JP2006055411A - Rubber adhesive composition to be stuck to skin, and adhesive tape or sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a rubber adhesive composition, excellent in the stability of the characteristics against aging and in the balance between water vapor permeability and adhesive characteristics, and especially, excellently usable for an adhesive tape or sheet to be stuck to the skin. <P>SOLUTION: This rubber adhesive composition to be stuck to the skin is characterized by a functional group modified liquid rubber component D blended in an elastomer component A made of natural rubber and/or diene synthetic rubber, an adhesiveness applying resin B and a rubber adhesive C made of a hydrophilic polymeric component at the rate of 10-40% in weight based on the elastomer component A. The rubber adhesive composition is applied to an elastic base material to prepare the adhesive tape or sheet. The adhesive composition to be stuck to the skin is excellent in the stability of the characteristics against aging, and in the balance between the water vapor permeability and the adhesive characteristics. Furthermore, the adhesive composition can keep the stimulus to the skin low. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape or sheet using the same, and more specifically, a rubber for skin application used for external use in the medical / hygiene field, sports field, beauty / health field, etc. The present invention relates to an adhesive composition and an adhesive tape or sheet.

  In general, rubber-based pressure-sensitive adhesives are excellent in adhesiveness and relatively easy to adjust the pressure-sensitive adhesive properties, and thus have been used for a long time in pressure-sensitive adhesive tapes and sheets for medical applications, sports fields, and beauty and health applications. In particular, for use in living organisms, it is used in a number of product forms because of its excellent balance between good initial adhesiveness to the skin and peeling properties when peeled off. By the way, the adhesiveness to the skin varies depending on individual differences and the site of use, and it is necessary to maintain good adhesiveness even in the state of sweating during bathing and sports. The required properties are becoming increasingly demanding. Moreover, in the adhesion | attachment to skin, the thing with lower irritation is calculated | required, and various attempts are made to the adhesive in order to improve irritation to skin.

  To improve skin irritation, reduce the physical modulus of the skin by reducing the elastic modulus of the adhesive, remove the chemical irritation factor of the adhesive, and remove the chemical irritation The physiological irritation is removed by reducing the moisture permeability and increasing the moisture permeability to reduce the amount of water retained on the skin surface. Above all, rubber adhesives use hydrophobic rubber or tackifying resin as a base material, so the moisture permeability is low, which causes physiological irritation due to moisture retention on the skin surface during use. It is likely to occur and is considered to be the main cause of skin rash and skin peeling.

  One means for solving the low moisture permeability of the rubber-based pressure-sensitive adhesive is to provide pores in the pressure-sensitive adhesive tape or sheet to improve the blocking property. However, the portions other than the pores are still in a sealed state, which does not lead to a fundamental solution.

Also known is a method for improving moisture permeability by adding a water-soluble or water-swellable polymer compound such as polyvinyl alcohol, methylcellulose, or hydroxyethylcellulose to the rubber-based pressure-sensitive adhesive (see, for example, Patent Document 1). . In this method, by including a water-soluble or water-swellable polymer compound, the rubber-based pressure-sensitive adhesive can achieve a water-dispersed open state when the pressure-sensitive adhesive tape or sheet is applied, thereby allowing the skin and the pressure-sensitive adhesive to be separated from each other. It is possible to reduce the amount of water stored during the period. However, these water-soluble or water-swellable polymer compounds have poor compatibility with hydrophobic rubber-based pressure-sensitive adhesives, so a uniform dispersion cannot be obtained, and it is difficult to adjust and homogenize the properties. There is also a problem that the hydrophilic component bleeds on the surface of the pressure-sensitive adhesive when left for a long period of time and causes a decrease in the pressure-sensitive adhesive performance.
Japanese Patent Publication No.58-174484

  The present invention aims to solve the above-mentioned problems. More specifically, the present invention is excellent in the stability of characteristics over time and the balance between moisture permeability and adhesive properties, and can be preferably used particularly for adhesive tapes and adhesive sheets for skin application. The object is to provide a rubber-based pressure-sensitive adhesive composition.

