JP4205192B2 - Adhesive material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an adhesive material used for skin application in the medical hygiene field and the like, and more particularly to an adhesive material suitably used for an emergency adhesive bandage, a large adhesive bandage, a dressing material, a drape material and the like.
[0002]
[Prior art]
The medical patch is usually formed by providing a pressure-sensitive adhesive layer on one side of a base film, and is used by sticking to the skin surface to be applied via the pressure-sensitive adhesive layer.
[0003]
The base film in such a patch for medical use is mainly composed of soft polyvinyl chloride from the viewpoints of skin followability (flexibility), stretchability, and texture during application. ing.
[0004]
However, in general, soft polyvinyl chloride contains a large amount of plasticizer in order to impart flexibility, and this plasticizer migrates into the adhesive layer to reduce the cohesive force of the adhesive layer, resulting in an adhesive residue phenomenon. It has been pointed out that it has problems such as occurrence and decrease in adhesive strength. Furthermore, in recent years, from the viewpoint of emphasizing environmental problems, a movement to reduce the use amount of polyvinyl chloride resin containing chlorine as a halogen is progressing in each field.
[0005]
Therefore, polyurethane resins and polyolefin resins have been studied as polyvinyl chloride substitute resins, and have been studied and used as base films for medical use patches as in the present invention.
[0006]
[Problems to be solved by the invention]
However, although the base film made of the above-mentioned alternative resin is excellent in flexibility and stretchability, it may be uncomfortable when applied to the skin surface as a patch because it is an elastic body. Is still not fully satisfactory.
[0007]
Accordingly, the present invention has been made to solve the problems of the above-mentioned base film made of polyvinyl chloride and its substitutes, and uses a base film made of a polymer blend having a specific composition. As a result, it was found that a patch material satisfying characteristics such as flexibility, stretchability, and skin followability was obtained, and the present invention was completed.
[0008]
[Means for Solving the Problems]
That is, at least one selected from ethylene / 1-butene copolymer, ethylene / 1-octene copolymer, ethylene / methacrylic acid copolymer, ethylene / vinyl acetate copolymer, polypropylene / polybutene mixture, polyethylene / polybutene mixture. Of 50 to 90% by weight of a hydrocarbon elastomer, a styrene / isoprene / styrene triblock copolymer, a homopolymer of (meth) acrylic acid alkyl ester, and a copolymer containing (meth) acrylic acid alkyl ester as main components A pressure-sensitive adhesive layer is formed on a base film made of 10 to 50% by weight of a modifying polymer having a glass transition temperature of −30 to 30 ° C. The material is provided.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The adhesive material of the present invention is obtained by forming a pressure-sensitive adhesive layer on one side or both sides of a base film.
[0010]
The base film used for the patch of the present invention comprises a mixture of a hydrocarbon elastomer and a modifying polymer. Examples of hydrocarbon elastomers include ethylene / 1-butene copolymer, ethylene / 1-octene copolymer, ethylene / methacrylic acid copolymer, ethylene / vinyl acetate copolymer, polypropylene / polybutene mixture, polyethylene / polybutene mixture. A polyolefin-based resin that is at least one selected from the group consisting of:
[0011]
On the other hand, as the modifying polymer, a styrene / isoprene / isoprene triblock copolymer, a homopolymer of (meth) acrylic acid alkyl ester having an alkyl group having 4 to 18 carbon atoms, and a carbon number of 4 to 18 The polymer which is at least 1 type chosen from the copolymer which has as a main component the (meth) acrylic-acid alkylester which has an alkyl group is mentioned. The above-mentioned modifying polymer in the present invention has a glass transition temperature of -30 to 30 ° C, preferably -25 to 20 ° C. In other words, the use of a polymer having a glass temperature in the above range as the modifying polymer improves the balance of stress relaxation, flexibility, non-blocking properties, and the like.
[0012]
The mixing ratio of the hydrocarbon-based elastomer and the modifying polymer is such that the former is 50 to 90% by weight, preferably 55 to 80% by weight, and the latter is 10 to 50% by weight, preferably 20 to 45% by weight. Set to. In the case where the mixing ratio of the modifying polymer is less than the above range, the stress relaxation time of the obtained patch becomes long, and it becomes easy to cause a sense of incongruity when it is stuck on the skin surface. Moreover, when the mixing ratio of the modifying polymer exceeds the above range, the flexibility is improved so that the blocking phenomenon of the base film occurs. As a result, an anti-blocking measure is required at the time of manufacturing and storing the patch, which is inefficient.
