JP2020132687A - Moisture-curable hot-melt adhesive and bonded body - Google Patents

Abstract

To provide a moisture-curable hot-melt adhesive which has high initial adhesiveness and is excellent in flexibility after curing.SOLUTION: The moisture-curable hot-melt adhesive contains: a urethane prepolymer which has a polyurethane chain containing a constituent unit derived from a polyol and a constituent unit derived from a polyisocyanate, and an isocyanate group bonded to a terminal of the polyurethane chain; and a rosin compound having no hydroxyl group.SELECTED DRAWING: None

Description

The present invention relates to moisture-curable hot melt adhesives and adhesives.

Since the hot melt adhesive is a solvent-free adhesive, it has a small load on the environment and the human body and can be adhered for a short time, so that it is an adhesive 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. A reactive hot-melt adhesive containing a urethane prepolymer as a main component can exhibit a certain degree of adhesive strength (initial adhesiveness) 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 the moisture in the air or the moisture on the surface of the adherend to increase the molecular weight, and crosslinks occur, so that the adhesive is cured and exhibits adhesiveness. Such an adhesive is called a "moisture-curable hot melt adhesive". Moisture-curable hot-melt adhesives containing urethane prepolymers as the main component tend to exhibit good adhesive strength even when heated.

Further, in order to improve the adhesiveness of the moisture-curable hot melt adhesive, it has been studied to use a urethane prepolymer having a structure derived from a rosin compound having a hydroxyl group (see, for example, Patent Documents 1 to 3). ..

Japanese Unexamined Patent Publication No. 4-198387 Japanese Unexamined Patent Publication No. 2003-89782 JP-A-2010-126615

In recent years, moisture-curable hot melt adhesives are also being used for cloths, papers and the like, which are materials for clothing, diapers and the like. From the viewpoint of workability, the adhesive used for the joints of clothing such as sportswear and innerwear exhibits adhesiveness immediately after the cloths are attached to each other and has excellent adhesiveness after moisture curing. Is required. Further, such an adhesive needs to form a cured product having excellent flexibility in order to improve the comfort in addition to the adhesiveness to the cloth.

Therefore, it is a main object of the present invention to provide a moisture-curable hot melt adhesive having high initial adhesiveness and excellent flexibility after curing.

One aspect of the present invention is a polyurethane chain containing a constituent unit derived from a polyol and a constituent unit derived from polyisocyanate, a urethane prepolymer having an isocyanate group bonded to the end of the polyurethane chain, and a rosin compound having no hydroxyl group. To provide a moisture-curable hot melt adhesive containing and.

The polyol may contain at least one selected from the group consisting of polybutadiene polyols and hydrogenated polybutadiene polyols. Further, the polyol may include a hydrogenated polybutadiene polyol.

The content of the rosin compound may be 65% by mass or less based on the total mass of the polyol and the rosin compound.

Moisture-curable hot melt adhesives may be used to bond multiple fabrics together.

In another aspect, the present invention provides an adhesive comprising a plurality of fabrics and a cured product of the moisture-curable hot melt adhesive described above that adheres the plurality of fabrics to each other.

According to the present invention, there is provided a moisture-curable hot melt adhesive having high initial adhesiveness and excellent flexibility after curing. Further, according to the present invention, an adhesive using such a moisture-curable hot melt adhesive is provided.

It is a schematic diagram which shows an example of the process of manufacturing the adhesive body which concerns on this embodiment.

Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

As used herein, "polyisocyanate" means a compound having an average of more than 1 hydroxyl group in the molecule, and "polyisocyanate" means a compound having an average of more than 1 isocyanate group in the molecule. As used herein, the term "initial adhesiveness" means the adhesiveness after the adherends are pressure-bonded to each other via an adhesive layer formed from an adhesive and before the adhesive layer is moisture-cured.

[Moisture-curing hot melt adhesive]
The moisture-curable hot-melt adhesive according to an embodiment (hereinafter, may be simply referred to as “hot-melt adhesive”) is a polyurethane chain containing a constituent unit derived from a polyol and a constituent unit derived from polyisocyanate, and a polyurethane chain. A urethane prepolymer having an isocyanate group bonded to the end of the polyurethane chain (hereinafter, may be simply referred to as “urethane prepolymer”) and a rosin compound having no hydroxyl group (hereinafter, may be simply referred to as “rosin compound”). ) And.

