JPH0371404B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] This invention relates to a patch. [Prior art and its problems] Conventionally, patches used for pain relief and anti-inflammation for stiff shoulders, bruises, sprains, etc. are made by adding tackifiers, softeners, fillers, anti-aging agents, etc. to natural or synthetic rubber. Adhesive balance is maintained by blending additives and their blending ratio. However, by incorporating medicinal ingredients such as menthol, methyl salicylate, glycol salicylate, camphor, borneol, and capsaicin at high concentrations, it is expected that the medicinal efficacy will improve, but the cohesive force of the bound paste will decrease, The adhesive properties of the base are lost. When applied to the human body, a plaster remains on the skin, significantly reducing commercial value. In addition, in recent years, there have been patches that use A-B-A type thermoplastic elastomer as a base, but in this case, when methyl salicylate is blended as a medicinal ingredient at a high concentration, the adhesive properties of the base are significantly impaired. This is because the medicinal ingredient methyl salicylate is A-
This is thought to be because the domain phase A of the B-A type thermoplastic elastomer is dissolved and the properties as a teleblock polymer are lost. In addition, conventional patches are made by simply spreading a plaster on a non-woven fabric, but there is a drawback that the plaster does not have a good affinity with the non-woven fabric, and the plaster leaches out onto the back side of the non-woven fabric. This invention has been made based on the above circumstances. That is, the object of the present invention is to provide AB-
It maintains the good adhesiveness and elasticity originally possessed by type A thermoplastic elastomer, and has a plaster with excellent adhesive properties and stability over time, and has good affinity between the plaster and the support. The object of the present invention is to provide a patch that does not ooze out onto the back surface of a support and has good adhesion to bending and stretching parts of the body. [Means for Solving the Problems] In order to solve the problems described above, the present inventors have proposed a method that can be blended into an A-B-A type thermoplastic elastomer, absorbs a medicinal ingredient, and forms a domain phase A. As a result of studying a number of substances such as magnesium aluminate metasilicate, microcrystalline cellulose, KC floc, starch, and lactose, which prevent the dissolution, plasticization, and softening of the base material and maintain good adhesive properties of the base material, we found that, among others, It was discovered that magnesium aluminate metasilicate is suitable, and furthermore, the stretchable nonwoven fabric made of specific constituent fibers and the plaster of a specific composition containing the A-B-A type thermoplastic elastomer have good affinity. We discovered this and arrived at this invention. That is, the outline of the present invention is to provide a paste containing an A-B-A type thermoplastic elastomer, an alicyclic saturated hydrocarbon resin, liquid paraffin, a medicinal ingredient, and magnesium aluminate metasilicate;
This is a patch characterized by forming constituent fibers made of polyamide and polyester into a sheet shape, bonding the constituent fibers with an acrylic adhesive, and spreading the constituent fibers onto a stretchable nonwoven fabric. The A-B-A type thermoplastic elastomer is an A-B-A type thermoplastic elastomer consisting of a hard polymer A and a soft polymer B.
It is an elastomer with a mold structure, and the A block is a hard polymer end block made of a vinyl compound such as polystyrene or polymethylstyrene, and its glass transition temperature is 70°C or higher.
Polymer blocks having an average molecular weight in the range from 1,000 to 500,000 are useful. Further, the B block is a soft polymer midblock of a conjugated diene compound such as butadiene or isoprene, and has a glass transition temperature in the range of -100 to 30°C and an average molecular weight in the range of about 4,500 to 1,000,000. Polymer blocks are effective. Examples of such A-B-A type thermoplastic elastomers include styrene-isoprene-styrene thermoplastic elastomers, styrene-butadiene-styrene thermoplastic elastomers, and the like, with styrene-isoprene-styrene thermoplastic elastomers being particularly preferred. Examples of the alicyclic saturated hydrocarbon resin include hydrocarbons obtained by polymerizing aromatic hydrocarbons (having 9 to 12 carbon atoms) including styrene, α-methylstyrene, vinyltoluene, indene, methylindene, and the like. Hydrogenated thermoplastic resins that have an alicyclic structure by adding hydrogen to the resin, hydrogenated resins obtained by polymerizing cyclopentadiene or dicyclopentadiene, hydrogenated aromatic petroleum resins, conjugated A resin obtained by cyclizing and dimerizing a diene monomer, polymerizing it in the same way as other petroleum resins, and then hydrogenating it; a resin obtained by copolymerizing an alicyclic compound with an aromatic compound or an aliphatic compound. Examples include hydrogenated products of resins and mixtures thereof, among which styrene, α
- Thermoplastic hydrogen made into an alicyclic structure by adding hydrogen to a hydrocarbon resin obtained by polymerizing aromatic hydrocarbons (9 to 12 carbon atoms) including methylstyrene, vinyltoluene, indene, methylindene, etc. Polymer resins are preferred, and such alicyclic saturated hydrocarbon resins are commercially available under the trade name Alcon (manufactured by Arakawa Chemical Co., Ltd.). As the liquid paraffin, those specified in the Japanese Pharmacopoeia can be suitably used. The medicinal ingredients include, for example, methyl salicylate, glycol salicylate, salicylic acid, menthol, peppermint oil, camphor, thymol, acrinol, funnel extract, chlorpheniramine maleate, diphenhydramine, benzyl nicotinic acid ester, capsicum extract, Nonylic acid vanylamide, capsaicin, ibuprofen,
Examples include indomethacin, alklofenac, ketoprofen, flobiprofen, fenoprofen and its esters, corticosteroids, etc., and one or more of these may be blended. _For example, the magnesium aluminate metasilicate has the following compositional formula, has a specific surface area of 200 to ₃₀₀ ^{m 2} _{/ g} , and has an oil absorption of 2 to 4.
