TW201840773A - Thermal adhesion tape and method for producing thermal adhesion tape promoting hardening of an adhesive layer when heated, and preventing the adhesive layer from be cured when not heated - Google Patents

Abstract

Provided is a thermal adhesion tape which promotes hardening of an adhesive layer when heated, and which is less likely to be hardened when it is not heated during storage or the like. The thermal adhesion tape (1) of the present invention is a thermal adhesive tape (1) thermally bonded to an adhered body by thermocompression bonding, and includes a base material (2) formed of a non-woven fabric, and an adhesive layer (3) which is provided on each of one and the other surface sides of the base material (2), and contains an acrylonitrile-butadiene rubber, a phenol resin, a peroxide which is decomposed to generate an acid, and a phenol resin crosslinking agent, wherein the peroxide has a half-life temperature of 130 DEG C or higher and 170 DEG C or lower, and when the acrylonitrile-butadiene rubber is used in an amount of 100 parts by mass, the adhesive layer (3) contains 0.5 parts by mass or more and 5 parts by mass or less of the peroxide.

Description

Thermal adhesive tape and manufacturing method of thermal adhesive tape

The present invention relates to a heat-adhesive tape. Specifically, it relates to a heat-adhesive tape attached to a glass fiber cloth or the like.

It has been known from the past that a heat-adhesive tape is used to harden an adhesive layer by thermal compression bonding to an adherend. The heat-adhesive tape is composed of, for example, a base material and an adhesive layer provided on both sides of the base material, and the two adhesive layers are respectively bonded to an adherend such as a glass fiber cloth by thermal compression bonding, and is used for connection and adhesion. Body use.

Patent Document 1 discloses an adhesive tape for a semiconductor device, which contains an acrylonitrile-butadiene copolymer (NBR), a novolac-type phenol resin, and an epoxy resin in an adhesive layer. It can self-crosslink and contain dialkyl peroxides. Patent Document 2 discloses a curable resin composition comprising vinyl benzyl etherified novolac resin, novolac type or cresol novolac type phenol resin, organic peroxides such as diisophenylpropyl peroxide, and hexamethylene Made of methyltetramine. Patent Document 3 discloses a sealant for a liquid crystal display element, which contains a partially esterified epoxy (meth) acrylate resin, an organic peroxide such as octyl peroxide, a phenol resin, and an organic silicon compound.

Patent Document 1: Japanese Patent Application Laid-Open No. 5-291360 Patent Document 2: Japanese Patent Application Laid-Open No. 6-329875 Patent Document 3: Japanese Patent Application Laid-Open No. 9-194567

[Questions to be Solved by the Invention]

In order to achieve the adhesion of the heat-adhesive tape to the adherend in a short time, an acid is contained in the adhesive layer, and the phenol resin contained in the adhesive layer can be promoted by the acid during the thermal compression bonding of the heat-adhesive tape. The reaction of a cross-linking agent (hardener) promotes the hardening of the adhesive layer by using this. However, if an acid is contained in the adhesive layer, the reaction of the phenol resin and the crosslinking agent is gradually promoted by the acid even when the thermal adhesive tape is not heated, such as during storage of the thermal adhesive tape, which causes the adhesive layer to harden. get on. If the adhesive layer is hardened before the thermal adhesive tape is thermocompression-bonded, the adhesive force of the thermal adhesive tape to the adherend may not be sufficiently obtained even if the adherend is thermally compression-bonded to the thermal adhesive tape.目的 An object of the present invention is to provide a heat-adhesive tape, which can promote the curing of the adhesive layer when heated, and hardly harden the adhesive layer when not heated, such as during storage. [Means for solving problems]

The heat-adhesive tape of the present invention is a heat-adhesive tape that is bonded to an adherend by thermal compression bonding, and is characterized by having a base material composed of a non-woven fabric; and an adhesive layer provided on one side of the base material and Each surface side of the other side contains acrylonitrile-butadiene rubber, a phenol resin, a peroxide that generates an acid due to decomposition, and a phenol resin cross-linking agent.

The peroxide here preferably has a half-life temperature of 130 ° C to 170 ° C.

On the other hand, when the acrylonitrile-butadiene rubber is 100 parts by mass, the adhesive layer may contain 0.5 to 5 parts by mass of a peroxide.

The thickness of the entire heat-adhesive tape is preferably 100 μm or more and 250 μm or less.