(Rosin compound without hydroxyl group)
The rosin compound according to the present embodiment is a compound having a rosin skeleton derived from rosin and having no hydroxyl group. The rosin skeleton may include a rosin ester structure. The unsaturated double bond of the rosin backbone may be hydrogenated. That is, the rosin compound may be a hydrogenated rosin ester.

The acid value of the rosin compound may be 20 mgKOH / g or less, 1 to 15 mgKOH / g, or 2 to 10 mgKOH / g from the viewpoint of the balance between adhesiveness and flexibility after curing. The acid value can be measured according to JIS K 0070.

The softening point of the rosin compound may be 80 to 110 ° C., 90 to 105 ° C., or 90 to 100 ° C. from the viewpoint of improving the initial adhesiveness. The softening point can be measured by the ring-and-ball method according to JIS K 5601-2-2. Since such a rosin compound is solid at room temperature and liquid at the temperature at which the hot melt adhesive is applied (for example, 100 to 120 ° C.), when the hot melt adhesive after application is cooled and solidified. In addition, the storage elasticity increases, and the initial adhesiveness can be easily improved.

As the rosin compound, a commercially available product can be used as it is. Examples of commercially available products of the hydroxyl group-containing rosin compound according to the present embodiment include trade names "KE-100", "KE-311", and "KE-590" manufactured by Arakawa Chemical Industries, Ltd.

The content of the rosin compound is 10% by mass or more, 15% by mass or more, 20% by mass or more, 25% by mass or more, or 30% by mass based on the total mass of the polyol and the rosin compound from the viewpoint of improving the initial adhesiveness. It may be% or more. The content of the rosin compound is 65% by mass or less, 60% by mass or less, 55% by mass or less, or 50% by mass or less based on the total mass of the polyol and the rosin compound from the viewpoint of the balance between flexibility and adhesiveness. It may be.

From the viewpoint of further improving the initial adhesiveness, the rosin compound is preferably a compound compatible with the polyol, and more preferably a compound compatible with the polybutadiene polyol and the hydrogenated polybutadiene polyol.

(Urethane prepolymer)
The urethane prepolymer according to the present embodiment can be obtained by reacting a polyol with a polyisocyanate. The urethane prepolymer according to the present embodiment is a reaction product of a polyol and a polyisocyanate, and has a polyurethane chain and an isocyanate group bonded to the end of the polyurethane chain. Urethane prepolymers having isocyanate groups can be cured by reacting with moisture. By containing such a urethane prepolymer, the hot melt adhesive according to the present embodiment can exhibit excellent adhesiveness after moisture curing.

The polyol is not particularly limited, but from the viewpoint of further improving the flexibility of the hot melt adhesive after curing, the polyol may contain at least one selected from the group consisting of polybutadiene polyols and hydrogenated polybutadiene polyols.

The polybutadiene polyol is a compound having a polymer chain derived from butadiene and hydroxyl groups at both ends of the polymer chain, and the hydrogenated polybutadiene polyol is a hydrogenated additive of the polybutadiene polyol. The polybutadiene polyol and the hydrogenated polybutadiene polyol may have an average of about 1.8 to 2.5 hydroxyl groups in the molecule. The polymerized chain derived from polybutadiene and its hydrogenated product can act as an elastomer, and having such a polymerized chain makes it possible to impart adhesiveness and flexibility to the urethane prepolymer. The polyurethane chain of the urethane prepolymer preferably contains a structural unit derived from a hydrogenated polybutadiene polyol because of its superior flexibility.

As the polybutadiene polyol and the hydrogenated polybutadiene polyol, commercially available products can be used as they are. Examples of commercially available hydrogenated polybutadiene polyols include GI-1000, GI-2000, and GI-3000 (trade name manufactured by Nippon Soda Co., Ltd.). Commercially available products of polybutadiene polyols include, for example, G-1000, G-2000, G-3000 (all trade names manufactured by Nippon Soda Co., Ltd.), Poly bd R-15HT, and Poly bd R-45HT (trade name, Idemitsu). Examples include (manufactured by Kosan Co., Ltd.) and Krasol LBH-P3000 (trade name manufactured by Clay Valley Co., Ltd.). These may be used individually by 1 type, and may be used in combination of 2 or more type.

