Reactive hot melt adhesive, adhesive body and method for producing the same, and clothing

Abstract

The present invention discloses a reactive hot melt adhesive containing a polyurethane prepolymer. 13 In C-NMR analysis, when the integrated value of the peak observed in the range of 163 to 170 ppm is defined as C(A), and the integrated value of the peak observed in the range of 171 to 176 ppm is defined as C(B), C(A) and C(B) satisfy the following formula (X). 0.36≤C(A) / (C(A)+C(B))(X)

Description

Technical Field

[0001] The invention relates to a reactive hot-melt adhesive, an adhesive body, a method for making the same and clothing. Background Art

[0002] Hot melt adhesives are solvent-free adhesives, so they have less burden on the environment and the human body, and they can be bonded in a short time, so they are suitable for improving production efficiency. Hot melt adhesives can be roughly divided into two types, one with thermoplastic resin as the main component and the other with reactive resin as the main component. As reactive resins, polyurethane prepolymers with isocyanate groups at the ends are mainly used.

[0003] After coating, the reactive hot melt adhesive with polyurethane prepolymer as the main component will show a certain degree of adhesiveness in a short time due to the cooling and solidification of the adhesive itself. After that, the terminal isocyanate group of the polyurethane prepolymer will react with moisture (water in the air or on the surface of the adherend) to increase the molecular weight and cross-link, thereby showing heat resistance. This adhesive is called a moisture-curing reactive hot melt adhesive. The reactive hot melt adhesive with polyurethane prepolymer as the main component also shows good adhesiveness when heated.

[0004] For example, Patent Document 1 discloses a reactive hot-melt adhesive, which is composed of a polyurethane prepolymer, wherein the polyurethane prepolymer is formed by a polyisocyanate (a) and a polyol (b), wherein the polyol (b) is composed of a polyether polyol (b1) containing an aromatic ring and / or a polyester polyol (b2) containing an aromatic ring and an aliphatic polyester polyol (b3).

[0005] Previous technical literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2008-063568 Summary of the invention

[0008] Technical issues to be solved by the invention

[0009] In recent years, various reactive hot melt adhesives have been used as wearable terminals and the like have become more diverse. In reactive hot melt adhesives, there is a trade-off between adhesive strength and elasticity, and it is very important to make them compatible. However, the compatibility between adhesive strength and elasticity of conventional reactive hot melt adhesives is not yet sufficient, and there is still room for further improvement.

[0010] Therefore, an object of the present invention is to provide a reactive hot-melt adhesive having excellent adhesive strength and excellent stretchability.

[0011] Means for solving technical problems

[0012] In order to solve the above problems, the present inventors conducted a study on polyurethane prepolymers. 13 C-NMR analysis was performed and the constituent units contained in the polyurethane prepolymer were studied. As a result, it was found that the polyurethane prepolymer having an integrated value of the peak observed within a specified range of a specified ratio tends to have excellent adhesion and excellent stretchability, thus completing the invention of the present disclosure.

[0013] One aspect of the present invention relates to a reactive hot melt adhesive. The reactive hot melt adhesive contains a polyurethane prepolymer. The polyurethane prepolymer is 13 In C-NMR analysis, when the integrated value of the peak observed in the range of 163 to 170 ppm is defined as C(A), and the integrated value of the peak observed in the range of 171 to 176 ppm is defined as C(B), C(A) and C(B) satisfy the following formula (X). This reactive hot melt adhesive is an adhesive having excellent adhesive strength and excellent elasticity.

[0014] 0.36≤C(A) / (C(A)+C(B))(X)

[0015] In this manual 13 C-NMR analysis was performed using AVANCE NEO manufactured by Bruker Japan KK (probe: CryoProbe TM ) as a nuclear magnetic resonance spectrometer (NMR), and the analysis was carried out under the following measurement conditions.

[0016] (Measurement conditions)

[0017] · 13 C-NMR quantitative spectroscopy: inverse gate decoupling method

[0018] Resonance frequency: 100MHz

[0019] Waiting time (d1): 5 seconds

[0020] Solvent: heavy chloroform (CDCl3)

[0021] Sample concentration: 100mg / 0.6ml-CDCl3, also contains 10mgCr(acac)3 as a relaxation reagent

[0022] Chemical shift standard: Set the peak of tetramethylsilane (TMS) to 0.00 ppm

[0023] ·Measurement temperature: 23℃

[0024] Cumulative times: 400 times

[0025] In addition, regarding the method of obtaining the integral value, for example, it is also possible to measure the integral value for each peak observed in the range of 163 to 170 ppm and set the sum of their integral values ​​as C(A). However, since it is easy to obtain the integral value and it is possible to reduce arbitrariness, it is possible to measure the integral value of the entire range of 163 to 170 ppm and set the integral value as C(A) (for example, refer to Figure 2 , Figure 3 ). The same is true for 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 can be set to the integral value of all peaks in the range of 163 to 170 ppm, the integral value of all peaks in the range of 171 to 176 ppm, and the integral value of all peaks in the range of 150 to 155 ppm, respectively.

[0026] The polyurethane prepolymer may be, for example, a polyurethane prepolymer having an isocyanate group. The polyurethane prepolymer having an isocyanate group generally has a polymer chain and an isocyanate group, wherein the polymer chain contains a structural unit derived from a polyol and a structural unit derived from a polyisocyanate. The isocyanate group may be bonded to the end of the polymer chain. 13In the C-NMR analysis, the peak observed in the range of 160 to 180 ppm is mainly the peak of the carbon atom of the carbonyl group of the ester bond of the structural unit derived from the polyester polyol in the structural unit derived from the polyol constituting the polyurethane prepolymer. The peak observed in the range of 163 to 170 ppm is the peak of the carbon atom of the carbonyl group directly bonded to the carbon atom constituting the aromatic ring among the carbon atom of the carbonyl group of the ester bond of the polyester polyol (hereinafter, this carbon atom may be referred to as "carbon atom (A)"). The peak observed in the range of 171 to 176 ppm is the peak of the carbon atom of the carbonyl group directly bonded to the carbon atom constituting the aliphatic group among the carbon atom of the carbonyl group of the ester bond of the polyester polyol (hereinafter, this carbon atom may be referred to as "carbon atom (B)"). The carbon atom (A) may be, for example, a carbon atom represented by the following formula (1), and the carbon atom (B) may be, for example, a carbon atom represented by the following formula (2). The integral value of the peak of 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)).) can be the sum of the integral value of the peak attributed to the carbon atom (A) (corresponding to the above C(A).) and the integral value of the peak attributed to the carbon atom (B) (corresponding to the above C(B).). Therefore, C(A) / (C(A)+C(B)) in the above formula (X) refers to 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) (total amount of carbon atoms (A) / total amount of carbon atoms (A) and the sum of the total amount of carbon atoms (B)). It can be said that the larger C(A) / (C(A)+C(B)), the greater the proportion of carbon atoms (A) in the unit derived from the polyester polyol constituting the polyurethane prepolymer (that is, the greater the proportion of aromatic rings contained in the polyester polyol).

