JP4361551B2 - Adhesive sheet - Google Patents

Description

  The present invention relates to a pressure-sensitive adhesive sheet, and particularly relates to a pressure-sensitive adhesive sheet suitable as a medical pressure-sensitive adhesive tape or sheet to be affixed to the skin such as a bandage, a pressure-sensitive adhesive bandage, and a haptic agent.

  A medical pressure-sensitive adhesive sheet is directly affixed to a person's skin and continues to affix for several minutes to several days depending on the purpose of use. In this pasted state, if the pressure-sensitive adhesive sheet is poor in air permeability or moisture permeability, the natural sweating from the skin is inhibited, and the skin surface on which the pressure-sensitive adhesive sheet is stuck may become stuffy and cause skin irritation. Therefore, in order to prevent such stuffiness, a medical pressure-sensitive adhesive sheet has been proposed in which an adhesive is provided on the entire surface of an air-impermeable support and the sheet is then perforated. The air permeability is insufficient and is not always satisfactory.

  On the other hand, as another countermeasure against stuffiness, a material having air permeability and moisture permeability such as a woven fabric, a knitted fabric, a nonwoven fabric, a porous urethane film, or various organic polymer films subjected to perforation treatment is used, and There has also been proposed a medical pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive is not provided on one or both surfaces of a support but is partially provided so as to ensure a gas flow path such as a stripe shape, a dot shape, or a lattice shape. Although air permeability is solved with this pressure-sensitive adhesive sheet, when water is applied to the pressure-sensitive adhesive sheet from the outside, water penetrates through the support, or the air passage between the pressure-sensitive adhesive layers has a favorable water intrusion path. In many cases, water enters the pressure-sensitive adhesive sheet thus stuck to block the air passage, and on the contrary, promotes sticking steaming.

  In view of the above-described problems in conventional pressure-sensitive adhesive sheets, an object of the present invention is to provide a pressure-sensitive adhesive sheet that is excellent in air permeability or moisture permeability and also excellent in waterproofness.

The present invention has the following features.
(1) A plurality of strips of pressure-sensitive adhesive layers 2 are provided on at least one surface of a support 1 having air permeability, moisture permeability, and waterproofness.
The inter-strip space 3 existing between the pressure-sensitive adhesive layers adjacent to each other is also wavy by being present between the pressure-sensitive adhesive layers 2 of the wavy line,
The thickness of the pressure-sensitive adhesive layer 2 is 10 to 100 μm, the width of each wavy line of the pressure-sensitive adhesive layer 2 is 0.5 to 10 mm, the width of the space 3 is 1 to 3 mm, and
Defined width strip between the space 3 and by the product of the thickness of the pressure-sensitive adhesive layer 2, the sectional area of each strip between the space 3 is ^{1 × 10 -4 cm 2 ~1 ×} 10 -3 cm 2 become as in, wherein the width of the strip between the space 3 and the thickness of the pressure-sensitive adhesive layer 2 is selected, the pressure-sensitive adhesive sheet.
(2) The pressure-sensitive adhesive sheet according to (1), wherein the pressure-sensitive adhesive layer 2 extends to both ends of the support 1.
(3) The pressure-sensitive adhesive sheet according to (1) or (2), which is for medical use.
(4) The support 1 having air permeability, moisture permeability, and waterproofing is a porous sheet made of a material that has a large water contact angle and is difficult to wet with water, or a porous sheet made of a material that easily gets wet with water. The pressure-sensitive adhesive sheet according to any one of (1) to (3), wherein the pressure-sensitive adhesive sheet is a sheet formed by water repellent treatment.
(5) The pressure-sensitive adhesive sheet according to the above (4), wherein the porous sheet made of a material that easily wets water is a kind selected from a woven fabric, a knitted fabric, a nonwoven fabric, paper, and a perforated film of polyvinyl alcohol.

The pressure-sensitive adhesive layer is not provided on the entire surface of one side or both sides of the support, but is provided in a strip shape on one or both sides, so that the space between the strips functions well as an air passage. In addition, since the support has a breathability or moisture permeability and is waterproof, the space cross-sectional area between the above stripes is a small cross-sectional area of 2 × 10 ⁻³ cm ² or less. Intrusion of water into the gap is prevented. As a result, the above-described problems can be solved by the present invention. (2) Each of the following inventions of the present invention is a preferred embodiment of the present invention, and the operation and effect of each will be clarified by the following description.

