a force gauge (manufactured by Imada Co., Ltd., DS250N), and this was used as the initial adhesive strength of the reactive hot melt adhesive. Next, the pressure-bonded body was cured in a constant temperature bath at 23 ° C. and 50% RH for 1 day, and the adhesive layer was cured to prepare an adhesive body. The adhesive strength of the adhesive is measured by a T-type peel strength test using a tensile tester (manufactured by Shimadzu Corporation, EZ-Test EZ-SX) at a measurement temperature of 25 ° C and a tensile speed of 100 mm / min. This was used as the final adhesive strength. The results are shown in Table 1.

-Break elongation The reactive hot melt adhesives (urethane prepolymers A to E) of Examples 1 to 3 and Comparative Examples 1 and 2 were melted at 100 ° C. to form a film having a thickness of 100 μm, and then the formed film. Was cured by allowing it to stand in a constant temperature and humidity chamber having a temperature of 23 ° C. and a humidity of 50% for 2 days. The cured film is punched out with a No. 1 dumbbell to prepare a test piece, and the breaking elongation (%) of the test piece is based on JIS K-6251 using Autograph AGS-X (manufactured by Shimadzu Corporation). Was measured. The results are shown in Table 1.

^{When 13} C-NMR analysis was performed on urethane prepolymers A to E, C (A) / (C (A) + C (B)) of urethane prepolymers A to C was 0.36 or more, and further. C (A) / C (C) was 3.6 or more. The reactive hot-melt adhesives of Examples 1 to 3 using such urethane prepolymers are compared with the reactive hot-melt adhesives of Comparative Examples 1 and 2 using urethane prepolymers that do not meet the predetermined requirements. , It was found that the initial adhesive strength and the final adhesive strength tended to be excellent. It was also found that the reactive hot melt adhesives of Examples 1 to 3 tend to have a sufficiently high level of elongation at break. From these results, it was confirmed that the reactive hot melt adhesive of the present disclosure has excellent adhesive strength (both initial adhesive strength and final adhesive strength) and excellent elasticity.

1,2 ... Elastic fabric, 4 ... Adhesive layer, 10 ... Jig, 20 ... Laminate.

Claims

Contains urethane prepolymer,
In the urethane prepolymer, the integral value of the peak observed in the range of 163 to 170 ppm is C (A), and the integral value of the peak observed in the range of 171 to 176 ppm is C (B) in the 13 C-NMR analysis. When, the C (A) and the C (B) satisfy the following formula (X).
Reactive hot melt adhesive.
0.36 ≤ C (A) / (C (A) + C (B)) (X)
In the urethane prepolymer, the C (A) and the C (C) are expressed by the following formulas, where C (C) is the integral value of the peaks observed in the range of 150 to 155 ppm in 13 C-NMR analysis. Satisfy Y)
The reactive hot melt adhesive according to claim 1.
3.6 ≤ C (A) / C (C) (Y)
The urethane prepolymer has a structural unit derived from a polyol and has
The structural unit derived from the polyol includes a structural unit derived from a polyester polyol having an aromatic ring.
The reactive hot melt adhesive according to claim 1 or 2.
Used to attach multiple adherends selected from cloth and paper to each other,
The reactive hot melt adhesive according to any one of claims 1 to 3.
The first adherend and
The second adherend and
An adhesive layer that adheres the first adherend and the second adherend to each other,
With
The adhesive layer contains a cured product of the reactive hot melt adhesive according to any one of claims 1 to 3.
Adhesive body.
The adhesive according to claim 5 is provided.
The first adherend and the second adherend are cloths.
clothing.
A step of forming an adhesive layer by melting the reactive hot melt adhesive according to any one of claims 1 to 3 and applying it to a first adherend.
A step of arranging a second adherend on the adhesive layer and crimping the second adherend to obtain a laminate.
A step of obtaining an adhesive by curing the adhesive layer in the laminate, and
To prepare
How to make an adhesive.