The number average molecular weight (Mn) of the polybutadiene polyol and the hydrogenated polybutadiene polyol may be 500 to 100,000, 700 to 50,000, or 900 to 10000 from the viewpoint of the balance between viscosity and adhesiveness. In the present specification, the number average molecular weight (Mn) is a value measured by gel permeation chromatography (GPC) and converted into standard polystyrene.

The polyol may include a polyol other than the polybutadiene polyol and the hydrogenated polybutadiene polyol (hereinafter, referred to as “other polyol”). Examples of other polyols include polyester polyols, polyether polyols, polyacrylate polyols, polycarbonate polyols, polysiloxane polyols, polyisoprene polyols and polyolefin polyols. As for other polyols, one type may be used alone, or two or more types may be used in combination.

The total content of the polybutadiene polyol and the hydrogenated polybutadiene polyol may be 60% by mass or more, 65% by mass or more, or 70% by mass or more based on the total mass of the polyol from the viewpoint of improving flexibility. The total content of the polybutadiene polyol and the hydrogenated polybutadiene polyol is 100% by mass or less, 95% by mass or less, or 90% by mass or less based on the total mass of the polyol from the viewpoint of the balance between flexibility and adhesiveness. It may be there.

The polyisocyanate is not particularly limited, but the polyisocyanate is preferably a diisocyanate from the viewpoint of handleability during the reaction. Examples of the diisocyanate include aromatic polyisocyanates such as diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate and p-phenylenediisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; dicyclohexylmethane diisocyanate and isophorone diisocyanate. An alicyclic polyisocyanate can be mentioned. One type of polyisocyanate may be used alone, or two or more types may be used in combination. Of these, the polyisocyanate preferably contains diphenylmethane diisocyanate.

The urethane prepolymer according to this embodiment has an isocyanate group. When synthesizing such a urethane prepolymer, the mixing ratio of the polyisocyanate and the polyol is 1.1 or more of the isocyanate group (NCO) equivalent of the polyisocyanate / the hydroxyl group (OH) equivalent of the polyol (NCO equivalent / OH equivalent)). It is preferable to adjust to. The NCO equivalent / OH equivalent may be 1.1 to 2.2, 1.1 to 2.1, or 1.3 to 2.1. When the NCO equivalent / OH equivalent is 1.1 or more, the increase in the viscosity of the obtained urethane prepolymer can be suppressed, and the workability tends to be improved easily. When the NCO equivalent / OH equivalent is 2.2 or less, foaming of the urethane prepolymer during the moisture curing reaction is less likely to occur, and a decrease in adhesiveness tends to be easily suppressed.

The weight average molecular weight (Mw) of the urethane prepolymer may be 1,000,000 to 1,000,000, 50,000 to 500,000, or 100,000 to 300,000. Generally, the weight average molecular weight of urethane prepolymers tends to increase as the NCO equivalent / OH equivalent approaches 1. Further, the higher the Mw of the urethane prepolymer, the higher the viscosity tends to be.

The moisture-curable hot melt adhesive may further contain a catalyst. Examples of the catalyst include dibutyltin dilaurate, dibutyltin octate, dimethylcyclohexylamine, dimethylbenzylamine, trioctylamine, and dimorpholinodiethyl ether. The content of the catalyst is 0.001 to 0.5% by mass, 0.01 to 0.3% by mass, or 0.05 to 0.2% by mass based on the total amount of the moisture-curable hot melt adhesive. It may be there.

The moisture-curable hot melt adhesive may further contain a thermoplastic polymer from the viewpoint of increasing rubber elasticity and imparting stronger adhesiveness. 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 10 to 50% by mass based on the total amount of the moisture-curable hot melt adhesive.

The moisture-curable hot melt adhesive may further contain a tackifier from the viewpoint of imparting stronger adhesiveness. Examples of the tackifier 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 include modified styrene resin, xylene resin, and epoxy resin. The content of the tackifier may be 10 to 50% by mass based on the total amount of the moisture-curable hot melt adhesive. The total content of the thermoplastic polymer and the tackifier may be 10 to 50% by mass based on the total amount of the moisture-curable hot melt adhesive.

