JP2025002106A - Butyl-based rubber adhesive composition, adhesive tape, waterproof sheet for roofing, adhesive composition for fixing toilets, and joint body - Google Patents

Abstract

To provide a butyl-based rubber adhesive composition with excellent adhesion, tackiness, and holding power (shear force).SOLUTION: The present invention provides a butyl-based rubber adhesive composition, containing 100 pts.mass of a butyl-based rubber, 150-700 pts.mass of an inorganic compound, 20-300 pts.mass of a softener, and 5-70 pts.mass of a fibrous organic compound.SELECTED DRAWING: None

Description

The present invention relates to a butyl-based rubber adhesive composition. More specifically, the present invention relates to a butyl-based rubber adhesive composition used to bond roof tiles to waterproof sheets, a toilet fixing adhesive composition used to bond a toilet to a floor, and the like. The present invention also relates to an adhesive tape using the butyl-based rubber adhesive composition, a roof waterproof sheet using the butyl rubber adhesive composition, an assembly formed by bonding a roof tile to a waterproof sheet with the butyl rubber adhesive composition, and an assembly formed by bonding a toilet to a floor.

Generally, on the roofs of buildings such as houses, a waterproof sheet made of synthetic rubber or the like is laid between the roofing base and the roofing tiles to prevent the infiltration of rainwater, etc. This waterproof sheet is joined to the roofing tiles using mechanical fastening methods such as nails, bolts, and rivets, joining methods using solvent-based adhesives, or joining methods using acrylic rubber or butyl rubber adhesive tape.

Among these, the most widely used joining method is one that uses rubber-based adhesive tape, due to its water resistance and ease of use. Patent Document 1 proposes a method of joining roof tiles and waterproof sheets using butyl rubber-based adhesive tape. However, when the entire roof is exposed to high temperatures due to strong summer sunlight, the shear strength of the adhesive decreases, causing creep deformation.

In order to improve the shear strength of the adhesive, methods have been proposed in which the adhesive is impregnated into the nonwoven fabric (Patent Documents 2 and 3) and fibers are dispersed in the adhesive (Patent Document 4).

JP2004-300674 JP 10-245534 A JP2005-062341 JP 08-325532

In general, adhesive strength, tack, and holding strength (shear strength) are called the three elements of adhesion, and among these, tack and holding strength (shear strength) are trade-off elements. In the method of impregnating a nonwoven fabric with an adhesive as in Patent Documents 2 and 3, the constraint of the nonwoven fabric suppresses the deformation of the adhesive, improving the shear strength, but there is a problem that the instantaneous adhesion to the adherend, called tack, decreases.
In addition, the adhesive of Patent Document 4 has good tack because there is no constraint like in nonwoven fabric, but since it is composed only of butyl rubber and fibers, there is an issue with shear force.
As described above, none of the methods achieved a balance between the three adhesive elements of adhesive strength, tack, and holding strength (shear strength).

The object of the present invention is to provide a butyl-based rubber adhesive composition that has excellent adhesion, tack, and retention (shear strength). The butyl-based rubber adhesive composition can be suitably used, for example, for waterproof sheets for roofs and for fastening toilets and floors that have previously been joined by mechanical fastening methods such as nails, bolts, and rivets.

The inventors conducted extensive research to solve the above problems. As a result, they discovered that the above problems could be solved by using a composition with a specific blend, which led to the completion of the present invention.

That is, according to the present invention, the following inventions are provided.
[1] A butyl-based rubber pressure-sensitive adhesive composition comprising: 100 parts by mass of a butyl-based rubber; 150 to 700 parts by mass of an inorganic compound; 20 to 300 parts by mass of a softener; and 5 to 70 parts by mass of a fibrous organic compound.
[2] The butyl-rubber pressure-sensitive adhesive composition according to [1], wherein the inorganic compound contains 30 mass % or more of a clay mineral.
[3] The butyl-based rubber pressure-sensitive adhesive composition according to [1] or [2], wherein the average fiber length of the fibrous organic compound is 0.5 to 10 mm.
[4] A pressure-sensitive adhesive tape comprising the butyl-based rubber pressure-sensitive adhesive composition according to any one of [1] to [3].
[5] A waterproof sheet for roofs, comprising: an adhesive layer containing the butyl-based rubber adhesive composition according to any one of [1] to [3]; and a waterproof sheet laminated on the adhesive layer.
[6] A joint comprising a roof tile and a waterproof sheet joined together with the butyl rubber pressure-sensitive adhesive composition according to any one of [1] to [3].
[7] A pressure-sensitive adhesive composition for fixing a toilet, which is used for fixing a toilet to a floor, comprising the butyl-based rubber pressure-sensitive adhesive composition according to any one of [1] to [3].
[8] A joint formed by joining a toilet bowl and a floor with the adhesive tape described in [4].
[9] A joint formed by joining a toilet and a floor with the pressure-sensitive adhesive composition for fixing a toilet according to [7].

