JP7246858B2 - THERMOPLASTIC ADHESIVE SHEET AND USE THEREOF - Google Patents

Description

The present invention relates to thermoplastic adhesive sheets and fabrics joined by thermoplastic adhesive sheets.

Various sheet-shaped adhesives are widely used in various industrial fields such as home electric appliances, automobiles, and OA equipment. This type of sheet-like adhesive has well-known advantages such as bonding efficiency and stable quality when compared with other bonding means, and may also have unique advantages in each application. . For example, when compared to stitching a garment, the garment after bonding may be more comfortable to wear. Specifically, in underwear, etc., the sewing thread of the sewn part has skin irritation, whereas the adhesive can join the fabrics while keeping the fabric surface smooth. Does not cause skin irritation. Patent document 1 is cited as a document disclosing a conventional technique used for such applications. Patent Literature 1 proposes a fabric bonding tape in which a pressure-sensitive adhesive layer is arranged on the surface of a hot-melt adhesive in order to obtain temporary adhesiveness. Patent Documents 2 and 3 disclose pressure-sensitive adhesives (hereinafter referred to as "pressure-sensitive Also referred to as "adhesives"), and discloses a pressure-sensitive adhesive containing a styrenic block copolymer.

JP 2008-81724 A JP 2015-28130 A JP 2017-88702 A

Adhesives used for joining the fabrics include thermoplastic adhesives as described in Patent Document 1. Such thermoplastic adhesives are impregnated into the fabrics by hot pressing after being aligned with the fabric joints to join the fabrics together. However, thermoplastic adhesives such as those described above usually do not have tack and do not adhere to rough surfaces such as fabrics at room temperature. Therefore, another means such as the surface adhesive layer used in Patent Document 1 is required for temporary adhesion for positioning and the like. Further, for example, an adhesive impregnated in a stretchable material such as a cloth by heat press does not easily follow the expansion and contraction of the adherend material due to its hardness at room temperature. Therefore, the stretchability of the adherend material can be reduced at the joint with the adhesive. Such a change causes uncomfortable feeling in wearing clothes made of fabric.

The present invention was created in view of the above circumstances, and an object of the present invention is to provide a thermoplastic adhesive sheet that has temporary adhesiveness and deformation recovery, and is capable of exhibiting good adhesive functions. and Another object of the present invention is to provide fabrics bonded by a thermoplastic adhesive sheet.

According to this specification, there is provided a thermoplastic adhesive sheet (hereinafter also simply referred to as "adhesive sheet") having a thermoplastic adhesive (hereinafter also simply referred to as "adhesive") layer. This thermoplastic adhesive sheet has the following properties:
(A) A thermoplastic adhesive sheet is attached to a polyester urethane foam having a thickness of 10 mm in an environment of 23° C. and 50% RH by reciprocating a 2 kg roller once, left in the same environment for 30 minutes, and then stretched. The peel strength measured under conditions of 300 mm/min and a peel angle of 180 degrees is 2 N/10 mm or more; and (B) A thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm is prepared, and the measurement sample is After being stretched 50% at a speed of 300 mm / min at 23 ° C. and held for 3 seconds, when contracted at a speed of 300 mm / min, the contraction strength F S30 _{% against the elongation strength F E30%} at _30% elongation length. The hysteresis obtained from the ratio [F _S30% /F _E30% ] is 35% or more;
satisfy.

According to the above configuration, by satisfying the characteristic (A), the adhesive sheet has tack at room temperature (about 23 ° C.), and for example, it can be temporarily adhered to rough surfaces such as fabrics by hand at room temperature. show gender. The adhesive sheet bonded to the adherend material by temporary adhesion is then bonded to the adherend with high positional accuracy by subsequent adhesion (also referred to as "final adhesion") by hot press or the like. In this adhesion, good adhesive fixation is achieved by utilizing the thermoplastic properties of the thermoplastic adhesive sheet. In particular, when the surface of the adherend is rough or the adherend is a material to be impregnated, the adhesive sheet spreads by heating or penetrates into the adherend to exhibit good adhesion performance. obtain. Here, the material to be impregnated means a material having a property of allowing impregnation of a fluid (typically liquid). Further, by satisfying the characteristic (B), the adhesive sheet deforms as the material deforms (e.g., expands and contracts) in an embodiment in which the adhesive sheet is attached to a material having deformation recovery properties, such as a stretchable material or a rubber elastic material. After that, it can recover its original shape together with the adherend material. In other words, the adhesive sheet does not interfere with the shape recovery (eg stretchability) of the adherend material. Such deformation recovery properties that can follow the deformation recovery (e.g., stretchability) of the adherend may not impair the wearing comfort of clothes (particularly underwear), for example. In short, a thermoplastic adhesive sheet that satisfies the above properties can exhibit a good adhesive function while having both temporary adhesiveness and deformation recovery.

A thermoplastic adhesive sheet according to a preferred embodiment has the following properties:
(C) A 30% modulus measured at a speed of 300 mm/min at 23°C for a thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm is 0.6 MPa or less;
further satisfied.
Since the adhesive sheet satisfying the property (C) is excellent in flexibility, it does not impair the flexibility of the material when used for adhesion of materials having flexibility such as cloth. For example, when the adhesive sheet is used in a mode of impregnating an adherend material, it is advantageous to be able to ensure flexibility within the material. One example of the effect of this configuration is a reduction in the hardness (strength) of conventional adhesives applied to fabrics.

A thermoplastic adhesive sheet according to a preferred embodiment has the following properties:
(D) The thermoplastic adhesive sheet was pressed against a stainless steel plate under the conditions of 120°C, 0.2 MPa, and 10 seconds, left at 23°C for 30 minutes, and then measured under the conditions of a tensile speed of 300 mm/min and a peeling angle of 180 degrees. The peel strength is 15 N / 10 mm or more;
further satisfied.
A thermoplastic adhesive sheet that satisfies the above property (D) can be strongly adhered to an adherend having a rough surface such as a fabric by thermocompression bonding, and therefore has excellent adhesion reliability.

In a preferred embodiment, the thermoplastic adhesive layer is a rubber-based adhesive layer containing a rubber-based polymer as a base polymer. Further, the thermoplastic adhesive layer more preferably contains a block copolymer of a monovinyl-substituted aromatic compound and a conjugated diene compound as a base polymer. By employing the above rubber-based adhesive, the properties and effects disclosed herein can be preferably achieved.

In a preferred embodiment, the thermoplastic adhesive layer contains, as a tackifying resin, a tackifying resin T _LOH having a hydroxyl value of 30 mgKOH/g or less. Degradation of the adhesive sheet is preferably suppressed by using a tackifying resin having a hydroxyl value of a predetermined value or less.

In one preferred embodiment, the thermoplastic adhesive layer is a non-crosslinkable adhesive layer. A non-crosslinkable adhesive tends to provide good adhesive strength by thermocompression bonding.

In a preferred embodiment, the thermoplastic adhesive sheet has a thickness of 0.03 mm to 1 mm. Temporary adhesion and final adhesion tend to be improved by setting the thickness of the adhesive sheet to a predetermined value or more. Further, by setting the thickness to a predetermined value or less, the deformation recovery property of the adherend material is likely to be maintained.

A thermoplastic adhesive sheet according to a preferred embodiment is configured as a substrate-less adhesive sheet consisting only of an adhesive layer. By configuring in this way, each of the above characteristics can be preferably satisfied, and the effects of the technology disclosed herein can be preferably exhibited. In addition, the bonding of the adherends can be completed using only the thermoplastic adhesive without using a base material. This is significant in terms of productivity, bonding efficiency, weight reduction, and the like of the adhesive sheet.

Since the thermoplastic adhesive sheet disclosed herein has temporary adhesiveness and can exhibit a good adhesive function, it is preferably used for joining cloths that require alignment by temporary adhesion. In addition, the adhesive sheet is excellent in deformation recovery. Therefore, it is preferable for use in joining elastic fabrics (preferably underwear). By applying the technology disclosed herein to the bonding of fabrics, the adhesive sheet is accurately aligned with the bonded portion of the fabric using its temporary adhesiveness, and then the adhesive sheet is impregnated into the fabric by the final bonding by heating. As a result, it exhibits good adhesive strength and follows the elasticity of the fabric well. This leads, for example, to not impairing the wearing comfort of clothes made using the fabric. Therefore, according to the technology disclosed herein, there is provided a fabric bonded by any of the thermoplastic adhesive sheets disclosed herein.
In this specification, the joining of fabrics may be joining one fabric to another fabric, or joining one part of one fabric to another part.

1 is a schematic cross-sectional view showing the structure of a thermoplastic adhesive sheet (base-less double-sided adhesive sheet) according to one embodiment. FIG. FIG. 3 is a schematic cross-sectional view showing the configuration of a thermoplastic adhesive sheet (double-sided adhesive sheet with a substrate) according to another embodiment. FIG. 4 is a schematic cross-sectional view showing the configuration of a thermoplastic adhesive sheet (single-sided adhesive sheet with base material) according to another embodiment.

Preferred embodiments of the present invention are described below. Matters other than those specifically mentioned in this specification, which are necessary for carrying out the present invention, can be grasped as design matters by those skilled in the art based on the prior art in the relevant field. The present invention can be implemented based on the contents disclosed in this specification and common general technical knowledge in the field.
In the drawings below, members and portions having the same function are denoted by the same reference numerals, and redundant description may be omitted or simplified. In addition, the embodiments described in the drawings are schematic for clearly explaining the present invention, and do not accurately represent the size and scale of the adhesive sheet of the present invention that is actually provided as a product.

