KR100598935B1 - Flame retardant pressure-sensitive adhesive tape - Google Patents

Abstract

In order to provide a odorless flame-retardant pressure-sensitive adhesive tape composed of a substrate that does not corrode or discolor the adherend and does not emit halogen gas or sulfurous acid gas that is harmful to the environment upon incineration, the odorless non-halogen flame-retardant pressure-sensitive adhesive whose substrate is woven. The tape is described. The pressure-sensitive adhesive tape is preferably a woven fabric substrate, a vulcanized natural rubber flame retardant composition layer applied to the surface of the substrate, and a vulcanized natural rubber flame retardant pressure-sensitive adhesive layer (both of which are tackifier resins, flame retardants (metal hydroxides and inorganics). Flame retardant) and natural rubber-based elastomer vulcanized with aminoalkylalkoxysilane. It is preferable that the said board | substrate is a flameproofed woven fabric board obtained by penetrating a natural rubber type flameproof composition to a flammable woven board substrate.

Description

Flame retardant pressure-sensitive adhesive tape {FLAME RETARDANT PRESSURE-SENSITIVE ADHESIVE TAPE}

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view of a flame-retardant pressure-sensitive adhesive tape in which a substrate is a woven fabric comprising one layer of flame-retardant composition layer and one layer of flame-retardant pressure-sensitive adhesive layer.

2 is a cross-sectional view of a flame-retardant pressure-sensitive adhesive tape in which a substrate is a woven fabric including two layers of flame-retardant composition layers and one layer of flame-retardant pressure-sensitive adhesive layer.

FIG. 3 is a cross-sectional view of a flame-retardant pressure-sensitive adhesive tape having a woven fabric in which one side of the substrate includes a flame retardant composition layer and a flame retardant pressure-sensitive adhesive layer, and the other side of the substrate further includes a flame retardant composition layer.

The present invention can be used for electrical and electronic parts and electrical equipment parts, does not discolor the adherend, does not emit a gas that adversely affects the environment upon incineration of unnecessary waste tape, such as halogen gas or sulfurous acid gas, preferably It is related with the odorless flame-retardant pressure-sensitive adhesive tape in which a board | substrate becomes a woven fabric.

The pressure-sensitive adhesive tapes, which have been used for electrical and electronic components so far, for which the substrate is a woven fabric, have the flexibility and the dustproofness of the woven substrate, not to mention electrical insulation and electrical corrosion resistance. By making good use of adhesiveness, it is widely used to bind and fix a complex shape adherend, or to fix a noise generating site | part. Pressure-sensitive adhesive tapes for this purpose generally need to have a flame retardant level established by UL510FR. In a pressure-sensitive adhesive tape in which a substrate is a woven fabric, the volume of the woven fabric as a combustion source is large, and the flame retardancy is poor due to the large amount of air contained in the fibers constituting the woven fabric. Therefore, flame retardance is imparted by mix | blending a large amount of halogen containing flame retardant with a high flameproof effect in a pressure sensitive adhesive agent with an antimony flame retardant adjuvant, or providing a flameproof layer separate from a pressure-sensitive adhesive layer.

As the pressure-sensitive adhesive used at this time, vulcanized rubber-based pressure-sensitive adhesives are widely used because the adhesive has good adhesive performance to various adherends at the time of initial bonding, electrical insulation and the like. This is because more thermal properties are given.

In recent years, halogen-based flame retardants that generate halogen gas at incineration, antimony-based flame retardants containing lead and arsenic, and the like have been regulated for the purpose of environmental protection. It not only releases sulfurous acid or nitrogen oxides upon incineration, but also contains sulfur and thiuram, which are used for vulcanization of rubber, which is the main component of pressure-sensitive adhesive, because they are carcinogenic substances. Is being processed. Therefore, flame-retardant pressure-sensitive adhesive tapes having a woven substrate using these materials are also forced to cope with these regulations.

Occasionally, a flame-retardant pressure-sensitive adhesive tape containing these materials and the substrate is a woven fabric may corrode the adherend, discolor the adherend of organic fibers such as paper or woven fabric, or may cause an unpleasant odor peculiar to a halogen flame retardant. There is a drawback that occurs.

As an alternative to these halogen-based flame retardants, a urea compound (see Japanese Laid-Open Patent Publication No. 2001-81419), an organophosphorus compound (Japanese Laid-Open Patent Publication) in a pressure-sensitive adhesive layer or a substrate layer of a pressure-sensitive adhesive tape 2000-169811), red phosphorus (Japanese Unexamined Patent Publication No. 8-193187), aluminum hydroxide (Japanese Patent Application No. 2000-314960) or magnesium hydroxide (Japanese Unexamined Patent Publication No. 2001-2839) Methods are known. However, no effective means has been found for pressure-sensitive adhesive tapes in which the substrate is woven in nature.

In order to produce a flame-retardant pressure-sensitive adhesive tape in which a substrate having a flameproof level according to UL510FR is woven such that the continuous combustion time is less than 60 seconds, a large amount of the aforementioned metal hydroxides must be added to the pressure-sensitive adhesive. However, this method is difficult to maintain pressure-sensitive adhesiveness, and has a drawback of poor contact adhesion to a woven substrate. Non-halogen-based organic flame retardants such as urea or melamine compounds (e.g., melamine sulfate) have a problem of low moisture resistance or poor thermal stability, in addition to an increase in the amount of addition, or the organic flame retardants are water-soluble, thus promoting ion elution. It may also cause electrical corrosion problems due to activity. Therefore, it is not a suitable material. The organophosphorus compound has problems such as generation of phosphorus compounds upon incineration of the pressure-sensitive adhesive tape or adverse effects on the environment during waste disposal.

The pressure-sensitive adhesive used for the flame-retardant pressure-sensitive adhesive tape whose substrate is a woven fabric is generally a rubber-based pressure-sensitive adhesive, but this adhesive lacks heat resistance or solvent resistance as compared to pressure-sensitive adhesives such as acrylic and silicone. In order to solve this problem, vulcanizing agents such as sulfur, vulcanizing agents such as compounds, peroxides, oximes, phenol resins or maleimide, vulcanizing accelerators such as thioram or zinc oxide, etc. are used in the form of a mixture. The reaction is widely performed. However, such pressure sensitive adhesives cause metal corrosion or discoloration, have a short usable period of the compounding material, take a long time to vulcanize, and still cause problems of oxygen inhibiting action during vulcanization.

In addition, sulfurous acid gas generated during incineration of the vulcanized pressure-sensitive adhesive may cause environmental problems, or thioram, which is used as a vulcanization accelerator, should be handled with the utmost care because it is an environmental pollutant, or carcinogenic when decomposed. Since nitrosamine is produced, it is regulated by the PRTR method (Japan).

In order to solve this problem, rubber vulcanization reaction systems using aminoalkylalkoxysilanes have been proposed. As a publication relating to the technology of this vulcanization reaction system, a paper reporting that a coupling agent to which an amino group is bonded is effective for halogenated rubber [S. Yamashita, M. Shigaraki, M. Orita and RC Caoutch, Plast. , 606, 126 (1986)], which reports that the coupling agent is more efficient for epoxidized rubber during heat treatment [M. Akiba and AS Hashim, Prog. Polym. Sci. , 22, 475 (1997)], which reports that rubbers without functional groups or double bonds can be vulcanized with vinyl silanes in systems using mixtures with peroxides [M. Akiba and AS Hashim, Prog. Polym. Sci . , 22, 475 (1997).