1A and 1B are diagrams illustrating a method for evaluating creep resistance, in which Fig. 1A shows a state at the start of the test, and Fig. 1B is a diagram illustrating the amount of displacement after being left standing.

The following describes a preferred embodiment of the present invention. Note that the embodiment described below is an example of a typical embodiment of the present invention, and is not intended to narrow the scope of the present invention.

[Butyl-based rubber pressure-sensitive adhesive composition]
The butyl-rubber adhesive composition of the present invention contains a butyl-rubber, an inorganic compound, a softener, and a fibrous organic compound. More specifically, the butyl-rubber adhesive composition contains 100 parts by mass of butyl-rubber, 150 to 700 parts by mass of the inorganic compound, 20 to 300 parts by mass of the softener, and 5 to 70 parts by mass of the fibrous organic compound. Each component will be described below.

<Butyl rubber>
The butyl-based rubber pressure-sensitive adhesive composition according to the present invention has the effect of little change in adhesive strength over time and good water resistance by containing a butyl-based rubber. In the present invention, the butyl-based rubber means a rubber containing a butyl-based polymer containing a monomer unit derived from isobutylene. That is, the butyl-based rubber contains an isobutylene monomer unit. Moreover, the butyl-based rubber according to one embodiment of the present invention can contain an isobutylene monomer unit and an isoprene monomer unit, that is, it can contain a copolymer obtained by copolymerizing raw material monomers containing isobutylene and isoprene. The butyl-based rubber may be, for example, butyl rubber, partially crosslinked butyl rubber, recycled butyl rubber, polyisobutylene, chlorinated butyl rubber, or brominated butyl rubber, and the butyl-based rubber pressure-sensitive adhesive composition can contain one or more butyl-based rubbers selected from these. Moreover, the butyl-based rubber pressure-sensitive adhesive composition according to the present invention has good conformability to the adherend by containing a butyl-based rubber, and is therefore suitable for use in joining adherends of different shapes, such as a roof tile and a waterproof sheet, or a flooring material and a toilet.

The butyl-based rubber adhesive composition according to the present invention may contain a rubber component other than butyl-based rubber. Examples of rubber components other than butyl-based rubber include liquid rubbers such as liquid polyisoprene, liquid polybutadiene, liquid polychloroprene, and liquid polybutene, natural rubber, isoprene rubber, butadiene rubber, 1,2-polybutadiene rubber, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, butyl rubber, chlorinated butyl rubber, chlorinated polyethylene rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber (EPDM), ethylene-vinyl acetate rubber, chloroprene rubber, chlorosulfonated polyethylene, acrylic rubber, epichlorohydrin rubber, silicone rubber, fluororubber, urethane rubber, and styrene-based thermoplastic elastomer. These rubber components other than butyl-based rubber may be used in combination of one or more types. The proportion of butyl-based rubber to the total rubber components is preferably 50% by mass or more, and more preferably 80% by mass or more. The ratio of butyl-based rubber to the total rubber component is, for example, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100% by mass, and may be within a range between any two of the numerical values exemplified here.

<Inorganic Compounds>
Examples of inorganic compounds include metal oxides such as alumina, aluminosilicate, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, and ferrites; hydrated inorganic substances such as aluminum hydroxide, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, and hydrotalcite; metal carbonates such as basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, strontium carbonate, and barium carbonate; calcium salts such as calcium sulfate and calcium silicate, glass beads, silica-based balloons, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon balloons, charcoal powder, various metal powders, and potassium titanate. , magnesium sulfate, lead zirconate titanate, aluminum borate, molybdenum sulfide, silicon carbide, zinc borate, various magnetic powders, fly ash, inorganic hollow fillers, perlite, obsidian, perlite, rosin, diatomaceous earth, dehydrated sludge, boron, sodium tetraborate hydrate (borax), inorganic phosphorus compounds, silica, glass fibers (E glass fibers, C glass fibers, S glass fibers, D glass fibers), rock wool, ceramic fibers (silica alumina fibers, alumina fibers, silica fibers), zirconia fibers, carbon fibers, bulk alkaline earth silicate fibers, gypsum fibers, carbon fibers, metal fibers, slag fibers, basalt fibers, and other fibrous inorganic compounds, clay mineral-based inorganic compounds containing clay minerals, and the like. These inorganic compounds may be used alone or in combination of two or more.