In this specification, the term "thermoplastic adhesive" refers to an adhesive that softens and plastically deforms when heated to a predetermined temperature or higher. A thermoplastic adhesive is a material that hardens again when it is cooled to below its melting temperature, and has the property of repeating softening and hardening reversibly by heat. The thermoplastic adhesives disclosed herein can be flowable at temperatures of about 80° C. or higher (eg, about 100° C. or higher, typically about 120° C. or higher). Thermoplastic properties are usually controlled by appropriately setting the conditions (temperature, pressure, time, etc.) during the actual bonding. In a typical embodiment, the thermoplastic adhesive has a weight fraction (gel fraction) of organic solvent-insoluble matter measured by immersing it in an organic solvent such as toluene for one week, and is about 3% or less (e.g., 0 ~1%). The gel fraction is measured using a porous polytetrafluoroethylene membrane (for example, trade name "Nitoflon NTF1122" manufactured by Nitto Denko, average pore diameter 0.2 µm, porosity 75%).

In this specification, the "pressure-sensitive adhesive" is, as described above, a material that exhibits a soft solid (viscoelastic) state in a temperature range around room temperature and that has the property of easily adhering to an adherend under pressure. Say. The pressure-sensitive adhesive referred to herein generally has a complex tensile modulus E ^* ( 1 Hz)<10 ⁷ dyne/cm ² (typically, the material has the above properties at 25° C.). The pressure sensitive adhesive in the technology disclosed herein can also be understood as a solid content of the adhesive composition or as a component of the adhesive layer. In the technology disclosed herein, adhesives and adhesive layers that satisfy property (A) described later are typical examples of the pressure-sensitive adhesives and pressure-sensitive adhesive layers.

The term "block copolymer of a monovinyl-substituted aromatic compound and a conjugated diene compound" as used herein means a monovinyl-substituted aromatic compound as a main monomer (refers to a copolymer component exceeding 50% by weight; hereinafter the same.) A polymer having at least one segment (hereinafter also referred to as "A segment") and a segment (hereinafter also referred to as "B segment") having a conjugated diene compound as the main monomer. Generally, the glass transition temperature of the A segment is higher than that of the B segment. Typical structures of such polymers include a copolymer having a triblock structure (ABA structure triblock) having A segments (hard segments) at both ends of a B segment (soft segment), one A A copolymer having a diblock structure consisting of a segment and one B segment (a diblock having an AB structure) and the like can be mentioned.

Further, the term "styrenic block copolymer" as used herein means a polymer having at least one styrene block. The styrene block refers to a segment containing styrene as the main monomer. A segment consisting essentially of styrene is a typical example of a styrene block as used herein. A "styrene-isoprene block copolymer" refers to a polymer having at least one styrene block and at least one isoprene block (a segment containing isoprene as a main monomer). A representative example of a styrene isoprene block copolymer is a triblock structure copolymer (triblock) having styrene blocks (hard segments) at both ends of an isoprene block (soft segment), one isoprene block and one styrene and a copolymer having a diblock structure consisting of blocks (diblocks). "Styrene-butadiene block copolymer" refers to a polymer having at least one styrene block and at least one butadiene block (segment with butadiene as the main monomer).

Further, in the present specification, the "styrene content" of a styrenic block copolymer refers to the weight ratio of the styrene component to the total weight of the block copolymer. The styrene content can be measured by NMR (nuclear magnetic resonance spectroscopy).
The ratio of diblocks in the styrenic block copolymer (hereinafter sometimes referred to as "diblock ratio" or "diblock ratio") is obtained by the following method. That is, a styrenic block copolymer is dissolved in tetrahydrofuran (THF), GS5000H and G4000H columns for liquid chromatography (manufactured by Tosoh Corporation) are connected in series, with a total of four stages each being connected in series, and THF is used as the mobile phase. High performance liquid chromatography is performed under the conditions of a temperature of 40° C. and a flow rate of 1 mL/min. The peak area corresponding to the diblock is measured from the obtained chart. Then, by calculating the percentage of the peak area corresponding to the diblock relative to the total peak area, the diblock ratio is determined.

<Structure example of thermoplastic adhesive sheet>
The adhesive sheet disclosed herein (which can be in a long form such as a tape) is, for example, a substrate-less (that is, having no substrate) double-sided adhesive sheet 1 as shown in FIG. can be in the form This adhesive sheet 1 is a baseless adhesive sheet comprising a thermoplastic adhesive layer 11 . The adhesive layer 11 typically has a single layer structure. In the double-sided adhesive sheet 1 before use (before attachment to an adherend), the first adhesive surface 11A and the second adhesive surface 11B of the adhesive layer 11 are peeled off, and at least the surface (front surface) on the adhesive layer side is peeled off. It may be in a form protected by release liners 21 and 22, respectively, which are planar. Alternatively, the release liner 22 may be omitted, and a release liner 21 having release surfaces on both sides may be used. It may be in a form in which it abuts against the back surface of 21 and is protected.

The technique disclosed herein is preferably applied to a substrate-less double-sided adhesive sheet as shown in FIG. 1, and can also be applied to a substrate-attached double-sided adhesive sheet 2 as shown in FIG. This double-sided adhesive sheet 2 comprises a substrate (for example, a polyurethane film) 15, and a first adhesive layer 11 and a second adhesive layer 12 supported on both sides of the substrate 15, respectively. More specifically, the first adhesive layer 11 and the second adhesive layer 12 are provided on the first surface 15A and the second surface 15B (both of which are non-releasable) of the substrate 15, respectively.

The technology disclosed herein also uses a single-sided adhesive type substrate comprising a substrate 15 and an adhesive layer 11 supported on a first surface (non-release surface) 15A of the substrate, as shown in FIG. It can also be applied to the attached adhesive sheet 3. The adhesive sheet 3 before use is, for example, as shown in FIG. 21 protected form. Alternatively, by omitting the release liner 21 and using the substrate 15 whose second surface 15B is the release surface, the adhesive sheet 3 with the substrate is wound so that the first adhesive surface 11A of the substrate 15 becomes the second adhesive surface. It may be in a form protected by abutting against the surface 15B.

The total thickness of the adhesive sheet disclosed herein is not particularly limited, and from the viewpoint of thinning, miniaturization, weight saving, resource saving, etc., it is suitable to be approximately 3 mm or less, preferably approximately 1 mm. Below, more preferably about 0.7 mm or less, still more preferably about 0.5 mm or less (for example, about 0.4 mm or less). An adhesive layer with a limited thickness limits the amount of impregnation into an adherend such as a fabric during thermocompression bonding, so the impregnation affects the deformation recovery (e.g., stretchability) of the adherend. tend to be small. From the viewpoint of ensuring good adhesive properties, the total thickness is suitably about 0.01 mm or more, preferably about 0.03 mm or more, more preferably about 0.05 mm or more. More preferably, it is about 0.1 mm or more. The total thickness of the adhesive sheet includes the thickness of the adhesive layer and the substrate, but does not include the thickness of the release liner.

<Characteristics of Thermoplastic Adhesive Sheet>
(Characteristic (A))
The adhesive sheet disclosed herein is characterized by an adhesive strength to foam (adhesive strength to foam) of approximately 2 N/10 mm or more. Since the surface of the foam is a rough surface, the adhesive sheet satisfying the above properties exhibits good temporary adhesiveness to a rough surface such as a fabric when manually applied at room temperature. This enables accurate positioning with respect to the surface of the adherend. The adhesion to foam is preferably about 3 N/10 mm or more, more preferably about 4 N/10 mm or more. The adhesive strength to the foam may be about 5 N/10 mm or more, but from the viewpoint of re-sticking properties, etc., it is suitable to be about 10 N/10 mm or less, preferably about 8 N/10 mm or less (for example, about 6 N/10 mm or less).

The property (A) (adhesive strength to foam) is specifically measured by the following method. That is, the thermoplastic adhesive sheet is cut into a size of 100 mm×10 mm to prepare a measurement sample. When the measurement target is a double-sided adhesive sheet, one side (non-measurement adhesive side) is attached to a polyethylene terephthalate (PET) film having a thickness of 25 μm for backing. Next, in an environment of 23° C. and 50% RH, the surface of the thermoplastic adhesive layer to be measured is exposed, and the exposed adhesive surface is applied to the surface of a polyester urethane foam having a thickness of 10 mm as an adherend. The rollers are reciprocated once to bond them together (pressure bonding). After leaving this in the same environment for 30 minutes, using a universal tensile compression tester, the peel strength (adhesive strength to foam) [N / 10 mm] was measured under the conditions of a tensile speed of 300 mm / min and a peel angle of 180 degrees. Measure. As the adherend, polyester soft urethane foam (trade name “SC” (gray) manufactured by INOAC Corporation, density 31 kg/m ³ ) is used. In addition, as a universal tension/compression tester, a commercially available device (for example, Minebea Co., Ltd. device name “Tension/compression tester, TG-1kN”) can be used. It is measured by the same method in the examples described later.

