JP2566562B2 - Adhesive composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pressure-sensitive adhesive composition having a good balance between tackiness and cohesive force and excellent low-temperature tackiness.

(Prior Art) In order to obtain a medicinal effect on the whole body or a local area, an adhesive patch containing a drug (physiologically active substance) in an adhesive layer is applied to the skin surface and the drug is absorbed through the skin. It is being appreciated. Adhesives are also contained in surgical plasters, adhesive drapes, and adhesive dressings. In addition, various labels, stickers, wallpaper, flooring, etc. are often attached using adhesives or adhesives. An adhesive tape (for example, cellophane tape, vinyl tape for electrical insulation) and an adhesive sheet having an adhesive layer on the back surface are also used in many fields.

The pressure-sensitive adhesive composition used for these pressure-sensitive adhesive layers includes
For example, rubber-resin blends obtained by blending natural polyisoprene rubber, synthetic polyisoprene rubber, styrene-butadiene rubber, etc. with an adhesive resin, an oil softener, etc .; acrylic ester polymer, acrylic ester-methacrylic ester copolymer Acrylic polymers such as; polyvinyl ether mixtures; polyisobutylene mixtures.

However, these adhesive compositions have a glass transition point of −60.
The temperature is above ℃, and most of them are -45 ℃ to -30 ℃, and the adhesiveness at low temperature is low. Therefore, it is not suitable for use in cold regions. Even outside the cold regions, in winter, the tackiness decreased below 10 ° C,
If the temperature is lower than ℃, tackiness is significantly lost. Furthermore, it has almost no stickiness below -10 ° C. Therefore, it cannot be used.

In order to solve such drawbacks, a softening agent, for example, is blended in a high content as a pressure-sensitive adhesive composition having excellent low-temperature tackiness. However, these are normal temperature (20 ~
At a temperature of 30 ° C) or higher, the cohesive force is significantly reduced. For this reason, in patches, pressure-sensitive adhesive tapes, pressure-sensitive adhesive sheets, etc. containing these compositions in the pressure-sensitive adhesive layer, the pressure-sensitive adhesive composition is likely to remain on the surface to be adhered upon peeling (adhesive residue phenomenon). A pressure-sensitive adhesive composition having excellent low-temperature adhesiveness and a good balance between adhesiveness and cohesive strength has not yet been disclosed.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a pressure-sensitive adhesive composition having excellent low-temperature adhesiveness. Another object of the present invention is to provide a pressure-sensitive adhesive composition which is excellent in low-temperature adhesiveness and has a good balance between adhesiveness and cohesive force. Still another object of the present invention is to provide an adhesive composition having no skin irritation. Still another object of the present invention is to provide a pressure-sensitive adhesive composition having excellent electric insulation. Still another object of the present invention is to provide an adhesive composition capable of forming an adhesive layer with a small amount of solvent.

(Means for Solving Problems) In the present invention, the low-temperature adhesiveness of the adhesive has a glass transition point (Tg
Adhesives with a low glass transition point are excellent in low-temperature adhesiveness; when a butadiene polymer mainly composed of 1,4-cis bonds and an adhesive resin are combined, an extremely low glass transition point is obtained. Low temperature tackiness is improved; when polyisoprene rubber and / or polyisobutylene rubber is added thereto at a constant ratio, the glass transition point can be kept low and the low temperature tackiness can be maintained while the cohesive force at room temperature is increased; As a result, it is possible to provide a pressure-sensitive adhesive composition having both low-temperature adhesiveness, cohesive strength and adhesiveness at room temperature, which have not been heretofore considered;
It was completed based on the knowledge of the inventor.

The pressure-sensitive adhesive composition of the present invention comprises a butadiene polymer having a 1,4-cis bond content of 90% or more, a polyisoprene rubber, and / or
Alternatively, it contains a polyisobutylene rubber and an adhesive resin in a specific ratio and has a glass transition point of −70 ° C. or lower, whereby the above object is achieved.

The pressure-sensitive adhesive composition has a glass transition point adjusted to -70 ° C or lower. Above -70 ° C, the desired low temperature tackiness of the adhesive composition cannot be obtained.

The 1,4-cis bond of the butadiene polymer is adjusted to 90% or more, preferably 93% or more. The average molecular weight (weight average) of the butadiene polymer is 30,000 to 100,000, and the glass transition point (Tg point) is -95 ° C or lower, preferably -100 ° C to -1.
10 ℃ This butadiene polymer is a lump or a rubber at room temperature. Mooney viscosity (ML1 + 4,100 ℃) is 25 ~
50, and viscosity in 5% toluene solution (20 ℃) is 30 ~ 200
A range of cps is preferred. Examples of commercially available butadiene polymers include JIS BR-01 and JSR BR manufactured by Japan Synthetic Rubber Co., Ltd.
−02, JSR BR-02L, JSR BR-02LL, Nipo made by Zeon Corporation
BR-1220, UBEPOL-BR-100, UBEPOL-B made by Ube Industries
R-130B, UBEPOL-BR-150, UBEPOL-BR-150B, UBEPOL-B
There is R-153A.