Moisture-curable hot melt adhesives include antioxidants, pigments, UV absorbers, surfactants, flame retardants, fillers, photocolorants, thermal color inhibitors, fragrances, imaging agents, thermal crosslinks, as needed. Ingredients such as agents may be further contained.

In the hot melt adhesive according to the present embodiment, a polyol and a polyisocyanate are reacted to form a polyurethane chain containing a structural unit derived from the polyol and a structural unit derived from the polyisocyanate, and an isocyanate group bonded to the end of the polyurethane chain. It can be produced by a method comprising a step of obtaining a urethane prepolymer having.

The hot melt adhesive according to the present embodiment may be prepared by mixing a polyol, a polyisocyanate and a rosin compound to synthesize a urethane prepolymer. Further, the hot melt adhesive according to the present embodiment may be produced by reacting a polyol with a polyisocyanate to obtain a urethane prepolymer and then mixing it with a rosin compound.

The method for producing a hot melt adhesive according to the present embodiment may include a step of reacting a polyol with a polyisocyanate in the presence of a rosin compound to obtain a urethane prepolymer having an isocyanate group, and may also include a step of obtaining a urethane prepolymer having an isocyanate group. It may include a step of reacting with polyisocyanate to obtain a urethane prepolymer having an isocyanate group, and a step of mixing the urethane prepolymer and a rosin compound.

The reaction temperature of the polyol and the polyisocyanate may be, for example, 85 to 120 ° C. The temperature at which the urethane prepolymer and the rosin compound are mixed may be, for example, 85 to 120 ° C.

The viscosity of the moisture-curable hot-melt adhesive (moisture-curable hot-melt adhesive before curing) at 120 ° C. is 0.01 Pa · s or more, 0.05 Pa · s or more, 0.1 Pa · s or more, or 1 Pa · s. It may be s or more, and may be 30 Pa · s or less, 25 Pa · s or less, 20 Pa · s or less, or 15 Pa · s or less. When the viscosity at 120 ° C. is within the above range, the workability (handleability) when the moisture-curable hot melt adhesive is applied to the adherend by a dispenser or the like is improved.

In the moisture-curable hot-melt adhesive, the terminal isocyanate group of the urethane prepolymer contained in the adhesive reacts with the moisture in the air or the moisture on the surface of the adherend. Therefore, for example, a constant temperature bath at 23 ° C. and 50% RH. It can be cured by leaving it for one day.

From the viewpoint of flexibility, the tensile elastic modulus of the moisture-curable hot-melt adhesive after curing may be 0.01 MPa or more, 0.05 MPa or more, or 0.1 MPa or more, 5.5 MPa or less, 5.0 MPa or more. Below, or may be 4.5 MPa or less. When used for clothing, the tensile elastic modulus is within the above range, so that the elasticity is excellent and the feeling of discomfort when worn can be further reduced. In this specification, the tensile elastic modulus after curing means a value measured by the method described in Examples.

The adhesive strength (initial adhesive strength) measured after the adherend is adhered using a moisture-curable hot melt adhesive and before the adhesive is cured is 0.275 N / mm (2.2 N / 8 mm). As mentioned above, it may be 0.300N / mm (2.4N / 8mm) or more, or 0.325N / mm (2.6N / 8mm) or more. In addition, in this specification, the initial adhesive strength means the value measured by the method described in Example.

The moisture-curable 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 die coater, a roll coater, and a spray. When applying to a narrow part such as a small part, a dispenser is suitable.

The adherend is not particularly limited, but may be, for example, cloth or paper. The moisture-curable hot-melt adhesive according to the present embodiment can be suitably used for adhering a plurality of cloths or papers to each other. Here, the object of bonding (adhesion body) may be cloth to cloth, paper to paper, or cloth to paper.

The moisture-curable hot melt adhesive may be formed into a film and used. The moisture-curable hot-melt adhesive film can be formed, for example, by applying a moisture-curable hot-melt adhesive onto a support film such as a PET film. The thickness of the moisture-curable hot melt 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. When the moisture-curable hot-melt adhesive film is thick, the adhesiveness can be ensured, and when the moisture-curable hot-melt adhesive film is thin, the flexibility tends to be more easily secured.