(Characteristic (B))
Further, the adhesive sheet disclosed herein is characterized by a hysteresis (30% hysteresis at 50% elongation) measured by the following method of about 35% or more. By satisfying this property, for example, in a mode in which the adhesive sheet is attached to a deformation-recovery material such as a stretchable material, the adhesive sheet deforms as the material deforms (e.g., stretches), and then returns to its original state together with the adherend material. It can regain its shape. In other words, the adhesive sheet does not interfere with the shape recovery (eg stretchability) of the adherend material. The 30% hysteresis at 50% elongation is preferably about 40% or more, more preferably about 50% or more (for example, 55% or more). The hysteresis is ideally 100%, but may be about 80% or less, for example, about 70% or less, from the viewpoint of compatibility with other properties such as temporary adhesiveness.

The characteristic (B) (30% hysteresis at 50% elongation) is specifically measured by the following method. That is, a thermoplastic adhesive sheet is cut into a width of 50 mm so as to have a measurement length of 100 mm, and is wound in the width direction to form a cylindrical measurement sample. Although this measurement depends on the length of the measurement sample, it does not depend on the cross-sectional area (that is, thickness and width), so widths other than 50 mm may be adopted as long as the measurement is not hindered. For the same reason, there is no need to wind or form a cylinder if it does not interfere with measurement. The prepared measurement sample is set in a tensile compression tester so that the distance between chucks (measurement length) is 100 mm, and is stretched by 50% at a speed of 300 mm / min at 23 ° C. (thus, stretched to 150 mm). After holding for 3 seconds in the state of 100% elongation, contraction is performed at a rate of 300 mm/min to return to 0% elongation (distance between chucks: 100 mm). In this measurement, the elongation strength F _E30% [N] at 30% elongation length (130 mm) and the contraction strength F _S30% [N] at 30% elongation length are recorded, and the elongation strength F _E30% [N] The hysteresis value (%) is obtained from the following formula from the ratio of shrinkage strength F _S30% to F _S30% /F _E30% ].
Hysteresis value (%) = _FS30% / _FE30% x 100
As a universal tension/compression tester, a commercially available device (for example, Minebea Co., Ltd. device name “Tension/compression tester, TG-1kN”) can be used. It is measured by the same method in the examples described later.

(Characteristic (C))
An adhesive sheet according to a preferred embodiment has a 30% modulus of 0.6 MPa or less. When the object to which the adhesive sheet is to be adhered is a flexible material such as cloth, for example, by using an adhesive sheet that satisfies the above properties, adhesion is achieved that does not hinder the deformation of the material and does not impair the flexibility. be. The 30% modulus is more preferably approximately 0.5 MPa or less, and still more preferably approximately 0.45 MPa or less (for example, 0.4 MPa or less). From the viewpoint of compatibility with other properties such as deformation recovery, the 30% modulus is usually about 0.1 MPa or more, preferably about 0.2 MPa or more, and more preferably about 0.3 MPa. or more (for example, 0.35 MPa or more).

Property (C) (30% modulus) is measured at a speed of 300 mm/min at 23° C. on a thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm. Specifically, in the measurement of the above characteristic (B), the elongation strength F _E30% [N] at a 30% elongation length (130 mm) is divided by the cross-sectional area [mm ² ] of the adhesive sheet, resulting in a 30% modulus [MPa] can be obtained. Since the 30% modulus does not depend on the length of the sample to be measured, the distance between the chucks of the tension/compression tester may be appropriately changed during measurement. Moreover, since it is divided by the cross-sectional area, the width and thickness can also be changed within a range that does not interfere with the measurement. For the same reason, it is not necessary to wind or form a cylinder as long as it does not interfere with the measurement. Other measurement conditions are basically the same as those for the characteristic (B) measurement. It is measured by the same method in the examples described later.

(Characteristic (D))
The adhesive sheet according to a preferred embodiment has a thermocompression adhesion strength to stainless steel (a thermocompression adhesion strength to SUS) of about 15 N/10 mm or more measured under thermocompression conditions of 120° C., 0.2 MPa, and 10 seconds. The thermocompression bonding strength to SUS shows a high correlation with the thermocompression bonding strength to rough surfaces such as fabrics, although the absolute values are different. A thermoplastic adhesive sheet that satisfies this property tends to exhibit a predetermined or higher thermocompression bonding strength even to rough surfaces such as fabrics. can be strongly adhered to. The thermocompression bonding strength to SUS is more preferably about 18 N/10 mm or more, more preferably about 20 N/10 mm or more, particularly preferably about 22 N/10 mm or more, for example about 25 N/10 mm or more, It may be about 28 N/10 mm or more, or about 30 N/10 mm or more. The upper limit of the thermocompression bonding strength to SUS is not particularly limited, and may be, for example, approximately 50 N/10 mm or less.

The property (D) (thermocompression bonding strength to SUS) is specifically measured by the following method. That is, the thermoplastic adhesive sheet is cut into a size of 100 mm×10 mm to prepare a measurement sample. When the object to be measured is a double-sided adhesive sheet, one side (non-measured adhesive side) is adhered to a PET film having a thickness of 50 μm for backing. Next, in an environment of 23° C. and 50% RH, the surface of the thermoplastic adhesive layer to be measured is exposed, and the exposed adhesive surface is applied to the surface of a stainless steel plate (SUS304 plate) as an adherend at 120° C. Thermocompression bonding is performed under the conditions of 0.2 MPa and 10 seconds. After leaving this in the same environment for 30 minutes, using a universal tensile compression tester, under the conditions of a tensile speed of 300 mm / min and a peel angle of 180 degrees, peel strength (thermocompression bonding strength to SUS) [N / 10 mm ] is measured. As a universal tension/compression tester, a commercially available device (for example, Minebea Co., Ltd. device name “Tension/compression tester, TG-1kN”) can be used. It is measured by the same method in the examples described later.

<Thermoplastic adhesive layer>

The type of adhesive that constitutes the thermoplastic adhesive layer disclosed herein is not particularly limited. The adhesive layer includes, for example, acrylic, polyester, urethane, polyether, olefin, rubber, silicone, polyamide, fluorine, vinyl acetate, vinyl chloride, vinyl alcohol, and vinyl acetal. Adhesive composition containing, as a base polymer (the main component of the polymer component, that is, a component accounting for 50% by weight or more) selected from various polymers (adhesive polymers) such as vinyl butyral-based polymers (adhesive polymers) It can be an adhesive layer formed from a material. The technology disclosed herein can be preferably implemented in the form of an adhesive sheet having an adhesive layer containing, for example, acrylic polymer, polyester polymer, urethane polymer, or rubber polymer as a base polymer. Among others, the form of an adhesive sheet having a rubber-based adhesive layer containing a rubber-based polymer as a base polymer is particularly preferred.

Examples of the base polymer contained in the rubber-based adhesive layer include natural rubber; styrene-butadiene rubber; polyisoprene; acrylonitrile-butadiene rubber; chloroprene rubber; ) and/or 2-methylpropene (isobutylene) as a main monomer; AB type or ABA type block copolymer rubbers and hydrogenated products thereof, such as styrene-butadiene-styrene block Copolymer rubber (SBS), styrene-isoprene-styrene block copolymer rubber (SIS), hydrogenated SBS styrene-ethylene-butylene-styrene block copolymer rubber, styrene-ethylene hydrogenated SIS -Propylene-styrene block copolymer rubber; These rubber-based polymers can be used singly or in combination of two or more.

<Base polymer>
An adhesive layer according to a preferred embodiment contains a block copolymer of a monovinyl-substituted aromatic compound and a conjugated diene compound as a base polymer. The monovinyl-substituted aromatic compound refers to a compound in which one functional group having a vinyl group is bonded to an aromatic ring. A representative example of the aromatic ring is a benzene ring (which may be a benzene ring substituted with a functional group (for example, an alkyl group) having no vinyl group). Specific examples of the monovinyl-substituted aromatic compounds include styrene, α-methylstyrene, vinyltoluene, vinylxylene and the like. Specific examples of the conjugated diene compound include 1,3-butadiene and isoprene. Such block copolymers can be used for the base polymer singly or in combination of two or more.

The A segment (hard segment) in the block copolymer has a copolymerization ratio of about 70% by weight or more (more preferably about 90% by weight or more) of the monovinyl-substituted aromatic compound (two or more kinds can be used in combination). and may be substantially 100% by weight). The B segment (soft segment) in the block copolymer has a copolymerization ratio of about 70% by weight or more (more preferably about 90% by weight or more) of the conjugated diene compound (two or more kinds may be used in combination), may be substantially 100% by weight). Such a block copolymer can realize an adhesive sheet with higher performance.

The block copolymers can be in the form of diblocks, triblocks, radials, mixtures thereof, and the like. In a triblock body or a radial body, it is preferable that an A segment (for example, a styrene block) is arranged at the end of the polymer chain. This is because the A segments arranged at the end of the polymer chain tend to gather together to form a domain, thereby forming a pseudo-crosslinked structure and improving the cohesiveness of the adhesive.
As the block copolymer in the technique disclosed herein, it is appropriate to use one having a diblock ratio of about 30% by weight or more from the viewpoint of adhesive strength (peel strength) to the adherend. The proportion of block bodies is preferably approximately 40% by weight or more, more preferably approximately 50% by weight or more, still more preferably approximately 60% by weight or more, and particularly preferably approximately 65% by weight or more. From the viewpoint of peel strength, a block copolymer having a diblock ratio of about 70% by weight or more is most preferable. From the viewpoint of cohesiveness and the like, a block copolymer having a diblock ratio of about 90% by weight or less (more preferably about 85% by weight or less, for example about 80% by weight or less) can be preferably used.