Examples of the polyisoprene rubber include natural rubber and synthetic cis-1,4-polyisoprene rubber (synthetic natural rubber). Natural rubber is mainly composed of -cis-1,4-polyisoprene, and its molecular weight varies from tens of thousands to several millions or more. As commercial products of natural rubber, for example, 1,4-cis bond of synthetic cis-1,4-polyisoprene having pale crepe and mode sheet is prepared at 90 to 98%. The average molecular weight of this synthetic cis-1,4-polyisoprene rubber is about 10
10,000 to 5 million, and Mooney viscosity (ML1 + 4,100 ℃) is 70
That is all. Examples of commercially available synthetic cis-1,4-polyisoprene include JSR IR-220 manufactured by Japan Synthetic Rubber Co., Ltd.
0, Sumika IR-2200 manufactured by Sumitomo Chemical Co., Ltd., Kurapren-IR-10 manufactured by Kuraray Co., Ltd., Nipol IR-2200 manufactured by Zeon Corporation, BF Ameripol-SN-600, Ameripol-SN manufactured by Goodrich Chemical Co., Ltd. -606, Goodyear Nut Shin 2200,
There are Califlex IR-305 and Califlex IR-307 manufactured by Shell Oil Co., Ltd.

Polyisobutylene rubber is highly elastic and has an average molecular weight (number average) in the range of 50,000 to 500,000. Commercially available products of polyisobutylene rubber include Vistanex MM-L-80, Vistanex MM-L-100, Vistanex MM-L-200 manufactured by Exxon, and Opanol B-8 manufactured by BASF.
0, Opanol B-120, and Opanol B-200.

Examples of the adhesive resin include rosin resins such as rosin, polymerized rosin, rosin-glycerin ester, rosin-pentaerythritol ester and hydrogenated products thereof; β-pinene polymer, α-pinene polymer, modified pinene polymer And terpene-based resins such as mixed pinene polymers;
Indene resins and xylene resins - coumarone; terpene-modified phenol; C ₅ aliphatic petroleum resin having an unsaturated bond from petroleum fractions -C _9, alicyclic petroleum resins, aromatic petroleum resins; coumarone resin. Rosin resin and terpene resin are particularly preferable. The softening temperature of the adhesive resin is 150 ° C, preferably 50 to 150 ° C.

Polyisoprene rubber and / or polyisobutylene rubber is contained in the range of 20 to 120 parts by weight to 100 parts by weight of butadiene polymer having 90 or more 1,4-cis bonds, and the butadiene polymer and polyisoprene rubber The adhesive resin is contained in an amount of 20 to 120 parts by weight based on 100 parts by weight of the polyisobutylene rubber. When the amount of polyisoprene rubber and / or polyisobutylene rubber is less than 20 parts by weight, the cohesive force of the pressure-sensitive adhesive composition decreases. 12
If it exceeds 0 part by weight, the desired low temperature tackiness of the pressure-sensitive adhesive composition cannot be obtained. When the amount of the adhesive resin is less than 20 parts by weight, the desired low-temperature adhesiveness of the adhesive composition cannot be obtained, and when it exceeds 120 parts by weight, the cohesive force of the adhesive composition is reduced.

The pressure-sensitive adhesive composition of the present invention may further contain a softener, an antioxidant, a filler, a pigment, a coloring agent, a fragrance, and a surfactant.

The softening agent is added for the purpose of further improving the tackiness of the pressure-sensitive adhesive composition or improving the insulating property. Examples of softening agents include diethyl phthalate, dioctyl phthalate, tricresyl phosphate, process oils (particularly paraffinic, naphthenic and aromatic), tall oil, cottonseed oil, olive oil, peanut oil, natural squalane, synthetic squalane. , Low viscosity polyisobutylene or polybutadiene.

Anti-aging agents include known anti-aging agents used for natural rubber and styrene-butadiene rubber (SBR),
For example, 2,6-di-t-butyl-p-cresol, 2,2'-
There are phenolic antiaging agents such as methylenebis (4-methyl-6-t-butylphenol) and styrenated phenol, and 2,5-di-t-amylhydroquinone.

The filler is added for the purpose of imparting thixotropy to the pressure-sensitive adhesive composition, improving electrical properties, and the like. Fillers include, for example, calcium carbonate, surface modified calcium carbonate, silicic acid anhydride, kaolin, clay, calcium sulfate. Pigments include zinc white and titanium white.

The pressure-sensitive adhesive composition thus obtained is used to produce a pressure-sensitive adhesive tape or pressure-sensitive adhesive sheet, for example, as follows.