As the clay mineral-based inorganic compound, at least one selected from natural or synthetic inorganic clay minerals is used. Examples of clay minerals include smectite clays such as bentonite, montmorillonite, and hectorite, fibrous clays such as sepiolite and palygorskite, sericite, illite, glauconite, chlorite, talc, zeolite, beidellite, nontronite, saponite, hectorite, sauconite, stevensite, cristopalite, smectite, kaolin, and clay (hydrated aluminum silicate). These clay minerals may be used alone or in combination of two or more.

The inorganic compound preferably contains 30% or more by mass of clay minerals. The proportion of clay minerals in the inorganic compound may be, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100% by mass, and may be within a range between any two of the values exemplified here.

The content of the inorganic compound is 150 to 700 parts by mass, preferably 230 to 595 parts by mass, and more preferably 300 to 470 parts by mass, per 100 parts by mass of butyl-based rubber. If it is less than 150 parts by mass, it will be too soft and the creep resistance will be poor. If it exceeds 700 parts by mass, it will be too hard and the tack (stickiness) will be poor. Specifically, the content of the inorganic compound is, for example, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700 parts by mass, and may be within a range between any two of the numerical values exemplified here.

<Softener>
The type of softener is not particularly limited as long as it does not impair the object of the present invention, and one or more of any known softeners can be freely selected and used. Examples of softeners include paraffinic, naphthenic, and aromatic process oils, rapeseed oil, phthalates, adipic esters, alkylsulfonic esters, sebacic esters, process oils, and mineral oils. These softeners may be used alone or in combination of two or more.

The content of the softener is 20 to 300 parts by mass, preferably 50 to 170 parts by mass, and more preferably 80 to 145 parts by mass, per 100 parts by mass of butyl-based rubber. If it is less than 50 parts by mass, it will be too hard and the tack (stickiness) will be poor. If it exceeds 300 parts by mass, it will be too soft and the creep resistance will be poor. The content of the softener is specifically, for example, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, or 300 parts by mass per 100 parts by mass of butyl-based rubber, and may be within a range between any two of the numerical values exemplified here.

<Fibrous organic compound>
The shape of the fibrous organic compound may be fibrous, and examples of the cross-sectional shape of the fiber include a circle, an ellipse, and a polygon. When the average fiber length of the fibrous organic compound is L and the average diameter is D, the L/D of the fiber is, for example, more than 10, preferably 50 or more, and more preferably 100 or more. The upper limit is not particularly specified, but is, for example, 10,000. The average diameter of the fibrous organic compound is, for example, 1 to 100 μm, preferably 2 to 50 μm, and more preferably 5 to 20 μm. The average fiber length of the fibrous organic compound is, for example, 0.1 to 15 mm, and preferably 0.5 to 10 mm. The average fiber length of the fibrous organic compound is, for example, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5, 13.0, 13.5, 14.0, 14.5, or 15.0 mm, and may be within a range between any two of the numerical values exemplified here.

Examples of fibrous organic compounds include meta-aramid fibers, para-aramid fibers, amide fibers, pulp fibers, cellulose fibers (pulp fibers), polyparaphenylene benzobisoxazole fibers, polyarylate fibers, etc. These fibrous organic compounds may be used alone or in combination of two or more types. It is preferable that the fibrous organic compounds are contained in a form in which the fibers are dispersed in the composition.

The average fiber length and average diameter of a fibrous organic compound are determined by measuring the length of a sufficiently large number of fibrous organic compounds, i.e., 20 or more, and averaging the lengths to obtain the average fiber length and average diameter.

The fiber length and diameter of fibrous organic compounds can be measured, for example, using a field emission scanning electron microscope (FE-SEM).

The content of the fibrous organic compound is 5 to 70 parts by mass, preferably 10 to 55 parts by mass, and more preferably 15 to 40 parts by mass, per 100 parts by mass of butyl-based rubber. If it is less than 5 parts by mass, it will be too soft and the creep resistance will be poor. If it exceeds 70 parts by mass, the adhesion will be poor. Specifically, the content of the fibrous organic compound is, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, or 70 parts by mass per 100 parts by mass of butyl-based rubber, and may be within a range between any two of the numerical values exemplified here.