<Styrene block copolymer>
In a preferred aspect of the technology disclosed herein, the base polymer is a styrenic block copolymer. For example, it is preferable that the base polymer contains at least one of a styrene-isoprene block copolymer and a styrene-butadiene block copolymer. Among the styrene block copolymers contained in the adhesive, the proportion of the styrene isoprene block copolymer is approximately 70% by weight or more, or the proportion of the styrene butadiene block copolymer is approximately 70% by weight or more, or It is preferable that the total proportion of the styrene-isoprene block copolymer and the styrene-butadiene block copolymer is approximately 70% by weight or more. In one preferred embodiment, substantially all of the styrenic block copolymer (eg, about 95-100% by weight) is a styrene isoprene block copolymer.

The styrene content of the styrenic block copolymer can be, for example, approximately 5 to 40% by weight. From the viewpoint of cohesiveness, styrenic block copolymers having a styrene content of about 10% by weight or more (more preferably more than 10% by weight, for example 12% by weight or more) are preferred. From the viewpoint of peel strength, the styrene content is preferably about 35% by weight or less (typically about 30% by weight or less, more preferably about 25% by weight or less), and about 20% by weight or less (typically less than 20% by weight, such as 18% by weight or less) are particularly preferred. From the viewpoint of better exhibiting the effect of applying the technology disclosed herein (for example, the effect of improving temporary adhesion), a styrene block copolymer having a styrene content of 12% by weight or more and less than 20% by weight can be preferably employed.

In the technology disclosed herein, when a block copolymer (for example, a styrene-based block copolymer) of a monovinyl-substituted aromatic compound and a conjugated diene compound is used as the base polymer, a rubber-like polymer other than the block copolymer may contain one or more. Such rubber-like polymers include acrylic, polyester, urethane, polyether, olefin, rubber, silicone, polyamide, fluorine, vinyl acetate, vinyl chloride, and vinyl polymers known in the field of adhesives. Various polymers such as alcohol-based, vinyl acetal-based, and vinyl butyral-based polymers can be used. Examples of the rubbery polymer include natural rubber, acrylonitrile-butadiene rubber, isoprene rubber, chloroprene rubber, polyisobutylene, butyl rubber, and recycled rubber. When the adhesive layer contains a rubber-like polymer other than the block copolymer, the amount of the rubber-like polymer used is usually about 50 parts by weight or less per 100 parts by weight of the block copolymer. , preferably about 30 parts by weight or less, more preferably about 10 parts by weight or less (for example, about 5 parts by weight or less). The technique disclosed herein is an aspect in which the adhesive layer does not substantially contain a rubber-like polymer other than the block copolymer (for example, the content per 100 parts by weight of the block copolymer is 0 to 1 weight part). part).

<Tackifying resin>
The adhesive layers disclosed herein preferably contain a tackifying resin in addition to the base polymer described above. The tackifier resin is selected from various known tackifier resins such as petroleum resins, styrene resins, coumarone-indene resins, terpene resins, modified terpene resins, rosin resins, rosin derivative resins, and ketone resins. A species or two or more species can be used.

Examples of petroleum resins include aliphatic (C5) petroleum resins, aromatic (C9) petroleum resins, aliphatic/aromatic copolymer (C5/C9) petroleum resins, hydrogenated products thereof ( For example, alicyclic petroleum resin obtained by hydrogenating aromatic petroleum resin) and the like.

Examples of styrene resins include those mainly composed of styrene homopolymers, those mainly composed of α-methylstyrene homopolymers, those mainly composed of vinyltoluene homopolymers, styrene, Those whose main component is a copolymer containing two or more of α-methylstyrene and vinyltoluene in the monomer composition (for example, α-methylstyrene/styrene copolymer whose main component is α-methylstyrene/styrene copolymer polymer resin) and the like.

As the coumarone-indene resin, a resin containing coumarone and indene as monomer components constituting the skeleton (main chain) of the resin can be used. Examples of monomer components other than coumarone and indene that can be contained in the resin skeleton include styrene, α-methylstyrene, methylindene, and vinyltoluene.

Examples of terpene resins include α-pinene polymer, β-pinene polymer, dipentene polymer and the like. Examples of modified terpene resins include those obtained by modifying the above terpene resins (phenol modification, styrene modification, hydrogenation modification, hydrocarbon modification, etc.). Specific examples include terpene phenol resins, styrene-modified terpene resins, and hydrogenated terpene resins.

The above-mentioned "terpene phenol resin" refers to a polymer containing a terpene residue and a phenol residue, and is a copolymer of a terpene and a phenol compound (terpene-phenol copolymer resin) and a terpene homopolymer or copolymer. It is a concept that includes both coalescence (terpene resin, typically unmodified terpene resin) and phenol-modified one (phenol-modified terpene resin). Preferable examples of the terpene constituting the terpene phenol resin include monoterpenes such as α-pinene, β-pinene, and limonene (including d-, l- and d/l-forms (dipentene)).

Specific examples of rosin-based resins include unmodified rosins (fresh rosins) such as gum rosin, wood rosin, and tall oil rosin; rosin, disproportionated rosin, polymerized rosin, other chemically modified rosins, etc.); Examples of rosin derivative resins include those obtained by esterifying unmodified rosin with alcohols (that is, esterified rosin), and modified rosins (hydrogenated rosin, disproportionated rosin, polymerized rosin, etc.) with alcohols. Rosin esters such as esterified products (that is, esterified products of modified rosin); Unmodified rosin or modified rosin (hydrogenated rosin, disproportionated rosin, polymerized rosin, etc.) modified with unsaturated fatty acid Rosins; unsaturated fatty acid-modified rosin esters obtained by modifying rosin esters with unsaturated fatty acids; unmodified rosin, modified rosin (hydrogenated rosin, disproportionated rosin, polymerized rosin, etc.), Rosin alcohols obtained by reducing the carboxyl groups in saturated fatty acid-modified rosin esters; metal salts of rosins (especially rosin esters) such as unmodified rosin, modified rosin, and various rosin derivatives; rosins (unmodified rosin, modified rosin, various rosin derivatives, etc.), and the like.

<Tackifying resin T _LOH >
In one preferred embodiment of the technology disclosed herein, the adhesive layer may contain a tackifier resin T _LOH having a hydroxyl value of approximately 30 mgKOH/g or less. Degradation of the adhesive sheet is preferably suppressed by using a tackifying resin having a hydroxyl value of a predetermined value or less. Tackifying resin T _LOH can be used individually by 1 type or in combination of 2 or more types. The hydroxyl value of the tackifying resin T _LOH is preferably less than about 20 mg KOH/g, more preferably less than about 15 mg KOH/g, even more preferably less than about 10 mg KOH/g, particularly preferably less than about 5 mg KOH/g, such as less than 3 mg KOH/g. ). For example, a tackifying resin T _LOH having a hydroxyl value of less than 1 mgKOH/g or having no detectable hydroxyl group can be preferably used.

Here, as the value of the hydroxyl value, a value measured by a potentiometric titration method specified in JIS K0070:1992 can be adopted. A specific measuring method is as follows.
[Method for measuring hydroxyl value]
1. Reagent (1) As the acetylation reagent, approximately 12.5 g (approximately 11.8 mL) of acetic anhydride is taken, pyridine is added to bring the total amount to 50 mL, and the mixture is thoroughly stirred and used. Alternatively, take about 25 g (about 23.5 mL) of acetic anhydride, add pyridine to bring the total amount to 100 mL, and use the mixture after thorough stirring.
(2) A 0.5 mol/L potassium hydroxide ethanol solution is used as a measurement reagent.
(3) In addition, prepare toluene, pyridine, ethanol and distilled water.
2. Operation (1) About 2 g of a sample is accurately weighed and collected in a flat-bottomed flask, 5 mL of an acetylation reagent and 10 mL of pyridine are added, and an air cooling tube is attached.
(2) After heating the flask in a bath at 100°C for 70 minutes, allowing it to cool, adding 35 mL of toluene as a solvent from the top of the cooling tube and stirring, then adding 1 mL of distilled water and stirring to obtain acetic anhydride. decompose. Heat again in the bath for 10 minutes for complete decomposition and allow to cool.
(3) Wash the cooling tube with 5 mL of ethanol and remove. Then, 50 mL of pyridine is added as a solvent and stirred.
(4) Add 25 mL of 0.5 mol/L potassium hydroxide ethanol solution using a whole pipette.
(5) Perform potentiometric titration with 0.5 mol/L potassium hydroxide ethanol solution. The inflection point of the obtained titration curve is taken as the end point.
(6) In the blank test, the above (1) to (5) are performed without any sample.
3. Calculation Calculate the hydroxyl value by the following formula.
Hydroxyl value (mgKOH/g) = [(BC) x f x 28.05]/S + D
here,
B: Amount (mL) of 0.5 mol/L potassium hydroxide ethanol solution used in the blank test,
C: Amount (mL) of 0.5 mol/L potassium hydroxide ethanol solution used for the sample,
f: factor of 0.5 mol/L potassium hydroxide ethanol solution,
S: weight of sample (g),
D: acid value,
28.05: ½ of the molecular weight of potassium hydroxide, 56.11;
is.

An adhesive layer according to a preferred embodiment contains a tackifier resin T _LOH1 having a softening point of 120° C. or higher as the tackifier resin T _LOH . From the viewpoint of high-temperature cohesiveness and adhesion reliability (adhesion reliability after main adhesion by hot press or the like), the softening point of the tackifying resin _TLOH1 is more preferably about 130° C. or higher, more preferably about 140° C. or higher. Particularly preferably, it is approximately 145° C. or higher (eg, 150° C. or higher). From the viewpoint of peel strength to adherends, etc., the softening point of the tackifier resin T _LOH1 is usually about 200° C. or less, preferably about 180° C. or less, more preferably about 170° C. or less (e.g., 160° C. below).