  As the support, one that is breathable or moisture permeable and waterproof is used. In general, a porous sheet made of a material that has a large contact angle with water and hardly wets with water, or a porous sheet made of a material that easily gets wet with water, but with water-repellent treatment, is exemplified. Examples of porous sheets made of materials that are difficult to wet with water include polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polyurethane, and polyester. Examples thereof include perforated films made of organic polymers such as other plastics such as polyamide, foamed sheets having open cells, woven fabrics, knitted fabrics, non-woven fabrics, and papers. Examples of the porous sheet made of a material that easily wets water include woven fabrics, knitted fabrics, nonwoven fabrics, paper, and polyvinyl alcohol perforated films made of organic polymers such as cotton, cellulose, and polyvinyl alcohol. A porous sheet made of a material that easily wets water is used after being subjected to water repellent treatment with a known water repellent. In addition, the porous sheet of the material which does not easily get wet with water is used after being subjected to water repellent treatment as necessary. The support may be non-stretchable, or may be stretchable in the vertical direction and / or the horizontal direction.

  As the pressure-sensitive adhesive, various types known or practically used in the field of medical pressure-sensitive adhesive sheets can be used in the present invention. In particular, acrylic adhesives and rubber adhesives with less skin irritation are preferred.

  In the present invention, the pressure-sensitive adhesive is provided in a plurality of strips on one or both sides of the above-described support, and a space functioning as an air passage is provided between the strips. Hereinafter, this space will be referred to as a streak space. The thickness of the strip-like pressure-sensitive adhesive layer may be appropriately determined depending on the properties of the pressure-sensitive adhesive used and the purpose of use of the pressure-sensitive adhesive sheet of the present invention, but is generally about 5 to 200 μm, particularly about 10 to 100 μm. Is preferred. On the other hand, the width of the pressure-sensitive adhesive layer is about 0.5 to 10 mm.

  The pressure-sensitive adhesive layer may be linear, corrugated, or other shape as long as the interstitial space can be secured. However, in general, a wavy line with a small change with time in the cross-sectional area of the space between lines is particularly preferable. The shape of the wavy line may be a waveform that rises and falls symmetrically with respect to the base line, such as a sine curve, pseudo sine curve, triangular wave, or arc wave, or an arc, triangle, ellipse, or other shape on only one side of the base line. It may be a waveform that surfs in the form. Regardless of the waveform, the waveform width and wave period can be appropriately set according to the purpose of use of the present invention.

The interstitial space has a space cross-sectional area of about 2 × 10 ⁻³ cm ² or less, particularly about 1 × 10 ⁻³ cm ² or less. However, if the cross-sectional area is too small, the air permeability based on the presence of the interstitial space of the pressure-sensitive adhesive sheet is lowered, so that it is preferably about 1 × 10 ⁻⁴ cm ² or more. By using the above-mentioned waterproof support and making the interstitial space a small cross-sectional area, water can be effectively prevented from entering the interstitial space based on the surface tension of water and the high viscous flow resistance. be able to.

  As long as the above-described space cross-sectional area is within a range that can be ensured, the inter-spaces may have various cross-sectional shapes. For example, a square, a wide rectangle, a deep groove rectangle, a trapezoid and the like are exemplified. When the thickness of the pressure-sensitive adhesive is about 10 to 100 μm as described above, the width of the inter-strip space, that is, the distance between two adjacent pressure-sensitive adhesive layers is suitably about 1 to 3 mm.

  The pressure-sensitive adhesive layer can be formed on one side or both sides of the support by various methods well known in the art. Note that the pressure-sensitive adhesive layer may be formed only at a necessary location on the support, but if the pressure-sensitive adhesive layer is not present at the end of the support, it will be formed at the end of the support during use of the pressure-sensitive adhesive sheet of the present invention. Fraying may occur and easily peel from the skin. In such a case, the fraying can be prevented and the problem of peeling from the skin can be improved by forming the pressure-sensitive adhesive layer even at the end of the support.