On the other hand, with respect to general-purpose rubbers such as natural rubber or SBR, a method of bonding a filler treated with a sulfur-containing coupling agent to a rubber molecular chain in a conventional vulcanization method is introduced. Hiroshi Okamoto, Nippon Gomkyo Kaishi, 62, 819 (1998) and the like, but there is no report on the vulcanization technology of natural rubber by aminoalkylalkoxysilane itself.

Moreover, as a problem inherent to the flame-retardant pressure-sensitive adhesive tape in which the substrate is a woven fabric, the contact adhesive force between the substrate and the pressure-sensitive adhesive may be poor, or the pressure-sensitive adhesive may leak out of the coating film. In some cases, electrical corrosion or the like may occur due to the ionic sizing agent used at the time of weaving the woven fabric substrate.

It is an object of the present invention to provide an odorless flame retardant pressure-sensitive adhesive tape which does not corrode or discolor the adherend and does not emit halogen gas or sulfurous acid gas that is harmful to the environment upon incineration.

Summary of the Invention

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched in order to solve these problems, and, as a result, the natural rubber type elastomer which vulcanized the natural rubber type elastomer with the terminal amino group containing aminoalkyl alkoxysilane, and vulcanized with the said aminoalkyl alkoxysilane, preferably has a metal hydroxide and When applying a vulcanized natural rubber flame retardant pressure-sensitive adhesive obtained by mixing with an inorganic flame retardant prepared by an inorganic flame retardant to a substrate, even if a flammable woven substrate is used, an odorless non-sulfur / non-halogen flame retardant It has been found that adhesive tapes can be provided. The present invention has been completed based on this finding. The present invention includes the following inventions.

(1) a woven fabric substrate and a flame-retardant pressure-sensitive adhesive layer on at least one main surface of the woven fabric substrate, the flame-retardant pressure-sensitive adhesive layer includes a natural rubber elastomer containing 50% by weight or more of natural rubber components, an aminoalkylalkoxysilane as a vulcanizing agent, A flame-retardant pressure-sensitive adhesive tape, comprising a tackifier resin and an inorganic flame retardant, wherein the natural rubber elastomer is vulcanized with an aminoalkylalkoxysilane and meets the flame retardant level established by UL510FR.

(2) In the flame-proof pressure-sensitive adhesive tape according to (1), the flame-proof pressure-sensitive adhesive tape further comprises a flame-retardant composition layer on the substrate side of the flame-retardant pressure-sensitive adhesive layer, the flame-retardant composition layer is 50% by weight or more of the natural rubber component It is composed of a natural rubber-based elastomer and a vulcanizing agent aminoalkylalkoxysilane and an inorganic flame retardant, the natural rubber-based elastomer is vulcanized with an aminoalkyl alkoxysilane, the content of the flame retardant in the flame retardant composition layer is higher than the content of the flame retardant in the flame-retardant pressure-sensitive adhesive layer. Flame-proof pressure-sensitive adhesive tape.

(3) In the flame retardant pressure-sensitive adhesive tape according to (1) or (2), the woven substrate is penetrated by the flame retardant pressure-sensitive adhesive layer or the flame retardant composition layer, whereby the substrate is penetrated in the penetrated flame retardant pressure-sensitive adhesive layer or flame retardant composition layer. Flame-proof pressure-sensitive adhesive tape that is embedded.

(4) The flameproof pressure-sensitive adhesive tape according to (1) to (3), wherein the woven fabric substrate has a second surface opposite to the flameproof pressure-sensitive adhesive layer, and another flame-retardant composition layer is applied to the second surface. Flame-proof pressure-sensitive adhesive tape.

(5) The flameproof pressure-sensitive adhesive tape according to (1) to (4), wherein the inorganic flameproof agent is composed of a metal hydroxide and an inorganic flameproofing aid.

(6) The flame retardant pressure-sensitive adhesive tape according to (1) to (5), wherein the flame retardant composition layer further contains a tackifier resin, wherein the weight ratio of the tackifier resin to the natural rubber elastomer in the flame retardant composition layer is flame retardant. A flame-retardant pressure-sensitive adhesive tape having a higher ratio than the weight ratio in the pressure-sensitive adhesive layer.

(7) The flameproof pressure-sensitive adhesive tape according to (1) to (6), wherein the woven substrate is a flammable woven fabric.

(8) The flameproof pressure-sensitive adhesive tape according to (1) to (7), wherein the aminoalkylalkoxysilane is contained in each of the flameproof pressure-sensitive adhesive layer or the flameproof composition layer at a ratio of 0.1 to 10 parts by weight per 100 parts by weight of the natural rubber elastomer. Flame-proof pressure-sensitive adhesive tape.

(9) Flame retardant pressure-sensitive adhesive tape according to (1) to (8), wherein the content of the inorganic flame retardant is more than 150 parts by weight and 800 parts by weight per 100 parts by weight of the natural rubber-based elastomer in the flame retardant pressure-sensitive adhesive layer or the flame retardant composition layer. Adhesive tape.

(10) The flame-retardant adhesive tape according to (1) to (9), wherein the flame-retardant pressure-sensitive adhesive layer contains 10 to 200 parts by weight of a tackifier resin per 100 parts by weight of the natural rubber elastomer, and the flame retardant composition layer is 100 parts by weight of the natural rubber elastomer. The blending ratio of the tackifier resin to the elastomer contained in the flame retardant composition layer is 10-200 parts by weight of an unfair tackifier resin, and is higher than that of the tackifier resin contained in the flame-retardant pressure-sensitive adhesive layer. Flame-proof pressure-sensitive adhesive tape.

(11) In the flame-proof pressure-sensitive adhesive tape according to (2) to (10), the flame-retardant composition layer is composed of two or more layers of flame-retardant composition layers, and is an adhesive contained in the flame-retardant composition layer in contact with the flame-retardant pressure-sensitive adhesive layer. The flame-proof pressure-sensitive adhesive tape in which the blending ratio of the imparting agent resin to the elastomer is higher than the blending ratio of the imparting agent resin to the elastomer contained in the flame-retardant pressure-sensitive adhesive layer.

(12) The flameproof pressure-sensitive adhesive tape according to (1) to (11), wherein the inorganic flameproof agent contains aluminum hydroxide and / or magnesium hydroxide.

(13) The flame retardant pressure-sensitive adhesive tape according to (1) to (12), wherein the flame retardant contains one or more selected from the group consisting of tin oxide, zinc meta-stannate, zinc hydroxytinate, and zinc borate. Flame retardant pressure sensitive adhesive tape.

(14) The flame retardant pressure-sensitive adhesive tape according to (1) to (13), wherein the aminoalkylalkoxysilane is N-β (aminoethyl) γ -aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ- Aminopropylmethyldiethoxysilane, N-β (aminoethyl) γ -aminopropyltrimethoxysilane, N-β (aminoethyl) γ -aminopropyltriethoxysilane, γ -aminopropyltrimethoxysilane and γ- Flame retardant pressure-sensitive adhesive tape selected from the group consisting of aminopropyltriethoxysilane.

(15) The flame retardant pressure-sensitive adhesive tape according to (1) to (14), wherein the flame retardant pressure-sensitive adhesive layer and / or flame retardant composition layer is at least one component selected from the group consisting of inorganic fillers, ultraviolet absorbers, antioxidants and oils. Flame-proof pressure-sensitive adhesive tape that further contains.

(16) The flame-proof pressure-sensitive adhesive tape according to the above (1) to (15), wherein the coating amount of the flame-retardant composition layer is 3 to 250 g / m 2.

(17) The flame-proof pressure-sensitive adhesive tape of (1) to (16), wherein the amount of the flame-proof pressure-sensitive adhesive layer is 20 to 600 g / m 2.