  As a result of earnest research on the above problems, the rubber adhesive containing the main component of the adhesive that is hydrophobic and the hydrophilic component that imparts moisture permeability is conventionally because of its strong skin irritation. By adding functional group-modified liquid rubber that has been repelled, it improves the compatibility between the hydrophobic adhesive component and the hydrophilic component, provides stable moisture permeability, and also reduces irritation to the skin. It was found that the pressure-sensitive adhesive composition was excellent in balance with pressure-sensitive adhesive properties. Moreover, it confirmed that these adhesive compositions became an adhesive tape and sheet | seat for skin sticking which has a preferable characteristic by apply | coating to an elastic base material, and completed this invention based on these knowledge.

Therefore, the present invention
(A) an elastomer component comprising natural rubber and / or diene synthetic rubber;
(B) a tackifier resin, and (C) a rubber-based adhesive composed of a hydrophilic polymer component,
(D) It is related with the rubber adhesive composition for skin sticking characterized by mix | blending a functional group modified | denatured liquid rubber component at 10 to 40 weight% based on this elastomer component.

A preferred embodiment of the present invention is:
(D) The rubber-based pressure-sensitive adhesive composition for skin application, characterized by containing a liquid rubber modified with a carboxyl group or a hydroxyl group as at least a part of the functional group-modified liquid rubber component;
Further, (E) the rubber-based adhesive composition for skin application characterized by containing an anti-aging agent, and the moisture permeability under the conditions of 40 ° C. and 90% RH is 300 g / m ² · 24 h or more. This is a rubber adhesive for skin application.

The present invention also provides
The present invention relates to an adhesive tape or sheet obtained by applying the rubber adhesive composition for skin application to a stretchable substrate.

  The rubber-based pressure-sensitive adhesive composition for skin application of the present invention is excellent in stability of characteristics over time and excellent in balance between moisture permeability and pressure-sensitive adhesive characteristics. In addition, the skin irritation can be kept low. The adhesive tape and sheet coated with the rubber adhesive composition for skin application can be expected to be used for external applications such as medical / hygiene field, sports field, and beauty / health field of emergency adhesive plaster and dressing material.

  The elastomer component used in the present invention includes natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), styrene / butadiene block copolymer (SBS), and hydrogenated rubber thereof. (SEBS), styrene / isoprene block copolymer (SIS) and its hydrogenated rubber (SEPS), polyisobutylene (PIB), butyl rubber (IIR) and the like, and one or a combination of these can be used.

The tackifying resin used in the present invention is a hydrophobic resin that is compatible with a hydrophobic elastomer component serving as a base and develops tackiness. Specifically, a rosin resin, a rosin ester resin, a terpene resin, Examples include terpene phenol resins, C5 petroleum resins, C5 / C9 petroleum resins, DCPD petroleum resins, coumarone-indene resins, and the like.

  The hydrophilic polymer component used in the present invention imparts moisture permeability to the rubber-based pressure-sensitive adhesive, and includes polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polycarboxymethyl cellulose (CMC), polyethylene glycol (PEG), Synthetic polymers such as polypropylene glycol (PPG), polyglycerin, polyacrylate, polyethylene oxide (PEO), polyvinyl butyral, polyoxyethylene nonylphenyl ether, carrageenan, locust bean gum, tamarind gum, guar gum, xanthan gum, gellan gum, tara gum , Natural polysaccharides such as gum arabic, karaya gum and pectin, proteins such as gelatin and albumin, natural high molecular substances such as starch and agar, other methyl vinyl ether, Cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, sodium polyacrylate, sodium polystyrene sulfonate, polyethylene imine, dextran, dextran sulfate, magnesium aluminum silicate, synthetic hectorite, aluminum sulfate, etc. It is not something. In the rubber-based pressure-sensitive adhesive composition for skin application of the present invention, these hydrophilic polymers are used alone or in combination.

  The rubber-based pressure-sensitive adhesive composition for skin patch of the present invention is based on the rubber-based pressure-sensitive adhesive composed of the above three components, that is, an elastomer component, a tackifier resin, and a hydrophilic polymer component. It is obtained by adding a functional group-modified liquid rubber component in an amount of% by weight. This functional group-containing liquid rubber component is a material that has conventionally been avoided due to its strong skin irritation, but in the present invention, a hydrophobic elastomer component, a hydrophilic hydrophilic polymer component, and a functional group are used. By forming a uniform mixed system with the modified liquid rubber component, skin irritation is not observed but rather improved.

