JP5581534B2 - Adhesive, adhesive sheet using the adhesive, and production method thereof - Google Patents

Description

  The present invention relates to an adhesive having excellent water absorption and transparency. More specifically, the present invention relates to a pressure-sensitive adhesive having a novel structure composed of a hydrophobic substance and a hydrophilic substance, a pressure-sensitive adhesive sheet using the pressure-sensitive adhesive, and methods for producing them.

  Conventionally, a pressure-sensitive adhesive containing a hydrophobic substance and a hydrophilic substance has been used for various applications. For example, it is used as a covering means for protecting wounds, stomas, fistulas, pressure ulcers, etc., and absorbing body fluids therefrom, and for protecting pressure ulcers and for reducing pressure.

In general, the following properties are required for the pressure-sensitive adhesive effectively used in various fields.
(1) Sufficient water absorption is ensured against sweat, exudate, etc. generated from the skin.
(2) Sufficient shape retention even after absorbing sweat or exudate.

  Here, as a technique for improving the properties required for the pressure-sensitive adhesive as described above, for example, in Patent Document 1, a thermoplastic elastomer and an oil or higher fatty acid that is a softening agent necessary for the base polymer are used as a base polymer. A technique is disclosed in which a specific hydrophilic polymer aqueous solution can be dispersed without using an emulsifier (surfactant) and water can be blended.

  In Patent Document 2, hydrocolloid is dissolved and gelled with a non-volatile swelling agent that is compatible with hydrocolloid, and then the hydrocolloid gel mass is pulverized to form swollen hydrocolloid particles. A technique for improving the water vapor permeability and peel strength of a pressure-sensitive adhesive by dispersing it in a solution containing a pressure-sensitive adhesive composition is disclosed.

  Patent Document 3 contains diclofenac sodium, a polyhydric alcohol, and a water-absorbing filler. By incorporating this polyhydric alcohol into the adhesive layer in a compatible state, diclofenac sodium, which is a drug, can be effectively transdermally used. Alternatively, a technique capable of transmucosal absorption is disclosed.

  Incidentally, a conventional pressure-sensitive adhesive containing a hydrophobic substance and a hydrophilic substance generally has a structure in which a hydrophilic substance is dispersed in a continuous phase made of a hydrophobic substance.

JP 59-212429 A Japanese National Patent Publication No. 05-503863 Japanese Patent Laid-Open No. 10-45579

  As described above, a conventional pressure-sensitive adhesive containing a hydrophobic substance and a hydrophilic substance has been developed to improve its properties from various directions by devising the components contained therein.

  However, even if the components contained in the pressure-sensitive adhesive are devised, the basic structure of the hydrophobic substance and the hydrophilic substance is similar, and therefore the pressure-sensitive adhesive satisfying the above requirements (1) and (2) There is still nothing, and there was a limit to dramatically improve the properties necessary for adhesives such as water absorption.

  For example, in the technique described in Patent Document 2, since the swollen hydrocolloid particles obtained by pulverizing the hydrocolloid gel mass are dispersed in a solution containing the pressure-sensitive adhesive composition, the transparency is lowered by the edge. was there. There is also a problem that the pulverization process is troublesome.

  Therefore, the main object of the present invention is to provide a pressure-sensitive adhesive having a novel structure that satisfies all the requirements (1) and (2) and can dramatically improve water absorption and transparency.

  In order to solve the above problems, the inventor of the present application pays attention to the structure of the hydrophobic substance and the hydrophilic substance in the pressure-sensitive adhesive composition, and eagerly pursues a method for dramatically improving the properties required for the pressure-sensitive adhesive composition. As a result of research, the present inventors have succeeded in forming a new structure by changing the idea from a general structure in which a hydrophilic substance is dispersed in a continuous phase made of a hydrophobic substance, and completed the present invention.

That is, in the present invention, first, a pressure-sensitive adhesive containing a hydrophobic substance, a hydrophilic substance, and a polyhydric alcohol,
In the continuous phase formed of the hydrophobic substance, the hydrophilic substance swollen by the polyhydric alcohol exists continuously and / or discontinuously,
5 to 55% by weight of the hydrophilic substance, 2 to 45% by weight of the polyhydric alcohol,
A pressure-sensitive adhesive having a water absorption rate represented by the following formula (1) of 90% or more after 60 minutes is provided.
As long as the pressure-sensitive adhesive according to the present invention has the above structure and has the water absorption rate, the water absorption achievement rate is not particularly limited, but the water absorption achievement rate represented by the following formula (2) is 60 minutes later. It is preferable that it is 40% or more.
Further, the light transmittance of the pressure-sensitive adhesive according to the present invention is not particularly limited, but the light transmittance at 660 nm is preferably 10% or more.