Regarding the production of the pressure-sensitive adhesive sheet of the present invention, the shape of the pressure-sensitive adhesive layer is pre-patterned, and the pressure-sensitive adhesive layer pattern is screen-printed on almost the entire surface on one side or both sides of the continuously running support, computer control It is preferable that the film is continuously formed by drawing by the above method, combing method described later, or other methods.
In the above combing method, the pressure-sensitive adhesive paint is applied to substantially the entire surface of the temporary base sheet continuously running at a constant line speed, and then fixed in a direction perpendicular to the traveling direction of the temporary base sheet. After removing a part of the pressure-sensitive adhesive paint layer applied with a comb having a number of scratches reciprocating at a speed and finally drying the wavy pressure-sensitive adhesive paint layer remaining on the temporary substrate sheet The pressure-sensitive adhesive layer is transferred to the support sheet. According to this method, various corrugated pressure-sensitive adhesive layers can be formed by adjusting the line speed of the temporary base sheet, the reciprocating speed of the comb, the reciprocating motion itself, the number of comb scrapes, etc. it can. When using a support sheet that allows combing of the pressure-sensitive adhesive paint layer before drying, a support sheet may be used instead of the temporary base sheet described above. In that case, the transfer step can be omitted.
The support of the pressure-sensitive adhesive sheet piece cut into a desired shape and size from the long sheet manufactured by the above method has the pressure-sensitive adhesive layer substantially spread over substantially the entire surface including its end. Therefore, there is no fraying problem as described above.

Hereinafter, the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a partial plan view of an embodiment of the present invention, and FIG. 2 is a partially enlarged sectional view taken along line XX in FIG. 1 and 2, 1 is a support, 2 is a sine-curved pressure-sensitive adhesive layer, and 3 is an interstitial space formed between the pressure-sensitive adhesive layers 2 and 2. Since the interstitial space 3 also exists between the pressure-sensitive adhesive layers 2 and 2, it has a sine curve shape, and its cross-sectional area, that is, the product of the width W of the inter-spaces 3 and the thickness T of the pressure-sensitive adhesive layer 2 is It has the size described above.

Comparative Example 1
Using a release paper having a silicone treatment on one side as a temporary base sheet, 10 parts by weight of 2-hydroxyethyl acrylate and 90 parts by weight of 2-ethylhexyl acrylate are copolymerized on the silicone-treated surface of the release paper The resulting acrylic acid-based pressure-sensitive adhesive solution is applied to the entire surface without providing any interstitial spaces, then dried, and finally the pressure-sensitive adhesive layer on the release paper is composed of a 25 μm thick porous polyurethane film (manufactured by Okura Kogyo Co., Ltd.). It moved on the support body and obtained the 50-micrometer-thick adhesive sheet of the adhesive layer in this way.

Example 1
Using a release paper with one side treated with silicone as a temporary base sheet, 10 parts by weight of 2-hydroxyethyl acrylate and 90 parts by weight of 2-ethylhexyl acrylate on the silicone-treated side of the release paper by the combing method described above 1 is used to form a large number of sine curve-shaped strips as shown in FIG. 1, and then dried to finally form a pressure-sensitive adhesive layer on the release paper with a thickness of 25 μm. On a support made of a porous polyurethane film (manufactured by Okura Kogyo Co., Ltd.). An adhesive sheet having 5 × 10 ⁻³ cm ² , a sine curve period of 100 mm, and a sine curve amplitude of 50 mm was obtained.

Example 2
A pressure-sensitive adhesive sheet different from Example 1 was obtained only in that the width of the interstitial space was 3 mm and the cross-sectional area of the interstitial space was 1.5 × 10 ⁻³ cm ² .

Comparative Example 2
A pressure-sensitive adhesive sheet different from Example 1 was obtained only in that the width of the interstitial space was 5 mm and the cross-sectional area of the interstitial space was 2.5 × 10 ⁻³ cm ² .

Comparative Example 3
A pressure-sensitive adhesive sheet different from Comparative Example 1 was obtained only in that the thickness of the pressure-sensitive adhesive layer was 100 μm.

Example 3
A pressure-sensitive adhesive sheet different from Example 1 was obtained only in that the thickness of the pressure-sensitive adhesive layer was 100 μm and the cross-sectional area of the interstitial space was 1.0 × 10 ⁻³ cm ² .

Comparative Example 4
A pressure-sensitive adhesive sheet different from Example 2 was obtained only in that the thickness of the pressure-sensitive adhesive layer was 100 μm and the cross-sectional area of the interstitial space was 3.0 × 10 ⁻³ cm ² .

Comparative Example 5
A pressure-sensitive adhesive sheet different from Comparative Example 2 was obtained only in that the thickness of the pressure-sensitive adhesive layer was 100 μm and the cross-sectional area of the interstitial space was 5.0 × 10 ⁻³ cm ² .

  Each pressure-sensitive adhesive sheet of Examples 1 to 3 and Comparative Examples 1 to 5 was stored at 60 ° C. for 1 day, and then subjected to the following test.

