JPS6231754B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel adhesive composition. The term "adhesive composition" used herein
refers to a composition that exhibits excellent adhesive performance before curing, and then hardens upon stimulation with light, radiation, heat, etc., and exhibits excellent adhesive properties. Conventionally, a typical example of the use of pressure-sensitive adhesives is so-called "adhesive tape." The method of manufacturing the adhesive used in this adhesive tape is to mix a large amount of tackifying agent such as tackifier into a base polymer such as rubber, acrylic, or silicone to make it sticky. There are two main methods: methods of imparting tackiness to the base polymer itself, and methods of imparting tackiness to the base polymer itself as described above. As adhesive tapes are put into practical use and used in various fields, high performance is required, and products with excellent physical properties are emerging, but these conventional adhesive tapes have creep properties at high temperatures and unevenness on adherends. If there is a surface, there is a problem in following this, etc.
The reality is that it has hardly been applied to places that require such performance. As a result of intensive research to improve various deficiencies in conventional adhesives, the present inventors have found a good balance between tack and adhesion, high temperature creep resistance, deterioration resistance, such as weather resistance and water resistance. The present inventors have discovered a pressure-sensitive adhesive composition that has excellent heat resistance, moisture resistance, etc., and is also applicable to adherends having uneven surfaces, and has completed the present invention. The adhesive composition according to the present invention is of a crosslinking reaction type, and contains (A) 100 parts by weight of conjugated diene butyl rubber or halogenated butyl rubber, (B) 50 to 400 parts by weight of a tackifier, and ( C) It is characterized by comprising 5 to 50 parts by weight of a polymerizable unsaturated compound containing an acryloyl or methacryloyl group. Component (A) used as the base polymer in the composition according to the present invention is a halogenated butyl rubber obtained by halogenating an isobutylene-isoprene copolymer or a conjugated diene butyl rubber obtained by further dehydrohalogenating the halogenated butyl rubber. It is. Furthermore, this (A) component polymer has a general formula in its molecule.