In addition, the method for producing a thermal adhesive tape of the present invention is characterized by including the following steps: a release liner, a substrate preparation step, preparing a substrate composed of a release liner and a non-woven fabric; Solution for the adhesive layer of acrylonitrile-butadiene rubber, phenol resin, peroxides that generate acid due to decomposition, and phenol resin cross-linking agent; the first adhesive layer forming step, applying the adhesive layer solution to a release liner A laminating step to form a first adhesive layer; a laminating step in which one surface side of the substrate is adhered to the first adhesive layer formed by the release liner; and a second adhesive layer forming step of coating the adhesive layer with a solution On the other surface side of the substrate to form a second adhesive layer. [Effect of the invention]

According to the present invention, it is possible to provide a heat-adhesive tape, which can accelerate the curing of the adhesive layer when heated, and hardly harden the adhesive layer when not heated, such as during storage.

Embodiments for carrying out the present invention will be described in detail below. The present invention is not limited to the following aspects. Various changes can be made within the scope of the gist. Moreover, the drawings used are for the purpose of illustrating the present inventors, and are not intended to represent actual sizes.

<Explanation of the overall structure of a heat-adhesive tape> (1) It is sectional drawing which shows the heat-adhesive tape 1 used by this embodiment. The thermal adhesive tape 1 shown in the figure includes a base material 2 and an adhesive layer 3 provided on each surface side of one side and the other side of the base material 2. In addition, for convenience of explanation, the adhesive layer 3 on the upper part of one surface side in the figure is also referred to as an adhesive layer 3a (first adhesive layer), and the adhesive layer 3 on the lower part of the other surface side in the figure is referred to as an adhesive layer. 3b (second adhesion layer). Although not shown, in FIG. 1, the release layer and the like may be provided on the surface side of the adhesive layer 3 opposite to the substrate 2.

The heat-adhesive tape 1 is bonded to the adherend by thermocompression bonding. Specifically, for example, when the adherend is a glass fiber cloth, in the manufacturing step of manufacturing the glass fiber cloth, the ends of the original fabric in which the long-sized glass fiber cloth is wound into a roll shape are joined to each other, and the like. use. At this time, the ends of the roller-shaped raw fabric are sandwiched with each other by heat-adhesive tape 1, and then the portions are pressed under heat. As a result, the adhesive layer 3 is hardened, and the ends of the original fabric are joined to each other by heat-adhesive tape 1. That is, the heat-adhesive tape 1 of this embodiment is different from an adhesive tape which is joined to an adherend by an adhesive force unless thermal compression bonding is performed.

The heat-adhesive tape 1 of this embodiment preferably has a thickness of 100 μm or more and 250 μm or less as a whole. When the thickness of the thermal adhesive tape 1 is less than 100 μm, it is difficult to maintain the strength against the shearing force. Here, the term "shearing force" refers to a force in a direction in which the surface of the adhesive tape is thermally bonded. In addition, if the thickness of the heat-adhesive tape 1 exceeds 250 μm, when the heat-adhesive tape 1 is to be rolled into a roll-shaped product, the diameter of the roll will become too large and wrinkles will easily occur. In the manufacturing step of the hot-adhesive tape 1, a solvent is liable to remain, and unevenness is easily generated on the surface of the adhesive layer 3 to deteriorate the appearance.

<Base material> The base material 2 is a support which forms the adhesion layer 3. The base material 2 is required to have a function of ensuring the mechanical strength of the entire heat-adhesive tape 1, and at the same time, it can follow the function of attaching the adherend of the heat-adhesive tape 1 to be soft and capable of changing its shape.

In this embodiment, the base material 2 is made of a non-woven fabric. That is, the base material 2 is a sheet-like thing in which fibers of a non-woven fabric are woven without being woven. In this embodiment, the fibers constituting the nonwoven fabric are not particularly limited. For example, polyester fibers, rayon fibers, polyethylene fibers, polypropylene fibers, polyolefin fibers, polyamide fibers, glass fibers, nylon fibers, and the like can be used.

Since the base material 2 is a non-woven fabric, there are many openings H between the fibers. Therefore, the reason will be described in detail later. When the base layer 2 is selected to form the bonding layer 3, a non-woven fabric is preferred in which the components constituting the bonding layer 3 do not enter the opening H of the bonding layer 3. As a result, as shown in the figure, the adhesive layer 3a provided on the surface side of one side of the base material 2 and the adhesive layer 3b provided on the other surface side of the base material 2 are joined through the opening H of the nonwoven fabric. A joint portion 3 c is formed in the opening portion H. In this embodiment, the occurrence of the joint portion 3c improves the adhesion between the base material 2 and the adhesive layer 3, and prevents the layer of the base material 2 itself from being cracked, so that the cohesive force originally possessed by the adhesive layer 3 can be fully exerted. . Also in the figure, all of the openings H form the joints 3c, but this need not necessarily be the case, and it is sufficient if the joints 3c are formed in a part of the openings H.