[0027]

[0028] Polyester polyols can be condensation products of polyols and polycarboxylic acids. In this case, the carbon atom (A) and the carbon atom (B) mentioned above are carbon atoms derived from polycarboxylic acids. Carbon atom (A) is a carbon atom of a carbonyl group (of a carboxylic acid) that is directly bonded to a carbon atom constituting an aromatic ring among carbon atoms derived from polycarboxylic acids. 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 acids. C(A) / (C(A)+C(B)) in formula (X) tends to: It can be adjusted mainly by changing the type and content of the polycarboxylic acids constituting the structural units derived from polyester polyols, and the type and content of the polyester polyols derived from the polycarboxylic acids.

[0029] Polyurethane prepolymer 13In C-NMR analysis, when the integrated value of the peak observed in the range of 150 to 155 ppm is defined as C(C), C(A) and C(C) can satisfy the following formula (Y).

[0030] 3.6≤C(A) / C(C)(Y)

[0031] exist 13 In C-NMR analysis, the peak observed in the range of 160 to 180 ppm is mainly a peak attributable to the carbon atom of the carbonyl group of the polyurethane bond formed by the reaction of the polyol of the polyurethane prepolymer and the polyisocyanate (hereinafter, this carbon atom is sometimes referred to as "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) refers to 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)). It can be said that the larger the C(A) / C(C), the greater the ratio of carbon atoms (A) per carbon atom (C) in the polyurethane prepolymer (that is, the greater the ratio of aromatic rings contained in the polyester polyol per polyurethane bond). Similar to C(A) / (C(A)+C(B)) in formula (X), C(A) / C(C) in formula (Y) tends to be mainly adjustable by changing the type and content of the polycarboxylic acid constituting the structural unit derived from the polyester polyol, and the type and content of the polyester polyol derived from the polycarboxylic acid.

[0032]

[0033] Another aspect of the present invention relates to a reactive hot melt adhesive. The reactive hot melt adhesive contains a polyurethane prepolymer, and the polyurethane prepolymer has: a polymer chain containing a structural unit derived from a polyol and a structural unit derived from a polyisocyanate; and an isocyanate group bonded to the end of the polymer chain. 13 In C-NMR analysis, when the integrated value of the peak observed in the range of 163 to 170 ppm is defined as C(A), and the integrated value of the peak observed in the range of 150 to 155 ppm is defined as C(C), C(A) and C(C) satisfy the following formula (Y). This reactive hot melt adhesive becomes an adhesive having excellent adhesive strength and excellent elasticity.

[0034] 3.6≤C(A) / C(C)(Y)

[0035] The structural unit derived from the polyol may include a structural unit derived from a polyester polyol having an aromatic ring.

[0036] The reactive hot melt adhesive can be used to bond a plurality of adherends selected from cloth and paper to each other. Here, the combination of the adherends can be cloth and cloth, paper and paper, or cloth and paper. The present invention can also relate to the use of a composition containing the above-mentioned polyurethane prepolymer as a reactive hot melt adhesive for bonding a plurality of adherends selected from cloth and paper to each other, or the use of a reactive hot melt adhesive for bonding a plurality of adherends selected from cloth and paper to each other.

[0037] Another aspect of the present invention relates to an adhesive body. The adhesive body comprises a first adherend, a second adherend, and an adhesive layer for bonding the first adherend and the second adherend to each other. The adhesive layer contains a cured product of the reactive hot-melt adhesive.

[0038] Another aspect of the present invention relates to a garment. The garment comprises the above-mentioned adhesive body, wherein the first adherend and the second adherend may be cloth. The garment may be a non-sewn garment.

[0039] Another aspect of the present invention relates to a method for producing an adhesive body, comprising: a step of forming an adhesive layer by melting the reactive hot-melt adhesive and applying the adhesive layer to a first adherend; a step of obtaining a laminate by placing a second adherend on the adhesive layer and pressing the second adherend; and a step of obtaining the adhesive body by curing the adhesive layer in the laminate.

[0040] Effects of the Invention

[0041] According to the present invention, a reactive hot melt adhesive having excellent adhesive force and excellent elasticity can be provided. Furthermore, according to the present invention, an adhesive body formed by using the reactive hot melt adhesive and a method for manufacturing the same can be provided. Furthermore, according to the present invention, a garment having an adhesive body can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a schematic diagram showing a method for manufacturing an adhesive body according to one embodiment, Figure 1 (a), (b), (c) and (d) are schematic diagrams showing the respective steps.

[0043] Figure 2 The polyurethane prepolymer B of Preparation Example 2 is within the range of 150 to 180 ppm. 13 C-NMR spectroscopy.

[0044] Figure 3 The polyurethane prepolymer E of Preparation Example 5 is within the range of 150 to 180 ppm. 13 C-NMR spectroscopy. DETAILED DESCRIPTION

[0045] Hereinafter, the mode for implementing the present invention will be described in detail. However, the present invention is not limited to the following embodiment.

[0046] In this specification, "polyol" refers to a compound having two or more hydroxyl groups in the molecule.

[0047] In this specification, "polyisocyanate" refers to a compound having two or more isocyanate groups in the molecule.

[0048] In this specification, the determination of "amorphous" and "crystalline" can be determined by the presence or absence of a melting point (Tm) (an endothermic peak accompanying melting in DSC). "Crystallinity" has a melting point (Tm), while "amorphous" does not have a melting point (Tm). In this specification, "amorphous polyester polyol" refers to a polyester polyol that does not have a melting point (Tm), and "crystalline polyester polyol" refers to a polyester polyol that has a melting point (Tm).

[0049] [Reactive hot melt adhesive]

[0050] The reactive hot melt adhesive of one embodiment contains a polyurethane prepolymer. Generally, the reactive hot melt adhesive is high molecular weighted by chemical reaction and can exhibit adhesive strength, etc. In particular, since the polyurethane prepolymer having an isocyanate group solidifies (forms a cured product) by reacting with moisture, the polyurethane prepolymer can function as a reactive hot melt adhesive alone, but the reactive hot melt adhesive may contain components other than the polyurethane prepolymer.