Butadiene polymer having 1,4-cis bond content of 90% or more, polyisoprene rubber and / or polyisobutylene rubber,
The adhesive resin and additives are dissolved in an organic solvent to prepare a solution of the adhesive composition. As the organic solvent, for example, toluene, cyclohexane, tetrahydrofuran, heptane, n-hexane, carbon tetrachloride, trichlene, etc. may be used alone or in combination. The concentration of the adhesive composition solution is
From the viewpoint of viscosity suitable for coating, the viscosity should be 4000-40000c.
ps (typically 25-50%) is used. If necessary, the viscosity of the adhesive composition solution is adjusted by defoaming or leaving it for a certain period of time. Next, this solution is, for example, transfer-coated on the base sheet anchored with the undercoating agent to form an adhesive layer. Examples of the undercoating agent include natural rubber-methyl methacrylate graft copolymer,
There is a butyl rubber-vinyl acetate-maleic anhydride graft copolymer. The base material may be subjected to corona discharge treatment before the anchor treatment. If necessary, the surface of the base material opposite to the anchor-treated surface is subjected to a peeling treatment. After coating, it is dried to remove the organic solvent. further,
After the coated surface is protected with silicone release paper or the like, the adhesive tape or sheet is obtained by winding it into a roll or cutting it into an appropriate size.

In order to use the pressure-sensitive adhesive tape or pressure-sensitive adhesive sheet obtained from the pressure-sensitive adhesive composition of the present invention as a medical patch, the composition contains a drug. Drugs include, for example, cardiovascular drugs, vasodilators, anti-inflammatory drugs, analgesic and anti-inflammatory drugs, anti-allergic drugs, antihistamines, steroid hormones, blood pressure lowering agents, bactericidal agents
There are antibacterial agents, diuretics, local anesthetics, sedatives, antipyretics, sleeping agents, psychostimulants, tranquilizers, antitussives, antispasmodics, asthma drugs, antitencan drugs, anticancer drugs, and hemolytic agents.

(Function) As described above, the pressure-sensitive adhesive composition of the present invention comprises a butadiene polymer (cis-1,4-butadiene polymer) having a 1,4-cis bond content of 90% or more, a polyisoprene rubber and / or a polyisoprene rubber. It contains isobutylene rubber and adhesive resin in specific proportions and has a glass transition point of -70 ° C or less, so it has excellent low-temperature adhesiveness (eg, adhesiveness of -10 ° C or less) and a balance between adhesiveness and cohesive strength. Is maintained. The compatibility of each component is also good, giving a single glass transition point.

When a combination of cis-1,4-butadiene polymer and adhesive resin is combined, a remarkably low glass transition point is obtained and low temperature adhesiveness is improved. Even if polyisoprene rubber and / or polyisobutylene rubber having a high glass transition point is added thereto, surprisingly, the glass transition point is kept low and the low temperature tackiness is maintained. Moreover, the cohesive force at room temperature is improved, and the adhesive residue phenomenon does not occur. Does not affect the room temperature tackiness.

With cis-1,4-butadiene polymer and adhesive resin alone,
Although it has a low glass transition point and low-temperature adhesiveness, it has low cohesive strength at room temperature. Only the polyisoprene rubber and / or polyisobutylene rubber and the adhesive resin have a high glass transition point and lack adhesiveness (including low-temperature adhesiveness). Not only does the cis-1,4-butadiene polymer and polyisoprene rubber and / or polyisobutylene rubber lack adhesiveness, the compatibility of both components is poor, and a single glass transition point is not exhibited.

If the contents of the cis-1,4-butadiene polymer, the polyisoprene rubber and / or the polyisobutylene rubber and the adhesive resin are significantly changed, the properties of the adhesive composition deteriorate. As the proportion of cis-1,4-butadiene polymer increases,
The cohesive force of the pressure-sensitive adhesive composition decreases. When the proportion of the polyisoprene rubber and / or polyisobutylene rubber or the adhesive resin increases, not only the low temperature adhesiveness but also the adhesiveness at room temperature decrease.

(Examples) The present invention will be described below with reference to Examples.

Example 1 (1) Preparation of pressure-sensitive adhesive composition cis-1,4-polybutadiene (1,4-cis bond is 97%, JSR
BR-01, manufactured by Japan Synthetic Rubber Co., Ltd. 65 parts by weight Natural rubber (peel crepe) 35 parts by weight Terpene resin (softening point 100 ° C, Piccolite-S-100,
Hercules) 60 parts by weight 2,5-di-t-amylhydroquinone (antiaging agent) 1.5 parts by weight The above formulation was dissolved in cyclohexane at a concentration of 25% by weight to obtain a solution of an adhesive composition. The glass transition point of the pressure-sensitive adhesive composition obtained by applying and drying the solution of this pressure-sensitive adhesive composition was -105 ° C as measured by the DSC method. This adhesive composition is used for adhesive drapes, adhesive dressings, medical tapes such as plasters, stationery such as cellophane tape and acetate tape, light packaging tapes, adhesive seals and adhesive labels.