The softening point of the tackifier resin referred to here is defined as a value measured based on the softening point test method (ring and ball method) specified in JIS K5902 and JIS K2207. Specifically, the sample is melted as quickly as possible at the lowest possible temperature and carefully filled into a ring placed on a flat metal plate to avoid the formation of bubbles. After cooling, cut off the raised portion from the plane containing the top of the ring with a slightly heated knife. Next, a supporter (ring stand) is placed in a glass container (heating bath) having a diameter of 85 mm or more and a height of 127 mm or more, and glycerin is poured to a depth of 90 mm or more. Next, the steel ball (diameter 9.5 mm, weight 3.5 g) and the ring filled with the sample are immersed in the glycerin without touching each other, and the temperature of the glycerin is maintained at 20°C plus or minus 5°C for 15 minutes. . A steel ball is then centered on the surface of the sample in the ring and placed in position on the support. Next, the distance from the top end of the ring to the glycerin surface is kept at 50 mm, a thermometer is placed, the center of the mercury ball of the thermometer is set at the same height as the center of the ring, and the container is heated. The Bunsen burner flame used for heating is directed halfway between the center and the rim of the bottom of the vessel to ensure even heating. The rate at which the bath temperature rises after reaching 40° C. from the start of heating must be 5.0±0.5° C. per minute. The temperature at which the sample gradually softens and flows down the ring and finally touches the bottom plate is read and taken as the softening point. Two or more softening points are measured at the same time, and the average value is adopted.

As the tackifying resin T _LOH , one having an aromatic ring is preferably used. Examples of the tackifying resin T _LOH having an aromatic ring include the above-mentioned aromatic petroleum resins, aliphatic/aromatic copolymer petroleum resins, styrene resins, coumarone-indene resins, styrene-modified terpene resins, and phenol-modified terpene resins. resin, rosin phenol resin, and the like. Among them, it is more preferable to use the tackifier resin T _LOH1 having a softening point of 120° C. or higher as the tackifier resin T _LOH having an aromatic ring. The tackifying resin T _LOH1 having an aromatic ring is particularly preferably used for an adhesive layer containing a base polymer containing a monovinyl-substituted aromatic compound such as styrene as a main monomer. The tackifying resin T _LOH1 generally has a high softening point at which compatibility with the base polymer tends to decrease, but the hydroxyl value is limited to 30 mgKOH/g or less. It is easily compatible with the hard domain composed of the compound unit, and the heat resistance of the pseudo-crosslinking by the hard domain can be improved.

Preferred examples of materials that have a hydroxyl value of 30 mgKOH/g or less, a softening point of 120° C. or more, and can be used as the aromatic ring-containing tackifying resin T _LOH1 include aromatic petroleum resins, aliphatic/aromatic Copolymerized petroleum resins, styrenic resins and coumarone-indene resins can be mentioned. The aliphatic/aromatic copolymer petroleum resin has a copolymerization ratio of the C5 fraction of less than 15% by weight (more preferably less than 10% by weight, still more preferably less than 5% by weight, for example less than 3% by weight). is preferred. In addition, the copolymerization ratio of the C9 fraction is preferably 55% by weight or more (more preferably 60% by weight or more, still more preferably 65% by weight or more). Among the preferred tackifying resins T _LOH1 are aromatic petroleum resins and styrenic resins (eg, α-methylstyrene/styrene copolymer resins).

The amount of tackifying resin T _LOH1 used is not particularly limited. From the viewpoint of deterioration suppression, high-temperature cohesiveness, etc., the amount of the tackifying resin _TLOH1 used with respect to 100 parts by weight of the base polymer is suitably about 5 parts by weight or more, preferably about 10 parts by weight or more, more preferably about 10 parts by weight or more. is about 15 parts by weight or more, more preferably about 20 parts by weight or more, and particularly preferably about 25 parts by weight or more. In addition, from the viewpoint of achieving both high-level adhesion reliability and temporary adhesion in the main adhesion, the amount of the tackifier resin T _LOH1 used relative to 100 parts by weight of the base polymer can be, for example, about 100 parts by weight or less. Normally, about 80 parts by weight or less (for example, about 60 parts by weight or less) is preferable. Considering low-temperature adhesion performance (for example, temporary adhesion), the amount of the tackifier resin T _LOH1 to be used is preferably about 40 parts by weight or less, and may be about 35 parts by weight or less, relative to 100 parts by weight of the base polymer.

An adhesive layer according to a preferred embodiment contains a tackifier resin T _LOH2 having a softening point of less than 120° C. as the tackifier resin _LOH . By using the tackifying resin T _LOH2 , an adhesive sheet with better temporary adhesiveness can be realized. The lower softening point of the tackifier resin T _LOH2 is not particularly limited. Generally, those having a softening point of about 40° C. or higher (typically about 60° C. or higher) are preferably used. From the viewpoint of achieving a high level of both adhesion reliability and temporary adhesion in the final adhesion, a tackifier resin T _LOH2 having a softening point of about 80° C. or higher (more preferably about 100° C. or higher) and less than 120° C. is preferably used. can be done. Among them, it is preferable to use a tackifying resin T _LOH2 having a softening point of 110°C or more and less than 120°C.

The tackifying resin T _LOH2 is not particularly limited except that it has a hydroxyl value of 30 mgKOH/g or less and a softening point of less than 120°C. The presence or absence of a terpene skeleton, the presence or absence of a rosin skeleton, etc.) are not particularly limited. It is possible to appropriately select and use from among the various tackifying resins described above (petroleum resins, styrene resins, coumarone-indene resins, terpene resins, modified terpene resins, rosin resins, rosin derivative resins, ketone resins, etc.). can.

The technology disclosed herein can be preferably implemented in a mode in which the adhesive layer contains at least one of a petroleum resin and a terpene resin as the tackifying resin T _LOH2 . For example, the main component of the tackifying resin T _LOH2 (that is, the component occupying more than 50% by weight of the tackifying resin T _LOH2 ) is a petroleum resin composition, a terpene resin composition, a petroleum resin and a terpene resin A composition or the like that is a combination can be preferably employed. From the viewpoint of adhesive strength and compatibility, it is preferred that the main component of the tackifying resin T _LOH2 is a terpene resin (eg, α-pinene polymer or β-pinene polymer). Substantially all (eg, 95% or more by weight) of the tackifier resin T _LOH2 may be a terpene resin.

The amount of tackifying resin T _LOH2 used is not particularly limited. From the viewpoint of suppressing deterioration, temporary adhesion, etc., the amount of the tackifying resin T _LOH2 used relative to 100 parts by weight of the base polymer is appropriately about 10 parts by weight or more, preferably about 20 parts by weight or more. It is preferably about 30 parts by weight or more, more preferably about 40 parts by weight or more (for example, 45 parts by weight or more). In addition, from the viewpoint of achieving both high-level adhesion reliability and temporary adhesion in the main adhesion, the amount of the tackifier resin T _LOH2 used relative to 100 parts by weight of the base polymer can be, for example, about 120 parts by weight or less. Generally, about 90 parts by weight or less is preferable, and about 70 parts by weight or less (for example, about 60 parts by weight or less) is more preferable.

In a preferred embodiment, the tackifying resin T _LOH having a hydroxyl value of 30 mgKOH/g or less includes a tackifying resin T _LOH1 having a softening point of 120° C. or higher, and a tackifying resin T _LOH2 having a softening point of less than 120° C. used together. The content ratio is not particularly limited, and from the viewpoint of achieving both adhesion reliability and temporary adhesion in the final adhesion at a high level, the ratio of the content of the tackifier resin T _LOH2 to the content of the tackifier resin T _LOH1 (T _LOH2 /T _LOH1 ) is suitably about 0.5 or more, preferably about 0.8 or more, more preferably about 1.2 or more, and even more preferably about 1.5 or more. Also, the ratio (T _LOH2 /T _LOH1 ) is suitably about 3 or less, preferably about 2.5 or less, more preferably about 2 or less, and even more preferably about 1.8 or less.

The amount of the tackifier resin T _LOH used (the total amount when the tackifier resin T _LOH1 and the tackifier resin T _LOH2 are used together) is not particularly limited. From the viewpoint of preferably exhibiting the effect of the technique disclosed herein, the amount of the tackifying resin T _LOH used with respect to 100 parts by weight of the base polymer is appropriately about 15 parts by weight or more, preferably about 35 parts by weight. Above, more preferably about 50 parts by weight or more, still more preferably about 65 parts by weight or more (for example, about 70 parts by weight or more). The amount of the tackifying resin T _LOH used relative to 100 parts by weight of the base polymer can be, for example, about 220 parts by weight or less, usually about 170 parts by weight or less, and about 120 parts by weight or less (e.g., about 100 parts by weight). part or less) is more preferable.