[0051] <Polyurethane prepolymer>

[0052] The polyurethane prepolymer may be, for example, a polyurethane prepolymer having an isocyanate group. The polyurethane prepolymer having an isocyanate group generally has a polymer chain and an isocyanate group, and the polymer chain contains a structural unit derived from a polyol and a structural unit derived from a polyisocyanate. The isocyanate group may be bonded to the end of the polymer chain. The structural unit derived from the polyol may include a structural unit derived from a polyester polyol. The polyurethane prepolymer having a structural unit derived from a polyester polyol may generally be obtained by reacting a polyisocyanate with a polyol containing a polyester polyol. That is, the polyurethane prepolymer may be a reactant of a polyol containing a polyester polyol and a polyisocyanate. In addition, the content of the constituent unit may be adjusted by changing the mixing ratio of the polyester polyol providing the constituent unit and the polyol other than the polyester polyol providing the constituent unit. Furthermore, since a polyurethane bond is formed by the reaction of the polyol and the polyisocyanate, the polymer chain of the polyurethane prepolymer may have a polyurethane bond. Furthermore, by increasing the equivalent of the polyisocyanate relative to the equivalent of the polyol, the isocyanate group may be introduced into the end of the polymer chain.

[0053] Polyurethane prepolymer13 In C-NMR analysis, when the integrated value of the peak observed in the range of 163 to 170 ppm is defined as C(A), and the integrated value of the peak observed in the range of 171 to 176 ppm is defined as C(B), C(A) and C(B) satisfy the following formula (X). The reactive hot melt adhesive containing such a polyurethane prepolymer becomes an adhesive having excellent adhesive force and excellent elasticity.

[0054] 0.36≤C(A) / (C(A)+C(B))(X)

[0055] C(A) / (C(A)+C(B)) refers to 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) (total amount of carbon atoms (A) / total amount of carbon atoms (A) and total amount of carbon atoms (B)). It can be said that the larger C(A) / (C(A)+C(B)) is, the greater the proportion of carbon atoms (A) in the units derived from the polyester polyol constituting the polyurethane prepolymer (that is, the greater the proportion of aromatic rings contained in the polyester polyol).

[0056] C(A) / (C(A)+C(B)) is 0.36 or more, and may be 0.38 or more, or 0.40 or more. If C(A) / (C(A)+C(B)) is 0.36 or more, the reactive hot-melt adhesive tends to have excellent adhesiveness and excellent elasticity. Since the adhesiveness is more excellent, the upper limit of C(A) / (C(A)+C(B)) may be 1.00 or less, 0.95 or less, 0.90 or less, 0.85 or less, 0.80 or less, 0.75 or less, 0.70 or less, 0.65 or less, or 0.60 or less.

[0057] Polyurethane prepolymer 13 In C-NMR analysis, when the integrated value of the peak observed in the range of 150 to 155 ppm is defined as C(C), C(A) and C(C) can satisfy the following formula (Y).

[0058] 3.6≤C(A) / C(C)(Y)

[0059] C(A) / C(C) refers to 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)). It can be said that the larger the C(A) / C(C), the greater the ratio of carbon atoms (A) per carbon atom (C) in the polyurethane prepolymer (i.e., the greater the ratio of aromatic rings contained in the polyester polyol per polyurethane bond).

[0060] C(A) / C(C) may be 3.6 or more, 3.8 or more, or 4.0 or more. If C(A) / C(C) is 3.6 or more, the reactive hot melt adhesive tends to have better adhesion and better elasticity. Since the adhesion is further improved, 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.

[0061] C(A) / (C(A)+C(B)) in formula (X) and C(A) / C(C) in formula (Y) tend to be mainly adjusted by changing the type and content of the polycarboxylic acid constituting the structural unit derived from the polyester polyol, and the type and content of the polyester polyol derived from the polycarboxylic acid. As long as the polyurethane prepolymer satisfies formula (X) and further satisfies formula (Y), the type and content of the structural unit derived from the polyol are not particularly limited. According to the research of the present inventors, it was found that if the proportion of the structural unit derived from the polyester polyol having an aromatic ring in the structural unit derived from the polyol is large, the polyurethane prepolymer tends to easily satisfy formula (X) and formula (Y). Below, taking a polyurethane prepolymer containing such a structural unit as an example, the polyol and polyisocyanate constituting the polyurethane prepolymer are described.

[0062] (a) Ingredient: Polyol

[0063] The constituent units derived from the component (a) include constituent units derived from a polyester polyol having an aromatic ring (hereinafter, sometimes referred to as "component (a1)"). The constituent units derived from the component (a) may further include constituent units derived from a polyol other than the polyester polyol having an aromatic ring (hereinafter, sometimes referred to as "component (a2)").

[0064] 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 may be an amorphous polyester polyol.

[0065] The curing time and viscosity of the reactive hot melt adhesive can be adjusted by including a structural unit derived from the component (a1) in the polymer chain. The component (a1) can be a polycondensation product of a polyol and a polycarboxylic acid. The component (a1) can be a linear polyester diol generated from a diol and a dicarboxylic acid, or a branched polyester triol generated from a triol and a dicarboxylic acid. Furthermore, the branched polyester triol can also be obtained by reacting a diol with a tricarboxylic acid.

[0066] Examples of the polyol include: ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, each isomer of butanediol, each isomer of pentanediol, each isomer of hexanediol, 2,2-dimethyl-1,3-propylene glycol, 2-methyl propanediol, 2,4,4-trimethyl-1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol, 1,4-cyclohexanedimethanol and other aliphatic or alicyclic diols; 4,4'-dihydroxydiphenylpropane, bisphenol A, bisphenol F, catechol, resorcinol, hydroquinone and other aromatic diols (diols having aromatic rings), etc. The polyol may be used alone or in combination of two or more. Among these, aliphatic diols are preferred, and aliphatic diols having 2 to 6 carbon atoms are more preferred.