(2) Preparation of cellophane tape Cellophane having a width of 50 cm and a thickness of 40 μm was used as a base material.
This cellophane contains 7% by weight of glycerin as a moisturizer.
It was contained. Anchor treatment was applied to this base material with an undercoating agent composed of a butyl rubber-vinyl acetate-maleic anhydride graft copolymer. Undercoating agent is butyl rubber
It was obtained by graft-copolymerizing 5 parts by weight of vinyl acetate and 5 parts by weight of maleic anhydride in a solution containing 90 parts by weight. Anchor treatment is performed by adding 4 g of this copolymer solution onto the substrate.
Gravure coating was performed in an amount of / m ² (coating amount after drying). On the other hand, a dilute solution of polyoctadecylethyleneurea (equimolar addition reaction product of polyethyleneimine and ocdecylisocyanate, a stripping agent) was applied to the surface of the base material opposite to the anchor-treated surface, and the weight after drying was 0.02 g. Peeling treatment was performed so that

The solution of the adhesive composition obtained in (1) was applied to the anchor-treated surface of the base material to prepare a cellophane tape having an adhesive layer with a thickness of 25 μm. 20m of this cellophane tape
The above is wrapped around a cylindrical paper core with a diameter of 3 inches, and the width is 15
A cellophane tape roll was produced by cutting into a mm-shaped slice.

(3) Evaluation of physical properties of cellophane tape The physical properties of the cellophane tape obtained in (2) were evaluated as follows. Table 1 shows the results.

(A) Peeling method adhesive strength test Cellophane tape was cut into 15 cm lengths to obtain tape-shaped samples. This tape-shaped sample is sandpaper (# 28
Approx. 7c on the surface of a stainless steel plate (thickness: approx. 0.2 cm) polished with 0)
Stick it over the length of m and use a 2 kg rubber roller,
I crimped back and forth once. After crimping, leave at 21 ℃ for 30 minutes or more, then fold one end 180 ° and perform constant speed forced peeling at 300 mm / min, and measure the adhesive strength at this time (JIS-Z-152
2). As a result, the adhesive strength was 480g / 15mm width at 20 ℃.
The same adhesive strength test was conducted at 5 ℃, 0 ℃, -5 ℃, -10 ℃ and 40 ℃. It was 530g / 15mm width at 5 ℃ and 6410g at 0 ℃.
/ 15mm width, 710g / -15mm width at -5 ℃, 790 / 15mm at -10 ℃
Width, and 340g / 15mm width at 40 ℃.

(B) Holding power test Cellophane tape was cut into a length of 10 cm to obtain a tape-shaped sample. Use one end of this sample with sandpaper (# 280)
The edges of a stainless steel plate (thickness: about 0.2 cm), which had been abraded by the above method, were put side by side, and a 2 kg rubber-rolled roller was used to make one round trip at a speed of 30 cm / min. The adhesion area was 25 mm (length direction) x 15 m (width). Then, a load of 1000 g (total weight) was applied to the sample via a jig. The time (minutes) from the time when the load was applied until the tape dropped was evaluated as the holding power (JIS-Z-0237). As a result, this fall time is 2
It was 7 minutes at 0 ° C. When the same holding power test was conducted at 0 ° C, -5 ° C and 40 ° C, it was 51 minutes at 0 ° C, 110 minutes at -5 ° C, and 5 minutes at 40 ° C.

(C) Ball tack test Cellophane tape was cut into a length of 25 cm to obtain a tape-shaped sample. At room temperature, with the adhesive side of this tape-shaped sample outside
It was fixed on a 30 ° inclined surface. The non-adhesive film with a thickness of about 20 μm was covered from the upper part of the slope of the adhesive surface to the middle part downward. The ball bearing spheres, which were wiped clean, were transferred naturally from a point 100 mm above the boundary and onto the slope. The diameter of the largest sphere that spontaneously stops within 100 mm from the boundary line between the sticky surface and the non-sticky surface (1/32 inch unit, indicated by the number of molecules; for example, 17/32 inch is 17) Ball tack value (JIS-Z-023
7). As a result, the ball tack value was 26. 0 ℃,
When the same ball tack test was performed at -5 ℃, it was 0
It was 30 at ℃ and 20 at -5 ℃.

(D) Deployment force test When a cellophane tape roll was mounted on a freely rotating core and the tape was unwound at a speed of 60 m / min, the force applied to the core was used as an evaluation of the deployment force. Spreading power is 290g at 20 ℃
It was / 15 mm wide. The same deployment force test was performed at 0 ℃ and -5 ℃, and it was 430g / 15mm width at 0 ℃ and 560 at -5 ℃.
It was g / 15 mm wide. If the deployment force is too strong, it will be difficult to unwind, and if it is weak, it will be unwound naturally and the ease of use will decrease. The spreading force is preferably 100 to 500 g / 15 mm width.