  Examples of the functional group-modified liquid rubber component used in the present invention include a liquid rubber whose side chain is modified with a carboxyl group or a hydroxyl group. Examples of the liquid rubber whose side chain is modified with a carboxyl group include liquid isoprene rubber (LIR) and liquid polybutadiene rubber (LPB). Specifically, LIR-403 (manufactured by Kuraray Co., Ltd., molecular weight 25000), LIR-410 (Manufactured by Kuraray Co., Ltd., molecular weight 25000), LPB-M1000-20 (manufactured by Nippon Petrochemical Co., Ltd., molecular weight 1000), LPB-M2000-20 (manufactured by Nippon Petrochemical Co., Ltd., molecular weight 2000) and the like. Specific examples of the liquid rubber whose side chain is modified with a hydroxyl group include LIR-506 (manufactured by Kuraray Co., Ltd., molecular weight 25000), LIR-510 (manufactured by Kuraray Co., Ltd., molecular weight 25000) and the like.

  The addition amount of the functional group-containing liquid rubber component used in the present invention is 10 to 40% by weight with respect to the elastomer component. If it is 10% by weight or less, the effect of improving the compatibility with the hydrophilic component is not sufficiently exhibited. If it is 40% by weight or more, the cohesive force of the pressure-sensitive adhesive is insufficient, and good adhesiveness cannot be obtained. Furthermore, in the present invention, liquid elastomer components such as non-functional LIR, LPB, polyisobutylene and polybutene may be appropriately mixed and used.

  In addition, in the rubber adhesive composition for skin application of the present invention, anti-aging agents such as bisphenol, hindered amine, and benzimidazole used in general rubber adhesives, UV absorbers, light stabilizers, etc. Can be suitably added in combination of one or more. Further, as other fillers, calcium carbonate, zinc white, titanium oxide, calcium hydroxide, aluminum hydroxide, aluminum sulfate, talc, clay and the like may be blended as needed.

The moisture permeability of the rubber adhesive composition for skin application of the present invention is preferably such that each component is blended so that the moisture permeability under the conditions of 40 ° C. and 90% RH is 300 g / m ² · 24 h or more. . The rubber-based pressure-sensitive adhesive composition having a moisture permeability within this range has extremely low irritation to the skin, and does not cause skin fogging or peeling due to water retention during application.

  The pressure-sensitive adhesive tape or sheet of the present invention can be obtained by applying an appropriate amount of the rubber-based pressure-sensitive adhesive composition for skin application of the present invention thus prepared to a stretchable substrate. The stretchable substrate is not particularly limited as long as it has an appropriate strength and air permeability, and for example, paper, cloth, nonwoven fabric, a plastic film having fine holes, and the like can be used.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not intending to be limited to these.

Examples 1-5 and Comparative Examples 1-4
Elastomer component, tackifier resin, hydrophilic polymer component, and functional group-modified liquid rubber component are blended as shown in Table 1 below, and non-functional liquid rubber, zinc white and anti-aging agent are added as additives. And the rubber-type adhesive composition for skin sticking of Examples 1-5 according to this invention was prepared.
Further, it contains a hydrophilic polymer component and a liquid rubber component, but the liquid rubber component is non-functional (Comparative Example 1), contains a functional group-modified liquid rubber component but does not contain a hydrophilic polymer component ( Comparative Example 2), rubber-based pressure-sensitive adhesive compositions containing only a non-functional liquid rubber component (Comparative Example 3), and those containing neither a hydrophilic polymer component nor a liquid rubber component (Comparative Example 4) Prepared for comparative purposes.
The pressure-sensitive adhesive sheets were prepared by applying the rubber-based pressure-sensitive adhesive compositions of Examples 1 to 5 and Comparative Examples 1 to 4 thus prepared on a knitted fabric to 100 g / m ² . And this adhesive sheet is (1) moisture permeability, (2) 23 ° C. bakelite adhesive strength, (3) glass plate holding power, (4) skin sticking test, (5) adhesive remaining after peeling, (6) Re-stickability to skin, and (7) Presence / absence of erythema after peeling of skin were evaluated according to the following methods.
The results are shown in Table 1.