[0067] Examples of the polycarboxylic acid include polycarboxylic acids in which the carbon atom of the carbonyl group (of the carboxylic acid) is directly bonded to the carbon atom constituting the aromatic ring, such as phthalic acid, isophthalic acid, terephthalic acid, and 1,2,4-benzenetricarboxylic acid (hereinafter, sometimes referred to as “aromatic polycarboxylic acids” depending on the circumstances); and polycarboxylic acids in which the carbon atom of the carbonyl group (of the carboxylic acid) is directly bonded to the carbon atom constituting the aliphatic group, such as maleic acid, fumaric acid, aconitic acid, 1,2,3-propanetricarboxylic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, cyclohexane-1,2-dicarboxylic acid, and 1,4-cyclohexadiene-1,2-dicarboxylic acid (hereinafter, sometimes referred to as “aliphatic polycarboxylic acids” depending on the circumstances). Aromatic polycarboxylic acid can 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, or can be at least one selected from the group consisting of phthalic acid, isophthalic acid and terephthalic acid. Polycarboxylic acid can be used alone or in combination of two or more. The adjustment of C(A) / (C(A)+C(B)) in formula (X) and C(A) / C(C) in formula (Y) can be carried out by adjusting the ratio of aromatic polycarboxylic acid.

[0068] Instead of the polycarboxylic acid, polycarboxylic acid derivatives such as carboxylic anhydride and compounds in which a part of the carboxyl group is esterified may be used. Examples of the polycarboxylic acid derivatives include phthalic anhydride, dimethyl terephthalate, dodecyl maleic acid, and octadecenyl maleic acid.

[0069] The component (a1) may be a polycondensation product of a polyol and a polycarboxylic acid including an aromatic polycarboxylic acid.

[0070] In the polycondensation reaction product of a polyol and a polycarboxylic acid, the content of the constituent units derived from an aromatic polycarboxylic acid may be, for example, 10 to 60 mol% based on the total amount of the constituent units constituting the component (a1) (polycondensation reaction product). The content of the constituent units derived from a compound having an aromatic ring may be 15 mol% or more, or 20 mol% or more, or 55 mol% or less, or 50 mol% or less, based on the total amount of the constituent units constituting the component (a1).

[0071] When the component (a1) is a polycondensation reaction product of a polyol and a polycarboxylic acid including 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), the content of the constituent units derived from the aromatic polycarboxylic acid may be 20 to 100 mol %, 25 to 100 mol % or 30 to 100 mol %, based on the total amount of the constituent units derived from the polycarboxylic acid.

[0072] From the viewpoint of adhesive strength, the number average molecular weight (Mn) of the component (a1) may be 500 to 12000. The number average molecular weight (Mn) of the component (a1) may be 1000 or more, 1500 or more, or 1800 or less, 11000 or less, 10000 or less, or 9000 or less. In this specification, Mn is a value measured by gel permeation chromatography (GPC) and converted into standard polystyrene.

[0073] In this specification, the GPC measurement for obtaining the number average molecular weight (Mn) can be performed under the following conditions, for example.

[0074] Columns: "Gelpack GLA130-S", "Gelpack GLA150-S" and "Gelpack GLA160-S" (manufactured by Hitachi Chemical Co., Ltd., packed columns for HPLC)

[0075] Eluent: Tetrahydrofuran

[0076] Flow rate: 1.0mL / min

[0077] Column temperature: 40℃

[0078] Detector: RI

[0079] The content of component (a1) (constituent units derived from component (a1)) may be 50% by mass or more, 55% by mass or more, 60% by mass or more, 65% by mass or more, 70% by mass or more, or 75% by mass or more, based on the total amount of component (a) (constituent units derived from component (a)). If the content of component (a1) is 50% by mass or more based on the total amount of component (a), the obtained polyurethane prepolymer (reactive hot-melt adhesive) tends to have excellent initial adhesion. On the other hand, from the viewpoint of operability, the upper limit of the content of component (a1) (constituent units derived from component (a1)) may be 100% by mass or less, 95% by mass or less, or 90% by mass or less, based on the total amount of component (a) (constituent units derived from component (a)).

[0080] Since the adhesive force is better and the stretchability is better, when the total amount of component (a) (constituent units derived from component (a)) is set to 100 mol%, the content of component (a1) (constituent units derived from component (a1)) can 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 less, or 100 mol% or less, 95 mol% or less, or 90 mol% or less.

[0081] The component (a2) is a polyol other than a polyester polyol having an aromatic ring. Examples of the component (a2) include polyester polyols, polyether polyols, polyether ester polyols, polyurethane polyols, polycarbonate polyols, and polyolefin polyols that do not have an aromatic ring.

[0082] From the viewpoint of improving the initial adhesive force, the component (a) may contain a polyether polyol having an aromatic ring as the component (a2). 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 polyol obtained by modifying bisphenol A or bisphenol F with an alkylene oxide, more specifically, a polyol obtained by modifying ethylene oxide or propylene oxide. The component (a) contains such a polyether polyol having a bisphenol skeleton as the component (a2), which tends to have better adhesive force.

[0083] The content of the polyether polyol having a bisphenol skeleton may be 0 to 10% by mass, or may be 1% by mass or more, 2% by mass or more, or 3% by mass or less, or 8% by mass or less, 6% by mass or less, or 5% by mass or less, based on the total amount of component (a) (constituent units derived from component (a)).

[0084] When the total amount of component (a) (constituent units derived from component (a)) is set to 100 mol%, the content of the polyether polyol having an aromatic ring containing a bisphenol skeleton can be 0 to 10 mol%, or it can be 1 mol% or more, 2 mol% or more, or 3 mol% or less, or 8 mol% or less, 6 mol% or less, or 5 mol% or less.

[0085] From the viewpoint of reducing the viscosity of the polyurethane prepolymer, the number average molecular weight (Mn) of the component (a2) may be 100 to 10000. The number average molecular weight (Mn) of the component (a2) may be 400 or more or 1000 or more, or 8000 or less or 5000 or less. In this specification, Mn is a value measured by gel permeation chromatography (GPC) and converted into standard polystyrene.

[0086] The content of component (a2) (constituent units derived from component (a2)) may be 0 to 50% by mass, or may be 5% or more, or 10% or more, or may be 45% or less, 40% or less, 35% or less, 30% or less, or 25% or less, based on the total amount of component (a) (constituent units derived from component (a)).

[0087] When the total amount of component (a) (constituent units derived from component (a)) is set to 100 mol%, the content of component (a2) (constituent units derived from component (a2)) can be 0 to 50 mol%, or it can be greater than 5 mol% or greater than 10 mol%, or it can be less than 45 mol%, less than 40 mol%, less than 35 mol%, less than 30 mol% or less than 25 mol%.