Example 2 (1) Preparation of pressure-sensitive adhesive composition cis-1,4-polybutadiene (1,4-cis bond is 97% or more, Nipol BR-1220, manufactured by Zeon Corporation) 50 parts by weight Synthetic cis-1,4 -Polyisoprene rubber (average molecular weight 200
10,000, Sumika IR-2200, Sumitomo Chemical Co., Ltd.) 50 parts by weight Terpene-modified phenol resin (Schenectady-S-56)
6, Schenectady) 30 parts by weight Terpene resin (Piccolite S-100, β-pinene polymer,
Hercules) 40 parts by weight Tricresyl phosphate (softening agent) 30 parts by weight 2,6-di-t-butyl-p-cresol (antiaging agent)
2.5 parts by weight The above formulation was dissolved in a toluene / cyclohexane mixed solvent (weight ratio 1/1) at a concentration of 28% by weight to obtain a solution of an adhesive composition. The glass transition point of the pressure-sensitive adhesive composition obtained by applying and drying the solution of the pressure-sensitive adhesive composition was -88 ° C as measured by the DSC method. This pressure-sensitive adhesive composition has not only low-temperature adhesion but also excellent heat resistance and aging resistance, and good electric insulation. This composition is used for electrically insulating polyester tape and vinyl chloride tape.

(2) Production of polyester insulating tape As a base material, a polyester film (PET film) having a thickness of 38 μm stretched in two directions was used.

After treating this base material with corona discharge,
Methyl methacrylate graft copolymer (30% methyl methacrylate, Hevea Plus MG-30) was used as an undercoat.
Anchored. The anchor treatment was performed by gravure coating the solution of this copolymer on the substrate at an amount of 5 g / m ² (coating amount after drying). On the other hand, the surface of the base material opposite to the anchor treatment was subjected to a release treatment using the same release agent solution as in Example 1 so that the weight after drying was 0.02 g / m ² .

The anchor-treated surface of the substrate was coated with the solution of the adhesive composition obtained in (1) to prepare a polyester insulating tape having an adhesive layer with a thickness of 26 μm (± 2 μm). A polyester insulating tape roll was prepared by winding 10 m or more of this polyester insulating tape around a cylindrical paper core having a diameter of 3 inches and cutting it into a strip shape with a width of 19 mm.

(3) Evaluation of physical properties of polyester insulating tape The physical properties of the polyester insulating tape obtained in (2) are
It evaluated as follows. However, in addition to the normal state, the physical properties after the accelerated aging condition in which the tape roll was stored at 70 ° C for 30 days in the normal state were also evaluated. Table 2 shows the results.

(A) Adhesion Test "Adhesion by peeling method" (JIS-Z-1522, Example 1) for polyester tapes in normal state and after accelerated aging.
Adhesive force was measured by the same method as the above). As a result, the adhesive strength was 490 g / 19 mm width (normal state) and 480 g / 19 mm width (after accelerated aging) at 20 ° C. The same adhesive strength test was performed at 0 ℃, -5 ℃, and 10 ℃, and it was 610g / 19mm width (normal state) and 630g / 19mm width (after accelerated aging) at 0 ℃, and 7 at -5 ℃.
30g / 19mm width (normal) and 710g / 19mm width (after accelerated aging), and -10g 760g / 19mm width (normal) and 720
The width was g / 19 mm (after accelerated aging).

(B) Volume resistivity The polyester tape after normal aging and after accelerated aging was measured according to the method of "volume resistivity" (JIS-C-2336)
The volume resistivity at ° C was measured. As a result, the volume resistivity (20 ℃) is 2.4 × 10 ¹⁵ Ω · cm (normal state) and 2.2 × 10 ¹⁵ Ω.
-Cm (after accelerated aging).

(C) Breakdown voltage Regarding the polyester tapes under normal condition and after accelerated aging, the breakdown voltage at 20 ° C was measured by the method of "Insulation Breakdown Strength" (JIS-C-2338). As a result, the breakdown voltage (20 ℃) was 131 KV / mm (normal state) and 128 KV / mm (after accelerated aging).

(D) Electrolytic corrosion rate Regarding the polyester tape after accelerated aging, the electrolytic corrosion rate at 20 ° C was measured by the method of "electrolytic corrosion coefficient" (JIS-C-2338). As a result, the electrolytic corrosion rate (20 ° C) was 1.0.

Example 3 (1) Preparation of adhesive composition 1,4-polybutadiene (1,4-cis bond is 98%, UBEPOL BR
-100, Ube Industries Ltd. 50 parts by weight Synthetic cis-1,4-polyisoprene rubber (JSR IR-2200, Japan Synthetic Rubber Co., Ltd.) 20 parts by weight Polyisobutylene rubber (Vistanex MM-L-80, Exxon Co.) 30 parts by weight Terpene resin (softening point 100 ° C, YS resin PX-1000, manufactured by Yasuhara Yushi Co., Ltd.) 30 parts by weight Hydrogenated ester gum (ester gum H, manufactured by Arakawa Chemical Co., Ltd.)
30 parts by weight Liquid polyisobutylene (average molecular weight 3000, softening agent) 40 parts by weight 2,5-di-t-amylhydroquinone (antiaging agent) 2 parts by weight Cyclohexane / tetrahydrofuran mixed solvent (weight ratio 1/1) To obtain a solution of the adhesive composition. The glass transition point of the pressure-sensitive adhesive composition obtained by applying and drying the solution of this pressure-sensitive adhesive composition was -98 ° C as measured by the DSC method. This adhesive composition is used for adhesive tapes, medical tapes such as adhesive drapes, patches, new type adhesive patches, adhesive labels,
Used for adhesive seals.