2 is formed on the substrate adhesion layer 3, in order that the components constituting the adhesive layer 3 H intrusion opening portion thereof, the non-woven fabric of a basis weight of ² or less to 40g / m preferably. When the unit weight of the non-woven fabric exceeds 40 g / m ² , the size of the opening H becomes too small, making it difficult for the components constituting the adhesive layer 3 to enter the opening H. As a result, it is difficult to form the joint portion 3c, and a sufficient adhesive force of the adhesive layer 3 cannot be obtained. The unit weight of the nonwoven fabric is more preferably 5 g / m ² or more. When the unit weight of the non-woven fabric is less than 5 g / m ² , the transportability of the substrate 2 is deteriorated, and the operation of bonding the substrate 2 to the adhesive layer 3 a (first adhesive layer) becomes difficult. Further, the strength of the thermal adhesive tape 1 after the adhesive layer 3 is formed on the base material 2 may decrease. The thickness of the substrate 2 is preferably 30 μm or more and 120 μm or less.

<Adhesive Layer> Adhesive layer 3 is a functional layer that is hardened by heating, and at this time, pressure is applied to thermally bond the adhesive tape 1 to the adherend to produce a functional layer. Based on this embodiment, the adhesive layer 3 contains an acrylonitrile-butadiene rubber, a phenol resin, a peroxide, and a phenol resin crosslinking agent.

The structure of the acrylonitrile-butadiene rubber is not particularly limited. For example, any one of a linear acrylonitrile-butadiene rubber and a branched structure acrylonitrile-butadiene rubber can be used. However, in this embodiment, it is preferable to use an acrylonitrile-butadiene rubber having a branched structure.丙烯 Acrylonitrile-butadiene rubber having a branched structure can impart moderate softness to the adhesive layer 3, and at the same time can provide extremely high cohesive force. The acrylonitrile-butadiene rubber having a branched structure used in this embodiment is classified into acrylonitrile-butadiene rubber as a thermal rubber produced at a polymerization temperature of 25 to 50 ° C. Expression 1

The general formula (1) of the following formula 2 is a structural formula of a linear acrylonitrile-butadiene rubber. Here, m and n are integers of 1 or more. The acrylonitrile-butadiene rubber having a branch structure represented by Formula 1 is a double bond crack of butadiene in the general formula (1), and the structure represented by the general formula (1) is further bonded here. . That is, each line represented by a curve in the formula (1) has a structure represented by the general formula (1). In the present embodiment, the acrylonitrile-butadiene rubber having a branched structure can be, for example, a weight average molecular weight (Mw) of 300,000.

A phenol resin can provide thermosetting, heat resistance, and adhesiveness to the adhesive layer 3. The phenol resin used in this embodiment is not particularly limited, and it is preferably used as a novolac resin that can synthesize phenols and formaldehyde under an acid catalyst. Examples of the phenols include phenol, cresol, xylenol, alkylphenol, halogenated phenol, arylphenol, aminophenol, nitrophenol, bisphenol A, polyphenol, and derivatives thereof. Moreover, these can be used individually or in mixture of 2 or more types.

Peroxide, when thermally followed by heating of the adhesive tape 1, will cause cross-linking of the acrylonitrile-butadiene rubber due to free radicals generated by thermal decomposition. Here, in this embodiment, it is preferable to use a peroxide that generates an acid due to decomposition. That is, if the peroxide is contained in the adhesive layer 3, when the thermal adhesive tape 1 is heated, the curing speed of the adhesive layer 3 can be increased. Specifically, if the heat and adhesive tape 1 of this embodiment are heated, as described above, the peroxide is first thermally decomposed, and the acrylonitrile-butadiene rubber is crosslinked due to the generated free radicals. At this time, the free radicals react with the hydrogen released from the acrylonitrile-butadiene rubber to generate an acid. Then, the reaction of the phenol resin and the phenol resin cross-linking agent is promoted by the acid, and the phenol resin is cross-linked to accelerate the hardening of the phenol resin, thereby increasing the hardening speed of the adhesive layer 3.

On the other hand, the peroxide contained in the adhesive layer 3 of this embodiment is difficult to decompose and hard to generate acid when the thermal adhesive tape 1 is not heated under a room temperature environment or the like. In addition, the peroxide itself does not directly affect the reaction of the phenol resin. Therefore, when the thermal adhesive tape 1 is not heated, the phenol resin is hardly hardened.

The half-life temperature of the peroxide is 130 ° C or higher and 170 ° C or lower. Here, the "half-life temperature" refers to a temperature at which the peroxide concentration is reduced to half of the concentration before heating due to decomposition of the peroxide after heating the peroxide for 1 minute.

When the half-life temperature of the peroxide exceeds 170 ° C, the decomposition rate of the peroxide becomes slower when the peroxide is heated and it becomes difficult to generate an acid. In this case, it is difficult to promote the curing of the phenol resin when the heat-adhesive tape 1 is applied. When the half-life temperature of the peroxide is lower than 130 ° C, even when the peroxide is not heated, the peroxide is easily decomposed to generate an acid. In this case, even when the heat-adhesive tape 1 is not heated, such as when the heat-adhesive tape 1 is stored, the phenol resin is easily cured.