[0088] (b) Ingredient: Polyisocyanate

[0089] As long as the polyisocyanate is a compound having two or more isocyanate groups, it can be used without particular limitation. The polyisocyanate may be a compound having two isocyanate groups (diisocyanate). As the polyisocyanate, for example, aromatic isocyanates such as diphenylmethane diisocyanate (4,4'-diphenylmethane diisocyanate), dimethyldiphenylmethane diisocyanate, toluene diisocyanate, xylene diisocyanate, and p-phenylene diisocyanate can be cited; alicyclic isocyanates such as dicyclohexylmethane diisocyanate and isophorone diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate, etc. From the viewpoint of reactivity and adhesion, the polyisocyanate preferably contains an aromatic diisocyanate, and more preferably contains diphenylmethane diisocyanate. One polyisocyanate may be used alone, or two or more polyisocyanates may be used in combination.

[0090] The polyurethane prepolymer can be synthesized by reacting the component (a) containing a predetermined content of the component (a1) with the component (b). The polyurethane prepolymer has: a polymer chain containing a structural unit derived from the component (a) and a structural unit derived from the component (b); and an isocyanate group bonded to the end of the polymer chain, wherein the component (a) contains a structural unit derived from the component (a1). When synthesizing such a polyurethane prepolymer, the equivalent ratio of the isocyanate group (NCO) of the component (b) to the hydroxyl group (OH) of the component (a) (isocyanate group (NCO) equivalent of the component (b) / hydroxyl group (OH) equivalent of the component (a), NCO / OH) may be 1.1 or more, or 1.1 to 2.1. When NCO / OH is 1.1 or more, the polyurethane prepolymer has an isocyanate group bonded to the end of the polymer chain, and the increase in the viscosity of the polyurethane prepolymer can be suppressed, and the workability tends to be further improved. When NCO / OH is 2.1 or less, the reactive hot-melt adhesive is less likely to foam during moisture curing reaction, and a decrease in adhesive strength tends to be easily suppressed.

[0091] The reaction temperature and time of the components (a) and (b) when synthesizing the polyurethane prepolymer are not particularly limited, and may be, for example, 85 to 120° C. and 0.1 minute to 48 hours.

[0092] The polyurethane prepolymer may satisfy both the following conditions (i) and (ii). A reactive hot-melt adhesive containing such a polyurethane prepolymer has a more excellent initial adhesive force and a more excellent workability.

[0093] Condition (i): The melt viscosity at 120° C. is 1 to 30 Pa·s.

[0094] Condition (ii): The melt viscosity at 80°C is 100 Pa·s or more.

[0095] Regarding condition (i), the melt viscosity of the polyurethane prepolymer at 120°C is 1 to 30 Pa·s. If the melt viscosity of the polyurethane prepolymer at 120°C is 1 to 30 Pa·s, the viscosity is sufficiently low, so the workability (dispensability during coating, stringiness, 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 less, or 28 Pa·s or less, 25 Pa·s or less, 20 Pa·s or less, or 15 Pa·s or less.

[0096] Regarding condition (ii), the melt viscosity of the polyurethane prepolymer at 80°C is 100 Pa·s or more. If the melt viscosity of the polyurethane prepolymer at 80°C is 100 Pa·s or more, the viscosity required for adhesion will be exhibited at an early stage, and as a result, the initial adhesion will be excellent. The melt viscosity at 80°C can be 110 Pa·s or more, 120 Pa·s or more, 130 Pa·s or more, or 140 Pa·s or more. There is no particular limit to the upper limit of the melt viscosity at 80°C, for example, it can be 1000 Pa·s or less, or it can be 800 Pa·s or less, 600 Pa·s or less, 500 Pa·s or less, or 400 Pa·s or less. In addition, the melt viscosity at 120°C is the viscosity measured in a rotational rheometer device.

[0097] The melt viscosity of the polyurethane prepolymer at 120°C and the melt viscosity at 80°C are viscosities measured using a rotational rheometer device, and are measured, for example, by the following method. In addition, a 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.

[0098] Rotational rheometer device: DHR-2 (TAInstruments)

[0099] ·Geometric shape: Φ20mm(2°) cone plate

[0100] GAP: 57μm

[0101] Shear speed: 33 (1 / s)

[0102] Melt viscosity at 120°C: The value measured after the polyurethane prepolymer (reactive hot melt adhesive) is kept at 120°C for 5 minutes.

[0103] Melt viscosity at 80°C: The value measured after the polyurethane prepolymer (reactive hot melt adhesive) is kept at 80°C for 5 minutes.

[0104] The melt viscosity of the polyurethane prepolymer can be adjusted mainly by changing the type and content of the structural unit derived from the polyol. As long as the polyurethane prepolymer satisfies conditions (i) and (ii), the type and content of the structural unit derived from the polyol are not particularly limited. In addition, according to the research of the present inventors, it is found that if the structural unit derived from the polyol includes a structural unit derived from a polyester polyol having an aromatic ring, the polyurethane prepolymer tends to easily satisfy conditions (i) and (ii), and further, in the polyurethane prepolymer that satisfies conditions (i) and (ii), the polyurethane prepolymer tends to easily satisfy formula (X) and formula (Y).

[0105] From the viewpoint of promoting the curing of the polyurethane prepolymer and showing higher adhesive force, the reactive hot melt adhesive may further contain a catalyst. As the catalyst, for example, dibutyltin dilaurate, dibutyltin octoate, dimethylcyclohexylamine, dimethylbenzylamine, trioctylamine, dimorpholino diethyl ether (bis (2-morpholino ethyl) ether) and the like can be cited. Based on the total amount of the reactive hot melt adhesive, the content of the catalyst may be 0.001 to 0.5 mass %.

[0106] From the viewpoint of improving the rubber elasticity of the formed adhesive layer and further improving the impact resistance, the reactive hot melt adhesive may further contain a thermoplastic polymer. Examples of the thermoplastic polymer include polyurethane, ethylene copolymers, propylene copolymers, vinyl chloride copolymers, acrylic copolymers, and styrene-conjugated diene block copolymers. 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.

[0107] From the viewpoint of imparting a stronger adhesive force to the formed adhesive layer, the reactive hot melt adhesive may further contain a tackifier resin. As the tackifier resin, for example, rosin resin, rosin ester resin, hydrogenated rosin ester resin, terpene resin, terpene phenolic resin, hydrogenated terpene resin, petroleum resin, hydrogenated petroleum resin, coumarone resin, ketone resin, styrene resin, modified styrene resin, xylene resin, epoxy resin, etc. can be cited. Based on the total amount of the reactive hot melt adhesive, the content of the tackifier resin can be 0.1 to 50% by mass.