The butyl-based rubber adhesive composition of the present invention may contain additives such as tackifiers, vulcanizing agents, antioxidants, vulcanization accelerators, and lubricants that are used in ordinary rubber compositions, provided that the purpose of the present invention is not impaired. When a vulcanizing agent or vulcanization accelerator is added, the total amount is preferably 0.05 parts by mass or less, or 0.01 parts by mass or less.

The butyl-based rubber adhesive composition can be obtained by kneading butyl-based rubber, an inorganic compound, a softener, a fibrous organic compound, and other necessary additives using a kneading device (e.g., a kneader mixer, etc.).

[Adhesive tape]
The butyl-based rubber pressure-sensitive adhesive composition according to the present invention can be suitably used for a pressure-sensitive adhesive tape for tile roofs. For example, the components to be contained in the butyl-based rubber pressure-sensitive adhesive composition can be kneaded using a kneading device or the like, and the kneaded product can be formed into a tape-like pressure-sensitive adhesive tape for tile roofs having adhesiveness on both sides. In this case, the pressure-sensitive adhesive tape does not need to have a substrate.

The kneading device used when kneading the components is not particularly limited, and any known kneading device can be freely selected to perform the kneading. Examples of kneading devices include a Banbury mixer, a kneader mixer, and a two-roll mill. The method for forming the kneaded material into a tape is also not particularly limited, and any known forming method can be freely selected and used. Examples of such methods include molding methods such as roll molding and extrusion molding.

The adhesive tape obtained as described above has excellent adhesion and creep resistance because it uses the butyl-based rubber adhesive composition of the present invention. As a result, the durability of the joint formed by joining roof tiles and a waterproof sheet using this adhesive tape can also be improved.

[Tapering sheet for roofs]
The waterproof sheet for roofs according to the present invention comprises an adhesive layer and a waterproof sheet. Each of the components will be described below.

<Adhesive Layer>
The pressure-sensitive adhesive layer is made of the above-mentioned butyl-based rubber pressure-sensitive adhesive composition. Details of the butyl-based rubber pressure-sensitive adhesive composition will not be described. The above-mentioned pressure-sensitive adhesive tape can also be used as the pressure-sensitive adhesive layer.

<Waterproof sheet>
In the waterproof sheet for roofs according to the present invention, the waterproof sheet is laminated on the adhesive layer. The material used for the waterproof sheet is not particularly limited as long as it does not impair the object of the present invention, and one or more known materials may be freely selected and used. Examples of such materials include ethylene-propylene-diene rubber (EPDM) and polyvinyl chloride (PVC). Among these materials, EPDM is particularly preferred. This is because the waterproof sheet using EPDM has good adhesion to the butyl-based rubber adhesive composition.

＜Toilets＞
The above-mentioned butyl-based rubber adhesive composition can also be used, for example, for fixing a toilet to a floor. According to one embodiment of the present invention, a joint is provided in which a toilet is joined to a floor by the above-mentioned butyl-based rubber adhesive composition (adhesive composition for fixing a toilet) or an adhesive tape containing the butyl-based rubber adhesive composition. The joint constitutes a part of a toilet, and a toilet can be provided that includes a joint in which the toilet is fixed (joined) to the floor. The toilet and floor may be joined only by the above-mentioned butyl-based rubber adhesive composition, or may be joined by a mechanical fastening method such as a nail, a bolt, or a rivet.

The present invention will be described in more detail below with reference to examples. Note that the examples described below are representative examples of the present invention, and should not be construed as narrowing the scope of the present invention.

In the examples, the "parts" are based on mass. Details of the materials used in the examples are shown below.
(1) Butyl rubber: Butyl rubber ("Butyl 268" manufactured by JSR Corporation)
(2) Inorganic compounds Calcium carbonate: "TA044" manufactured by Chichibu Lime Industry Co., Ltd.
・Clay (containing aluminum silicate): "FA-80" manufactured by Gunma Feldspar Limited Partnership
(3) Softener Process oil: "AH-16" manufactured by Idemitsu Kosan Co., Ltd.
(4) Fibrous compounds <fibrous organic compounds>
Pulp fiber, average fiber length 1.2 mm: "Neofiber NS-10" manufactured by Oji Seibaku Co., Ltd.
Aramid fiber, 0.25, 0.5, 3, 10, 12 mm: "Twaron Short Cut Fiber" manufactured by Teijin Limited
<Fibrous inorganic compound>
Glass fiber, average fiber length 3 mm: "ECS03-350" manufactured by Central Glass Co., Ltd.