ml/g fine particles are preferable, and those with the product name ``Neushilin UFL ₂ '' (manufactured by Fuji Chemical Industry) are preferable.
It can be obtained commercially as . This magnesium aluminate metasilicate is particularly excellent in absorbing salicylic acids among the above-mentioned medicinal ingredients. The patch according to the present invention has a paste containing the A-B-A thermoplastic elastomer, alicyclic saturated hydrocarbon resin, liquid paraffin, a medicinal ingredient, and magnesium aluminate metasilicate. However, in the present invention, it is believed that the magnesium aluminate metasilicate absorbs the medicinal ingredient, thereby preventing the medicinal ingredient from dissolving the end block phase of the A-B-A type thermoplastic elastomer. Therefore, the amount of magnesium aluminate metasilicate is 1 to 20% by weight, preferably 5 to 14% by weight of the medicinal ingredient, and 0.2 to 15% by weight, preferably 1 to 15% by weight of the total paste. The content is preferably 5% by weight. The amounts of other components in the paste may be the usual mixing ratios for patches, such as the above-mentioned A
-B-A thermoplastic elastomer is 10 to 50% by weight, preferably 15 to 45% by weight, and the alicyclic saturated hydrocarbon resin is 10 to 70% by weight, preferably 30 to 60% by weight.
% by weight, liquid paraffin is 1 to 30% by weight, preferably 5 to 25% by weight, and the medicinal ingredient is 0.01 to 50% by weight, preferably 0.01 to 25% by weight. There is no particular restriction on the means for blending the above-mentioned components to obtain the paste in this patch, and for example, a kneader mixer can be used. In the patch according to the present invention, a paste obtained by mixing the above-mentioned components is spread on a support. One of the important aspects of this invention is the use of a stretchable nonwoven fabric with a specific fiber composition as a support. That is, the support is formed by forming the constituent fibers into a sheet shape, including at least polyamide and polyester as constituent fibers, including rayon if necessary, and bonding the constituent fibers with an acrylic adhesive. It is a stretchable nonwoven fabric that has stretchability in one direction or two directions. The stretchable nonwoven fabric having at least polyester and polyamide as its constituent fibers contains an A-B-A type thermoplastic elastomer, an alicyclic saturated hydrocarbon resin, liquid paraffin, a medicinal ingredient, and magnesium aluminate metasilicate. It has excellent compatibility with plasters containing the following, and has excellent adhesion to bending and stretching parts of the body. In order to fully exhibit the advantages of the support, 35 to 75 parts of polyamide and 20 to 60 parts of polyester must be used.
parts, preferably 10 parts or less of rayon. Non-woven fabrics made of polyamide are flexible but lack bulk and volume, while non-woven fabrics made of polyester are not flexible but have excellent bulk and volume. The above blending ratio is selected in order to form a nonwoven fabric. Furthermore, the reason why the rayon is blended in the above blending amount is to prevent delamination of the nonwoven fabric due to an increase in the amount of hygroscopic binder impregnated. Moreover, it is preferable that the support exhibits elasticity of 20 to 100%.
This is because the elasticity of the skin is about 20 to 100%, so if the elasticity is less than 20%, this patch will not follow the bending and stretching of the body, and if the elasticity is greater than 100%, it will not follow the body's bending and stretching. There is no advantage of being large either. Note that nonwoven fabrics whose fibers are not bonded with an acrylic adhesive do not have the 20% elasticity. The method for spreading the paste onto the support may be a calender roll method, a solvent method, or the like. The patch of the present invention has been explained above, but
In addition to the above-mentioned components, the present invention does not preclude the addition of other components depending on the properties required for the adhesive patch. Examples of such other components include excipients such as kaolin, bentonite, calcium carbonate, zinc oxide, and titanium oxide, tackifier resins such as petroleum resins, polyterpene resins, rosin and rosin-modified resins, and the medicinal ingredients described above. Accelerators for promoting dissolution and absorption, such as isopropyl myristate, polypropylene glycol, crotamiton,
Examples include diethyl sebacate, preservatives such as boric acid, and other additives commonly used in this type of patch, such as anti-aging agents and softeners. [Effects of the Invention] According to the present invention, the following various effects can be achieved. That is, since magnesium aluminate metasilicate is specifically blended into the paste, the end block phase of the A-B-A type thermoplastic elastomer is prevented from being dissolved and plasticized by the medicinal ingredient.