[0108] The reactive hot melt adhesive may further contain other components as required. Examples of other components include antioxidants, pigments, ultraviolet absorbers, surfactants, flame retardants, fillers, photochromic agents, thermal color inhibitors, fragrances, developers, and thermal crosslinking agents. The content of other components may be 0.001 to 10% by mass based on the total amount of the reactive hot melt adhesive.

[0109] Reactive hot melt adhesives may be composed of a single polyurethane prepolymer and may contain other components in addition to the polyurethane prepolymer. In the case where the reactive hot melt adhesive is composed of a single polyurethane prepolymer, if the polyurethane prepolymer satisfies both conditions (i) and (ii), the reactive hot melt adhesive also satisfies both conditions (i) and (ii). Furthermore, even if the reactive hot melt adhesive contains other components in addition to the polyurethane prepolymer, it may satisfy both conditions (i) and (ii) to become a reactive hot melt adhesive with excellent initial adhesiveness and excellent operability, and the reactive hot melt adhesive may satisfy both conditions (i) and (ii). In addition, a reactive hot melt adhesive containing any polyurethane prepolymer and other components may also satisfy both conditions (i) and (ii) to become an adhesive with excellent initial adhesiveness and excellent operability.

[0110] That is, the reactive hot-melt adhesive may satisfy both the following conditions (i) and (ii). The reactive hot-melt adhesive may contain a polyurethane prepolymer.

[0111] Condition (i): The melt viscosity at 120° C. is 1 to 30 Pa·s.

[0112] Condition (ii): The melt viscosity at 80°C is 100 Pa·s or more.

[0113] 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 preferred ranges of the melt viscosity at 120° C. and the melt viscosity at 80° C. of the polyurethane prepolymer described above. Furthermore, the measurement conditions of the melt viscosity of the reactive hot melt adhesive are also the same as the measurement conditions of the melt viscosity of the polyurethane prepolymer. Therefore, repeated descriptions are omitted here.

[0114] The content of the polyurethane prepolymer based on the total amount of the reactive hot-melt adhesive can be 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, or 100% by mass. Since the content of the polyurethane prepolymer is within this range, the melt viscosity of the reactive hot-melt adhesive can be easily adjusted to satisfy both conditions (i) and (ii) by adjusting the melt viscosity of the polyurethane prepolymer. In addition, when the melt viscosity of the polyurethane prepolymer satisfies both conditions (i) and (ii), the melt viscosity of the reactive hot-melt adhesive can also easily satisfy both conditions (i) and (ii).

[0115] Since the isocyanate group of the polyurethane prepolymer contained in the reactive hot melt adhesive reacts with moisture in the air or moisture on the surface of the adherend, the reactive hot melt adhesive can be cured by, for example, leaving it at a temperature of 23° C. and 50% RH (relative humidity) for 24 hours (curing). In this way, a cured product of the reactive hot melt adhesive can be obtained.

[0116] The reactive hot melt adhesive can be used by, for example, applying it to an adherend after melting it at 60 to 130° C. There is no particular limitation on the coating method, and for example, a method using a coating device such as a rod coater, a die coater, a roll coater, or a sprayer can be cited. When coating a small area such as a small part, a dispenser is preferably used. The coating pattern of the reactive hot melt adhesive can be appropriately set, and for example, a dot-shaped, line-shaped, zigzag-shaped, flat-shaped, curved-shaped, or other coating pattern can be cited.

[0117] Reactive hot melt adhesives can be used to bond various adherends via the cured product (adhesive layer) of the reactive hot melt adhesive. As adherends, for example, metal substrates such as SUS and aluminum; non-metal substrates such as cloth, paper, polycarbonate, polyamide, polyetherimide, glass, carbon fiber, etc. can be listed. Among these, the adherend can be, for example, cloth or paper. Reactive hot melt adhesives can be preferably used to bond a plurality of adherends selected from cloth and paper to each other. At this time, the combination of adherends can be cloth and cloth, paper and paper, or cloth and paper. Reactive hot melt adhesives can be preferably used for clothing (accessories) such as clothes, straps, bags, wallets, interior decorations, various covers, housings, wearable devices, etc., and can be particularly preferably used for clothing.

[0118] The reactive hot melt adhesive can be formed into a film and used as an adhesive film. Such an adhesive film can be obtained, for example, by coating the reactive hot melt adhesive on a support film such as a PET (polyethylene terephthalate) film and forming an adhesive layer. The thickness of the adhesive layer (adhesive film) can be more than 10 μm, more than 20 μm, or more than 30 μm, or less than 300 μm, less than 250 μm, or less than 200 μm. If the film is thick, it tends to be able to further ensure the adhesive force, and if the film is thin, it tends to be easier to ensure elasticity.

[0119] [Adhesive body and method for producing the same]

[0120] An adhesive body of one embodiment comprises a first adherend, a second adherend, and an adhesive layer for bonding the first adherend and the second adherend to each other. The adhesive layer contains a cured product of the reactive hot melt adhesive. Articles having the adhesive body include, for example, clothing (particularly non-sewn clothing), semiconductor devices, electronic devices, and the like.

[0121] The first adherend and the second adherend can be the same as the adherends exemplified in the above-mentioned adherends. The first adherend and the second adherend can be, for example, cloth or paper, and the combination of the first adherend and the second adherend can be cloth and cloth, paper and paper, or cloth and paper. When the article having the adhesive is clothing, the first adherend and the second adherend are cloth.

[0122] The adhesive body of this embodiment can be manufactured by a method, which includes: a process of melting the above-mentioned reactive hot-melt adhesive and applying it to a first adhesive body to form an adhesive layer; a process of obtaining a laminated body by arranging a second adhesive body on the adhesive layer and crimping the second adhesive body; and a process of obtaining an adhesive body by curing the adhesive layer.

[0123] The temperature of the molten reactive hot melt adhesive may be, for example, 60 to 130° C. As a method of applying the reactive hot melt adhesive to the first adherend, for example, a method using a coating device such as a die coater, a roll coater, or a sprayer may be cited. When applying to a narrow area such as a small part, a dispenser is preferably used.

[0124] As a method of pressure-bonding the second adherend, for example, there can be mentioned a method of pressure-bonding using a pressure roller or the like.

[0125] The reactive hot melt adhesive in the adhesive layer can be cured by, for example, leaving it at a temperature of 23° C. and 50% RH (relative humidity) for 24 hours (curing). Thus, the adhesive layer can contain a cured product of the reactive hot melt adhesive.