(18) In the flame-retardant pressure-sensitive adhesive tape according to (1) to (17), the flammable woven fabric is a single yarn containing fibers selected from the group consisting of staple fibers, cotton, polyester, polyethylene, polypropylene, and acrylic fibers ( Iv) or a short-fiber or interwoven fabric woven from blended yarns, both warp and weft thicknesses of 38 to 300 deniers, and fiber density of 25 to 450 yarn / inch.

(19) The flame retardant pressure-sensitive adhesive tape according to (1) to (18), wherein the flame retardant pressure-sensitive adhesive layer and / or flame retardant composition layer do not contain sulfur and halogen.

(20) A woven substrate comprising a flame retardant composition layer and a flame retardant pressure-sensitive adhesive layer sequentially on at least one major surface, the woven substrate being penetrated and applied by the flame retardant composition layer, wherein the flame retardant composition layer comprises a natural rubber component. It is composed of a natural rubber elastomer containing at least 50% by weight, an aminoalkyl alkoxysilane, a tackifier resin, a flame retardant containing a metal hydroxide and an inorganic flame retardant, and the natural rubber elastomer is vulcanized by an aminoalkylalkoxysilane, which is amino The alkylalkoxysilane is blended at a ratio of 0.1 to 10 parts by weight per 100 parts by weight of the natural rubber elastomer, and the flame retardant pressure-sensitive adhesive layer is a natural rubber elastomer, an aminoalkylalkoxysilane, a tackifier resin, a metal containing at least 50% by weight of the natural rubber component. Flame retardant containing hydroxide and inorganic flame retardant Wherein the natural rubber elastomer is vulcanized with aminoalkylalkoxysilane, the aminoalkylalkoxysilane is formulated at a ratio of 0.1 to 10 parts by weight per 100 parts by weight of the natural rubber elastomer, and meets the flame resistance level established by UL510FR. Flame-proof pressure-sensitive adhesive tape characterized in.

(21) In the flame retardant pressure-sensitive adhesive tape according to (20), the ratio of the inorganic flame retardant to be blended with the metal hydroxide in each layer of the flame retardant composition layer and / or the flame retardant pressure-sensitive adhesive layer is 10 to 50 parts by weight per 100 parts by weight of the metal hydroxide. And the total amount of the metal hydroxide and the inorganic flame retardant aid is more than 150 parts by weight and 800 parts by weight per 100 parts by weight of the natural rubber-based elastomer in the flame retardant pressure-sensitive adhesive layer or flame retardant composition layer, and does not contain sulfur, antimony, lead, arsenic, phosphorus, and halogen. Flame-proof pressure-sensitive adhesive tape to be.

(22) Use of the flame-retardant pressure-sensitive adhesive tape according to (1) to (21) as a television component or a deflection coil.

In order to avoid the use of flame retardants containing halogen, antimony, lead or arsenic, which produce odors or harmful gases to the environment, metal hydroxides are candidates as alternative flame retardants without such harmful effects.

Metal hydroxides, which are preferably used for odorless non-halogen flame retardant pressure-sensitive adhesive tapes having a woven substrate, exhibit dehydration reactions due to temperature rise during ignition and exhibit self-extinguishing properties. When a large amount is added to the pressure-sensitive adhesive layer of, there is a problem that the pressure-sensitive adhesiveness is impaired. However, the inventors have found that the natural rubber elastomer may be vulcanized by aminoalkylalkoxysilane, and when the natural rubber elastomer vulcanized by the aminoalkylalkoxysilane is used in the pressure sensitive adhesive, an inorganic flame retardant such as a metal hydroxide may be added to the pressure sensitive adhesive layer. It has been found that even when a large amount of the inorganic flame retardant composed of the inorganic flame retardant is added, excellent pressure-sensitive adhesiveness is obtained.

Until now, resin compositions using natural rubber-based elastomers without functional groups can be vulcanized by aminoalkylalkoxysilanes or natural rubber-based elastomers vulcanized by pressure-sensitive adhesives or aminoalkylalkoxysilanes as metal hydroxides and inorganic flame retardant agents. It has not been known to exhibit excellent properties of having a uniformly formulated inorganic flame retardant and to have excellent contact adhesion to an adherend or a woven substrate. According to the present invention, even when the inorganic flame retardant is blended in a large amount in the pressure-sensitive adhesive layer or the resin composition, it is possible to achieve a predetermined adhesive force such as contact adhesiveness to an adhesive or a woven fabric substrate and the adhesive strength (peel adhesion force) of the pressure-sensitive adhesive.

 Since no sulfur or thiol group (-SH) is required for the vulcanization reaction, preferred aminoalkylalkoxysilanes can vulcanize natural rubber elastomers.

The flame-retardant pressure-sensitive adhesive in the pressure-sensitive adhesive tape of the present invention is a natural rubber-based elastomer in which components such as tackifier resins, oils, fillers, antioxidants, flame retardants composed of metal hydroxides, flame retardant aids and the like are vulcanized with aminoalkylalkoxysilanes. It can obtain by mix | blending. The flame-retardant pressure-sensitive adhesive in the pressure-sensitive adhesive tape of the present invention can be vulcanized using low energy, has no oxygen inhibiting action, does not corrode odorless and adherent metal, or discolor paper, woven fabric, or plastic.

In a preferred embodiment of the present invention, the flame retardant composition layer is provided on the substrate side of the flame retardant pressure-sensitive adhesive layer, that is, between the flame retardant pressure-sensitive adhesive layer and the woven substrate, and inside or outside the woven substrate as necessary. The flame retardant composition layer is composed of a natural rubber elastomer, an aminoalkylalkoxysilane, a tackifier resin, and an inorganic flame retardant, and the natural rubber elastomer is vulcanized with an aminoalkylalkoxysilane. The content of the inorganic flame retardant in the flame retardant composition layer is preferably higher than the content of the flame retardant pressure-sensitive adhesive layer. With this configuration, the amount of flame retardant in the flame retardant pressure-sensitive adhesive layer required to obtain flame retardant level of the tape meeting the UL510FR combustion test standard can be reduced, while the pressure-sensitive adhesive property of the pressure-sensitive adhesive layer contains a relatively small amount of inorganic flame retardant in the flame-retardant pressure-sensitive adhesive layer. This can be kept high. By combining the flame-retardant pressure-sensitive adhesive layer and the flame-retardant pressure-sensitive adhesive layer described in the above preferred embodiment of the present invention, both excellent pressure-sensitive adhesiveness and high flameproof level can be easily satisfied. The flame retardant composition layer may be composed of the same composition as the flame retardant pressure-sensitive adhesive layer, but the content of the flame retardant in the flame retardant composition layer is advantageously higher than that of the pressure-sensitive adhesive layer.

The flame-retardant pressure-sensitive adhesive tape obtained by forming a flame-retardant pressure-sensitive adhesive layer provided with a flame-retardant composition layer on at least one side of the substrate as needed, the substrate is a woven fabric, the flame-retardant pressure-sensitive adhesive tape has the flexibility and adhesiveness inherent in the rubber-based pressure-sensitive adhesive and rubber-based resin, It is excellent in odor and odorless, and does not emit halogen gas or sulfurous acid gas that is harmful to the environment upon incineration of the pressure-sensitive adhesive tape. By using a woven fabric, particularly a flammable woven fabric such as a cotton cloth, as the substrate, the pressure-sensitive adhesive tape can have excellent flexibility inherent to the woven fabric.