【formula】

【formula】 or

[Formula] (In the formula, X represents a halogen atom, R ₁ , R ₂ , R ₃
each represents a hydrogen atom or a hydrocarbon residue having 1 to 10 carbon atoms, n represents an integer of 2 to 5, and m represents 1 to 10.
4 and l is an integer from 1 to 30), which increases the crosslinking rate,
Heat resistance and adhesive performance can be improved. The tackifier which is component (B) is a liquid tackifier such as liquid polybutene, liquid polyisobutylene, liquid polypentene, liquid polyisobutylene-isoprene, liquid polyisobutylene-butadiene, aliphatic petroleum resin, aromatic type, etc. A tackifier that is a petroleum-based hydrocarbon resin such as a petroleum resin or an alicyclic petroleum resin is preferable, but there is no problem in using a natural-based tackifier. Component (C) is selected from acrylic acid, methacrylic acid and derivatives thereof. The most common derivatives are esters and amides. Examples of alcohol residues in esters include methyl group, ethyl group,
In addition to alkyl groups such as dodecyl, stearyl, and lauryl, cyclohexyl, tetrahydrofurfuryl, aminoethyl, 2-hydroxyethyl, 3-hydroxyethyl, and 3-chloro-2-hydroxypropyl groups etc. Esters with ethylene glycol, triethylene glycol and polyethylene glycol are also used. A typical example of the amide is diacetone acrylamide. The above main components (A) to in the composition according to the present invention
(C) is 50 to 400 parts by weight per 100 parts by weight of component (A).
Component (B) is blended with 5 to 50 parts by weight of component (C). In addition to the above-mentioned main components, the composition according to the present invention includes fillers, softeners, photosensitizers, crosslinkers, anti-aging agents,
Adhesion promoters and the like can be added. Carbon black, calcium carbonate, silica, etc. can be used as fillers. Of course, these fillers are added with consideration given to not substantially inhibiting curing. Photosensitizers added to adjust the curing rate in the case of photocrosslinking include benzoin, benzophenone, benzoisoethyl ether, benzoinpropyl ether, benzoin isobutyl ether, dibenzyl, 5-nitroacenaphthene, hexachlorocyclopentadiene, p-nitrodiphenyl, p-nitroaniline, 2,4,6-trinitroaniline, 1,2-benzanthraquinone,
Examples include 3-methyl-1,3-diaza-1,9-benzathrone, benzyl, benzanthrone, 1-naphthaldehyde, anthraquinone, camphorquinone, biacetyl, 2,3-pentadione, etc. % or less. Furthermore, other sensitizers include p-dimethylaminobenzaldehyde, Michler's ketone, diethanolamine, triethanolamine, 4,
4'-methylenebis(N,N-dimethylaniline)
Amino compounds such as the above can be used in combination with the carbonyl photosensitizer, and in this case also, they are added in a proportion of 10% by weight or less. Photocrosslinking does not necessarily require ultraviolet light; light in the visible region can be used for the curing reaction depending on the selection of the photosensitizer. Up to 5% by weight of a polymerization inhibitor can be added to increase storage stability, and for this purpose hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, methylhydroquinone,
2-t-butylhydroquinone, phenothiazine, p-phenylenediamine, 2,6-di-t-
Butylphenol, 2,6-di-t-butyl-p
-cresol, tri(mixed mono- and dinonylphenyl) phosphorite, aldol-α-naphthylamine, etc. are selected. In the case of thermal crosslinking, sulfur, peroxide, metal oxide, etc. can be used. Known silane coupling agents can be used as adhesion promoters, which are added in an amount of up to 10% by weight. Silane coupling agents include γ-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyl-tris(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4 -Ethoxycyclohexyl)ethyl-trimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β-(aminoethyl)- Examples include γ-aminopropyltrimethoxysilane. In addition, when component (A) is modified to contain an α,β-unsaturated carboxylate group and a halogen atom in the molecule as described above, zinc,
A crosslinking reaction can be easily carried out by adding a metal compound such as iron or magnesium. The composition according to the present invention can be produced by kneading the various components listed above using a roll mill, a kneader, a Burberry mixer, or the like. Furthermore, this kneaded product can be molded into a certain shape. For example, by extruding the kneaded product into a plate shape using a press, sandwiching it with release paper, and then press-molding it, an adhesive sheet can be obtained. When the composition according to the present invention is spread between adherends, it functions as a good adhesive in an uncrosslinked state before curing, and acts on adherends made of almost all materials,
Even if there are irregularities on the surface of the adherend, no voids are created, and the adhesive layer is then cured by a crosslinking reaction due to energy such as light, radiation, heat, etc., and the adhesive layer changes to an adhesive layer, which allows the adherends to bond to each other. Bond firmly. Furthermore, the cured adhesive layer exhibits good rubber elasticity, so
Even when vibration is applied to the adherend, there is a very low possibility that dynamic fatigue will occur due to this vibration.
Rather, it works to absorb stimuli such as vibrations. Next, the present invention will be explained in more detail with reference to production examples and performance test examples. Production Example 1-3, Comparative Example 1-2 and Test Example The ingredients shown in Table 1 below were loaded into a kneader and kneaded at room temperature, then the kneaded product was extruded through a press at 70°C and sandwiched with release paper. The pressure-sensitive adhesive sheets of Compositions A to C and Comparative Composition 1 were prepared by molding them into sheets with a thickness of 1 mm. Comparative Composition 2 shows a formulation example of a pressure-sensitive adhesive for a general acrylic pressure-sensitive adhesive tape, and the pressure-sensitive adhesive tape using this composition as a pressure-sensitive adhesive contains butyl acrylate and 2-acrylic acid. Ethylhexyl, methyl methacrylate, benzoyl peroxide, and ethyl acetate were charged into a reaction vessel in the proportions shown in Table 1,
A copolymer was obtained by reacting at 70°C for 6 hours in a nitrogen atmosphere, and 1 g of tolylene diisocyanate was added and mixed to 100 g of this polymerization solution.The resulting adhesive was then mixed with a 1 mm thick sponge rubber. This adhesive layer was coated on both sides of the sheet to a thickness of about 0.1 mm, and the sheet was heated at 120° C. for 10 minutes to cause crosslinking.