Next, in the present invention, a pressure-sensitive adhesive containing a hydrophobic substance, a hydrophilic substance, and a polyhydric alcohol,
In the continuous phase formed of the hydrophobic substance, the hydrophilic substance swollen by the polyhydric alcohol exists continuously and / or discontinuously,
A hydrophobic material comprising 3-30 wt% thermoplastic elastomer, 0-35 wt% tackifier, 0-35 wt% softener, and 0-40 wt% liquid rubber;
10-50% by weight of a hydrophilic substance;
An adhesive comprising 2 to 35% by weight of a polyhydric alcohol is provided.
The detailed composition ratio of these pressure-sensitive adhesives according to the present invention is not particularly limited as long as the effects of the present invention are not impaired, but the thermoplastic elastomer is 10 to 25% by weight, the softening agent is 2 to 10% by weight, and the tackifier. 5 to 35% by weight, liquid rubber 5 to 30% by weight, hydrophilic substance 20 to 40% by weight, and polyhydric alcohol 2 to 20% by weight.

The pressure-sensitive adhesive according to the present invention described above can be suitably used, for example, for the pressure-sensitive adhesive layer of a pressure-sensitive adhesive sheet including at least a support layer and a pressure-sensitive adhesive layer on at least one side of the support layer.
Although the usage purpose of this adhesive sheet is not specifically limited, For example, it can be used for wounds.

Next, in the present invention, a method for producing a pressure-sensitive adhesive comprising a hydrophobic substance, a hydrophilic substance, and a polyhydric alcohol,
A mixing step of mixing the hydrophobic substance and the hydrophilic substance;
A swelling step of swelling the hydrophilic substance in the mixture with the polyhydric alcohol after the mixing step;
At least
5 to 55% by weight of the hydrophilic substance, 2 to 45% by weight of the polyhydric alcohol,
Provided is a pressure-sensitive adhesive production method in which the water absorption represented by the formula (1) is 90% or more after 60 minutes.

In the present invention, there is further provided a method for producing a pressure-sensitive adhesive sheet comprising at least a support layer and a pressure-sensitive adhesive layer provided on at least one side of the support layer,
A mixing step of mixing a hydrophobic substance and a hydrophilic substance;
A swelling step of swelling the hydrophilic substance in the mixture with the polyhydric alcohol after the mixing step;
By doing at least
5 to 55% by weight of the hydrophilic substance, 2 to 45% by weight of the polyhydric alcohol,
A pressure-sensitive adhesive having a water absorption rate represented by the formula (1) of 90% or more after 60 minutes,
A sheet forming step of providing the pressure-sensitive adhesive on at least one side of the support layer;
The manufacturing method of the adhesive sheet which performs is provided.

  Here, technical terms used in the present invention will be described.

  The “continuous phase” used in the present invention is a concept different from “dispersed phase” or “dispersed” in which a phase composed of a predetermined substance is completely covered with another phase and exists in the form of dots. The phase which consists of a phase which continuously spreads at least linearly or planarly without being completely covered with other phases. The “sheeting step” used in the present invention is a step of providing an adhesive layer on at least one side of the support layer, and the technology for providing it is not limited.

  The adhesive according to the present invention has a hydrophilic substance swollen by a polyhydric alcohol continuously and / or discontinuously in a continuous phase formed of a hydrophobic substance. It is possible to dramatically improve the properties required for the adhesive.

It is a conceptual schematic diagram which shows 1st Embodiment of the specific structure of the adhesive 1 which concerns on this invention. It is a conceptual schematic diagram which shows 2nd Embodiment of the specific structure of the adhesive 1 which concerns on this invention. It is a schematic cross section which shows 1st Embodiment of the adhesive sheet 10 which concerns on this invention. It is a schematic cross section which shows 2nd Embodiment of the adhesive sheet 10 which concerns on this invention. It is a model perspective view which shows 3rd Embodiment of the adhesive sheet 10 which concerns on this invention. It is a flowchart of the manufacturing method of the adhesive 1 which concerns on this invention, and the manufacturing method of the adhesive sheet 10. FIG. It is a drawing substitute photograph which shows the result of having image | photographed the state of each test piece after being immersed in 37 degreeC physiological saline for 24 hours in an Example. It is a drawing substitute photograph which shows the result of having image | photographed the state of each test piece after being immersed in 37 degreeC physiological saline for 24 hours in a comparative example. It is a drawing substitute photograph which shows the result of having image | photographed the state of each test piece after being immersed in 37 degreeC physiological saline for 48 hours in a comparative example. It is a drawing substitute photograph which image | photographed the state of the Example, the comparative example, and the raw material hydrophilic substance.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments for carrying out the invention will be described with reference to the drawings. In addition, embodiment described below shows an example of typical embodiment of this invention, and, thereby, the range of this invention is not interpreted narrowly.