In a preferred embodiment of the present invention, the woven substrate is subjected to a flame retardant treatment by penetrating a natural rubber flame retardant pressure-sensitive adhesive or a natural rubber flame retardant composition containing a flame retardant, a tackifier, and an aminoalkylalkoxysilane when used. In addition, by the penetration flameproof treatment of the woven fabric substrate, the amount of the flame retardant in the pressure-sensitive adhesive layer required to obtain the flameproof level of the tape satisfying the UL-510FR combustion test standard can be reduced. According to the above penetration treatment, the sizing agent adhered to the woven fabric due to the coating treatment can be fixed, and excellent electrical anticorrosiveness can be obtained without performing a refining treatment. In addition, since the flame retardant pressure-sensitive adhesive or flame retardant composition penetrates into the woven fabric substrate (as a result, application of the entire surface or part of the surface of the woven fabric), the flame retardant effect on combustion is exerted from the substrate side (exposure side) of the flame retardant pressure-sensitive adhesive tape. .

According to the present invention, an additional anti-flame layer, preferably a natural rubber-based flame retardant composition layer containing a flame retardant, a tackifier resin and an aminoalkylalkoxysilane, is provided on the side of the substrate opposite the pressure-sensitive adhesive layer, thereby It is generally possible to improve the flame resistance of adhesive tapes, especially adhesive tapes on which the substrate is combustible. This flameproof treatment may be to infiltrate the flameproof pressure-sensitive adhesive or flameproof composition into the inside of the woven fabric substrate, or may be to apply a flameproof layer to the surface of the woven fabric substrate on the exposed surface side. In addition, the composition of the flame retardant layer may be the same as or different from the flame retardant pressure-sensitive adhesive layer or the flame retardant composition layer.

EMBODIMENT OF THE INVENTION Hereinafter, the odorless non-halogen flame-proof pressure-sensitive adhesive tape which concerns on this invention is demonstrated with reference to drawings.

1 is a cross-sectional view of a flame retardant pressure-sensitive adhesive tape in which a substrate is a woven fabric, and includes one layer of flame retardant composition layer and one layer of flame retardant pressure-sensitive adhesive layer. Fig. 2 is a cross-sectional view of the flame-retardant pressure-sensitive adhesive tape in which the substrate is a woven fabric, and includes two layers of a flame-retardant pressure-sensitive adhesive layer and one layer of a flame-retardant pressure-sensitive adhesive layer.

1 and 2, reference numeral 1 is, for example, a flammable woven fabric, 2 is a natural rubber flame retardant composition layer composed of an inorganic flame retardant such as a metal hydroxide, an inorganic flame retardant, and an aminoalkylalkoxysilane, and 3 is an aminoalkylalkoxy It is a natural rubber flame-proof pressure-sensitive adhesive layer composed of inorganic flame retardants such as natural rubber elastomers and metal hydroxides vulcanized using silane and inorganic flame retardant. The natural rubber-based flame retardant composition layer 2 is permeated into the inside of the woven substrate 1 (but it is not necessary to penetrate), and preferably the surface of the woven substrate 1 on the opposite side to the natural rubber-based flame retardant pressure-sensitive adhesive layer 3 is It is good to apply the whole surface of the woven substrate 1 including. In Fig. 2, reference numeral 4 is an additional vulcanized natural rubber flame retardant composition layer, which is applied between the natural rubber flame retardant composition layer 2 and the vulcanized natural rubber flame retardant pressure-sensitive adhesive layer 3.

As shown in Fig. 1 and Fig. 2, in the preferred embodiment of the present invention, the content of the flame retardant in the natural rubber-based flame retardant composition layer 2 or, if used, the natural rubber-based flame retardant composition layer 4, is natural rubber-based. The flame retardant pressure-sensitive adhesive layer 3 is designed to be more than the content of the flame retardant. In FIG. 3, the flame-retardant pressure-sensitive adhesive tape has a natural rubber-based flame retardant composition layer 2 on one side of the woven substrate 1, a natural rubber-based flame-retardant pressure-sensitive adhesive layer 3, and an additional flame-retardant layer 6 on the opposite side of the woven substrate. In particular, it contains a natural rubber-based flame retardant layer. The additional flame retardant layer 6 preferably includes, but is not limited to, natural rubber-based elastomers vulcanized with aminoalkylalkoxysilanes, tackifier resins and inorganic flame retardants such as metal hydroxides and inorganic flame retardant auxiliaries. Any flame retardant may be provided as long as it provides flame retardance to the exposed surface.

In the rubber elastomer used for the natural rubber flame retardant composition layer and the vulcanized natural rubber flame retardant pressure-sensitive adhesive layer, the natural rubber component preferably occupies at least 50% by weight, more preferably 60% by weight or even 100% by weight. do. As elastomers other than natural rubber, synthetic rubbers, such as butyl rubber, isoprene rubber, butadiene rubber, and acrylic rubber, can be used alone or as a mixture of two or more thereof. It is preferable to completely exclude the rubber component containing a halogen. If the natural rubber component is less than 50% by weight, the crosslink density by vulcanization using an aminoalkylalkoxysilane will not be sufficient, and thus the holding force at the time of heating will not be high enough. Natural rubber has the advantage that does not emit halogen gas and the like harmful to the environment during incineration.

In the present invention, since aminoalkylalkoxysilane is used as a vulcanizing agent of a natural rubber elastomer, sulfurous acid gas is not generated during incineration, unlike ordinary sulfur vulcanizing agents. It is one of the advantages of the present invention that there is no need to substantially use harmful vulcanizing agents such as sulfur.

Aminoalkylalkoxysilanes not only act as vulcanizing agents of natural rubber elastomers, but also function as coupling agents for inorganic flame retardants and coupling agents for woven substrates or adherends.

Preferred aminoalkylalkoxysilanes are N-β (aminoethyl) γ -aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ -aminopropylmethyldiethoxysilane, N-β (aminoethyl) γ -aminopropyltri trimethoxysilane, N-β (aminoethyl) γ - on aminopropyl triethoxysilane, γ - aminopropyltrimethoxysilane, and γ - and the aminopropyl silane, represented by the following structural formula.

H ₂ NC ₂ H ₄ -NH-C ₃ H ₆ -SiCH ₃ (OCH ₃ ) ₂

H ₂ NC ₂ H ₄ -NH-C ₃ H ₆ -SiCH ₃ (OC ₂ H ₅ ) ₂

H ₂ NC ₂ H ₄ -NH-C ₃ H ₆ -Si (OCH ₃ ) ₃

H ₂ NC ₂ H ₄ -NH-C ₃ H ₆ -Si (OC ₂ H ₅ ) ₃

H ₂ NC ₃ H ₆ -Si (OCH ₃ ) ₃

H ₂ NC ₃ H ₆ -Si (OC ₂ H ₅ ) ₃

The amount of the aminoalkylalkoxysilane added is preferably 0.1 to 10 parts by weight per 100 parts by weight of the natural rubber elastomer. If the amount is less than 0.1 part by weight, the vulcanization reaction proceeds incompletely, and as a result, the coating film strength of the vulcanized natural rubber-based flame retardant composition layer or flame-retardant pressure-sensitive adhesive layer sufficiently formed on the surface of the substrate or penetrated into the substrate is sufficient. It is not high, the contact adhesion to the substrate is weak, and the holding force at heating is insufficient due to the incomplete vulcanization reaction.

The amount of aminoalkylalkoxysilane used in the present invention is generally higher than that of the vulcanizing agent in the corresponding conventional composition.