In addition, when the acrylonitrile-butadiene rubber is 100 parts by mass in the adhesive layer 3, it is preferable that the peroxide layer contains 0.5 to 5 parts by mass of a peroxide. If the peroxide is less than 0.5 parts by mass, the amount of acid generated by the peroxide is small, and it is difficult to accelerate the curing of the phenol resin when the adhesive tape 1 is heated and heated. In addition, if the peroxide exceeds 5 parts by mass, when the peroxide is not heated, the peroxide will slowly decompose and the amount of acid generated will increase. In this case, even when the heat-adhesive tape 1 is not heated, such as when the heat-adhesive tape 1 is stored, the phenol resin is easily cured.

It is preferred to use dioxin peroxide or a peroxyester as a peroxide that generates an acid due to decomposition. Moreover, in this embodiment, these can be used individually or in mixture of 2 or more types. Dioxin peroxide may be, for example, Nyper (registered trademark) BMT or Peroyl (registered trademark) L manufactured by Nippon Oil Corporation. Examples of the peroxyester include Perbutyl (registered trademark) O and Perbutyl Z manufactured by Nippon Oil Corporation.

When the phenol resin cross-linking agent is heated and adhered to the adhesive tape 1, an addition condensation reaction occurs with the phenol resin to harden the phenol resin in a shorter time. Phenol resin cross-linking agent, also known as phenol resin cross-linking accelerator, hardener. Examples of the phenol resin cross-linking agent include hexamethylenetetramine (hexylamine), methylolmelamine, and methylolurea. Moreover, these can be used individually or in mixture of 2 or more types. In this embodiment, it is preferable to use hexamethylenetetramine (hexylamine).

The adhesive layer 3 may further contain other resins, rubbers, and the like within the scope of the gist of this embodiment. Further, it may further contain a tackifier for improving the coatability when applying a solution for an adhesive layer of a coating liquid described later, and an antifoaming agent for suppressing foaming and suppressing deterioration of appearance.

<The manufacturing method of a heat-adhesive tape> FIG. 2: is a flowchart explaining the manufacturing method of the heat-adhesive tape 1. As shown in FIG. First, a substrate made of a release liner and a nonwoven fabric having a basis weight of 40 g / m ² or less is prepared (step 101: release liner, substrate preparation step).

Next, a solution for an adhesive layer for applying the adhesive layer 3 is prepared (step 102: a solution for producing an adhesive layer). This solution for the adhesive layer is obtained by containing the acrylonitrile-butadiene rubber, phenol resin, peroxide, and phenol resin cross-linking agent described above, and adding these to a predetermined solvent, followed by stirring.

Next, the release liner is coated with a solution for an adhesive layer to form a coating film (step 103). Furthermore, by drying the coating film, an adhesive layer 3a (first adhesive layer) is formed on the release liner (step 104). The steps from step 103 to step 104 can be regarded as a first adhesive layer forming step of applying a solution for an adhesive layer on a release liner to form a first adhesive layer. Next, an adhesive layer 3a (first adhesive layer) is formed on the release liner, and one surface side of the base material 2 is bonded (transferred). (Step 105: bonding step).

Next, the adhesive layer solution is applied on the other surface side of the base material 2 to form a coating film on the other surface side of the base material 2 (step 106). At this time, the solution for an adhesive layer penetrates the opening H of the nonwoven fabric which comprises the base material 2 as demonstrated in FIG. Furthermore, by drying the coating film, an adhesive layer 3b (second adhesive layer) is formed on the other surface side of the substrate 2 (step 107). The steps 106 to 107 can be confirmed as a second adhesive layer forming step of applying a solution for an adhesive layer on the other surface side of the substrate 2 to form a second adhesive layer.

Through steps 103 to 107, bonding layers 3 (adhesive layers 3a, 3b) are formed on both sides of the substrate 2, and a bonding portion 3c is formed in the opening H of the nonwoven fabric as described in FIG. . Here, when the adhesive layer 3b is formed on the substrate 2, the adhesive layer 3b is directly formed on the substrate 2, but another release liner may be formed on the substrate 2 and then transferred to the substrate 2. In addition, the solution for an adhesive layer may be coated on both surfaces of the substrate 2 at the same time to form the adhesive layer 3a and the adhesive layer 3b at the same time. By the above steps, the entire thickness can be 100 μm or more and 250 μm or less, so that the thermal adhesive tape 1 of this embodiment can be manufactured.

According to the form described in detail above, by using the non-woven fabric as the base material 2, the joint portion 3 c is generated in the opening portion H, thereby providing the thermal adhesive tape 1 having sufficient strength against shearing force.