The moisture-curable hot-melt adhesive according to the present embodiment can be bonded with cloth, paper, leather, a resin base material, or the like. The target of bonding may be the same material (for example, cloth and cloth) or different materials (for example, cloth and paper). Such adhesives can be suitably used for apparel products such as clothes, supporters, bags, wallets, interiors, various covers, cases, wearable devices and the like.

[Adhesive]
The adhesive according to one embodiment includes a plurality of cloths and a cured product of the above-mentioned moisture-curable hot melt adhesive that adheres the plurality of cloths to each other. The adhesive body according to this embodiment can be used as, for example, non-sewn clothing.

For the adhesive, for example, the above-mentioned moisture-curable hot-melt adhesive is applied to a cloth to form an adhesive layer, and a cloth, an elastic wiring plate, or the like is further arranged on the adhesive layer and crimped. And the step of obtaining the adhesive precursor and the step of leaving the obtained adhesive precursor in the air (for example, leaving it at 23 ° C. for 1 day) to cure the adhesive layer (moisture-curable hot melt adhesive). It can be manufactured by a method including. In the step of obtaining the adhesive precursor, for example, a pressure roll or the like can be used.

FIG. 1 is a schematic view showing an example of a step of producing an adhesive body according to the present embodiment. With reference to FIG. 1, a process of manufacturing an adhesive using an elastic fabric as the cloth will be described.

First, the stretchable fabric 1 is installed along the jig 10 (see (a) in FIG. 1). Next, the moisture-curable hot-melt adhesive according to the present embodiment is applied to a predetermined portion of the stretchable fabric 1 to form an adhesive layer to be an adhesive portion 4 (see (b) of FIG. 1). The material and shape of the jig 10 are not particularly limited, and can be appropriately selected depending on the intended purpose. The adhesive may be applied using, for example, a dispenser. Next, the elastic fabric 2 is arranged on the adhesive portion 4, and the elastic fabric 1 and the elastic fabric 2 are attached via the adhesive portion 4 while applying pressure from above the elastic fabric 2 by a roll or the like. Together, an adhesive precursor is obtained (see (c) and (d) of FIG. 1). After that, by curing the adhesive precursor, the adhesive portion 4 is moisture-cured, and the adhesive of the stretchable fabric is completed.

In FIG. 1B, the adhesive layer previously formed on the releasable substrate may be transferred onto the elastic fabric 1 to form the adhesive portion 4. Further, the adhesive portion 4 may be provided on the elastic fabric 2 and bonded to the elastic fabric 1. Further, the elastic fabric 2 may be changed to a wiring plate having elasticity to produce an adhesive body between the elastic fabric and the wiring plate.

The adhesive body according to the present embodiment maintains a shape having elasticity even when removed from the jig 10, and can be restored to the original shape after the adhesive body is stretched.

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

The following components were prepared to prepare a moisture-curable hot melt adhesive.
(Polyprethane)
Hydrogenated polybutadiene polyol: Trade name "GI-3000" manufactured by Nippon Soda Co., Ltd. (number of hydroxyl groups: 2, number average molecular weight: 3000)
Rosindiol: Trade name "D-6011" manufactured by Arakawa Chemical Industry Co., Ltd. (hydroxyl value: 117 mgKOH / g, acid value: 0.1 mgKOH / g, softening point: 95 ° C.)
(Polyisocyanate)
Diphenylmethane diisocyanate: Product name "Millionate MT" manufactured by Tosoh Corporation
(Rosin compound without hydroxyl group)
Rosin ester: Product name "KE-311" manufactured by Arakawa Chemical Industry Co., Ltd. (acid value: 5, softening point: 96 ° C)
(catalyst)
Dimorpholino diethyl ether: Product name "UCAT-660M" manufactured by Sun Appro Co., Ltd.