<Tackifying resin _THOH >
In one aspect of the technology disclosed herein, instead of the tackifying resin T _LOH having a hydroxyl value of 30 mgKOH/g or less, or in combination with the tackifying resin T _LOH , a tackifying resin having a hydroxyl value exceeding 30 mgKOH/g T _HOH can be used. The hydroxyl value of the tackifying resin _THOH may be, for example, about 40 mgKOH/g or more, or about 50 mgKOH/g or more. The technology disclosed herein can also be implemented in a mode containing a tackifying resin (T _HO1 ) having a hydroxyl value of about 80 mgKOH/g or more (for example, 90 mgKOH/g or more) as the tackifying resin T _HOH . The hydroxyl value of the tackifier resin T _LOH is typically about 200 mg KOH/g or less, preferably about 150 mg KOH/g or less (eg 120 mg KOH/g or less).

The tackifying resin T _HOH is not particularly limited, and any of the various tackifying resins described above and having a hydroxyl value of more than 30 mgKOH/g can be used. For example, terpene phenol resin, rosin phenol resin, polymerized rosin, esterified product of polymerized rosin, and the like can be used. Typical examples include phenolic resins (including terpene phenolic resins and rosin phenolic resins) having a phenolic structure in the molecule. Such tackifying resin T _HOH can be used singly or in combination of two or more.

The amount of the tackifying resin _THOH to be used is not particularly limited, and can be appropriately set according to the purpose and application of the adhesive composition. From the viewpoint of suppressing deterioration, etc., the amount of the tackifying resin _THOH used relative to 100 parts by weight of the base polymer can be, for example, approximately 100 parts by weight or less, and is suitably approximately 60 parts by weight or less, preferably It is about 30 parts by weight or less, more preferably 10 parts by weight or less. For example, by limiting the amount of phenolic resin used as the tackifying resin _THOH , deterioration of the adhesive tends to be favorably suppressed. The technology disclosed herein can also be practiced in a mode in which the amount of the tackifying resin T _HOH used is about 5 parts by weight or less (for example, about 1 part by weight or less) relative to 100 parts by weight of the base polymer, and the adhesive layer is It can be preferably carried out even in a mode in which the tackifying resin _THOH is not substantially contained. In addition, the fact that the adhesive layer does not substantially contain the tackifying resin _THOH means that the amount of the tackifying resin _THOH is less than 0.1 parts by weight with respect to 100 parts by weight of the base polymer.

<Crosslinking agent>
The technology disclosed herein can be preferably practiced in a mode provided with an adhesive layer comprising an adhesive in which the base polymer is non-crosslinked (non-crosslinked adhesive). Here, the term "adhesive layer made of a non-crosslinkable adhesive" refers to an intentional treatment for forming chemical bonds between base polymers when forming the adhesive layer (i.e., crosslinking treatment, such as It refers to an adhesive layer that has not been mixed with a cross-linking agent, etc.). Such adhesive layers and adhesive compositions used to form the adhesive layers may be substantially free of cross-linking agents such as isocyanate compounds. The adhesive composition substantially does not contain a cross-linking agent means that the content of the cross-linking agent contained in the adhesive composition is less than 0.1% by weight (for example, 0 to 0.05% by weight). .

<Other ingredients>
The adhesive composition disclosed herein may optionally contain a leveling agent, a cross-linking aid, a plasticizer, a softening agent, a filler (typically inorganic particles), a coloring agent (pigment, dye, etc.), an electrifying agent, It may contain various additives commonly used in the field of adhesives, such as inhibitors, anti-aging agents, ultraviolet absorbers, antioxidants, and light stabilizers. As for such various additives, conventionally known ones can be used in a conventional manner. From the viewpoint of preventing deterioration, aging, etc., the adhesive composition disclosed herein is used in an amount of about 0.1 to 10 parts by weight (preferably about 1 to 7 parts by weight, for example, about 1.0 part by weight) per 100 parts by weight of the base polymer. 5 to 5 parts by weight) of an antioxidant is preferably contained. In addition, the adhesive disclosed herein does not substantially contain liquid rubber such as polybutene (for example, the content per 100 parts by weight of the base polymer is 1 part by weight or less, and may be 0 part by weight. .) can be preferably implemented in the following manner. With such an adhesive, an adhesive sheet having excellent adhesion reliability during final adhesion can be realized.

In a preferred embodiment, the adhesive composition is such that the total amount of the base polymer and the tackifying resin is 90% by weight of the total weight of the adhesive (that is, the weight of the adhesive layer composed of this adhesive). It can be a composition that occupies the above. For example, an aspect in which the total amount of the base polymer and the tackifying resin is 90 to 99.8% by weight (typically, for example, 95 to 99.5% by weight) of the total weight of the adhesive can be preferably adopted. .
In another preferred embodiment, the adhesive composition may be substantially free of chelate compounds. Here, the chelate compound is, for example, a chelate compound of an alkaline earth metal oxide and a resin (alkylphenol resin, etc.) having a functional group (hydroxyl group, methylol group, etc.) with which the oxide can be coordinated. Point. The technique disclosed herein can be preferably practiced in a mode in which the adhesive composition does not contain such a chelate compound at all, or the content of the chelate compound is 1% by weight or less. According to this aspect, an adhesive sheet having more excellent adhesive strength can be realized.

The form of the adhesive composition disclosed herein is not particularly limited. is dispersed in an aqueous solvent (aqueous dispersion type, typically aqueous emulsion type), a hot-melt adhesive composition, and the like. A solvent-based adhesive composition is particularly preferred from the viewpoint of achieving higher adhesive performance. Such a solvent-based adhesive composition is typically prepared in the form of a solution containing each component described above in an organic solvent. The organic solvent can be appropriately selected from known or commonly used organic solvents. For example, aromatic compounds (typically aromatic hydrocarbons) such as toluene and xylene; acetic esters such as ethyl acetate and butyl acetate; aliphatic or alicyclic hydrocarbons such as hexane, cyclohexane and methylcyclohexane halogenated alkanes such as 1,2-dichloroethane; ketones such as methyl ethyl ketone and acetylacetone; Although not particularly limited, it is usually appropriate to adjust the solid content (NV) of the solvent-type adhesive composition to 30 to 65% by weight (eg, 40 to 55% by weight). If the NV is too low, the manufacturing cost tends to increase, and if the NV is too high, the handleability such as coatability may deteriorate.

As a method for obtaining an adhesive sheet from an adhesive composition, various conventionally known methods can be applied. For example, a method (direct method) of forming an adhesive layer by directly applying (typically applying) an adhesive composition to a substrate and drying it can be preferably employed. Alternatively, the adhesive composition is applied to a surface having good releasability (e.g., the surface of a release liner, the back surface of a support substrate that has been subjected to release treatment, etc.) and dried to form an adhesive layer on the surface. The method is preferably employed for making substrateless adhesive sheets. After forming the adhesive layer, a method of transferring the adhesive layer to the substrate (transfer method) may be adopted.
Application of the adhesive composition can be carried out using known or commonly used coaters such as gravure roll coaters, reverse roll coaters, kiss roll coaters, dip roll coaters, bar coaters, knife coaters and spray coaters. From the viewpoint of improving production efficiency, etc., it is preferable to dry the adhesive composition under heating. Usually, a drying temperature of about 40° C. to 150° C. (typically 40° C. to 120° C., eg 50° C. to 120° C., further 70° C. to 100° C.) can be preferably employed. Although the drying time is not particularly limited, it may be about several tens of seconds to several minutes (for example, within about 5 minutes, preferably about 30 seconds to 2 minutes). An additional drying step may then be provided if desired. The adhesive layer is typically formed continuously, but may be formed in a regular or random pattern such as dots or stripes depending on the purpose and application.

Although not particularly limited, the thickness of the adhesive layer is suitably about 3 mm or less, preferably about 1 mm or less, from the viewpoint of thinning, miniaturization, weight saving, resource saving, etc. It is more preferably about 0.7 mm or less, still more preferably about 0.5 mm or less (for example, about 0.4 mm or less). Since the thickness of the adhesive layer is limited, the amount of impregnation into an adherend such as a fabric is also limited, so the influence of the impregnation on the deformation recovery (e.g. stretchability) of the adherend is also reduced. . In addition, from the viewpoint of ensuring good adhesive properties, the thickness is suitably about 0.01 mm or more, preferably about 0.03 mm or more, more preferably about 0.05 mm or more, and further preferably about 0.05 mm or more. Preferably, it is about 0.1 mm or more. In the case of a double-sided adhesive sheet with a substrate, it is preferable to have a configuration in which an adhesive layer having the thickness described above is provided on each side of the substrate.

<Base material>
When the technology disclosed herein is applied to a double-sided adhesive sheet with a substrate or a single-sided adhesive sheet with a substrate, examples of the substrate include polypropylene film, ethylene-propylene copolymer film, polyester film, polyurethane film, poly Plastic films such as vinyl chloride films; foam sheets made of polyurethane foam, polyethylene foam, polychloroprene foam, etc.; various fibrous materials (natural fibers such as linen and cotton; , semi-synthetic fibers such as acetate, etc.) woven fabrics and non-woven fabrics (including papers such as Japanese paper and high-quality paper) made by single or blended spinning, etc.; Metals such as aluminum foil and copper foil foil; and the like can be appropriately selected and used according to the application of the adhesive sheet. As the plastic film (typically refers to a non-porous plastic film, which is a concept to be distinguished from woven fabric and non-woven fabric), either a non-stretched film or a stretched (uniaxially stretched or biaxially stretched) film is also available. In addition, the surface of the substrate on which the adhesive layer is to be provided may be subjected to surface treatment such as application of a primer or corona discharge treatment. The thickness of the base material can be appropriately selected depending on the purpose, but is generally about 2 μm to 500 μm (typically 10 μm to 200 μm).