As a result, it is possible to maintain most of the good adhesion and elasticity of the base containing the A-B-A type thermoplastic elastomer, and to create a patch that has a paste with excellent adhesive properties and stability over time. can be provided. In addition, this patch has excellent stability over time, so there is no deterioration in quality due to long-term storage, and it has excellent adhesion and affinity to human skin, is highly flexible, and does not stick to the skin when removed. It has various advantages such as not causing pain and leaving no plaster residue after removal. Since a stretchable nonwoven fabric with a specific fiber composition is used as the support, it has good compatibility with a plaster containing an A-B-A type thermoplastic elastomer.
Therefore, it is possible to prevent the paste from oozing out onto the back side of the stretchable nonwoven fabric during storage or use of this adhesive patch. Moreover, since this support is stretchable, even if this patch is applied to the bending/stretching parts of the body, it can be prevented from peeling off due to intense exercise. [Examples] Next, the present invention will be specifically explained by showing examples and test examples of the present invention. (Example 1) 25 parts of a styrene-isoprene-styrene thermoplastic elastomer (trade name: Caulifix TR1107, manufactured by Shell Chemical Co., Ltd.) was impregnated with 15 parts of light liquid paraffin (Japanese over-the-counter product) to obtain an impregnated mixture. Next, 45 parts of Alcon P-85 (manufactured by Arakawa Chemical Co., Ltd.), 2 parts of titanium oxide (manufactured by Sakai Chemical Co., Ltd.), and 1.5 parts of magnesium aluminate metasilicate (manufactured by Fuji Chemical Industry Co., Ltd.) were then heated in a temperature range of 90 to 110°C. The impregnated mixture was kneaded with a mixer [trade name: KDHU-2 model, manufactured by Fuji Denki Kogyo Co., Ltd.], and then 2.5 parts of methyl salicylate, 3 parts of DL-camphor, and DL-menthol were added as medicinal ingredients. 7.5 parts were added and mixed to obtain a paste. 250 g of this plaster (A) was mixed with a stretchable nonwoven fabric (a unidirectional stretchable nonwoven fabric whose constituent fibers are 55 parts of nylon, 40 parts of polyester, and 5 parts of rayon, and an acrylic adhesive as a binder, manufactured by Nippon Vilene Co., Ltd.).
A patch was obtained by uniformly applying the mixture to 1 m ² . (Test Example 1) For the following specimens A and B, each 6cm x 9cm
They were cut to size and affixed to the outside of the elbows of 20 adult males. The adult male was asked to perform an elbow bending and stretching exercise 100 times, and the number of peelings of the patch was measured every 10 times (the patch was judged to have peeled off when more than half of the patch had peeled off). The adhesion was investigated. The results are shown in Table 1 as cumulative values. Specimen A: patch obtained in Example 1. Specimen B: 250g of plaster obtained in Example 1 was bleached and then coated with latex undercoat three times.
Patch applied to m ² . Specimen C: A patch obtained in the same manner as in Example 1 except that microcrystalline cellulose [trade name: Avicel, manufactured by Asahi Kasei Corporation] was used instead of magnesium aluminate metasilicate.

[Table] As shown in Table 1 above, the patch of the present invention has good adhesion to the skin despite intense bending and stretching movements. (Test Example 2) The same samples A, B, and
10 sheets of each C were stored at 70°C for 8 weeks, and every week the color difference between the back of the support and the back of another support not coated with plaster was measured using a color machine manufactured by Nippon Denshoku Kogyo. The leaching of the plaster to the back surface of the support over time was investigated. The evaluation results are shown in Table 2.

[Table] As shown in Table 2, it can be seen that in the patch according to the present invention, there is little leaching of the plaster to the back surface of the support over time.

Claims (1)

[Claims] 1 A plaster containing an A-B-A type thermoplastic elastomer, an alicyclic saturated hydrocarbon resin, liquid paraffin, a medicinal ingredient, and magnesium aluminate metasilicate is made of polyamide and a patch comprising polyester constituent fibers formed into a sheet shape and then spread onto a stretchable nonwoven fabric formed by bonding the constituent fibers with an acrylic adhesive. 2 The A-B-A type thermoplastic elastomer is
The patch according to claim 1, which is a styrene-isoprene-styrene block copolymer.