When the amount of the aminoalkyl alkoxysilane added is more than 10% by weight, in the case of the natural rubber-based flame retardant composition layer, there is a problem that the coating film after vulcanization is excessively hardened to lose the feel of the woven fabric, and the vulcanized-treated natural rubber-based flame retardant In the case of the pressure-sensitive adhesive layer, a problem arises in that the adhesive strength decreases over a steady state or over time due to the overvulcanization reaction.

The flame retardant of the present invention preferably contains a metal hydroxide and an inorganic flame retardant, but is not limited thereto. For example, the metal hydroxide depends on other factors such as the type of substrate, the composition of the flame retardant composition, and the composition of the flame-retardant pressure-sensitive adhesive layer. And only one of inorganic flame retardant preparations may be used.

The amount of the flame retardant is preferably more than 150 parts by weight and 800 parts by weight per 100 parts by weight of the natural rubber elastomer of the adhesive tape, more preferably 300 to 800 parts by weight.

The blending ratio of the metal hydroxide and the inorganic flame retardant is preferably such that when they are added, the amount of the flame retardant is 10 to 50 parts by weight per 100 parts by weight of the metal hydroxide. If the flame retardant is less than 10 parts by weight, the flame retardant effect by the metal hydroxide is reduced, while if the flame retardant is more than 50 parts by weight, the flame retardant effect by the addition of the flame retardant is not exerted.

The amount of flame retardant containing a mixture of metal hydroxide and flame retardant adjuvant added to the natural rubber elastomer is preferably more than 150 parts by weight and 800 parts by weight per 100 parts by weight of the natural rubber elastomer. When the amount of the flame retardant is 150 parts by weight or less, the flame retardant level according to the UL510FR combustion test is difficult to be achieved, and when the amount of the flame retardant exceeds 800 parts by weight, the viscosities of both the natural rubber-based flame retardant composition layer and the vulcanized treated natural rubber-based flame-retardant pressure-sensitive adhesive layer rapidly increase. Increasingly, these formulations are not only difficult to apply, but even when applied, a problem arises in that the contact adhesion to the woven fabric is reduced, or the pressure-sensitive adhesive is susceptible to breakage of the interface.

The vulcanized natural rubber-based flame retardant pressure-sensitive adhesive layer may contain a tackifier resin. The amount of the tackifier resin is preferably 10 to 200 parts by weight per 100 parts by weight of the natural rubber elastomer, but is preferably 40 to 150 parts by weight. If the added amount of the tackifier resin is less than 10 parts by weight, the pressure-sensitive adhesive force and the adhesiveness are unbalanced to lose the adhesiveness, while if it exceeds 200 parts by weight, the viscosity as the pressure-sensitive adhesive is insufficient, satisfactory adhesiveness cannot be exhibited. .

The natural rubber flame retardant composition layer may contain a tackifier resin. The amount of the tackifier resin is preferably 10 to 200 parts by weight, and more preferably 40 to 150 parts by weight per 100 parts by weight of the natural rubber elastomer. When the amount of the tackifier resin added is less than 10 parts by weight, the adhesiveness of the layer applied and penetrated onto the woven substrate becomes too low, and the pressure-sensitive adhesive tape may not be able to be unsealed, whereas 200 parts by weight When it exceeds, a natural rubber type flameproof composition layer will become weak and it cannot maintain a sufficiently high coating film strength.

In a preferred embodiment of the present invention, the ratio of the tackifier resin to the natural rubber elastomer in the flame retardant composition layer is higher than the ratio of the tackifier resin to the natural rubber elastomer in the pressure-sensitive adhesive layer. When these ratios are reversed, the tackifier resin is moved from the pressure-sensitive adhesive layer toward the flameproof composition layer on the inner side thereof, whereby the pressure-sensitive adhesive coated on the outer side may decrease the pressure-sensitive adhesiveness over time. This depends on the composition of the pressure-sensitive adhesive layer. In the adhesive tape of the present invention having the above-described configuration, even if a large amount of inorganic flame retardant is compounded in the pressure-sensitive adhesive layer brought into contact with the adherend, deterioration in pressure-sensitive adhesiveness can be prevented.

The flame retardant composition layer may be composed of two or more layers. For example, by adjusting the flame retardant composition in contact with the woven substrate, it is possible to have a suitable composition for achieving both flame retardancy and adhesion to the fabric. By adjusting another flame retardant composition layer in contact with the pressure-sensitive adhesive layer, the adhesion may be less considered but may have an appropriate composition to achieve maximum flame retardancy.

As the metal hydroxide for use in the flame-proof pressure-sensitive adhesive tape of the present invention, aluminum hydroxide and magnesium hydroxide are preferable, and these may be used alone or in combination.

The flame retardant aid for use in the flame-retardant pressure-sensitive adhesive tape of the present invention preferably does not generate halogen gas upon incineration, is odorless, and there is no particular limitation, but the group consists of tin oxide, zinc meta-stannate, zinc hydroxystannate and zinc borate. At least one is selected from.

In the natural rubber flame retardant composition layer and the vulcanized natural rubber flame retardant pressure-sensitive adhesive layer, the coating film strength and the pressure-sensitive adhesiveness are adjusted by adding an inorganic filler, an ultraviolet absorber-containing antioxidant and an oil.

When applying or penetrating and adhering to a woven fabric substrate, the amount of the natural rubber-based flame retardant composition layer is preferably 3 to 250 g / m 2. If the amount of the layer is less than 3 g / m 2, the advantage of meeting the flame resistance level under the US510FR combustion test criteria is not easily achieved, and if it exceeds 250 g / m 2, there is a disadvantage that the flexibility of the substrate is lost.

It is preferable that it is 20-600 g / m <2>, and, as for the application quantity of the vulcanization-treated natural rubber type flameproof adhesive layer, it is more preferable that it is 20-250 g / m <2>. If the coating amount is less than 20 g / m 2, it is difficult to obtain pressure-sensitive adhesiveness to adhere to a complicated shape, whereas if it exceeds 600 g / m 2, the defects in appearance and cost increase as a pressure-sensitive adhesive tape such as exudation may occur. This is not practical.

The woven fabric substrate used for the flammable pressure-sensitive adhesive tape of the present invention is not particularly limited, and may be a woven fabric made of not only flammable woven fabrics such as cotton cloth but also flame retardant materials such as polyimido resin or glass. However, combustible woven fabrics are advantageous because they are excellent in flexibility and inexpensive.

Combustible woven fabrics which are preferably used for the flame-retardant pressure-sensitive adhesive tape of the present invention are single yarns such as staple fibers, cotton, polyester, polyethylene, polypropylene, and acrylic fibers having 38 to 300 deniers in both warp and weft yarns, or their fibers. It may be a short fiber or a textile woven from blended yarns. If the thickness is smaller than 38 denier, the woven fabric has the drawback of being too thick as a substrate of the pressure-sensitive adhesive tape and having a large amount of flexibility and resin, while exceeding 300 denier, the strength of the woven fabric is insufficient.

The density of the woven fabric is suitably 25 to 450 yarns / inch in both warp and weft yarns. If the density is lower than 25 yarns / inch, the strength of the substrate is insufficient, whereas if it exceeds 450 yarns / inch, the flame retardant composition is excessively adhered during the flame retardant treatment, so that the woven substrate becomes too high in woven cloth. The original touch is lost.