(2) Preparation of plaster An adhesive preparation was prepared by adding the following drug (anti-inflammatory analgesic) to 100 parts by weight of the solid content of the adhesive composition obtained in (1).

Salocol 6 parts by weight Methyl salicylate 2 parts by weight l-Menthol 4 parts by weight d, l-camphor 0.7 parts by weight Thymol 0.07 parts by weight Glycyrrhetinic acid 0.4 parts by weight Diphenhydramine 0.02 parts by weight (3) Preparation of a new type of poultice A 140 μm non-plasticizer soft vinyl chloride film (Smedica V, Sekisui Chemical Co., Ltd.) was used.

This substrate was subjected to anchor treatment using the same copolymer as in Example 2 as an undercoat. The anchor treatment was performed by gravure coating the solution of this copolymer on the substrate at an amount of 5 g / m ² (coating amount after drying).

The solution of the plaster obtained in (2) was transfer-coated on the anchor-treated base material to form a new-type poultice having an adhesive layer with a thickness of 80 μm. The release paper used for transfer coating was attached to the adhesive layer and used as a protective release paper. The obtained new type poultice is used after being cut into, for example, a 5 cm × 7 cm square sheet.

(4) Evaluation of physical properties of new type poultices The physical properties of the new type poultices obtained in (3) were evaluated as follows.

(A) Peeling Method Adhesive Force Test By the same method as in Example 1, the adhesive force of the new type poultice was measured. As a result, the adhesive strength is 440g / 25mm width at 20 ℃,
The width was 490 g / 25 mm at 0 ° C.

(B) Adhesiveness The new type of poultice was cut into 4 cm x 4 cm and attached to the back of the subject one by one so as to be symmetrical. Paste 5
The subjects were symmetric, and the training was conducted during the daytime in summer for 6 hours. However, all did not perform violent movements. There was no case where all or part of the new poultice was peeled off 6 hours after application.

(C) Peelability When the new type poultice was peeled off 6 hours after application, it was peeled off with an appropriate stress, and there was no case where pain due to peeling was felt.

(D) Skin irritation No abnormalities were observed when skin abnormalities such as redness were observed at the application site one hour after the completion of application.

Comparative Example 1 Cyclohexane was blended with the following formulation as a natural rubber adhesive commonly used for high quality cellophane tape.
It was dissolved at a concentration of 20% by weight to obtain a solution of the adhesive composition.

Natural rubber (Pale crepe RSS ^# 20, passed through mastication roll 8 times) 100 parts by weight Terpene resin (softening point 100 ° C) 40 parts by weight Hydrogenated ester gum 40 parts by weight Process oil (aniline point 25 ° C) 10 parts by weight 1.5 parts by weight of 2,5-di-t-amylhydroquinone The glass transition point of this pressure-sensitive adhesive composition was -48 ° C as measured by the DSC method.

(2) Production of cellophane tape Using the solution of the pressure-sensitive adhesive composition obtained in (1), a cellophane tape was produced in the same manner as in Example 1.

(3) Evaluation of physical properties of cellophane tape The physical properties of the cellophane tape obtained in (2) were evaluated as follows. Table 1 shows the results.

(A) Peeling method adhesive strength test The adhesive strength of the cellophane tape was measured by the same method as in Example 1. As a result, the adhesive strength was 510 g / 15 mm width at 20 ° C. Adhesive strength is 650g / 15mm width at 5 ℃, 0-900 at 0 ℃
g / 15mm width, 30g / 15mm width at -5 ℃, 0g / 15mm at -10 ℃
The width was 390g / 15mm at 40 ℃.

(B) Holding power test The holding power of the cellophane tape was measured by the same method as in Example 1. As a result, the drop time (evaluation of holding force) is 2
It was 12 minutes at 0 ° C. 4 minutes at 0 ° C, 0 minutes at -5 ° C,
At 40 ° C, it took 8 minutes, and at 0 ° C and -5 ° C, peeling off occurred due to the interfacial fracture phenomenon.

(C) Ball tack test The ball tack value of cellophane tape was measured by the same method as in Example 1. As a result, the ball tack value is 20.
It was less than 4 at 28.0 ° C and less than 4 at -5 ° C.

(D) Spreading force test The spreading force of the cellophane tape was measured by the same method as in Example 1. As a result, the deployment force was 280g / 15mm width, 0 at 20 ℃.
It varies from 0 to 900g / 15mm width at ℃ and 0g / at -5 ℃.
It was 15 mm wide.

Comparative Example 2 (1) Preparation of pressure-sensitive adhesive composition As an acrylic pressure-sensitive adhesive usually used for polyester insulating tape, an acrylic copolymer having the following composition was used.

