JPS61129118A - Elastic plaster - Google Patents

Abstract

PURPOSE:A plaster having improved expanding and contracting properties, drug releas ing effect, durability of medicinal effect, etc., obtained by forming a drug retaining layer consisting of a high-viscosity gelatinous base on one side (inner part layer) of elastic urethane foam, and laminating a pressure-sensitive adhesive layer in contact with the layer on it. CONSTITUTION:The drug retaining layer 2 consisting of a high-viscosity gelatinous base containing a drug such as methyl salicylate, etc. is formed on the inner part layer of one side of the substrate 1 comprising the elastic open-cell foamed urethane foam by a means such as packing, impregnation, etc. Further, the water-soluble or water-insoluble pressure-sensitive adhesive layer 3 is laminated to the layer in such a way that the drug retaining layer 2 is laminated to the layer in such a way that the adhesive layer is directly brought into contact with the drug retaining layer 2, to give an elastic plaster capable of keeping common adherent feeling by expansion and contraction of the substrate 1 even if this plaster is applied to the expanding and contracting part of the skin, having and improved drug releasing effect and durability of medicinal effect because of double layer structure of the drug retaining layer 2 and the pressure-sensitive adhesive layer 3. Before the plaster is used, the pressure- sensitive adhesive layer 3 is protected with the release layer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a patch that is particularly highly elastic and is applied to the skin surface.

(Prior art) Conventional patches are made by spreading a single-layer base on a support such as lint cloth, nonwoven fabric, or plastic film that has relatively poor elasticity, breathability, and heat retention. (Problems that the patch is applied to) When the patch is applied to a bending or stretching area of the skin, it tends to peel off easily.In order to apply a conventional patch to the bending or stretching area of the skin, a fixing bandage, bandage, or surgical tape is required. etc. must be used together. In order to eliminate this drawback, it is possible to strengthen the adhesive force by using a water-insoluble base on the patch surface, but when such a patch is applied to an elastic part of the skin, the drug release properties of the patch may be affected. In addition to chipping, adhesion causes a strong tensile feeling on the skin surface, causing discomfort in the colored areas.

With supports such as plastic films, lint cloths, and nonwoven fabrics in such patches, it is not possible to adjust air permeability, surface temperature, etc.

This invention aims to solve the above problems.

(Means for Solving the Problems) The configuration of the present invention will be described below according to embodiments shown in the drawings.

FIG. 1 is a sectional view of a stretchable adhesive patch (a) showing the structure of the present invention. (1) is a flexible, stretchable urethane foam that is used as a support for a stretchable patch, and the appropriate thickness for the support for the patch is about 2 mm.

A drug-retaining layer (2) is formed in the inner layer on one side of the urethane foam by filling or impregnating the cells (pores) of the urethane foam with a high viscosity gel base having the formulation shown below.

Example 1 A formulation example (by weight) of a high viscosity gel base having a layer thickness of 100 to 500 g/m'' is shown.

Gelatin 5 parts CMC-sodium 2 parts Sodium polyacrylate 1 part Glycerin 20 parts Water 72f
B: After forming a drug-retaining layer by filling or impregnating cells (pores) on one side of the urethane foam with a high-viscosity gel-like base consisting of the above formulation example, and gelling this,
Further, a water-soluble or water-insoluble adhesive layer (3) is laminated on one side of the urethane foam so as to be in direct contact with the drug-retaining layer.

In addition, (4) is a removable plastic film to protect the adhesive layer (3) when sold or not in use.
It is delamination.

Examples of the formulation of the base for the water-soluble or water-insoluble adhesive layer (3) are as shown below.

Example 2 A formulation example of a water-soluble adhesive base having a layer thickness of 100 to 500 g/m is as follows.

Gelatin 2 parts Polyvinyl alcohol 2B Sodium polyacrylate 5IIICMC-sodium 4 parts Kaolin 1 part Polybutene
1 part glycerin 20 parts water 65B Example 3 A formulation example of a water-insoluble adhesive base having a layer thickness of 50 to 200 g/m'' is as follows.

Raw rubber 52 parts Ester gum 20! Polybutene 103 ft Escolenots 15 parts Liquid paraffin 3 parts or less Data showing a comparative experiment of drug transfer speed between the patch according to the present invention and a known patch. A high viscosity gel base containing 2% methyl salicylate was applied to the cells (11 pores) on one side of the urethane foam to a thickness of 500.
Drug retention N(2
) was formed into a gel, and then the water-insoluble adhesive base of Example 3 was laminated with FIN100 g/m''.

On the other hand, the control drug used was a sample in which 2% methyl salicylate was blended into the base of the following formulation, and this was spread onto a non-woven fabric to a layer thickness of 500 g/m''.

Compounding ratio of base of control drug Gelatin 6B Polyvinyl alcohol 5 parts Sodium polyacrylate IB CMC-sodium 2B Kaolin 2 parts Polybutene 2 parts Glycerin 30B Water 52 parts 5 in Noyale
Percent agar gel (i diameter 10cm, height 5m) Fl
The samples were placed in the center of the agar gel at 37 degrees Celsius, the seven gel layers were replaced every 2 hours, and the methyl salicylate in the agar gel was measured using a conventional method. It is expressed as a quantity.

The results show the drug release effect and drug efficacy as shown in Figure 2.
s: to sex! ! This shows the fluff difference.

(Function) When the stretchable patch of this invention is applied to a bending or stretching part of the skin, the patch once applied will expand and contract as the skin expands and contracts due to the expansion and contraction of the support, and even if the skin stretches due to movement of the body. A normal adhesive layer can be maintained.

Furthermore, since it has a two-layer structure consisting of a drug-retaining layer and an adhesive layer, it has excellent drug release effects and long-lasting drug efficacy.

(Effects of the Invention) This invention uses a stretchable urethane foam as a retention layer, forms a drug retention layer made of a high viscosity gel base on the inner layer on one side of the urethane foam, and forms a drug retention layer on one side of the urethane foam. has a water-soluble or water-insoluble adhesive layer laminated in direct contact with the drug-retaining layer;
When applied, it has a good contact feeling to the skin, and even when applied to a moving part of the skin, there is no feeling of tension on the skin, and fixing supplies such as bandages, adhesive plasters, and surgical tape are not required.

Furthermore, since it has a two-layer structure consisting of a drug-retaining layer and an adhesive layer, it has an excellent drug release effect and a remarkable effect on the sustainability of drug efficacy.

[Brief explanation of drawings]

The drawings show examples of the present invention; □ Fig. 1 is an enlarged sectional view of a stretchable patch, and Fig. 2 is a graph showing the amount of salicylic acid transferred in the base layer of the patch. fa+...Stretchable poultice il+...Urethane foam (2)...Drug retention layer (3)...Adhesive layer (4:
・More than plastic film

Claims (2)

[Claims] (1) A stretchable urethane foam is used as a retention layer, and a drug retention layer made of a high viscosity gel base is formed on the inner layer on one side of the urethane foam, and the drug retention layer is formed on one side of the urethane foam. A stretchable adhesive patch comprising a water-soluble or water-insoluble adhesive layer laminated so as to be in direct contact with each other. (2) The stretchable adhesive patch according to claim 1, wherein the urethane foam is open-celled.