The flameproof adhesive tape to which the natural rubber type flameproof pressure-sensitive adhesive to which the board | substrate was vulcanized was apply | coated, for example can be manufactured as follows. The finely ground natural rubber and other synthetic rubbers are dissolved in a solvent such as toluene so as to have appropriate plasticity. An inorganic flame retardant such as a compound flame retardant composed of a metal hydroxide and a flame retardant, a tackifier resin, an inorganic filler, and an antioxidant are added and dispersed therein. Subsequently, aminoalkylalkoxysilane is added and stirred to prepare a natural rubber type flameproof composition. This composition is applied to a flammable woven fabric as described above by a reversible applicator or the like in a predetermined amount to prepare a woven fabric substrate which is flameproofed. On the substrate surface, a natural rubber-based flameproof pressure-sensitive adhesive solution prepared in the same manner as the natural rubber-based flame retardant composition is applied and dried by a roll applicator, thereby completing the vulcanization reaction. Next, the pressure-sensitive adhesive tape of the present invention can be obtained by only winding this.

The flame-retardant pressure-sensitive adhesive tape of the present invention is particularly useful for fixing a component that is generated by a large current, such as a television component where flame resistance is important because a large current passes and the temperature may rise.

The present invention provides a pressure-sensitive adhesive composition composed of a vulcanized natural rubber-based flame-retardant pressure-sensitive adhesive layer obtained by vulcanizing a woven substrate and a natural rubber elastomer with an aminoalkylalkoxysilane and mixing inorganic flame retardants such as the metal hydroxide flame retardant and tackifier resin described above. Provide a tape. It is preferable to infiltrate the woven substrate with a natural rubber flame retardant composition in which a metal hydroxide flame retardant and an aminoalkylalkoxysilane are blended. The pressure-sensitive adhesive tape of the present invention uses a metal hydroxide flame retardant and an aminoalkylalkoxysilane. They are safe for the human body and have no adverse effects on the environment, so they can be vulcanized using low energy, have no oxygen inhibitory action, do not corrode the adherent metals or discolor paper, woven fabrics or plastics and are odorless. In addition, the pressure-sensitive adhesive tape of the present invention has the advantage that does not emit halogen gas, sulfurous acid gas or nitrogen oxide which adversely affects the environment during incineration.

Example

Hereinafter, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to these Examples. In the examples, "parts" are parts by weight and "%" is parts by weight.

(1) Preparation of Natural Rubber Flame Retardant Composition Solution:

Examples of the rubber-based composition to be applied and penetrated into the flammable woven fabric include 65 parts of natural rubber having a plasticity adjusted to 76 and 100 parts of rubber elastomer composed of 35 parts of SBR, 350 parts of magnesium hydroxide (FINEMAG SN-T, manufactured by Air Water), zinc stannate (FLAMTARD H, product of Nippon Light Metal Co., Ltd.) 50 parts, aminoalkylalkoxysilane 5 parts, tackifier resin ESCOREZ 1304, product of Exxon Chemicals) 120 parts, antioxidant (NS-6, Ouchi Shinko Chemical Industrial product ) 1 part was dissolved in 1,200 parts of toluene to prepare a 34% solution of the natural rubber flame retardant composition.

(2) Preparation of rubber flame retardant pressure sensitive adhesive solution:

Examples of the rubber-based flame-retardant pressure-sensitive adhesive include 100 parts of rubber elastomer composed of 70 parts of natural rubber whose plasticity is adjusted to 35 and 30 parts of SBR, 150 parts of magnesium hydroxide, 50 parts of zinc stannate, 1 part of aminoalkylalkoxysilane, and a tackifier resin ( 70 parts of ESCOREZ 1304, manufactured by Exxon Chemicals), 10 parts of titanium oxide, and 1 part of antioxidant (NS-6) were dissolved in 382 parts of toluene to prepare a 50% solution of a rubber-based flame-retardant pressure-sensitive adhesive.

Example 1

Method for producing a pressure-sensitive adhesive tape of which the substrate is a vulcanized natural rubber-based flame retardant fabric:

The rubber system prepared in the above step (1) has a warp yarn having a density of 180 yarns / inch and 75 deniers and a weft yarn of 53 yarns / inch and 150 deniers on the surface and inside of a tape substrate made of refined combustible acetate woven fabric. The flame retardant composition solution was applied and infiltrated by a reversible kiss applicator so that the coating amount after drying was 15.5 g / m 2, and then dried at 80 ° C. for 1 minute, and then the tape was wound up.

The flame retardant composition was prepared using the pressure-sensitive adhesive prepared in the step (2). In the formulation thereof, magnesium hydroxide was increased to 400 parts by 150 parts, zinc stannate was increased to 175 parts by weight, and aminoalkylalkoxysilane was 1 The part was increased to 7 parts, and the tackifier resin (ESCOREZ 1304) was increased to 70 parts to 120 parts. The 50% toluene solution of the flame retardant composition solution was applied to the surface of the flame-retardant acetate woven tape substrate prepared above, followed by drying so that the coating amount after drying was 150 g / m 2.

Subsequently, the 50% flameproof pressure-sensitive adhesive solution prepared in the step (2) was applied so that the coating amount after drying was 50 g / m 2 and then dried to obtain a pressure-sensitive adhesive tape in which the substrate was made of a rubber-based flameproof woven fabric to which the substrate was vulcanized.

After cutting the roll to 12 mm in width, the thickness, tensile strength, elongation, peel adhesion, peel adhesion after heating, sea power, Adhesion, holding force, electrical corrosion coefficient and dielectric breakdown voltage were measured, and a combustion test and an odor test were also performed. The evaluation results satisfied all items of pressure-sensitive adhesiveness, electrical properties, flame retardancy and odor.

The results are shown in Table 1. As can be seen from these results, the peel adhesion and the adhesiveness are particularly excellent.

Example 2

Method for producing a pressure-sensitive adhesive tape of which the substrate is a vulcanized natural rubber-based flame retardant fabric:

The same solution as used in Example 1, but on the surface and inside of the tape substrate made of non-refinable combustible acetate fabric, the solution prepared in the step (1) is applied so that the coating amount after drying is 18.5 g / ㎡ Infiltrated and then dried to prepare a flameproof acetate woven tape substrate.

Subsequently, the flame-retardant composition was prepared using the rubber-based flame-retardant pressure-sensitive adhesive prepared in the step (2), the magnesium hydroxide was changed to 400 parts, the zinc stannate was changed to 200 parts, and the aminoylcockxysilane was changed to 7 The tackifier resin (ESCOREZ 1304) was changed to 120 parts. A 50% toluene solution of the flame retardant composition was applied to the surface of the flame-retardant acetate woven tape substrate prepared above so that the coating amount after drying was 150 g / m 2.

Immediately, the 50% rubber-based flame retardant pressure-sensitive adhesive solution prepared in the step (2) was applied so that the coating amount after drying was 50 g / m 2 and then dried to vulcanize the rubber-based flame retardant woven substrate, further flame retardant composition layer, and flame-retardant pressure-reduced. A pressure-sensitive adhesive tape composed of an adhesive layer was obtained.

This tape roll was cut to 12 mm in width, and the same items as in Example 1 were evaluated. The results are shown in Table 1. As can be seen from these results, even in the case of using an unrefined acetate woven fabric, the electrocorrosion coefficient and the like also obtained good results.

Example 3

On the surface and inside of the same non-refinable combustible acetate woven tape substrate as used in Example 2, the solution prepared in the step (1) was applied and infiltrated so that the coating amount after drying was 15.5 g / m 2, and then dried to flameproof treatment. Acetate woven tape substrate was prepared.

Subsequently, the flame retardant composition was prepared using the rubber-based flame-retardant pressure-sensitive adhesive prepared in the step (2), when mixing magnesium hydroxide to 400 parts, zinc stannate to 200 parts, and aminoalkoxysilane to 7 parts. The tackifier resin (ESCOREZ 1304) was changed to 120 parts. A 50% toluene solution of the flame retardant composition was applied to the surface of the flame retardant acetate woven tape substrate so that the coating amount after drying was 150 g / m 2.