［式中、Ｓは透湿面積（ｃｍ²）を、Ｗは１時間当たりの質量増加（ｇ／ｈｒ）を表す。］
（２）２３℃対ベークライト粘着力
ＪＩＳ Ｚ−０２３７に従い、２３℃雰囲気下でベークライトパネルに２４ｍｍ幅の試料を貼付し、２ｋｇのゴムロールで３００ｍｍ／分の速度で１往復圧着し、２０分放置後、剥離角度１８０度、剥離速度３００ｍｍ／分の剥離力を測定した。
（３）対ガラス板保持力
作成直後、並びに４０℃、９０％ＲＨ雰囲気下で１ヶ月促進経時した粘着シートの対ガラス板保持力を測定した。なお、４０℃、９０％ＲＨ雰囲気下での１ヶ月促進経時はなりゆき雰囲気下で約６ヶ月経時に相当する。
対ガラス板保持力の測定はＪＩＳ Ｚ−０２３７に従い、２３℃雰囲気下で幅２４ｍｍの試料をガラス板に２４ｍｍ×２５ｍｍの面積となるように貼付し、２ｋｇのゴムロールで３００ｍｍ／分の速度で１往復圧着した。２０分放置後、粘着シートが垂直に垂れ下がるように吊るし、１ｋｇの荷重を加えて、１５分後のズレ長さを測定した。
（４）皮膚貼付性試験
１５ｍｍ幅の試料を上腕部内側に貼付し、２４時間後の貼付性を評価した。
○：剥がれなし △：一部剥がれ ×：全面剥がれ
（５）対皮膚剥離後粘着剤残留
皮膚貼付性試験後の粘着剤の残留性を評価した。
○：残留なし △：一部残留 ×：全面残留
（６）対皮膚再貼付性
皮膚貼付性試験後の試料を再度、皮膚に貼付した場合の貼付性を評価した。再貼付性が低下すると、粘着面に皮膚の角質が移行し、皮膚への刺激性が高くなる。
○：再貼付可 △：粘着性やや低下も可 ×：粘着性なく不可
（７）対皮膚剥離後の紅斑の有無
皮膚貼付性試験後の紅斑の有無を評価した（被検査数１０人）。
−：紅斑なし ±：僅かに紅斑あり ＋：紅斑を認める (1) Moisture permeability Moisture permeability was evaluated as the amount of water vapor that passes through the test material of a unit area in a certain time. Specifically, in a 40 ° C. atmosphere, when the relative humidity of the space on one side separated by the test sample is 90% and the space on the other side is kept dry by the hygroscopic agent, it passes the test sample in 24 hours. The mass (g) of water vapor was measured and converted per 1 m ^{2 of} the test material.
The measurement is performed in accordance with JIS Z-0208. A round sample with a diameter of about 10 mm larger than the inner diameter of the cup is placed on a cup containing about 16 g of calcium chloride hygroscopic agent, and a rubber packing and ring are put on the cup to prevent the sample from shifting. Stopped. After measuring the total mass of this specimen, it was placed in a constant temperature and humidity chamber under a 40 ° C., 90% RH atmosphere, the mass change for each fixed time was measured, and the moisture permeability was determined according to the following formula:

[In the formula, S represents a moisture permeable area (cm ² ), and W represents an increase in mass per hour (g / hr). ]
(2) Adhesive strength against bakelite at 23 ° C. According to JIS Z-0237, a sample with a width of 24 mm was pasted on a bakelite panel in an atmosphere at 23 ° C., followed by one reciprocal bonding at a speed of 300 mm / min with a 2 kg rubber roll, and left for 20 minutes. The peeling force was measured at a peeling angle of 180 degrees and a peeling speed of 300 mm / min.
(3) Holding power against glass plate Immediately after creation, the holding power against the glass plate of the pressure-sensitive adhesive sheet that had been accelerated for one month in an atmosphere of 40 ° C. and 90% RH was measured. Note that the accelerated aging for one month in a 40 ° C., 90% RH atmosphere corresponds to the aging for about six months in a changing atmosphere.
The measurement of the holding power against the glass plate is in accordance with JIS Z-0237, a sample having a width of 24 mm is attached to a glass plate in an atmosphere of 23 ° C. so as to have an area of 24 mm × 25 mm, and 1 kg at a speed of 300 mm / min with a 2 kg rubber roll. Reciprocating. After leaving for 20 minutes, the adhesive sheet was hung so as to hang vertically, a load of 1 kg was applied, and the shift length after 15 minutes was measured.
(4) Skin sticking test A 15 mm wide sample was stuck to the inner side of the upper arm, and the sticking property after 24 hours was evaluated.
○: No peeling Δ: Partial peeling ×: Full peeling (5) Adhesive residue after skin peeling The adhesive residue after the skin sticking test was evaluated.
○: No residue Δ: Partial residue ×: Residual on the entire surface (6) Resistance to skin re-sticking The stickability when the sample after the skin sticking property test was again attached to the skin was evaluated. When the re-stickability is lowered, the skin keratin is transferred to the adhesive surface, and the skin irritation is increased.
○: Possible to be re-applied Δ: Adhesiveness is also possible to be slightly lowered ×: Impossible without adhesiveness (7) Presence / absence of erythema after peeling of the skin The presence / absence of erythema after skin adhesion test was evaluated (10 subjects tested).
-: No erythema ±: Slight erythema +: Erythema