[0126] Figure 1 is a schematic diagram showing a method for manufacturing an adhesive body according to one embodiment, Figure 1 (a), (b), (c) and (d) are schematic diagrams showing the respective steps. Figure 1 A method for producing an adhesive body using elastic fabric as a first adherend and a second adherend will be described.

[0127] First, the elastic fabric 1 is placed along the jig 10 (refer to Figure 1 Next, the reactive hot melt adhesive of this embodiment is applied to a predetermined portion of the elastic fabric 1 to form an adhesive layer 4 (see Figure 1 (b)). The material and shape of the clamp 10 are not particularly limited and can be appropriately selected according to the purpose. The coating of the reactive hot melt adhesive can be performed 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 bonded together through the adhesive layer 4 while applying pressure with a roller from above the elastic fabric 2 to obtain a laminate 20 (see Figure 1(c) and (d)). After that, by placing (curing) the laminate 20, the reactive hot melt adhesive in the adhesive layer 4 is cured by moisture, thereby obtaining an adhesive body in which the elastic fabrics are bonded to each other. The adhesive layer 4 in the adhesive body contains a cured product of the reactive hot melt adhesive.

[0128] exist Figure 1 In (b), an adhesive film composed of a reactive hot melt adhesive formed in advance on a releasable substrate may be transferred to the elastic fabric 1 to form the adhesive layer 4. Furthermore, an adhesive may be provided on the elastic fabric 2 to be bonded to the elastic fabric 1.

[0129] [Clothing]

[0130] A garment according to one embodiment includes the above-mentioned adhesive body. In this case, the first adherend and the second adherend may be cloth. The garment may be unstitched garment.

[0131] [analyze]

[0132] The polyurethane prepolymer contained in the reactive hot melt adhesive of the present embodiment can be determined by, for example, performing solution NMR measurement to determine the constituent components of the polyurethane prepolymer. When the reactive hot melt adhesive of the present embodiment contains components other than the polyurethane prepolymer, for example, the polyurethane prepolymer can be separated by using fractionation liquid chromatography (known methods such as GPC), and the solvent is removed by distillation, and then the constituent components of the polyurethane prepolymer can be determined by performing solution NMR measurement. In addition, by using the same method, components other than the polyurethane prepolymer contained in the reactive hot melt adhesive can also be determined.

[0133] For the cured product of the reactive hot-melt adhesive of the present embodiment, for example, a solvent such as tetrahydrofuran that dissolves the uncured components of the cured product but does not easily dissolve the cured product itself is used to extract only the uncured components, and the residual undissolved components (cured product components) are decomposed by pyridine to cut the polyurethane bonds, thereby determining the constituent components of the polyurethane prepolymer before curing.

[0134] Example

[0135] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the Examples.

[0136] (Production Examples 1 to 5)

[0137] <Preparation of polyurethane prepolymer (reactive hot melt adhesive)>

[0138] Using the types and weight parts of polyols and polyisocyanates shown in Table 1, polyurethane prepolymers A to E of Manufacturing Examples 1 to 5 were prepared. More specifically, for the polyols that had been dehydrated in advance using a vacuum dryer, polyisocyanates were added to a reaction vessel so that the equivalent ratio of the isocyanate group of the polyisocyanate to the hydroxyl group of the polyol ((NCO) equivalent / (OH) equivalent) reached the value shown in Table 1, and mixed at 110°C for 1 hour until it was uniform. Then, the mixture was further degassed and stirred at 110°C for 1 hour to obtain a polyurethane prepolymer. As shown in Table 1, since the (NCO) equivalent / (OH) equivalent is greater than 1, it can be inferred that the obtained polyurethane prepolymer has: a polymer chain containing structural units derived from polyols and structural units derived from polyisocyanates; and an isocyanate group bonded to the end of the polymer chain. Hereinafter, the obtained polyurethane prepolymer was used directly as a reactive hot melt adhesive.

[0139] The details of the components shown in Table 1 are as follows.

[0140] (a) Polyols

[0141] (a1) Polyester polyol having an aromatic ring

[0142] (a1)-1: Amorphous polyester polyol having an aromatic ring and containing dicarboxylic acid (adipic acid and isophthalic acid) and diol (ethylene glycol and neopentyl glycol) as main components (number of hydroxyl groups: 2, number average molecular weight: 2000, content of structural units derived from compounds 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 structural units derived from dicarboxylic acid), melting point (Tm): none)

[0143] (a1)-2: Amorphous polyester polyol having an aromatic ring and containing dicarboxylic acid (phthalic anhydride) and diol (ethylene glycol and diethylene glycol) as main components (number of hydroxyl groups: 2, number average molecular weight: 2000, content of structural units derived from compounds having aromatic rings: 50 mol% (based on the total amount of structural units constituting the amorphous polyester polyol), 100 mol% (based on the total amount of structural units derived from dicarboxylic acid), melting point (Tm): none)

[0144] (a2) Polyols other than (a1)

[0145] (a2)-1: Amorphous polyester polyol having no aromatic ring and containing dicarboxylic acid (adipic acid) and diol (1,4-butanediol and neopentyl glycol) as main components (number of hydroxyl groups: 2, number average molecular weight: 5000, melting point (Tm): none)

[0146] (a2)-2: A 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)

[0147] (a2)-3: Amorphous polyether polyol having an aromatic ring (bisphenol A·PO type) (manufactured by ADEKA CORPORATION, trade name: BPX-11, number of hydroxyl groups: 2, melting point (Tm): none)

[0148] (b) Polyisocyanate

[0149] (b)-1: diphenylmethane diisocyanate (manufactured by Tosoh Corporation, trade name: Millionate MT, number of isocyanate groups: 2)

[0150] < 13 C-NMR analysis>

[0151] Polyurethane prepolymers A to E were 13 C-NMR analysis was performed using AVANCENEO manufactured by Bruker Japan KK (probe: CryoProbe TM ) as a nuclear magnetic resonance spectrometer (NMR), the measurement was carried out under the following conditions 13 C-NMR analysis.

