JPS606775A - Moisture-permeable, pressure-sensitive adhesive film - Google Patents

Abstract

PURPOSE:To provide the titled film which has good moisture-peamability and is very flexible and highly stretchable and in which the support and the pressure- sensitive adhesive compsn. do not have any pores, any voids nor discontinuous cross section, by coating a polyurethane support with a pressure-sensitive compsn. mainly composed of polyurethane. CONSTITUTION:A pressure-sensitive adhesive compsn. mainly composed of polyurethane (e.g. one obtd. by forming a film from a soln. of 100pts. urethane rubber 80pts. phenolic resin and 2pts. crosslinking agent dissolved in a solvent, on a release paper and drying it) is contact-bonded to a polyurethane film substrate (e.g. a film of 20-300mu in thickness obtd. by dissolving 100pts. adipate polyester and 50pts. diphenylmethane dissocyanate in a solvent, coating a release paper with the resulting soln. to form a film, drying it and peeling the release paper), thus obtaining the titled film which is flexible and highly stretchable and in which the support and the pressure-sensitive adhesive compsn. do not have any pores, any voids nor discontinous cross section. This tape can be used as a tape for cataplasm and patch as well as a surgical tape for preventing secondary infection during a surgical operation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adhesive film having moisture permeability suitable for medical use and the like.

If adhesive films used for medical purposes are not moisture permeable, sweating from the skin will be inhibited, leading to itching.

Since it can cause problems such as rashes, it is desirable to have transparent properties above a certain limit. As a means for imparting moisture permeability, a method is generally adopted in which a pressure-sensitive adhesive is applied onto a moisture-impermeable film support such as polyvinyl chloride or polyethylene, and then mechanical holes are formed. In addition, in recent years, methods have been used to impart air permeability and moisture permeability by variously devising the form of the adhesive composition applied to the air permeable support. This method includes, for example, applying the adhesive composition in streaks, mixing a foaming agent into the adhesive composition,
A method in which a pressure-sensitive adhesive composition using an organic solvent that can be extracted at room temperature with an aqueous coagulated extract is applied, and then immersed in the extract to extract the organic solvent. There is a method of coagulating the agent composition to form a large number of continuous pores.

Second, conventional moisture permeability imparting means are extremely troublesome to manufacture, or have problems such as not being able to provide sufficient moisture permeability. In addition, all of the above methods form holes, pores, or discontinuous cross sections in the support or adhesive composition layer in some form, and do not form a continuous film, so they are not applicable to bats. It was limited to use as a combination emergency band, a hub containing a drug in an adhesive composition, or a patch, and was not suitable for use as a so-called surgical tape for preventing secondary infection during surgical operations.

In light of the above-mentioned circumstances, the present inventors have developed a new structure in which the support and adhesive composition have no holes, pores, or discontinuous cross sections, exhibit good moisture permeability, and are extremely flexible and stretchable.
As a result of intensive studies to develop a useful moisture-permeable adhesive, the present invention was completed.

That is, the present invention focuses on the moisture permeability and flexibility of a polyurethane film, and uses it as a support for an adhesive film.At the same time, the present invention develops a completely transparent pressure-sensitive adhesive film with a new structure in which polyurethane is also used as the main ingredient of the adhesive composition. It is not only easier to manufacture than the above-mentioned adhesive films made by the prior art, but also has characteristics that are extremely suitable as surgical tapes for medical use, especially surgical operations. be.

The details are described below.

As the polyurethane used in the support of the present invention, urethane resins commonly used for synthetic leather can be used.

That is, as a polyester component, adipate polyester polyol, isocyanate-modified polyester polyester polyester
The hydroxyl value is preferably 50 to G5. Also, as an isocyanate component, methylene sulphate (
Examples include 4-phenyl isocyane-1-), 1-lylene diisocyane-1., and naphthalene diisocyane-1-.

Regarding the reaction molar ratio of both components, in order to provide flexibility in consideration of fit to various parts of the human body, it is necessary to reduce isocyanene i to polyester, preferably to isocyanane i)-1. The blending ratio of polyester is 100%
It is desirable to use 30 to 60 parts per part. To form a polyurethane film, the above polyester and isocyanate 1- are mixed with methyl ethyl ketone. Dissolve in a solvent such as ethyl acetate to a solid content of about 35%, apply this solution to #l pattern paper using a doctor knife, and dry. After drying,
By peeling off the release paper, a single film (1) is obtained.
A range of 1m is suitable. In this case, it is also possible to give the surface of the support film a desired design by appropriately embossing the release paper. Furthermore, it is also possible to color the resin to human skin color using a suitable dye or pigment.