[Table] Performance test As the adherend, an aluminum test piece (thickness
1.6 mm, width 25 mm, length 120 mm) and 6-nylon (Toray CM-1021) sheet (thickness 1.0 mm, width 25
mm, length 100 mm) was used. After washing these adherends with acetone, each of the above-mentioned pressure-sensitive adhesive compositions (cut into pieces having a width of 25 mm and a length of 15 mm) was inserted between each test piece and bonded together. The shear force of the test pieces of Compositions A, B, C and Comparative Composition 1 was measured in the uncrosslinked state and expressed as adhesive strength. Then, using a 4KW high-pressure mercury lamp, a 6- An adhesion test piece was prepared by irradiating the nylon film side for 20 seconds. On the other hand, as the adherend having an uneven surface, a float glass with a thickness of 5 mm with a step of 0.2 mm in depth was used, and between this adherend and the 6-nylon film adherend, compositions A to The sheets of C and Comparative Composition 1 were sandwiched together and irradiated from the 6-nylon film side with the aforementioned high-pressure mercury lamp for 20 seconds to prepare a test piece. For the adhesive tape using Comparative Composition 2 as an adhesive, only pressure-sensitive adhesion was performed and no ultraviolet crosslinking was performed. Adhesion was tested using a tensile tester at a tensile speed of 10 mm/
It was evaluated by measuring the shear force at 25°C and 80°C. Durability is heat resistance (100℃ x 30 days), humidity resistance [50
°C (95% RH) x 30 days] and water resistance (40°C warm water immersion x 30 days) and evaluated by the rate of decline after these deterioration tests. Adhesion to uneven surfaces is determined by observing the bonded area on the glass surface and determining whether it completely fills in the gaps.
The peel force was measured and evaluated at ℃. The results are shown in Table 2.

[Table] Production Example 4 and Test Examples After masticating 100 g of conjugated diene butyl rubber in a roll mill at a temperature of 50°C, 2.9 g of methacrylic acid (1 mole of methacrylic acid per 3000 parts of conjugated diene butyl rubber) was added dropwise and mixed, and further t-butyl hypo 3.65 g of chloride (equivalent mole to methacrylic acid) was added and mixed, and kneading was continued for about 10 minutes to cause a reaction, thereby obtaining a modified conjugated diene butyl rubber. The rubber after the reaction was dissolved in toluene, then poured into methanol, the precipitated polymer was collected, dried, and further dissolved in toluene. The infrared absorption spectrum of this solution is 1710 cm ^-1 based on carbonyl group and ester group (

It showed an absorption of 1160 cm ^-1 based on [Formula]. This modified conjugated diene butyl rubber was kneaded in a kneader at the compounding ratio shown in Table 3, and then pressed to produce an adhesive sheet with a thickness of 1 mm. Table 3 Composition D Modified conjugated diene butyl 107g Polybutene 150 Silica 20 1,3-butylene dimethacrylate 20 γ-methacrylopropyltrimethoxysilane
1 Benzoin isopropyl ether 2 2,6-di-tertiary-butyl-p-cresol
0.5 In order to examine the crosslinking speed of Composition A and Composition D of Production Example 1 by ultraviolet rays, the irradiation time, adhesive strength, and high temperature adhesive performance were measured, and the results are shown in Tables 4 and 5. An aluminum plate and a 6-nylon sheet were used as adherends, and a test piece was prepared by irradiating the 6-nylon side with a 4KW high-pressure mercury lamp at a distance of 15 cm.