[0013]
The base film obtained as described above is formed to have a thickness of about 10 to 200 μm, preferably about 20 to 100 μm, for use in the patch of the present invention. Further, the surface of the obtained film is preferably subjected to a treatment such as corona discharge treatment or a known primer coating in order to improve the anchoring property when the pressure-sensitive adhesive layer is formed.
[0014]
The base film used in the present invention is preferably adjusted so that the stress relaxation time is 200 seconds or shorter, preferably 100 seconds or shorter. When the stress relaxation time exceeds 200 seconds, there is a tendency to cause a sense of incongruity when the patch is applied. Furthermore, the substrate film is preferably adjusted to a range of 25% modulus is 25~100kg / cm ^2. When the 25% modulus is less than 25 kg / cm ² , the flexibility of the base material tends to increase and the handleability tends to decrease, and when it exceeds 100 kg / cm ² , the mechanical strength of the base material tends to be low. Since it increases and the rigidity also increases, it is not preferable because it cannot follow the movement of the skin during application, which may cause a sense of incongruity or increase skin irritation.
[0015]
An adhesive layer is formed on one side or both sides of the base film to produce the adhesive material of the present invention. The adhesive to be formed is not particularly limited as long as it is used as a medical adhesive. . Examples of the adhesive that can be preferably used include an acrylic adhesive, a rubber adhesive, and a silicone adhesive.
[0016]
The acrylic pressure-sensitive adhesive is preferably a homopolymer of a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 18 carbon atoms, preferably 4 to 12 carbon atoms, or other single unit having the ester as a main monomer. A copolymer obtained by copolymerizing a monomer (for example, a functional monomer) in an amount of 3 to 50% by weight, preferably 5 to 40% by weight, is used.
[0017]
Examples of the (meth) acrylic acid alkyl ester include esters such as butyl ester, hexyl ester, octyl ester, decyl ester, lauryl ester, stearyl ester, and these ester chains are linear or branched. Also good.
[0018]
Examples of the monomer that can be copolymerized with the ester include (meth) acrylic acid hydroxyalkyl esters such as (meth) acrylic acid 2-hydroxyethyl ester and (meth) acrylic acid 3-hydroxypropyl ester, Carboxyl group-containing unsaturated monomers such as (meth) acrylic acid, maleic acid, fumaric acid and crotonic acid; (meth) acrylamide and derivatives thereof such as (meth) acrylamide, dimethyl (meth) acrylamide and diethyl (meth) acrylamide; N-alkoxyalkyl (meth) acrylamides such as N-butoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, (meth) acrylic acid N, N-dimethylaminoethyl ester Such as ( Data) acrylic acid N, N- alkylaminoalkyl esters, functional monomers such as amide group-containing unsaturated monomers such as N- vinyl pyrrolidone. In addition to these functional monomers, non-functional monomers such as vinyl acetate, styrene, α-methylstyrene, and (meth) acrylonitrile can also be copolymerized.
[0019]
Examples of rubber-based pressure-sensitive adhesives that can be used for the pressure-sensitive adhesive layer include main rubbers such as natural rubber, polyisobutylene, polyisoprene, polybutene, styrene-isoprene (or butadiene) block copolymers, and ethylene-vinyl acetate copolymers. A tackifier such as a rosin resin, a terpene resin, a coumarone-indene resin, a terpene-phenol resin, or a petroleum resin can be blended and used as an auxiliary material in the material resin. Furthermore, if necessary, softening agents such as liquid polybutene, mineral oil, lanolin, and liquid polyisoprene, fillers such as titanium oxide and clay, and antioxidants such as butylhydroxytoluene may be appropriately blended. In addition, you may mix | blend such an auxiliary material with the said acrylic adhesive.
[0020]
Furthermore, as a silicone type adhesive which can be used as an adhesive, the adhesive etc. which have polydimethylsiloxane as a main component are mentioned.
[0021]
The pressure-sensitive adhesive layer having the above composition can be used as the patch of the present invention by being formed on the base film with a thickness of about 10 to 200 μm, preferably about 20 to 100 μm.
[0022]
【The invention's effect】
Since the patch of the present invention uses a specific substrate film as described above, there is no migration of a plasticizer or the like from the substrate film into the adhesive layer, and there is no change in adhesive properties. Moreover, since it is a specific base film, it is rich in flexibility (skin followability), stretchability, and stress relaxation properties, and does not feel uncomfortable during application.