2-Ethylhexyl acrylate 65% by weight Butyl methacrylate 30% by weight Butyl acrylate 5% by weight The acrylic copolymer is a solution radical copolymer of the above acrylic monomer in ethyl acetate with an azobisisobutyronitrile catalyst. Obtained by polymerizing. The average molecular weight of this copolymer was about 480,000 by GPC method. The glass transition point (DSC method) was -42 ° C.

(2) Production of Polyester Insulating Tape A polyester insulating tape was produced in the same manner as in Example 2 using the solution of the pressure-sensitive adhesive composition obtained in (1).

(3) Evaluation of physical properties of polyester insulating tape The physical properties of the polyester insulating tape obtained in (2) are
It evaluated as follows. However, in addition to the normal state, the physical properties after accelerated aging conditions in which the tape roll was stored at 70 ° C for 30 days were also evaluated. Table 2 shows the results.

(A) Adhesive force test The adhesive force of the polyester insulating tape in a normal state and after accelerated aging was measured by the same method as in Example 2. As a result, the adhesive strength was 590g / 19mm width (normal state) and 620g / 19 at 20 ℃.
mm width (after accelerated aging), 430g / 19mm width (normal state) and 460g / 19mm width (after accelerated aging) at 0 ℃, 40g at -5 ℃
The width was / 19m (normal) and 80g / 19mm (after accelerated aging). 0g / 19m at -10 ℃ both in normal condition and after accelerated aging
It was m wide.

(B) Volume resistivity The volume resistivity of the polyester insulating tape in the normal state and after accelerated aging was measured by the same method as in Example 2. As a result, the volume resistivity (20 ℃) is 8.9 × 10 ¹⁵ Ω · cm (normal state)
And 8.8 × 10 ¹³ Ω · cm (after accelerated aging).

(C) Breakdown voltage The breakdown voltage of the polyester insulating tape under normal conditions and after accelerated aging was measured by the same method as in Example 2. As a result, the breakdown voltage (20 ℃) is 118KV / mm (normal) and 117KV / mm.
mm (after accelerated aging).

(D) Electrolytic Corrosion Rate The electrolytic corrosion rate of the vinyl tape after accelerated aging was measured by the same method as in Example 2. As a result, the electrolytic corrosion rate (20 ℃) is
It was 1.0.

Comparative Example 3 (1) Preparation of pressure-sensitive adhesive composition As a pressure-sensitive adhesive commonly used in new-type poultices, the following formulation was blended and dissolved in toluene at a concentration of 70% by weight,
A solution of the adhesive composition was obtained.

Styrene-butadiene-styrene (SBS type) teleblock copolymer (Califlex TR-1101, Shell Petroleum Co., Ltd.) 10 parts by weight Styrene-isoprene-styrene (SIS type) teleblock copolymer (Calflex TR-1107, Shell Petroleum Co., Ltd.) 30 parts by weight Liquid paraffin 150 parts by weight The glass transition point of this pressure-sensitive adhesive composition was measured by DSC method and was -69 ° C.

(2) Preparation of plaster A plaster was prepared by adding the same agent as in Example 3 to 100 parts by weight of the solid content of the pressure-sensitive adhesive composition obtained in (1).

(3) Preparation of new type poultice A new type poultice was produced in the same manner as in Example 3 using the solution of the plaster obtained in (2).

(4) Evaluation of physical properties of new type poultices The physical properties of the new type poultices obtained in (3) were evaluated as follows.

(A) Peeling Method Adhesive Strength Test By the same method as in Example 3, the adhesive strength of the new type poultice was measured. As a result, the adhesive strength was 20 g / 25 mm width at 20 ° C and 40 g / 25 mm width at 0 ° C.

(B) Adhesiveness In the same manner as in Example 3, the adhesiveness of the new type poultice was evaluated. As a result, peeling was observed in 7 of the 10 patches applied.

(C) Peelability In the same manner as in Example 3, the new type poultice was applied for 6 hours and then peeled off very lightly.

(D) Skin irritation In the same manner as in Example 3, the skin abnormality such as redness was observed at the applied site one hour after the new type patch was peeled off (that is, after the application was finished), and no abnormality was found. I couldn't do it.

As is clear from Examples and Comparative Examples, the pressure-sensitive adhesive composition of the present invention has excellent low-temperature adhesiveness. Good balance between tackiness and cohesive strength. The cellophane tape produced using this composition has a high peeling adhesive strength, holding power, ball tack value, and excellent adhesiveness not only at room temperature but also at low temperature. At low temperature, tackiness is improved compared to normal temperature. Adhesion is less likely to decrease even at high temperatures, which is preferable. It also has suitable spreading power as cellophane tape. Although the cellophane tape using the conventional natural rubber-based adhesive has the same adhesiveness / spreading power at room temperature or high temperature as that of the cellophane tape produced by the composition of the present invention, the adhesiveness is remarkably reduced at low temperature.
At 0 ° C and -5 ° C, there is almost no stickiness and peeling occurs due to the interfacial fracture phenomenon. There is no stickiness at -10 ℃. It also has low deployment power at low temperatures, making it difficult to use. The polyester insulating tape produced by using the composition of the present invention is excellent in low-temperature adhesiveness, electrical characteristics and practical winding workability at -10 ° C. At low temperature, tackiness is improved compared to normal temperature.
The conventional polyester insulating tape using acrylic adhesive has excellent adhesiveness at room temperature and electrical characteristics, but its adhesiveness at low temperature is extremely low. Because it lacks low-temperature adhesiveness,
Practical winding work at -10 ℃ is also difficult. If this tape is subjected to accelerated aging, low-temperature adhesion is improved, but
It is not sufficient as compared with the tape made of the composition of the present invention.
The new-type poultice prepared by using the composition of the present invention is excellent in adhesiveness, sticking property and peeling property, and has no skin irritation. Conventional new-type poultices made mainly of styrene-butadiene-styrene (SBS type) teleblock copolymer and styrene-isoprene-styrene (SIS type) teleblock copolymer have low tackiness. Although it does not cause skin irritation due to application, it peels off during application.