[Preparation of Butyl Rubber Pressure-Sensitive Adhesive Composition]
For each Example and Comparative Example, the components were mixed in the amounts shown in the table at 110° C. for 1 hour using a 3-liter kneader mixer to obtain a kneaded product that was a butyl-based rubber pressure-sensitive adhesive composition. The resulting kneaded product was then processed into a tape shape with a width of 25 mm and a thickness of 1 mm using an extruder with a die temperature set at 70° C. to produce a pressure-sensitive adhesive tape.

[evaluation]
The adhesive properties were evaluated according to the following method, and the results are shown in Tables 1 and 2.
<Adhesiveness (adhesive strength)>
A test piece was obtained by attaching an adhesive tape (one side of which was backed with a PET film (100 μm thick)) processed into a shape of 15 mm wide x 100 mm long x 1 mm thick to a ceramic tile processed into a shape of 30 mm wide x 125 mm long. This test piece was pressed back and forth once with a 2 kg rubber roller, and after leaving it for 20 minutes, the adhesive tape was peeled off in a 180° direction at a speed of 300 mm/min, and the adhesive strength was measured, and the adhesiveness was judged according to the following criteria. Note that a higher adhesive strength indicates better adhesiveness.
◎: Adhesive strength is 30N/15mm or more. ○: Adhesive strength is 25N/15mm or more and less than 30N/15mm. △: Adhesive strength is 20N/15mm or more and less than 25N/15mm. ×: Adhesive strength is less than 20N/25mm.

<Tackiness>
An adhesive tape (one side of which was backed with a PET film (100 μm thick)) processed into a shape of 15 mm × length 100 mm × thickness 1 mm was obtained as a test piece. The adhesive side of this test piece (the side not backed with the PET film) was measured for tack using a probe tack tester (probe diameter 25 mm ² , thrust stop time 0.1 sec, thrust speed 10 mm/sec, load: 9.8 g) manufactured by Nichiban Co., Ltd., and the tack (stickiness) was judged according to the following criteria.
◎: Probe tack value is 5N/25mm2 or ^more . ○: Probe tack value is 4N/25mm2 ^or more and less than 5N/25mm2 ^. △: Probe tack value is 2N/25mm2 ^or more and less than 4N/25mm2 ^. ×: Probe tack value is less than 2N/25mm2 ^.

<Creep resistance (holding force/shear force)>
An adhesive tape (without a PET film) processed to a shape of 25 mm wide x 80 mm long x 1 mm thick was attached between two stainless steel plates (SUS304: 100 mm x 30 mm x 2.5 mmt), one of the stainless steel plates was fixed, and a 200 g weight (weight) was hung from the other stainless steel plate (see FIG. 1A), and the plate was left for 1 hour in an environment of 50°C. Then, the amount of displacement (distance of slippage) of the other stainless steel plate relative to the one stainless steel plate after leaving the plate for 1 hour was measured (see FIG. 1B), and the creep resistance was evaluated according to the following criteria. The smaller the amount of displacement, the better the creep resistance.
◎: Misalignment is less than 2 mm. ○: Misalignment is 2 mm or more and less than 4 mm. △: Misalignment is 4 mm or more and less than 6 mm. ×: Misalignment is 6 mm or more, or falls.

Claims (9)

A butyl-based rubber pressure-sensitive adhesive composition comprising:
100 parts by mass of butyl rubber;
150 to 700 parts by mass of an inorganic compound;
20 to 300 parts by mass of a softener;
5 to 70 parts by mass of a fibrous organic compound;
A butyl-based rubber pressure-sensitive adhesive composition comprising: The butyl-rubber adhesive composition according to claim 1, wherein the inorganic compound contains 30% by mass or more of a clay mineral. The butyl-based rubber pressure-sensitive adhesive composition according to claim 1, wherein the average fiber length of the fibrous organic compound is 0.5 to 10 mm. An adhesive tape comprising the butyl rubber adhesive composition according to any one of claims 1 to 3. A waterproof sheet for roofs, comprising an adhesive layer containing the butyl-based rubber adhesive composition according to any one of claims 1 to 3, and a waterproof sheet laminated to the adhesive layer. A joint formed by joining a roof tile and a waterproof sheet with the butyl-based rubber pressure-sensitive adhesive composition according to any one of claims 1 to 3. An adhesive composition for fixing a toilet, which is used for fixing a toilet to a floor, using the butyl rubber adhesive composition according to any one of claims 1 to 3. A joint formed by joining a toilet bowl and a floor with the adhesive tape described in claim 4. A joint formed by joining a toilet and a floor with the adhesive composition for fixing a toilet according to claim 7.