<Release liner>
As the release liner, a conventional release paper or the like can be used, and there is no particular limitation. For example, a release liner having a release treatment layer on the surface of a base material such as plastic film or paper, or a release liner made of a low-adhesive material such as a fluoropolymer (polytetrafluoroethylene, etc.) or a polyolefin resin (polyethylene, polypropylene, etc.) etc. can be used. The release treatment layer may be formed by surface-treating the substrate with a release treatment agent such as a silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide-based release agent.

<Application>
The adhesive sheet disclosed herein is useful for joining members (for example, fixing various parts in such products) in various types of OA equipment, home electric appliances, automobiles, clothes, household goods, housing goods, leisure goods, and the like. be. The adhesive sheet disclosed herein can be used for bonding hard members such as resin parts. , leather, paper, rubber sheets, resin sheets, and other flexible materials. Among them, cloth is a preferred application target of the technology disclosed herein. The fabric includes woven fabrics and knitted fabrics formed from natural fibers, synthetic fibers, semi-synthetic fibers, and composite fibers thereof, and encompasses all so-called fabrics. Leather includes artificial leather, synthetic leather, and semi-synthetic leather.

Suitable examples of products containing the flexible material include clothes such as coats, jackets, shirts, pants, and underwear; household items such as shoes, bags, and towels; household items such as curtains, carpets, sofas, and bedding; Sporting goods such as suits and the like can be mentioned. The adhesive sheet disclosed herein is preferably used as an alternative joining (seamless joining) means for sewing in the above applications. Bonding (typically seamless bonding) of elastic fabrics such as underwear is a particularly preferred application of the technology disclosed herein. Such a stretchable material can be formed from natural fibers such as cotton, various synthetic fibers such as acrylic, polyester, urethane, natural/synthetic composite fibers, and the like. The manner in which the fabric or the like is joined by the adhesive sheet is not particularly limited. may be appropriately employed, such as a mode in which the are partially overlapped and joined via an adhesive sheet. The technology disclosed herein can be preferably implemented in a mode in which adherends are partially overlapped and joined via an adhesive sheet.

<Fabric bonded by thermoplastic adhesive>
As described above, the adhesive sheet disclosed herein can be preferably used for joining fabrics (typically seamless joining). Thus, according to the technology disclosed herein, fabrics bonded by a thermoplastic adhesive (adhesive-bonded fabrics) are provided. Such adhesive-bonded fabrics are produced, for example, by placing a thermoplastic adhesive sheet between one fabric and another fabric for temporary bonding, followed by heat pressing. By adopting this method, it is possible to accurately and simply join fabrics (typically seamless joining) without the need for sewing. Products can be manufactured with high productivity. A product such as clothing manufactured in such a manner can provide excellent wearing comfort because the adhesive joints follow the flexibility and stretchability of the clothing.

Matters disclosed by this specification include the following.
(1) A thermoplastic adhesive sheet having a thermoplastic adhesive layer,
The following characteristics:
(A) A thermoplastic adhesive sheet is attached to a polyester urethane foam having a thickness of 10 mm in an environment of 23° C. and 50% RH by reciprocating a 2 kg roller once, left in the same environment for 30 minutes, and then stretched. The peel strength measured under conditions of 300 mm/min and a peel angle of 180 degrees is 2 N/10 mm or more; and (B) A thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm is prepared, and the measurement sample is After being stretched 50% at a speed of 300 mm / min at 23 ° C. and held for 3 seconds, when contracted at a speed of 300 mm / min, the contraction strength F S30 _{% against the elongation strength F E30%} at _30% elongation length. The hysteresis obtained from the ratio [F _S30% /F _E30% ] is 35% or more;
A thermoplastic adhesive sheet that satisfies
(2) the following properties:
(C) A 30% modulus measured at a speed of 300 mm/min at 23°C for a thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm is 0.6 MPa or less;
The thermoplastic adhesive sheet according to (1) above, further satisfying
(3) the following characteristics:
(D) The thermoplastic adhesive sheet was pressed against a stainless steel plate under the conditions of 120°C, 0.2 MPa, and 10 seconds, left at 23°C for 30 minutes, and then measured under the conditions of a tensile speed of 300 mm/min and a peeling angle of 180 degrees. The peel strength is 15 N / 10 mm or more;
The thermoplastic adhesive sheet according to (1) or (2) above, further satisfying
(4) The thermoplastic adhesive sheet according to any one of (1) to (3) above, wherein the thermoplastic adhesive layer is a rubber-based adhesive layer containing a rubber-based polymer as a base polymer.
(5) The thermoplastic adhesive sheet according to (4) above, wherein the thermoplastic adhesive layer contains, as a base polymer, a block copolymer of a monovinyl-substituted aromatic compound and a conjugated diene compound.
(6) The thermoplastic adhesive sheet according to (5) above, wherein the base polymer is a styrenic block copolymer.
(7) The thermoplastic adhesive sheet according to (5) or (6) above, wherein the base polymer has a diblock ratio of 65% or more.
(8) The thermoplastic adhesive according to any one of (1) to (7) above, wherein the thermoplastic adhesive layer contains, as a tackifying resin, a tackifying resin T _LOH having a hydroxyl value of 30 mgKOH/g or less. sheet.
(9) The thermoplastic adhesive sheet according to (8) above, wherein the tackifying resin T _LOH contains a tackifying resin T _LOH1 having a softening point of 120° C. or higher.
(10) The thermoplastic adhesive sheet according to (9) above, wherein the tackifying resin T _LOH1 contains a tackifying resin having an aromatic ring.
(11) The thermoplastic adhesive sheet according to any one of (8) to (10) above, wherein the tackifying resin _LOH contains a tackifying resin T _LOH2 having a softening point of less than 120°C.
(12) The content of the tackifying resin T _LOH in the thermoplastic adhesive layer is 15 to 220 parts by weight with respect to 100 parts by weight of the base polymer contained in the thermoplastic adhesive layer, above (8) The thermoplastic adhesive sheet according to any one of (11).
(13) The thermoplastic adhesive sheet according to any one of (1) to (12) above, wherein the thermoplastic adhesive layer does not contain a tackifying resin T _HOH having a hydroxyl value exceeding 30 mgKOH/g.
(14) The thermoplastic adhesive sheet according to any one of (1) to (13) above, wherein the thermoplastic adhesive layer is a non-crosslinkable adhesive layer.
(15) The thermoplastic adhesive sheet according to any one of (1) to (14) above, wherein the thermoplastic adhesive sheet has a thickness of 0.03 mm to 1 mm.
(16) The thermoplastic adhesive sheet according to any one of (1) to (15) above, which is configured as a substrate-less adhesive sheet consisting only of the thermoplastic adhesive layer.
(17) The thermoplastic adhesive sheet according to any one of (1) to (16) above, which is used for bonding fabrics.
(18) A thermoplastic adhesive sheet with a release liner comprising the thermoplastic adhesive sheet according to any one of (1) to (17) above and a release liner for protecting the adhesive surface of the thermoplastic adhesive sheet.
(19) A fabric bonded with the thermoplastic adhesive sheet according to any one of (1) to (18) above.

Several examples relating to the present invention are described below, but the present invention is not intended to be limited to those shown in such examples. In the following description, "parts" and "%" are by weight unless otherwise specified.

<Example 1>
[Preparation of thermoplastic adhesive composition]
100 parts of a styrene isoprene block copolymer (manufactured by Nippon Zeon Co., Ltd., product name "Quintac 3520", styrene content 15%, diblock ratio 78%) as a base polymer, and 50 parts of a terpene resin (Yasuhara Chemical) company, product name "YS resin PX1150N", softening point 115 ° C., hydroxyl value less than 1 mgKOH / g) and aromatic petroleum resin (manufactured by JX Nippon Oil & Energy, product name "Nisseki Neopolymer 150", softening Point 155 ° C., hydroxyl value less than 1 mgKOH / g) 30 parts, anti-aging agent (product name "IRGANOX 1010" manufactured by BASF) 3 parts, and toluene as a solvent Stir and mix, NV50% thermoplastic adhesion A formulation composition was prepared.

[Preparation of Thermoplastic Adhesive Sheet]
The thermoplastic adhesive composition prepared above is applied to the release-treated surface of release liner A that has been release-treated with a silicone-based release agent, and dried at 120° C. for 3 minutes to form a thermoplastic adhesive composition having a thickness of 0.2 mm. An adhesive layer was formed. A release liner B, which had been subjected to a release treatment with a silicone-based release agent, was attached to the thermoplastic adhesive layer. Thus, a substrate-less thermoplastic adhesive sheet comprising a thermoplastic adhesive layer was produced.

<Examples 2-3>
A thermoplastic adhesive sheet according to each example was produced in the same manner as in Example 1, except that the thickness of the thermoplastic adhesive layer was changed as shown in Table 1.

<Example 4>
A product name "No. 501K" manufactured by Nitto Denko Corporation was used as an adhesive sheet according to this example. "No. 501K" is a 0.17 mm-thick double-sided pressure-sensitive adhesive tape with a substrate in which acrylic pressure-sensitive adhesive layers are formed on both sides of a non-woven fabric substrate.