In addition, when the adherend is thermally compression-bonded to the heat-adhesive tape 1, the peroxide contained in the adhesive layer 3 is decomposed to generate an acid, and the acid accelerates the hardening of the phenol resin and the phenol resin crosslinking agent. Therefore, the curing speed of the adhesive layer 3 is increased, and the thermal adhesive tape 1 can be adhered to the adherend in a short time. On the other hand, when the heat-adhesive tape 1 is not heated, the peroxide is not easily decomposed and acid is not easily generated, so the hardening of the adhesive layer 3 is difficult to proceed. Therefore, when the thermal adhesive tape 1 is not stored, the adhesive force of the thermal adhesive tape 1 is not easily lost.

[Examples] (1) Hereinafter, the present invention will be described in detail using examples. The present invention is not limited to these examples as long as the gist thereof is not exceeded.

The thermal adhesive tape 1 shown in FIG. 1 was produced and evaluated. The implementation conditions and evaluation results are shown in Table 1 below. [Production of Thermal Adhesive Tape 1] (Example 1) In this example, as the substrate 2, a non-woven fabric having a unit weight of 5 g / m ² and a thickness of 30 μm was used. The non-woven fabric is made of polyester having a specific gravity of 1.38. Specifically, MilifeT05 (registered trademark) manufactured by JX ANCI Corporation is used.

On the other hand, the adhesive layer 3a is formed on one surface side of the base material 2 as follows. First, ethyl acetate was used as a solvent, and an acrylonitrile-butadiene rubber having a branched structure, a phenol resin, a peroxide, and a phenol resin cross-linking agent were charged into the solvent, and the mixture was stirred and dissolved to prepare a solid. A solution for an adhesive layer having a component concentration of 40% by mass. At this time, as the acrylonitrile-butadiene rubber having a branch structure, Nipol (registered trademark) 1001LG manufactured by Zeon Corporation of Japan was used. As the phenol resin, Tamanol (registered trademark) 531 manufactured by Arakawa Chemical Industries, Ltd. was used. In Tamanol 531, 9% by mass of hexamethylenetetramine (hexylamine) was contained as a phenol resin crosslinking agent. The mass ratio of the acrylonitrile-butadiene rubber having a branched structure to the phenol resin was 100/120. The peroxide is NyperBMT manufactured by Nippon Oil Corporation.

The general formula (2) of the following formula 3 is a structural formula of NyperBMT. The general formula (3) of the following formula 4 is a reaction formula when NyperBMT is thermally decomposed, and is a reaction formula when a benzamidine peroxide having a part of the structure of NyperBMT is decomposed. If the benzamidine peroxide in the general formula (3) is heated, the oxygen-oxygen bond will be cracked to generate 2 equivalents of phenyl radicals relative to the benzamidine peroxide, and each phenyl radical will become benzoic acid. . That is, when benzophenazine peroxide is thermally decomposed, an acid of 2 equivalents with respect to the benzophenazine peroxide is generated. In addition, a benzamyl-m-benzylhydrazine peroxide having a structure of another part of NyperBMT in the general formula (2), if thermally decomposed, will generate Oxide 2 equivalent acid. In addition, if the tolylmethyl peroxide is thermally decomposed between the structures of another part of NyperBMT in the general formula (2), 2 equivalents of the acid relative to the m-tolylmethyl peroxide are generated. That is, if NyperBMT undergoes thermal decomposition, 2 equivalents of acid relative to the NyperBMT are generated. In addition, the half-life temperature of NyperBMT is 131 ° C. When the acrylonitrile-butadiene rubber is 100 parts by mass of the adhesive layer 3, 3 parts by mass of NyperBMT is preferably contained.

Next, a solution for an adhesive layer is applied on a release liner, and dried to form an adhesive layer 3a. Next, the base material 2 is bonded to the adhesive layer 3a. Then, the adhesive layer solution is applied to the other surface side of the base material 2 and dried to form an adhesive layer 3b. The thickness of the entire heat-adhesive tape 1 was 140 μm.制作 The heat-adhesive tape 1 of this embodiment is produced by the above steps.

(Examples 2 to 6) Except that Example 1 was changed as shown in Table 1, a heat-adhesive tape 1 was produced in the same manner as in Example 1. That is, in Examples 2, 3, and 6, the type of the peroxide contained in the adhesive layer 3 was changed. Specifically, in Example 2, Perbutyl O manufactured by Nippon Oil Co., Ltd. was used. The general formula (4) of the following formula 5 is a structural formula of 2-hexylhexyl-tertiary butyl peroxide of Perbutyl O. If the 2-hexylhexyl-tertiary butyl peroxide of general formula (4) is heated, the oxygen-oxygen bond will be cracked to produce 1 equivalent of free radicals, which will become a carboxylic acid. In other words, when Perbutyl O is thermally decomposed, an acid equivalent to the equivalent of Perbutyl O is generated. The half-life temperature of Perbutyl O was 134 ° C. When the acrylonitrile-butadiene rubber is 100 parts by mass of the adhesive layer 3, 3 parts by mass of Perbutyl O is preferred.