【table】

[Table] Crosslinking Composition D 15Kg/cm ² 4KW x 20 seconds irradiation From the above results, it can be seen that performance, such as crosslinking speed and high temperature adhesive strength, is better when modified conjugated diene butyl rubber is used as the base polymer. . Production Examples 5-11, Comparative Example 3, and Test Examples The components shown in Table 6 below were loaded into a kneader, and adhesive sheets corresponding to compositions E to K were prepared by the methods described in Production Examples 1 to 3. Created. The purpose of these examples is to investigate the effect on adhesive performance when changing the amount and type of component (C), that is, the polymerizable unsaturated compound blended into the adhesive composition, and therefore, for comparison. As composition 3, a composition not containing this component (C) was selected. Table 6 also shows the results of the adhesion and adhesion performance tests, and the adherends used were aluminum plates and 6-nylon sheets, as in the tests related to Production Examples 1 to 3.

[Table] Production Examples 12 to 16 and Test Examples Production Examples 1 to 1 using the ingredients shown in Table 7 below
Pressure-sensitive adhesive sheets corresponding to compositions LP were prepared by the method described in 3. These examples are intended to investigate the effect on adhesive performance of changing the amount and type of tackifier blended in an adhesive composition, and include the preparation of test pieces and crosslinking method. Measurements of adhesion and adhesion were carried out in accordance with the tests conducted in connection with Production Examples 1 to 3. The results are also shown in Table 7.

[Table] From the results in Table 7, it can be seen that compositions L to P all have well-balanced tackiness and adhesive properties and are excellent as pressure-sensitive adhesives. Production Example 17 and Test Examples Using the methacrylic acid-modified conjugated diene butyl mentioned in Production Example 4 as a base polymer, various components were loaded into a kneader in the proportions shown in Table 8.
A pressure-sensitive adhesive sheet corresponding to Composition Q was prepared by the method described in Section 3. The adhesive force was measured in an uncrosslinked state by sandwiching this adhesive sheet between aluminum test pieces as adherends, and the adhesive force was measured after thermal crosslinking at a temperature of 80 to 160°C. are also shown in Table 8.

【table】

[Table] Production Examples 18 to 22 and Test Examples Using the methacrylic acid-modified conjugated diene butyl mentioned in Production Example 4 as a base polymer, various components were loaded into a kneader at the compounding ratios shown in Table 9, kneaded, and then pressed. Adhesive sheets corresponding to compositions R to V with a thickness of 1 mm were prepared. These pressure-sensitive adhesives undergo a crosslinking reaction when exposed to light with a wavelength of 400 nm or more, and exhibit good adhesive performance. As a light source, a 150W halogen lamp having an effective wavelength in the near-ultraviolet-visible region and direct sunlight irradiation were used separately. The measurement of adhesive strength was carried out according to the tests conducted in connection with Production Examples 1 to 3. An aluminum plate and a 6-nylon sheet were used as the adherends, and the test piece was prepared by irradiating light from the 6-nylon side. The results are also shown in Table 9.

【table】

Claims (1)

[Claims] 1 Main components: (A) 100 parts by weight of conjugated diene butyl rubber or halogenated butyl rubber (B) 50 to 400 parts by weight of tackifier (C) Polymerizable unsaturated compound containing acryloyl or methacryloyl group 5 to An adhesive composition comprising 50 parts by weight. 2 (A) Component has the general formula [Formula] [Formula] or [Formula] (in the formula, X represents a halogen atom, and R ₁ , R ₂ , R ₃
each represents a hydrogen atom or a hydrocarbon residue having 1 to 10 carbon atoms, n represents an integer of 2 to 5, and m represents 1 to 10.
Claim 1, characterized in that it has an α,β-unsaturated carboxylate group represented by (representing an integer of 4 and l represents an integer of 1 to 30).
The composition described in Section.