<Example 5>
100 parts of styrene-butadiene block copolymer (manufactured by Asahi Kasei Chemicals, product name "Suplen T-432", styrene content 30%) as a base polymer, and 120 parts of alicyclic hydrocarbon resin (manufactured by Arakawa Chemical Industries, product A thermoplastic adhesive composition with an NV of 50% was prepared by stirring and mixing the name "Alcon M-115", softening point 115° C.) and toluene as a solvent.
The thermoplastic adhesive composition prepared above is applied to the release-treated surface of release liner A that has been release-treated with a silicone-based release agent, and dried at 120° C. for 3 minutes to form a thermoplastic adhesive composition having a thickness of 0.05 mm. An adhesive layer was formed. A release liner B, which had been subjected to a release treatment with a silicone-based release agent, was attached to the thermoplastic adhesive layer. Thus, a substrate-less thermoplastic adhesive sheet comprising a thermoplastic adhesive layer was produced.

[Temporary adhesive strength to fabric]
The adhesive sheet according to each example was cut into strips with a width of 10 mm. Two commercially available undergarment fabrics cut into strips with a width of 20 mm were prepared, and under an environment of 23 ° C. and 50% RH, each of the two fabrics was applied to each adhesive surface of the adhesive sheet piece once with a roller of 2 kg. A measurement sample was produced by pressing and crimping. After the obtained measurement sample was left in the same environment for 30 minutes, the measurement sample was peeled off in a T-shape using a universal tension/compression tester. Specifically, one end in the longitudinal direction of the two fabrics joined by the adhesive sheet pieces in the measurement sample is grasped by the two chucks of the tester, one chuck is upward, the other chuck is downward, The two fabrics joined by the adhesive sheet pieces were separated in a T-shape by pulling each at a speed of 100 mm/min. When the plane of the measurement sample (the plane of the fabrics joined with the adhesive sheet) is 0 degrees, this T-type peeling is such that one fabric forms a T-shape at +90 degrees and the other at -90 degrees. It is peeling that peels off. The force required for this T-type peeling was measured with the above-mentioned tester, and this was defined as the temporary adhesion force to the fabric (temporary adhesion force to the fabric) [N/10 mm].
As the universal tension/compression tester, the device name "Tensile/compression tester, TG-1kN" manufactured by Minebea Co., Ltd. was used, but equivalents or commercially available devices can be used.

[Adhesive strength to fabric]
The conditions for crimping the adhesive sheet to the fabric according to each example were 150 ° C., 0.5 MPa, 15 seconds, and after crimping, it was left at room temperature (23 ° C.) for 1 hour, and then T-shaped peeling was performed. The adhesive strength to fabric (adhesive strength to fabric) [N/10 mm] was measured in the same manner as the evaluation of properties.

[30% elongation strength and 50% elongation residual strain]
The adhesive sheet according to each example was cut into strips with a width of 10 mm so as to have a measured length of 100 mm. In addition, two commercially available underwear fabrics cut into strips with a width of 20 mm so as to have a measurement length of 100 mm were prepared, and each of the two fabrics was placed on the adhesive sheet piece under an environment of 23 ° C. and 50% RH. A measurement sample was prepared by crimping each adhesive surface under crimping conditions of 150° C., 0.5 MPa, and 15 seconds. After leaving the obtained measurement sample at room temperature (23 ° C.) for 1 hour, it was set in a tensile compression tester so that the distance between chucks (measurement length) was 100 mm (L0), and the test was performed at 23 ° C. at 100 mm / min. It was stretched 50% at a speed (thus, stretched to 150 mm), held in the 50% stretched state for 3 seconds, then released and left for 30 minutes, and the measured length L1 [mm] was recorded. From the above operation, the strength when the measurement sample was elongated by 30% (30% elongation strength) [N] and the residual strain after standing for 30 minutes (50% elongation residual strain) [%] were determined. The above residual strain [%] is calculated by the formula:
Residual strain [%] = (L1-L0) / L0 × 100
requested from

Schematic structure of the adhesive sheet according to each example, 30% modulus [MPa], 30% hysteresis at 50% elongation [%], adhesive strength to foam [N / 10 mm], adhesive strength to SUS thermocompression [N / 10 mm], Table 1 shows the evaluation results of temporary adhesive strength to fabric [N / 10 mm], permanent adhesive strength to fabric [N / 10 mm], 30% elongation strength [N] and 50% elongation residual strain [%] of adhesive-bonded fabric. show.

As shown in Table 1, Examples 1 to 3 in which the foam adhesive strength (characteristic (A)) was 2 N/10 mm or more and the 30% hysteresis at 50% elongation (characteristic (B)) was 35% or more The thermoplastic adhesive sheet according to 3 exhibits a temporary adhesive strength of 0.1 N / 10 mm or more (specifically 0.4 to 0.6 N / 10 mm) to the fabric, and the fabric bonded with the adhesive sheet remains The strain was 5% or less. In contrast, the double-sided pressure-sensitive adhesive sheet with a nonwoven fabric substrate according to Example 4, whose hysteresis could not be measured due to breakage, had a residual strain of more than 5%. In addition, the adhesive sheet according to Example 5, which had an adhesive strength to foam of less than 2 N/10 mm, had a significantly low temporary adhesive strength to fabric, and did not have sufficient temporary adhesive strength. From the above evaluation results, although the absolute values of the adhesive strength to foam and the temporary adhesive strength to fabric differed, a certain correlation was shown because the surfaces of both adherends were rough surfaces. Further, among Examples 1 to 3 in which the 30% modulus was 0.6 MPa or less, the fabrics bonded with the adhesive sheet according to Example 1 having a thickness of 0.06 mm were the adhesive bonded fabrics according to Example 5 (adhesive The 30% elongation strength was kept low compared to the sheet with a 30% modulus of more than 0.6 MPa and a thickness of 0.05 mm, and the original flexibility of the fabric was retained. Furthermore, in Examples 1 to 3, in which the thermocompression bonding strength to SUS is relatively high, there is a tendency that the actual bonding strength to the fabric also increases. A relatively high correlation was observed.

From the above results, a thermoplastic adhesive sheet having an adhesive strength to foam of 2 N/10 mm or more and a 30% hysteresis at 50% elongation of 35% or more, that is, a thermoplastic that satisfies the characteristics (A) and (B) According to the adhesive sheet, it can be seen that it has temporary adhesiveness and deformation recovery, and can exhibit a good adhesive function. It is also found that a thermoplastic adhesive sheet having a 30% modulus of 0.6 MPa or less, that is, satisfying the characteristic (C) does not impair the flexibility of the adherend material. Furthermore, it can be seen that a thermoplastic adhesive sheet having a thermocompression bonding strength to SUS of 15 N/10 mm or more, that is, satisfying the characteristic (D) has excellent bonding reliability due to its strong bonding strength.

Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

1, 2, 3 Thermoplastic adhesive sheet 11 Adhesive layer (first adhesive layer)
12 second adhesive layer 15 substrates 21, 22 release liner

Claims (7)

A substrate-less thermoplastic adhesive sheet consisting only of a thermoplastic adhesive layer,
The thermoplastic adhesive layer contains a styrene isoprene block copolymer as a base polymer and a tackifying resin T _LOH having a hydroxyl value of 30 mgKOH/g or less as a tackifying resin,
The styrene content of the styrene isoprene block copolymer is 25% by weight or less,
The tackifying resin T _LOH comprises at least one selected from the group consisting of petroleum resins and terpene resins,
The tackifying resin T _LOH contains a tackifying resin T _LOH1 having a softening point of 130° C. or more and a tackifying resin T _LOH2 having a softening point of less than 120° C.,
the tackifying resin T _LOH2 comprises a terpene resin;
The amount of the tackifier resin T _LOH used relative to 100 parts by weight of the base polymer is 15 parts by weight or more and 220 parts by weight or less,
The following properties:
(A) A thermoplastic adhesive sheet is attached to a polyester urethane foam having a thickness of 10 mm in an environment of 23° C. and 50% RH by reciprocating a 2 kg roller once, left in the same environment for 30 minutes, and then stretched. The peel strength measured under conditions of 300 mm/min and a peel angle of 180 degrees is 2 N/10 mm or more; and (B) A thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm is prepared, and the measurement sample is After being stretched 50% at a speed of 300 mm / min at 23 ° C. and held for 3 seconds, when contracted at a speed of 300 mm / min, the contraction strength F S30 _{% against the elongation strength F E30%} at _30% elongation length. The hysteresis obtained from the ratio [F _S30% /F _E30% ] is 35% or more;
A thermoplastic adhesive sheet that satisfies The following properties:
(C) A 30% modulus measured at a speed of 300 mm/min at 23°C for a thermoplastic adhesive sheet measurement sample having a measurement length of 100 mm is 0.6 MPa or less;
The thermoplastic adhesive sheet according to claim 1, further satisfying The following properties:
(D) The thermoplastic adhesive sheet was pressed against a stainless steel plate under the conditions of 120°C, 0.2 MPa, and 10 seconds, left at 23°C for 30 minutes, and then measured under the conditions of a tensile speed of 300 mm/min and a peeling angle of 180 degrees. The peel strength is 15 N / 10 mm or more;
The thermoplastic adhesive sheet according to claim 1 or 2, further satisfying The thermoplastic adhesive sheet according to any one of claims 1 to 3, wherein the thermoplastic adhesive layer is a non-crosslinkable adhesive layer. The thermoplastic adhesive sheet according to any one of claims 1 to 4, wherein the thermoplastic adhesive sheet has a thickness of 0.03 mm to 1 mm. The thermoplastic adhesive sheet according to any one of claims 1 to 5, which is used for bonding fabrics. Fabrics bonded by a thermoplastic adhesive sheet according to any one of claims 1-6.

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