Immediately, the 50% rubber-based flame retardant pressure-sensitive adhesive solution prepared in the step (2) was applied so that the coating amount after drying was 50 g / m 2, followed by drying, followed by drying of the vulcanized rubber-based flame retardant woven substrate, additional flame retardant composition layer, and flame-retardant reduced pressure. A pressure-sensitive adhesive tape composed of an adhesive layer was obtained.

This tape roll was cut to 12 mm in width, and the same items as in Example 1 were evaluated. The results are shown in Table 1. As can be seen from these results, even in the case of using an unrefined acetate woven fabric, a good electrocorrosion coefficient was obtained.

Comparative Example 1

The rubber-based flame-retardant pressure-sensitive adhesive solution prepared in the step (2) was applied directly to a tape substrate surface composed of the same acetate woven fabric as used in Example 1 so that the coating amount after drying was 200 g / m 2, followed by 80 It dried at 2 degreeC for 2 minutes, and obtained the 30 m-roll product. This roll was cut to 12 mm in width, and the same items as in Example 1 were evaluated. The results are shown in Table 1. As can be seen from these results, the UL510FR combustion test evaluation failed. This is presumably due to the fact that flammable woven fabrics were exposed.

Comparative Example 2

The coating amount after drying the rubber-based flame retardant composition obtained by excluding 5 parts of an aminoalkylalkoxysilane from the formulation of the rubber-based composition prepared in the step (1) on the surface and inside of the tape substrate composed of the flammable acetate woven fabric of Example 1 was 15.5 g / m 2. The tape substrate was wound up by coating and infiltration to dryness and drying.

On the surface of the flameproof acetate woven tape substrate, the coating amount after drying the rubber-based flame-retardant pressure-sensitive adhesive solution obtained by excluding 1 part of aminoalkylalkoxysilane from the blend of the rubber-based flame-retardant pressure-sensitive adhesive prepared in the step (2) was 200 g / m 2. It was applied with a roll applicator and then dried at 80 ° C. for 2 minutes to obtain a 30 m-roll product.

This roll was cut to 12 mm in width, and the same items as in Example 1 were evaluated. The results are shown in Table 1. As can be seen from these results, the holding power was weak. This shows the vulcanization treatment effect by aminoalkylalkoxysilane.

Comparative Example 3

On the surface of the tape substrate made of the same acetate woven fabric as in Example 1, a flame retardant layer containing chloroprene rubber / antimony trioxide was applied by a gravure applicator so that the coating amount after drying was 92 g / m 2 and then dried.

Immediately thereafter, the pressure-sensitive adhesive composition composed of a phenol resin vulcanized natural rubber, a tackifier resin, and calcium carbonate was applied and dried by a roll applicator so that the coating amount after drying was 58 g / m 2, and then the tape was wound up. .

This tape was evaluated for the same items as in Example 1. The results are shown in Table 1. As can be seen from these results, in spite of the excellent flame retardancy, the smell was very unpleasant. This indicates that using a halogen flame retardant is disadvantageous.

 Item  Example  Comparative Example  One  2  3  One  2  3 Tape Strength (g / ㎡) ¹⁾  22.9  23.5  22.4  21.8  22.5  22.5   Penetration to Woven Substrate (g / ㎡)  15.5  18.5  15.5  0  15.5  0   Application amount of pressure-sensitive adhesive (g / ㎡)  200  200  200  200  200  147   Thickness (mm)  0.23  0.24  0.25  0.22  0.24  0.26 Tensile strength (Kg / 12mm) ²⁾  7.9  8.3  8.1  7.4  7.9  7.9 Elongation (N / 12 mm) ³⁾  25.1  23.8  24.3  26.3  24.5  24.2 Peel Adhesion (N / 12 mm) ⁴⁾  6.0  6.1  5.2  5.8  7.4  3.1 Peel Adhesion after Heating (N / 12 mm) ⁵⁾  13.8  16.1  12.1  13.2  10.2  8.8 Sea power (N / 12 mm) ⁶⁾  2.4  2.4  2.8  3.4  3.6  6.8 Adhesiveness ⁷⁾  8  8  11  7  7  15 Holding force (slip: mm) ⁸⁾  0.3  0.1  0.3  0.7  Drop in 3 seconds  1.3 Electrical corrosion coefficient ⁹⁾  1.0  0.92  0.98  0.43  0.90  0.85 Dielectric breakdown voltage (KV) ¹⁰⁾  3..0  3.2  3.5  2.4  2.1  2.0 UL510FR combustion test (longest time) judgment ¹¹⁾  34 seconds passed  43 seconds passed   27 sec passr  1 minute 5 seconds failed  52 seconds passed  10 seconds passed Smell ¹²⁾  170  170  170  165  179  750 Oxygen index ¹³⁾  22.8  23.2  24.2  21.8  24.0  28.2

Test Methods

1) ^Strength:. 10 g measured with a strength tester (36 mm (width) and 15 ^(angle) and)

2) Tensile Strength: JIS C-2107-1999

3) Elongation: JIS C-2107-1999

4) Peel Adhesion: JIS C-2107-1999

5) Peel Adhesion after Heating: JIS C-2107-1999 (120 ° C × 2H)

6) Navy power: JIS Z-0237-2000

7) adhesive: JIS Z-0237-2000 (angle: ^10).

8) Holding force: JIS C-2107-1999 (120 ° C × 30 minutes, 12 mm × 25 mm, 100 g)

9) Electrical Corrosion Coefficient: JIS C-2107-1999

10) Insulation breakdown voltage: JIS C-2107-1999

11) UL510FR Combustion Test: During 5 repeated ignition tests, each time passed less than 60 seconds of fire extinguishing time.

12) Odor: measured using an odor sensor (generally, manufactured by Shin Cosmos Denki)

13) Oxygen Index: JIS K-7201-1972

As described above, the flame-retardant pressure-sensitive adhesive tape having a woven substrate using a natural rubber vulcanized with an aminoalkylalkoxysilane and a metal hydroxide flame retardant according to the constitution of the present invention is not only electrically insulating and flexible, but also a metal adhesive Or it does not yellow the adherends such as woven fabrics and paper, there is an advantage that does not emit halogen gas or sulfurous acid gas when incinerated.

Example 4

Method for producing a pressure-sensitive adhesive tape of which the substrate is a vulcanized natural rubber fireproof woven fabric

The rubber-based flame retardant composition solution prepared in step (1) above and on the surface and inside of a tape substrate composed of refined flammable acetate woven fabric having a warp density of 180 yarns / inch and 75 deniers and a weft yarn of 53 yarns / inch and 150 deniers. Was applied and infiltrated using a reversible kiss applicator so that the coating amount after drying was 15.5 g / m 2, and then dried at 80 ° C. for 1 minute, and the tape was wound up.

The rubber-based flame-retardant pressure-sensitive adhesive solution prepared in the step (2) was applied to the tape surface of the flame-resistant acetate woven fabric using a roll applicator so that the coating amount after drying was 200 g / m 2, and then dried at 80 ° C. for 2 minutes. To obtain a 30 m-roll product. After cutting this roll to width 12mm, thickness, tensile strength, elongation, peeling adhesive force, peeling adhesive force after heating, sea power, adhesiveness, retention force, an electrical corrosion coefficient, and dielectric breakdown voltage were measured, and also a combustion test and an odor test were carried out. It was done. The evaluation results satisfied all items of pressure-sensitive adhesiveness, electrical properties, flame retardancy and odor.