The polyurethane film obtained in this way has high moisture permeability and flexibility, and the value measured for a film with a thickness of 50 to 200 μn1 is 800 to 600 g/m.
'・2411r, elongation at break 500-300%, 1
00% modulus (stress at 100% stretching) is (1,5
~0.8 kg/mm2.

A millable type urethane elastomer is suitable as the polyurethane used in the adhesive composition of the present invention.

Millable type urethane elastomers are generally made by reacting polyester or polyether with less than an equivalent amount of isocyanate, and are usually supplied in a solid state, but there are also solution type urethane elastomers produced by solution reaction.

The adhesive composition contains the urethane elastomer and various additives used in general adhesives, such as tackifiers,
A softener can also be added.

Furthermore, when a high cohesive force is desired, this objective can be achieved by using a crosslinking agent such as isocyanate or peroxide. A phenolic resin is suitable as the tackifier, and the blending ratio is preferably 50 to 100 pbr (1 part to 10 parts of polyurethane, the same applies hereinafter).As the softener, polyethylene glycol and polypropylene glycol are crushed, and the blending ratio is 50 to 100 pbr. is preferably 2 to 10 pl+r.As the crosslinking agent, tolylene diisocyanate timer is suitable when the urethane elastomer to be used is based on tolylene diisocyanate 1 or more, and dicumyl peroxide or cumyl t- A peroxide such as butyl peroxide is suitable.The compounding ratio is preferably 1 to 3 layers.For the adhesive, such a compound is dissolved and dispersed in a solvent such as toluene to a solid content of about 25%. obtained by

Dissolution and dispersion can be carried out using a conventional mixer.

The present invention employs a method in which the pressure-sensitive adhesive composition prepared by the above-described method is formed into a film using a release paper in the same way as the support film, and after drying, it is bonded to a base film. That is, a solution of the polyurethane adhesive composition is applied onto release paper using a roll coater or the like, and after drying, the support polyurethane film is fed out from a separate unwinder and laminated.

The thickness of the adhesive layer is preferably 20 to 50 μm.

The adhesive film based on polyurethane of the present invention has excellent moisture permeability, similar to Base 41 film, and has 50 parts/m
The following thicknesses showed moisture permeability of 900 r4/m'·24br or more. This material may be used as a base adhesive for other adhesives, such as natural rubber, butyl rubber, or styrene-butadiene rubber.

Compared to polyisobutylene rubber, acrylic polymers, etc., even those based on acrylic polymer, which is said to have the highest moisture permeability, have a moisture permeability of about 50% at a thickness of 25μ...
The moisture permeability is 0 to 550g/m2・2411r, and the rest is extremely low, below 200g/m2・241+r.As a natural consequence of the extremely high moisture permeability of the moisture permeability support film and adhesive film, The moisture permeability of the adhesive film is also high, and the M'tW degree is 800 g/m2.
A value of about 24 II r can be easily obtained.

In order to investigate the lower limit of moisture permeability required for adhesive film C,
We created an adhesive film by applying the God's adhesive main ingredient to a polyurethane film support, and tested it by applying it to the skin. After 48 hours, the result was .3; no itchiness was felt at all. is 700q/m2・24 b r as moisture permeability
It was at the following times.

The moisture-permeable adhesive film of the present invention satisfies oral conditions and has excellent flexibility and stretchability, so it is suitable for medical use, and there is no discontinuity in the support and adhesive composition. It can be said to be a completely ambidextrous ζf product that is unrivaled by conventional products in terms of its structure and simple manufacturing method.

Examples of the present invention will now be described. In the following description, parts and % mean parts by weight and % by weight, respectively. In addition, the elongation at break of the support film in the examples,
100% Moji], lath and moisture permeability tests were conducted as follows.

Elongation at break and 100% modulus: A test piece with a width of 1 (in+m) and a length of i5 om was tested at 311.
Using a tensile tester based on 7721, the grip distance was 10 (l
n1 m, tensile speed: 30 (1 mm/min), and calculate the load when the elongation is 100% and the elongation rate when the test piece breaks. The 100% modulus was calculated using the following formula.

100% modulus = 10 + load at 1% elongation/' (thickness mm x width lll111 of test piece) Measurement was performed at 5 points,
Calculate the elongation at break and 100% modulus from the average value.