In Example 3, Perbutyl Z manufactured by Nippon Oil Co., Ltd. was used. The general formula (5) of the following formula 6 is a structural formula of a tertiary butyl benzamyl peroxide of Perbutyl Z. If the tertiary butyl benzamidine peroxide of general formula (5) is heated, the oxygen-oxygen bond will be cleaved to generate one equivalent of free radicals relative to the tertiary butyl benzamidine peroxide, This radical becomes a carboxylic acid. That is, when Perbutyl Z is thermally decomposed, an acid equivalent to the equivalent of Perbutyl Z is generated. The half-life temperature of Perbutyl Z was 167 ° C. When the acrylonitrile-butadiene rubber is 100 parts by mass in the adhesive layer 3, 3 parts by mass of PerbutylZ is preferably contained.

In Example 6, Peroyl L manufactured by Nippon Oil Co., Ltd. was used. The general formula (6) of the following formula 7 is the structural formula of Peroyl L bis-dodecyl peroxide. If the bis-dodecyl peroxide of general formula (6) is heated, the oxygen-oxygen bond will be cracked to generate 2 equivalents of free radicals relative to the bis-dodecyl peroxide. Become a carboxylic acid. That is, if Peroyl L is thermally decomposed, 2 equivalents of acid with respect to Peroyl L will be generated. The half-life temperature of Peroyl L was 116 ° C below the lower limit. When the acrylonitrile-butadiene rubber is 100 parts by mass of the adhesive layer 3, 3 parts by mass of Peroyl L is preferably contained.

In Examples 4 and 5, the amount of the peroxide contained in the adhesive layer 3 was changed. Specifically, in Example 4, when the acrylonitrile-butadiene rubber was 100 parts by mass, it contained 0.4 parts by mass of NyperBMT. In Example 5, when the acrylonitrile-butadiene rubber was 100 parts by mass, it contained 6 parts by mass of NyperBMT.

(Comparative Examples 1 to 6) Except that Example 1 was changed as shown in Table 1, a heat-adhesive tape 1 was produced in the same manner as in Example 1. That is, in Comparative Example 1, the adhesive layer 3 does not contain a peroxide. In addition, in Comparative Example 2, benzoic acid was used instead of peroxide in the next layer 3. In addition, in Comparative Example 3, Perhexyl (registered trademark) I manufactured by Nippon Oil Co., Ltd. was used as the peroxide. The general formula (7) of the following formula 8 is the structural formula of the tertiary hexyl isopropyl peroxide monocarbonate of Perhexyl I. If the tertiary hexyl isopropyl peroxide monocarbonate in the general formula (7) is heated, free radicals and carbon dioxide are generated, but no acid is generated. The half-life temperature of Perhexyl I was 155 ° C. When the acrylonitrile-butadiene rubber is 100 parts by mass of the adhesive layer 3, it is preferable that 3 parts by mass of Perhexyl I be contained.

[Table 1]

The evaluations of Examples 1 to 6 and Comparative Examples 1 to 3 are the evaluation of the adhesive strength of the thermal adhesive tape before storage (evaluation of the adhesive strength before storage) and the evaluation of the insoluble components of the thermal adhesive tape before storage. (Evaluation of insoluble components before storage). The thermal adhesive tape after storage was evaluated for adhesive strength (evaluation of adhesive strength after storage), and the thermal adhesive tape after storage was evaluated for insoluble components (evaluation of insoluble component after storage).

[Method for evaluating adhesive force before storage] The adhesive force evaluation of the thermal adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3 was performed by applying a shearing force to the thermal adhesive tape, and evaluating the adhesive force. Specifically, two pieces of glass fiber cloth were prepared, and the two pieces of glass fiber cloth were sandwiched with a heat-adhesive tape, and the two pieces of glass fiber cloth were joined by heat-adhesive tape by thermal compression bonding. The thickness of the glass fiber cloth used for the evaluation was 0.17 mm, and the breaking strength was about 300 N / 10 mm. In addition, under the above-mentioned thermal compression bonding conditions, a person who prepares a glass fiber cloth by thermally bonding the tape is prepared. Specifically, it is prepared to press at a temperature of 160 ° C and 1.47Í10 ⁵ N / m ² for 20 seconds, and then heat-bond the glass fiber cloth with an adhesive tape, and a pressure of 170 ° C and 1.47Í10 ⁵ N / m ² . Hold the glass fiber cloth by pressing for 10 seconds with heat and adhesive tape.