[Moisture-curing hot melt adhesive]
(Examples 1 and 2)
The parts by mass of hydrogenated polybutadiene polyol, diphenylmethane diisocyanate, rosin ester and dimorpholino diethyl ether shown in Table 1 were placed in a reaction vessel and mixed until uniform. The mixture was then reacted at 110 ° C. for 1 hour and then defoamed and stirred at 110 ° C. for 1 hour to prepare a hot melt adhesive containing urethane prepolymer, rosin ester and dimorpholino diethyl ether.

(Comparative Example 1)
A hot melt adhesive containing a urethane prepolymer and dimorpholinodiethyl ether was used in the same manner as in Examples except that the parts of hydrogenated polybutadiene polyol, rosindiol, diphenylmethane diisocyanate and dimorpholinodiethyl ether shown in Table 1 were used. Prepared.

(Comparative Example 2)
A moisture-curable hot-melt adhesive containing a urethane prepolymer and dimorpholinodiethyl ether was prepared in the same manner as in the examples except that the parts of hydride polybutadiene polyol, diphenylmethane diisocyanate and dimorpholinodiethyl ether shown in Table 1 were used. Prepared.

The moisture-curable hot melt adhesive was evaluated under the following conditions. The results are shown in Table 1.

(appearance)
The appearance of the moisture-curable hot melt adhesive after preparation was visually observed. When the adhesive was transparent and had no turbidity, it was judged to be "uniform", and when the adhesive was turbid, it was judged to be "non-uniform".

(viscosity)
The viscosity of the moisture-curable hot melt adhesive was measured using a rheometer (manufactured by AntonioPaar, trade name "MCR-301") under the conditions of frequency 1 Hz, strain swing angle 2%, gap 0.2 mm, and 120 ° C. ..

(Adhesive strength)
A moisture-curable hot-melt adhesive was melted at 120 ° C., applied onto a PET film, and applied to a thickness of 80 μm using a bar coater to form an adhesive layer. The formed adhesive layer was cut out to a width of 8 mm, sandwiched between elastic fabrics having a width of 8 mm (spandex, manufactured by Toray Oplontex Co., Ltd., Lycra (registered trademark)), and a pressure-bonded body was obtained by pressure bonding to the fabric at 120 ° C. .. 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 the initial adhesiveness was evaluated.

(Tensile modulus)
A moisture-curable hot-melt adhesive was melted at 120 ° C., applied onto a PET film, and applied to a thickness of 80 μm using a bar coater to form an adhesive layer. The formed adhesive layer was cured by leaving it in a constant temperature bath at 23 ° C. and 50% RH for 1 day to obtain a cured product of the adhesive layer. The cured product of the obtained adhesive layer was punched to a size of 5 mm × 50 mm, and the PET film was peeled off to prepare a measurement sample. The tensile elastic modulus was measured using a tensile tester (manufactured by Shimadzu Corporation, EZ-Test EZ-SX) under the conditions of a measurement temperature of 25 ° C., a tensile speed of 100 mm / min, and a distance between chucks of 30 mm. It was obtained from the slope of the stress-strain curve at the initial stage of tension.

From the above results, it was confirmed that the moisture-curable hot-melt adhesive of the example had high initial adhesiveness to the cloth and excellent flexibility after curing.

1,2 ... Elastic fabric, 4 ... Adhesive part, 10 ... Jig.

Claims (6)

A polyurethane chain containing a structural unit derived from a polyol and a structural unit derived from polyisocyanate, and a urethane prepolymer having an isocyanate group bonded to the end of the polyurethane chain.
A rosin compound that does not have a hydroxyl group and
Contains a moisture-curable hot melt adhesive. The moisture-curable hot melt adhesive according to claim 1, wherein the polyol contains at least one selected from the group consisting of a polybutadiene polyol and a hydrogenated polybutadiene polyol. The moisture-curable hot-melt adhesive according to claim 2, wherein the polyol contains a hydrogenated polybutadiene polyol. The moisture-curable hot melt adhesive according to any one of claims 1 to 3, wherein the content of the rosin compound is 65% by mass or less based on the total mass of the polyol and the rosin compound. The moisture-curable hot-melt adhesive according to any one of claims 1 to 4, which is used for adhering a plurality of cloths to each other. With multiple cloths
The cured product of the moisture-curable hot-melt adhesive according to any one of claims 1 to 4, which adheres the plurality of cloths to each other.
An adhesive body.

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