Transmission) Moderation - Based on II37-0208, moisture absorbent is used as K81
Measurement was performed using calcium chloride specified in 23 under temperature and humidity conditions of 4 () ± 0.5°C and 9 () ± 2% RH. Measurement is 3
Calculate the moisture permeability from the average value.

Example support film: 100 parts of adipic acid polyester having a molecular weight of about 2.000 and a hydroxyl value of about 50, 1 part of diphenyl and 1-5ti of methane diisocylene were dissolved in ethyl acetate to a solid content of about 35%. , the film thickness after drying on the release paper is about 5 (
) Use a knife coater to apply the coating to a thickness of 17 μm.

Next is C1! After drying for about 5 minutes in a drying oven at a temperature of 100° C., the film was left in a greenhouse at 60° C. for 5 days with the release paper attached to form a film.

The obtained polyurethane film has high flexibility and elasticity, and has a breaking elongation of 400%, 1 (1 (1% mogicolas 0,
! It was 1 kg/mm2.

Adhesive film: Urethane rubber (manufactured by Sumitomo Bayer, trade name Tsurepan 61)
1f)) if) [) parts, 80 parts of phenolic resin (manufactured by Yasuyu Co., Ltd., trade name YS Polyster 2130'), crosslinking agent (manufactured by Nippon Polyurethane Co., Ltd., trade name Herone 1---
A pressure-sensitive adhesive solution was prepared by dissolving 2 parts of L) in toluene to a solid content of about 25%. Next, add this solution to 11I
I pattern paper (manufactured by Soω1 Kakosha, product name E K 120t12
) was coated with a roll coater so that the thickness of the adhesive layer after drying was 3() μm, and the adhesive layer was left to dry in a drying oven at 100° C. for 3 minutes. A support film prepared in advance was pressed onto the coated product taken out from the drying oven using a pressure roll to produce an adhesive film. The moisture permeability of this adhesive film was extremely high at 80 (1 g/m2.24 mm), and even when it was applied to the skin, no rash or itching was felt at all after 48 hours.

Comparative Example 1 A commercially available acrylic adhesive (manufactured by Sosen Kagaku Co., Ltd., trade name SK Dyne 801!1) was applied and dried in the same manner as in the example, and then the support described in the example and Neulum were bonded together to form an adhesive film. was created. The moisture permeability of this adhesive film is 550g
/m2·24 br, and in the skin adhesion test, the area in contact with the skin became red for 48 hours, causing 75: bruising.

Comparative Example 2 Commercially available natural rubber adhesive (manufactured by Toyo Ink Co., Ltd., trade name BP)
S-2411) was applied and dried in the same manner as in the examples, and then the support film described in the examples was laminated to prepare an adhesive film.

The moisture permeability of the adhesive film on the mouth is 70g/m?・2411
r was extremely low, and when applied to the skin, the entire surface turned white and flaky after 48 hours, accompanied by itching.

Procedures Amendment Written July 22, 1981 Kazuo Wakasugi, Commissioner of the Patent Office 1, Special Application for Indication of Case No. 11435'0 1982, Title of Invention: Moisture Permeable Adhesive Film 6, Person Making Amendment Case Relationship with Patent Applicant Location 1-4-5 Marunouchi, Chiyoda-ku, Tokyo Name (2)
34) Sanyo Kokusaku Pulp Co., Ltd. President Nasu
Tadami 4, Agent 100 Address 264 Suiraku Building, 1-4-5 Marunouchi, Chiyoda-ku, Tokyo
Room No. 214-2861 (1ri Satoru γ・i 6, Column Z for detailed explanation of the invention in the specification subject to amendment. Contents of amendment The following points in the specification will be amended.

(1) On page 5, line 10, the phrase "For film with a thickness of 50 to 200 microns" has been corrected to "For a film with a thickness of 50 to 150 microns."

Claims (1)

[Scope of Claims] 1. A moisture-permeable adhesive film in which a polyurethane-based adhesive composition is coated on a polyurethane film support. 2 Moisture permeability of adhesive film is 7001m2・24 +1
The moisture-permeable pressure-sensitive adhesive film according to claim 1, wherein the moisture permeable adhesive film is r or more. 3 The mechanical properties of the adhesive film are 300 to 5 in terms of elongation at break.
00%, 100% modulus 0.4-0.8kg/
7. A wet adhesive film according to claim 1, which is mm2.