Next, the two glass fiber cloths of the produced adherend were stretched at a stretching speed of 200 mm / min. Under this condition, before the glass fiber cloth and the heat-adhesive tape were peeled off, the glass fiber cloth was used. Whether or not it was damaged was evaluated for the adhesive force with respect to the shear force. That is, regarding the adhesive force, before the glass fiber cloth and the thermal adhesive tape are peeled off, when the glass fiber cloth is broken, it indicates that the shear force is greater than the breaking strength of the glass fiber cloth. When peeling occurred, it was evaluated as unsatisfactory.

[Method for evaluating insoluble components before storage] Also, regarding the heat-adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3, the evaluation of the curing speed of the adhesive layer at the time of thermocompression is to evaluate the heat after thermocompression. Then the insoluble component of the tape. Here, the insoluble content of the heat-adhesive tape refers to the ratio of the weight of the components in the heat-adhesive tape that are not dissolved in the solvent to the total weight of the heat-adhesive tape. The product produced by the reaction between osmic acid and phenol resin is insoluble in solvents. Therefore, the more insoluble components of the heat-adhesive tape after thermocompression, the more acid is generated during the thermocompression, and the reaction is presumed to proceed. The greater the amount of acid produced during thermocompression, the faster the hardening rate of the adhesive layer.

A specific evaluation method for the insoluble content of the heat-adhesive tape after thermocompression bonding. First, prepare two release liners made of polyethylene terephthalate, and sandwich the two release liners with heat-adhesive tape. , The two release liners are thermally bonded to each other by thermocompression bonding. The conditions of the thermocompression bonding are the same as those of the thermocompression bonding in the force evaluation before storage. That is, a person who intends to press at 160 ° C and a pressure of 1.47 Í ^{10 5} N / m ² for 20 seconds and a heat-adhesive tape to bond the release liner, and a pressure of 170 ° C and 1.47 Í ^{10 5} N / m ² to press For 10 seconds, the release liner is bonded with heat and tape. For the evaluation of the insoluble components, the heat-adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3 were those without a substrate.

Next, the heat-adhesive tape was peeled from the release liner, and the weight of the heat-adhesive tape after the release liner was peeled off was measured, and the measured value was W1. The weight of the heat-adhesive tape is about 0.1 g to 0.2 g. After that, the hot-adhesive tape was immersed in 10 g to 20 g of methyl ethyl ketone as a solvent, and stirred with a stirring rotor for 24 hours. Next, the solution was filtered using a stainless steel screen to extract the insoluble components of the heat-adhesive tape. Stainless steel screen is 100 mesh. The weight when the screen is not used is regarded as the weight W2. After that, the sieve with the insoluble components of the heat-adhesive tape remaining was dried in an explosion-proof dryer at 80 ° C, and then left to cool. Next, the weight of this screen was measured, and the measured value was W3. On the other hand, insoluble components were calculated from ((W3-W2) / W1) and evaluated. In addition, regarding the heat-adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3, the insoluble content before thermal compression bonding was 0%.

[Method of Evaluating Adhesion After Storage] The thermal adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3 were evaluated for the adhesive strength after a certain period of storage. Specifically, the heat-adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3 were stored in an environment at 80 ° C. for one week after the heat-adhesive tapes were produced. Then, two pieces of glass fiber cloth were bonded by thermal bonding after storage by thermal compression bonding under the same conditions as the method for evaluating the adhesion force before storage, and a shearing force was applied to the two pieces of glass fiber cloth of the adherend, and then Evaluation of adhesion was performed.

[Method for evaluating insoluble components after storage] Furthermore, in order to evaluate the degree of curing of the adhesive layer of the thermal adhesive tape when it is stored without thermal compression bonding, the thermal adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3 were evaluated. And evaluate the insoluble components after storage for a certain period. The more insoluble components after storage of the hot-adhesive adhesive tape, the more acid is generated from the peroxide contained in the adhesive layer during storage, and the reaction is presumed to proceed. The more acid generated during storage, the greater the degree of hardening of the layer before thermocompression bonding.

The specific evaluation method of the insoluble components after storage of the heat-adhesive tape is the heat-adhesive tapes of Examples 1 to 6 and Comparative Examples 1 to 3. After the heat-adhesive tapes are manufactured, they are stored in an environment of 80 ° C. For one week, the weight of the heat-adhesive tape after storage was regarded as W4. After that, the insoluble content of the heat-adhesive tape was extracted using a stainless steel screen by the same method as the insoluble content evaluation method before storage. Among them, the evaluation of insoluble components after storage is used to evaluate the amount of acid generated during storage, which is different from the evaluation of insoluble components before storage, and extracts the insoluble components of the heat-adhesive tape that has not been heat-pressed. The weight of the sieve when it is not used is taken as the weight W5, and the weight of the sieve with the remaining insoluble content of the heat-adhesive tape is taken as the weight W6. The insoluble content is calculated from ((W6-W5) / W4) and evaluated.