(Advantages of the Invention) Thus, the pressure-sensitive adhesive composition of the present invention contains the butadiene polymer mainly containing 1,4-cis bond, the polyisoprene rubber and / or the polyisobutylene rubber, and the pressure-sensitive adhesive resin in a specific ratio. However, since the glass transition point is -70 ° C or lower, it has excellent low temperature adhesion. The balun of tackiness and cohesion is also good. Since this composition has little temperature dependence of tackiness and cohesive force, it has a good balance between tackiness and cohesive force not only at low temperature but also at high temperature. Some compositions have improved tackiness at low temperatures. Even if an adhesive tape, an adhesive sheet, or a medical patch is prepared using this composition and is applied to the skin, it does not exfoliate for a long time after application because of its excellent adhesiveness. It also has no skin irritation such as redness on the sticking surface. Since it has a certain cohesive force, the adhesive composition remains on the pasting surface during peeling (adhesive residue phenomenon)
Nothing. When the pressure-sensitive adhesive tape is rolled, it has an appropriate degree of adhesiveness, which facilitates the winding operation and the rewinding operation.

The pressure-sensitive adhesive composition of the present invention is also excellent in electric insulation.
Moreover, since the organic solvent has good solubility, the adhesive layer can be formed by using a small amount of the solvent. as a result,
The price can be reduced. The danger of work due to the use of solvents is also avoided.

From the above, the pressure-sensitive adhesive composition of the present invention is useful as a pressure-sensitive adhesive tape, pressure-sensitive adhesive sheet or medical patch, for example, surgical pressure-sensitive drape, pressure-sensitive adhesive dressing, adhesive plaster; cellophane tape, acetate tape. Stationery, light packaging tape; adhesive sheet; adhesive label; electrical insulation vinyl tape; anticorrosion vinyl tape; packaging vinyl tape; polyester insulation tape; Teflon tape; glass cloth tape; acetate cloth tape;
It can be effectively used for polyimide film tape; silicon tape; new type poultice.

Claims (7)

(57) [Claims] 1. A pressure-sensitive adhesive composition containing a butadiene polymer having a 1,4-cis bond content of 90% or more, polyisoprene rubber and / or polyisobutylene rubber, and a pressure-sensitive adhesive resin. Polyisoprene rubber and / or polyisobutylene rubber is contained in the range of 20 to 120 parts by weight with respect to 100 parts by weight of butadiene polymer having a bond of 90% or more, and the butadiene polymer and the polyisoprene rubber and / or Obtained by applying and drying an organic solvent solution of an adhesive composition containing an adhesive resin in the range of 20 to 120 parts by weight with respect to 100 parts by weight of the polyisobutylene rubber, and having a glass transition point of -70 ° C or lower. An adhesive composition. 2. The glass transition point of the butadiene polymer is −
The pressure-sensitive adhesive composition according to claim 1, which has a temperature of 95 ° C or lower. 3. The pressure-sensitive adhesive composition according to claim 1, wherein the softening temperature of the pressure-sensitive adhesive resin is 150 ° C. or lower. 4. The rosin resin such as rosin, polymerized rosin, rosin-glycerin ester, rosin-pentaerythritol ester and hydrogenated products thereof; β-pinene polymer, α-pinene polymer, modified Terpene-based resins such as pinene polymers and mixed pinene polymers; terpene-modified phenolic resins; aliphatic petroleum resins, alicyclic petroleum resins, aromatic petroleum resins having unsaturated bonds from C _{5 to} C ₉ petroleum fractions; The adhesive composition according to claim 1, which is at least one of coumarone resin; coumarone-indene resin and xylene resin. 5. The butadiene polymer has an average molecular weight of 3000.
The pressure-sensitive adhesive composition according to claim 1, which is in the range of 100 to 100,000. 6. The pressure-sensitive adhesive composition according to claim 1, wherein the polyisoprene rubber is natural rubber and / or synthetic cis-1,4-polyisoprene rubber. 7. The pressure-sensitive adhesive composition according to claim 6, wherein the synthetic cis-1,4-polyisoprene rubber has an average molecular weight of 100,000 to 5,000,000.