Elastomer component 1: natural rubber, crepe paste, Mooney viscosity 68
Elastomer component 2: SBR, Nipol 1052 (manufactured by Nippon Zeon Co., Ltd., bound styrene content 23.5%, Mooney viscosity 52)
Elastomer component 3, BR, Nipol BR-1220 (manufactured by Nippon Zeon Co., Ltd., Mooney viscosity 44)
Tackifying resin: Alcon P-100 (Arakawa Chemical Co., Ltd., hydrogenated alicyclic petroleum resin)
Hydrophilic polymer component 1: polyethylene glycol # 600
Hydrophilic polymer component 2: Aqua Coke TWB-P (manufactured by Sumitomo Seika Co., Ltd., polyethylene oxide)
Functional group-modified liquid rubber component 1: LIR-403 (manufactured by Kuraray Co., Ltd., carboxyl group-modified liquid isoprene rubber, molecular weight 25000)
Functional group-modified liquid rubber component 2: LIR-506 (Kuraray Co., Ltd., hydroxyl-modified liquid isoprene rubber, molecular weight 25000)
Non-functional liquid rubber: LIR30 (manufactured by Kuraray Co., Ltd., liquid isoprene rubber, molecular weight 29000)
Zinc flower: Zinc flower No. 1 (Mitsui Metal Mining Co., Ltd.)
Anti-aging agent: Swanox BHT (Seiko Chemical Co., Ltd., 2,6-di-t-butyl-4-methylphenol)

As is clear from the evaluation results shown in Table 1, the rubber-based pressure-sensitive adhesive compositions of Examples 1 to 5 have stability of holding power over time, show stable adhesive properties without bleeding of hydrophilic resin, By adjusting the moisture permeability to a certain range, the skin irritation was improved, and an adhesive sheet with an excellent balance of adhesive properties was obtained.
On the other hand, in Comparative Example 1, since the functional group-modified liquid rubber component was not included, a decrease in the glass plate holding power was observed with the lapse of time, and the bleed resistance of the hydrophilic polymer was inferior.
Further, when the hydrophilic polymer of Comparative Example 2 is not included, and when both the functional group-modified liquid rubber component of Comparative Example 3 and the hydrophilic polymer are not included, moisture permeability is low, and irritation to the skin in the skin adhesion test. Sex was recognized.
Further, in the case where the liquid rubber component and the functional group-modified liquid rubber component of Comparative Example 4 and the hydrophilic polymer are not included, the moisture permeability is low, coupled with the decrease in re-stickability due to high adhesive strength, and thus significant irritation in the skin adhesion test. Sex was recognized.

Claims (5)

(A) an elastomer component comprising natural rubber and / or diene synthetic rubber;
(B) a tackifier resin, and (C) a rubber-based adhesive composed of a hydrophilic polymer component,
(D) A rubber-based adhesive composition for skin application, comprising 10 to 40% by weight of a functional group-modified liquid rubber component based on the elastomer component. (D) The rubber-based pressure-sensitive adhesive composition for skin application according to claim 1, characterized in that liquid rubber modified with a carboxyl group or a hydroxyl group is contained as at least a part of the functional group-modified liquid rubber component. . The rubber-based pressure-sensitive adhesive composition for skin application according to claim 1 or 2, further comprising (E) an anti-aging agent. The rubber adhesive for skin application according to any one of claims 1 to 3, wherein the moisture permeability under conditions of 40 ° C and 90% RH is 300 g / m ² · 24 h or more. Agent composition. A pressure-sensitive adhesive tape or sheet obtained by applying the rubber-based pressure-sensitive adhesive composition for skin application according to claim 1 to a stretchable substrate.