[0152] (Measurement conditions)

[0153] · 13 C-NMR quantitative spectroscopy: inverse gate decoupling method

[0154] Resonance frequency: 100MHz

[0155] Waiting time (d1): 5 seconds

[0156] Solvent: heavy chloroform (CDCl3)

[0157] Sample concentration: 100mg / 0.6ml-CDCl3, also contains 10mgCr(acac)3 as a relaxation reagent

[0158] Chemical shift standard: Set the peak of tetramethylsilane (TMS) to 0.00 ppm

[0159] ·Measurement temperature: 23℃

[0160] Cumulative times: 400 times

[0161] Figure 2 The polyurethane prepolymer B of Preparation Example 2 is within the range of 150 to 180 ppm.13 C-NMR spectrum. Figure 2 of 13 In the C-NMR spectrum, when the integral value of the peak observed in the range of 171 to 176 ppm (C(B)) is set to 10.000, the integral value of the peak observed in the range of 163 to 170 ppm (C(A)) and the integral value of the peak observed in the range of 150 to 155 ppm (C(C)) are 33.039 and 5.081, respectively. Figure 3 The polyurethane prepolymer E of Preparation Example 5 is within the range of 150 to 180 ppm. 13 C-NMR spectrum. Figure 3 of 13 In the C-NMR spectrum, when the integral value (C(B)) of the peak observed in the range of 171 to 176 ppm is set to 10.000, the integral value (C(A)) of the peak observed in the range of 163 to 170 ppm and the integral value (C(C)) of the peak observed in the range of 150 to 155 ppm are 4.805 and 1.564, respectively. The results are shown in Table 1. Based on these values, C(A) / (C(A)+C(B)) and C(A) / C(C) were calculated. The results are shown in Table 1.

[0162] (Examples 1 to 3 and Comparative Examples 1 and 2)

[0163] <Evaluation of reactive hot-melt adhesives>

[0164] Initial adhesion and final adhesion

[0165] The reactive hot melt adhesive (polyurethane prepolymers A to E) of Examples 1 to 3 and Comparative Examples 1 and 2 were melted at 120°C and then coated on an elastic fabric (spandex, manufactured by TORAY OPELONTEX CO., LTD., LYCRA (registered trademark)) and coated with a rod coater to a thickness of 80 μm to form an adhesive layer. A crimped body was obtained by arranging the same elastic fabric on the formed adhesive layer and crimping it at 120°C. The adhesive force of the crimped body 5 minutes after the crimping moment was measured using a dynamometer (DS250N manufactured by IMADA CO., LTD.) and used as the initial adhesive force of the reactive hot melt adhesive. Next, the crimped body was cured in a constant temperature chamber at 23°C and 50% RH for one day, and the adhesive layer was cured to produce an adhesive body. The adhesive strength of the adhesive was measured by a T-type peel strength test using a tensile tester (EZ-Test EZ-SX manufactured by Shimadzu Corporation) at a measuring temperature of 25°C and a tensile speed of 100 mm / min, and the result was taken as the final adhesive strength. The results are shown in Table 1.

[0166] Elongation at break

[0167] The reactive hot melt adhesives (polyurethane prepolymers A to E) of Examples 1 to 3 and Comparative Examples 1 and 2 were melted at 100°C to form a film with a thickness of 100 μm, and then the formed film was left to stand for two days in a constant temperature and humidity chamber at a temperature of 23°C and a humidity of 50% to cure. The cured film was punched out with a No. 1 dumbbell to prepare a test piece, and the elongation at break (%) of the test piece was measured using Autograph AGS-X (manufactured by Shimadzu Corporation) in accordance with JIS K-6251. The results are shown in Table 1.

[0168] [Table 1]

[0169]

[0170] Polyurethane prepolymers A to E 13 According to the results of C-NMR analysis, the C(A) / (C(A)+C(B)) of the polyurethane prepolymers A to C is 0.36 or more, and the C(A) / C(C) is 3.6 or more. It was found that the reactive hot melt adhesives of Examples 1 to 3 using such polyurethane prepolymers tend to have excellent initial adhesive force and final adhesive force compared to the reactive hot melt adhesives of Comparative Examples 1 and 2 using polyurethane prepolymers that do not meet the specified requirements. In addition, it was found that the reactive hot melt adhesives of Examples 1 to 3 tend to have a sufficiently high level of elongation at break. Based on these results, it was confirmed that the reactive hot melt adhesive of the present invention has excellent adhesive force (both initial adhesive force and final adhesive force) and excellent elasticity.

[0171] Explanation of symbols

[0172] 1, 2-elastic fabric, 4-adhesive layer, 10-clamp, 20-laminated body.

Claims

1. A reactive hot melt adhesive comprising a polyurethane prepolymer, The polyurethane prepolymer is 13 In C-NMR analysis, when the integrated value of the peak observed in the range of 163 to 170 ppm is defined as C(A), and the integrated value of the peak observed in the range of 171 to 176 ppm is defined as C(B), C(A) and C(B) satisfy the following formula (X): 0.36≤C(A) / (C(A)+C(B))≤0.44(X), C(A) / (C(A)+C(B)) is also the ratio of the total amount of carbon atoms (A), which are carbon atoms belonging to 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, to the sum of the total amount of carbon atoms (A) and the total amount of carbon atoms (B), wherein the carbon atoms (A) are carbon atoms belonging to the carbonyl group directly bonded to the carbon atom constituting the aliphatic group among the carbon atoms of the carbonyl group of the ester bond of the polyester polyol. The polyurethane prepolymer has structural units derived from polyols, The structural unit derived from the polyol includes a structural unit derived from a polyester polyol having an aromatic ring, When the total amount of the structural units derived from the polyol is 100 mol %, the content of the structural units derived from the polyester polyol having an aromatic ring is 75 mol % to 95 mol %.

2. The reactive hot-melt adhesive according to claim 1, wherein The polyurethane prepolymer is 13 In C-NMR analysis, when the integrated value of the peak observed in the range of 150 to 155 ppm is defined as C(C), the C(A) and the C(C) satisfy the following formula (Y): 3.6≤C(A) / C(C)(Y).

3. The reactive hot-melt adhesive according to claim 1 or 2, which is used for bonding a plurality of adherends selected from cloth and paper to each other.

4. An adhesive body, comprising: The first adherend; a second adherend; and an adhesive layer for bonding the first adherend and the second adherend to each other, The adhesive layer contains a cured product of the reactive hot-melt adhesive according to claim 1 or 2.

5. A garment comprising the adhesive body according to claim 4, The first adherend and the second adherend are cloths.

6. A method for manufacturing an adhesive body, comprising: A step of forming an adhesive layer by melting the reactive hot-melt adhesive according to claim 1 or 2 and applying it to a first adherend; a step of obtaining a laminate by disposing a second adherend on the adhesive layer and press-bonding the second adherend; and A step of obtaining an adhesive body by curing the adhesive layer in the laminated body.

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