[Evaluation Results] Table 1 shows the evaluation results of adhesion. As shown in Table 1, regarding the thermal adhesive tapes 1 of Examples 1 to 6, regardless of the conditions under which the producers were thermocompression-bonded, the adhesive force before storage and the adhesive force after one week of storage were all acceptable. In addition, regarding the thermal adhesive tapes 1 of Examples 1 to 6, the insoluble component before storage was greatly increased regardless of the conditions for the thermal compression bonding of the maker, and it is estimated that the curing of the adhesive layer during thermal compression bonding was promoted. In addition, the increase in the insoluble content of the heat-adhesive tape after one week of storage is suppressed, and it is presumed that curing of the adhesive layer becomes difficult to proceed during storage.

In contrast, in Comparative Examples 1 and 3, regarding the thermal adhesive tape before storage, the adhesive layer was aggregated and broken to cause the thermal adhesive tape to peel off. In Comparative Examples 1 and 3, the heat-adhesive tape before storage had almost no increase in insoluble content after thermocompression bonding. In this regard, in Comparative Example 1, no peroxide was originally used, and in Comparative Example 3, although peroxide was used, no acid generated by decomposition of the peroxide was generated. Therefore, in Comparative Examples 1 and 3, no acid was generated during the thermal compression bonding of the heat-adhesive tape, and the crosslinking of the phenol resin did not proceed sufficiently, and the curing of the adhesive layer was insufficient. Therefore, it is estimated that it cannot be obtained The sufficient adhesive force of the thermal adhesive tape to the adherend.

Moreover, in Comparative Example 2, the adhesive force of the thermal adhesive tape before storage was acceptable, but the thermal adhesive tape after one week of storage caused interface breakage in the adherend and peeled off the thermal adhesive tape. In Comparative Example 2, the insoluble content of the heat-adhesive tape before storage was significantly increased after compression and compression, but the insoluble content of the heat-adhesive tape after storage for one week also increased significantly. It is presumed that the phenol resin was cross-linked due to the reaction between benzoic acid and the phenol resin during storage of the thermal adhesive tape for one week, and the curing of the adhesive layer proceeded. After hardening of the adhesive layer is sufficiently performed, even if the adherend is thermally compression-bonded to the thermal adhesive tape, a sufficient adhesive force of the thermal adhesive tape to the adherend cannot be obtained.

Based on the results of Examples 1 to 6 and Comparative Examples 1 to 3, it was confirmed that the adhesive layer 3 on the thermal adhesive tape 1 must contain a peroxide that generates an acid due to decomposition.

1‧‧‧Heat Adhesive Tape

2‧‧‧ substrate

3, 3a, 3b

3c‧‧‧Joint

H‧‧‧ opening

FIG. 1 is a cross-sectional view showing a heat-adhesive tape used in this embodiment. FIG. 2 is a flowchart illustrating a method of manufacturing a heat-adhesive tape.

Claims (5)

A heat-adhesive tape, which is a heat-adhesive tape that is bonded to an adherend by thermal compression bonding, and includes: a substrate made of a non-woven fabric; and an adhesive layer provided on one side of the substrate and the other Each surface side of the side contains acrylonitrile-butadiene rubber, a phenol resin, a peroxide that generates an acid due to decomposition, and a phenol resin crosslinking agent. The heat-adhesive tape according to claim 1, wherein the half-life temperature of the aforementioned peroxide is 130 ° C or higher and 170 ° C or lower. The hot-adhesive tape according to claim 1 or 2, wherein when the acrylonitrile-butadiene rubber is 100 parts by mass, the adhesive layer contains 0.5 to 5 parts by mass of the peroxide. The heat-adhesive tape according to any one of claims 1 to 3 has a thickness of 100 μm or more and 250 μm or less as a whole. A method for manufacturing a heat-adhesive tape includes the following steps: (1) a release liner and a substrate preparation step: preparing a substrate composed of a release liner and a non-woven fabric; and (2) a step for preparing a solution for an adhesive layer: producing acrylonitrile-butane A solution for an adhesive layer of an olefin rubber, a phenol resin, a peroxide that generates an acid due to decomposition, and a phenol resin cross-linking agent. (1) A first adhesive layer forming step: applying the solution for the adhesive layer to the release liner, to Forming a first adhesive layer, bonding step: bonding one surface side of the substrate to the first bonding layer formed by the release liner, and second bonding layer forming step: coating the bonding layer with a solution A second adhesive layer is formed on the other surface side of the aforementioned substrate.