[0023]
【Example】
Examples of the present invention will be described below and will be described in more detail. However, the present invention is not limited to these examples, and various applications are possible without departing from the technical idea of the present invention.
[0024]
Example 1
Hydrocarbon-based elastomer (Nippon Unicar over trade name NUC3530, ethylene / vinyl acetate copolymer) 70% by weight, styrene / isoprene / styrene triblock copolymer (manufactured by Kuraray Co., Ltd., trade name HYBRAR VS-1, A resin mixture comprising 30% by weight of a glass transition temperature (8 ° C.) was formed into a film to prepare a base film having a thickness of 50 μm.
[0025]
The obtained base film was subjected to corona discharge treatment on one side, and the surface tension of the film surface was reduced to 40 dyn / cm ² .
[0026]
Next, a pressure-sensitive adhesive layer having a thickness of 45 μm was formed on the treated surface of the base film subjected to the corona discharge treatment, and the pressure-sensitive adhesive layer surface was further coated with a separator to prepare the patch of the present invention. The pressure-sensitive adhesive used was obtained by copolymerizing a monomer mixture consisting of 95 parts by weight of 2-ethylhexyl acrylate and 5 parts by weight of acrylic acid in the presence of 0.1 part by weight of benzoyl peroxide using ethyl acetate as a solvent. It is the obtained acrylic adhesive.
[0027]
Example 2
Hydrocarbon-based elastomer (Mitsui Du Pont Polychemical Co., Ltd., trade name New Clermont 0908C, ethylene / methacrylic acid copolymer) 50 wt% and 70 wt parts / acrylonitrile 30 parts by weight of the acrylic polymer (butyl acrylate, the glass transition (Temperature -22 ° C.) A resin mixture comprising 50% by weight was formed into a film to prepare a base film having a thickness of 50 μm. A patch of the present invention was produced in the same manner as in Example 1 except that this film was used.
[0028]
Example 3
A patch of the present invention was produced in the same manner as in Example 1 except that the mixing ratio of the resin used in Example 1 was changed to 5/5.
[0029]
Comparative Example 1
Prepared in Example 1, a substrate film hydrocarbon-based elastomer (Nippon Unicar over trade name NUC3530, ethylene / vinyl acetate copolymer) except for forming only has an adhesive preparation in the same manner as in Example 1 did.
[0030]
Reference example 1
A patch was prepared in the same manner as in Example 1 except that the base film was formed from a soft polyvinyl chloride resin.
[0031]
The following characteristics were evaluated for the patches prepared in the above Examples, Comparative Examples, and Reference Examples, and the results are shown in Table 1.
[0032]
<Stress relaxation time>
Each patch was cut into a size of 2 cm × 10 cm, stretched 50% at a pulling speed of 300 mm / min, and while maintaining this state, the time until the stress at 50% stretching was 60% was measured.
[0033]
<25% modulus>
Each patch was cut into a size of 2 cm × 10 cm, pulled at room temperature at a tensile speed of 300 mm / min with a Tensilon tensile tester, and 25% modulus was measured.
[0034]
<Adhesive strength>
Each patch was cut into a size of 2 cm × 10 cm, adhered to a bakelite plate, and the end of the patch was pulled at a tensile speed of 300 mm / min with a Tensilon type tensile tester at room temperature. Degree peeling test).
[0035]
<Skin adhesiveness>
Each patch was cut into a size of 2 cm × 5 cm, and this was applied to the forearm portion of 10 volunteers for 2 hours, and the presence or absence of discomfort during the application was determined.
[0036]
[Table 1]

Claims (3)

At least one carbonization selected from an ethylene / 1-butene copolymer, an ethylene / 1-octene copolymer, an ethylene / methacrylic acid copolymer, an ethylene / vinyl acetate copolymer, a polypropylene / polybutene mixture, and a polyethylene / polybutene mixture. Selected from 50 to 90% by weight of hydrogen elastomer, styrene / isoprene / styrene triblock copolymer, homopolymer of (meth) acrylic acid alkyl ester, and copolymer mainly composed of (meth) acrylic acid alkyl ester An adhesive material, wherein a pressure-sensitive adhesive layer is formed on a base film composed of 10 to 50% by weight of a modifying polymer having a glass transition temperature of −30 to 30 ° C.  The patch according to claim 1, wherein the stress relaxation time of the substrate film is 200 seconds or less. 25% modulus of the base film, adhesive material of claim 1 wherein the 25~100kg / cm ^2.