Example 5

Method for producing a pressure-sensitive adhesive tape, the substrate is a vulcanized natural rubber-based flame retardant fabric:

On the surface and inside of the tape substrate composed of the same non-combustible combustible acetate fabric as used in Example 4, the solution prepared in the step (1) was applied and infiltrated so that the coating amount after drying was 18.5 g / m 2, and then dried. A tape substrate composed of a flame resistant acetate woven fabric was prepared. Subsequently, the rubber-based flame retardant pressure-sensitive adhesive solution prepared in step (2) was applied by a roll applicator so that the coating amount after drying was 200 g / m 2, and then dried at 80 ° C. for 2 minutes to obtain a 30 m-roll product. This roll was cut to 12 mm in width, and the same items as in Example 1 were evaluated. Also in the case of using an unrefined acetate woven fabric, the electrocorrosion coefficient and the like also obtained good results.

The flame-retardant pressure-sensitive adhesive tape according to the present invention can be vulcanized at low energy, has no oxygen inhibiting action, is odorless and does not corrode metals or discolor the adherends such as paper, fabric or plastic. In addition, the present invention can be used for electric and electronic parts and electrical equipment parts without incinerated gases harmful to the environment such as halogen gas or sulfurous acid gas when incineration of waste tape and insoluble tape.

Claims (22)

A flame retardant pressure-sensitive adhesive layer comprising a woven fabric substrate and a flame-retardant pressure-sensitive adhesive layer on at least one main surface of the woven substrate, wherein the flame-retardant pressure-sensitive adhesive layer comprises a natural rubber elastomer containing 50% by weight or more of natural rubber components, and 0.1 to 10 weight parts per 100 parts by weight of the natural rubber elastomer. It is composed of an aminoalkyl alkoxysilane which is a negative vulcanizing agent, a tackifier resin of 10 to 200 parts by weight per 100 parts by weight of the natural rubber elastomer, and an inorganic flame retardant of more than 150 parts by weight to 800 parts by weight per 100 parts by weight of the natural rubber elastomer. The inorganic flame retardant is composed of a metal hydroxide and an inorganic flame retardant selected from the group consisting of tin oxide, zinc metatartrate, zinc hydroxytin and zinc borate, and the natural rubber elastomer is vulcanized with aminoalkylalkoxysilane, UL510FR Established continuous combustion time Flame-retardant pressure-sensitive adhesive tape, characterized in that less than 60 seconds. A flameproof pressure-sensitive adhesive layer and a flameproof composition layer on the side of the substrate of the flameproof pressure-sensitive adhesive layer on at least one main surface of the woven substrate, wherein the flameproof pressure-sensitive adhesive layer and the flameproof composition layer each contain at least 50% by weight of a natural rubber component. Natural rubber-based elastomers to be contained, aminoalkylalkoxysilane which is 0.1 to 10 parts by weight of a vulcanizing agent per 100 parts by weight of the natural rubber elastomer, a tackifier resin that is 10 to 200 parts by weight per 100 parts by weight of the natural rubber elastomer, and It is composed of an inorganic flame retardant of more than 150 parts by weight and 800 parts by weight per 100 parts by weight of the natural rubber elastomer, which is an inorganic flame retardant selected from the group consisting of metal hydroxides, tin oxide, zinc meta-stannate, zinc hydroxytin and zinc borate. Made of, the natural rubber-based Ella The tomer is vulcanized with aminoalkylalkoxysilane, the flame retardant content in the flame retardant composition layer is higher than the flame retardant content in the flame retardant pressure-sensitive adhesive layer, and the flame retardant pressure-sensitive adhesive is characterized in that the continuous combustion time established by UL510FR is less than 60 seconds. tape. The flameproof pressure-sensitive adhesive tape according to claim 1 or 2, wherein the woven substrate is infiltrated by the flameproof pressure-sensitive adhesive layer or the flame retardant composition layer, whereby the substrate is embedded in the infiltrating flameproof pressure-sensitive adhesive layer or the flame retardant composition layer. . The flameproof pressure-sensitive adhesive tape according to claim 1 or 2, wherein the woven substrate has a second surface opposite to the flameproof pressure-sensitive adhesive layer, and another layer of flameproof composition is applied to the second surface. delete The flame retardant composition layer according to claim 1 or 2, wherein the flame retardant composition layer further contains a tackifier resin, and the weight ratio of the tackifier resin to the natural rubber elastomer in the flame retardant composition layer is higher than the weight ratio in the flame retardant pressure-sensitive adhesive layer. Flame-proof pressure-sensitive adhesive tape. The flame-retardant pressure-sensitive adhesive tape according to claim 1 or 2, wherein the substrate is a flammable woven fabric. delete delete The flame-retardant pressure-sensitive adhesive tape of claim 2, wherein the blending ratio of the tackifier resin contained in the flame retardant composition layer to the elastomer is higher than the blending ratio of the tackifier resin contained in the flame-retardant pressure-sensitive adhesive layer. The flame retardant composition layer according to claim 2, wherein the flame retardant composition layer is composed of two or more layers of flame retardant composition layers, and a blending ratio of the tackifier resin to the elastomer contained in the flame retardant composition layer in contact with the flame retardant pressure-sensitive adhesive layer is contained in the flame retardant pressure-sensitive adhesive layer. A flame-retardant pressure-sensitive adhesive tape having a higher ratio than the compounding ratio of the tackifier resin to the elastomer. The flame-retardant pressure-sensitive adhesive tape according to claim 1 or 2, wherein the inorganic flame retardant contains at least one of aluminum hydroxide and magnesium hydroxide. delete The aminoalkylalkoxysilane according to claim 1 or 2, wherein the aminoalkylalkoxysilane is N-β (aminoethyl) γ -aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ -aminopropylmethyldiethoxysilane, N-β (Aminoethyl) γ -aminopropyltrimethoxysilane, N-β (aminoethyl) γ -aminopropyltriethoxysilane, γ -aminopropyltrimethoxysilane and γ -aminopropyltriethoxysilane Flame-proof pressure-sensitive adhesive tape that is selected. The flame retardant according to claim 1 or 2, wherein one or both of the flame retardant pressure-sensitive adhesive layer and the flame retardant composition layer further contain at least one component selected from the group consisting of inorganic fillers, ultraviolet absorbers, antioxidants and oils. Pressure-sensitive adhesive tape. The flame-retardant pressure-sensitive adhesive tape according to claim 1 or 2, wherein the coating amount of the flame-retardant composition layer is 3 to 250 g / m 2. The flame-proof pressure-sensitive adhesive tape according to claim 1 or 2, wherein the coating amount of the flame-proof pressure-sensitive adhesive layer is 20 to 600 g / m 2. The flammable woven fabric according to claim 1 or 2, wherein the combustible woven fabric is a short fiber or cross woven fabric from single yarn or blended yarn containing fibers selected from the group consisting of staple fibers, cotton, polyester, polyethylene, polypropylene and acrylic fibers, Flame-retardant pressure-sensitive adhesive tape of both warp and weft thickness of 38 to 300 denier, the fiber density of 25 to 450 yarn / inch. The flame retardant pressure-sensitive adhesive tape according to claim 1 or 2, wherein any one or both layers of the flame retardant pressure-sensitive adhesive layer and the flame retardant composition layer do not contain sulfur and halogen. delete delete The flame-retardant pressure-sensitive adhesive tape according to claim 1 or 2, which is used for a television component or a deflection coil.

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