Test method for moisture permeability: 10 cc of distilled water was collected in a weighing bottle with an inner diameter of 38 mm and a height of 40 mm, and a 4 × 4 cm square adhesive sheet piece was attached to the mouth of the weighing bottle with the adhesive layer facing down. It was put into a constant temperature and humidity chamber set at a temperature of 40 ° C. and a relative humidity of 30% and left for 24 hours. The moisture permeability (g / m ² , 24 hours) was calculated by the following formula from the difference in weight before and after being left for 24 hours in a constant temperature and humidity chamber of the weighing bottle with the adhesive sheet piece attached. The weight was measured with a direct balance (minimum scale: 1/1000 g).
Moisture permeability = (weight before leaving-weight after standing) x 882.192

  Test method for simmerability: A 2 × 1 cm square absorbent pad was placed at the center of a 4 × 3 cm square pressure sensitive adhesive sheet piece, which was affixed to the skin and immersed in warm water at 40 ° C. for 30 minutes. Subsequently, the adhesive sheet piece was peeled off from the skin, and at that time, it was examined whether or not the skin at the applied site was moistened white.

  Waterproof test method: A 2 × 1 cm square absorbent pad was placed at the center of a 4 × 3 cm square pressure sensitive adhesive sheet piece, which was affixed to the skin and immersed in warm water at 40 ° C. for 30 minutes. Subsequently, the adhesive sheet piece was peeled from the skin, and the presence or absence of water intrusion into the absorption pad was examined. When water intrusion was not recognized, it was accepted, and when it was recognized, it was rejected.

  The above measurement results are shown in Table 1. As is clear from the table, each of the pressure-sensitive adhesive sheet pieces of Examples 1 to 3 showed excellent results in any test of moisture permeability, simmerability, and waterproofness. On the other hand, Comparative Example 1 and Comparative Example 3 having no interstitial space are excellent in waterproofness but have problems in moisture permeability and suffocation. On the other hand, Comparative Example 2, Comparative Example 4 and Comparative Example 5, which have interstitial spaces but have an excessive cross-sectional area, have a problem in waterproofness even though they have good moisture permeability and stuffiness.

  Since the pressure-sensitive adhesive sheet of the present invention is excellent in air permeability or moisture permeability, natural sweating is performed well even when applied for a long time, and the problem of stuffiness and skin irritation based on stuffiness is reduced. Moreover, since it is excellent in waterproofness, it becomes possible to wash, shower or take a bath with the adhesive sheet still attached. Further, fraying of the edge of the support and peeling phenomenon during use can be reduced or prevented. Therefore, the pressure-sensitive adhesive sheet of the present invention is suitable as a medical pressure-sensitive adhesive tape or sheet to be applied to the skin, such as a bandage, a pressure-sensitive adhesive bandage, and a haptic agent.

It is a partial top view of the Example of this invention. FIG. 2 is a partial enlarged cross-sectional view taken along line XX in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support body 2 Adhesive layer 3 Interstitial space formed between adhesive layers

Claims (5)

A plurality of strips of pressure-sensitive adhesive layers (2) are provided on at least one side of the support (1) that is breathable or moisture permeable and waterproof,
The interstrip space (3) existing between the adhesive layers adjacent to each other is also wavy by being present between the adhesive layers (2) of the wavy strip,
The thickness of the pressure-sensitive adhesive layer (2) is 10 to 100 μm, the width of each wavy line of the pressure-sensitive adhesive layer (2) is 0.5 to 10 mm, and the width of the space (3) is 1 to 3 mm. Yes, and
Each cross-sectional area (3) defined by the product of the width of the inter-space (3) and the thickness of the adhesive layer (2) is 1 × 10 ⁻⁴ cm ² to 1 × 10 ^{−. The} pressure-sensitive adhesive sheet , wherein the width of the inter-space (3) and the thickness of the pressure-sensitive adhesive layer (2) are selected so as to be ³ cm ² .   The pressure-sensitive adhesive sheet according to claim 1, wherein the pressure-sensitive adhesive layer (2) extends to both ends of the support (1).   The pressure-sensitive adhesive sheet according to claim 1 or 2, which is for medical use. The air-permeable or moisture-permeable and waterproof support (1) is a porous sheet made of a material that has a large water contact angle and is difficult to wet with water, or a porous sheet made of a material that easily gets wet with water. The pressure-sensitive adhesive sheet according to any one of claims 1 to 3, which is a sheet obtained by water treatment. The pressure-sensitive adhesive sheet according to claim 4, wherein the porous sheet made of a material that easily wets water is a kind selected from a woven fabric, a knitted fabric, a nonwoven fabric, paper, and a perforated film of polyvinyl alcohol.

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