<Adhesive>
The pressure-sensitive adhesive 1 according to the present invention is a pressure-sensitive adhesive containing at least a hydrophobic substance 11, a hydrophilic substance 12, and a polyhydric alcohol 13, and includes a large amount in a continuous phase formed of the hydrophobic substance 11. The hydrophilic substance 12 swollen by the monohydric alcohol 13 exists continuously and / or discontinuously. Thus, when the hydrophilic substance 12 is swollen and exists in the continuous phase formed of the hydrophobic substance 11, the water absorption represented by the formula (1) is 90% or more after 60 minutes. I succeeded in improving it.

  The presence form of the pressure-sensitive adhesive 1 according to the present invention is not particularly limited as long as it exists in the continuous phase formed of the hydrophobic substance 11 in a state where the hydrophilic substance 12 is swollen. For example, as shown in FIG. 1, the swollen hydrophilic substance 12 can be continuously present in the continuous phase formed of the hydrophobic substance 11. Alternatively, as shown in FIG. 2, the swollen hydrophilic substance 12 can be discontinuously present in the continuous phase formed of the hydrophobic substance 11. Furthermore, although not shown, it is possible to mix a portion where the swollen hydrophilic material 12 is continuously present and a portion where it is discontinuously present in the continuous phase formed of the hydrophobic material 11. It is.

  The pressure-sensitive adhesive according to the present invention is not particularly limited as long as it has the above-described structure and has the above-mentioned water absorption rate, and the water absorption rate represented by the formula (1) is 150% or more after 60 minutes. More preferably, it is more preferably 200% or more. In addition, since the upper limit of a water absorption rate is based on a hydrophobic component, it is not particularly limited, but is preferably about 1000%.

  Since the pressure-sensitive adhesive 1 according to the present invention exhibits the above structural features, the time until the water absorption reaches the maximum (initial water absorption speed) is remarkably faster than that of the conventional pressure-sensitive adhesive. This is presumably because the hydrophilic substance 12 exists in the continuous phase formed of the hydrophobic substance 11 in a swollen state.

  Although a specific water absorption achievement rate is not particularly limited, the water absorption achievement rate represented by the formula (2) is preferably 40% or more after 60 minutes. The faster the water absorption rate is, the greater the amount of sweating that can be handled, and so the maceration of the skin can be prevented.

  Since the pressure-sensitive adhesive 1 according to the present invention exists in a continuous phase formed of the hydrophobic substance 11 in a state where the hydrophilic substance 12 is swollen, its transparency is remarkably higher than that of the conventional pressure-sensitive adhesive. This is because the hydrophilic substance 12 present in the continuous phase formed of the hydrophobic substance 11 is in a swollen state, so that the surface of the hydrophilic substance 12 is smooth and no light is reflected or scattered. It is believed that there is. In order to obtain more transparency, it is preferable that the hydrophilic substance 12 be transparent (having light transmittance) when swollen with the polyhydric alcohol 13.

  The specific light transmittance is not particularly limited, but the light transmittance at 660 nm is preferably 10% or more, and more preferably 15% or more. The higher the transparency, the more visible the state of a wound, skin, etc. from the outside when a covering material using an adhesive is applied. As a result, there is no need to peel off and check the covering material as in the conventional case, so that the pain, hygiene, confirmation and replacement trouble, skin irritation, and cost of the patient when removing the covering material are eliminated. .

  As long as the pressure-sensitive adhesive 1 according to the present invention described above has the above-described structure and has the above-described water absorption, the specific constituent components thereof are not particularly limited. The component which can be used suitably for the adhesive 1 which concerns on this is demonstrated.

(1) Hydrophobic substance 11
The pressure-sensitive adhesive 1 according to the present invention includes a hydrophobic substance 11. The hydrophobic substance 11 is present in a state where a continuous phase is formed in the pressure-sensitive adhesive 1 according to the present invention. The content of the hydrophobic substance 11 in the present invention is not particularly limited as long as the effects of the present invention are not impaired, but the range of the hydrophobic substance is preferably 20 to 93% by weight with respect to the total weight of the adhesive, 45 More preferably, it is -70 weight%. This is because by setting the content of the hydrophobic substance to 20% by weight or more, it is possible to prevent disintegration due to water absorption, decrease in adhesiveness, and decrease in transparency. Moreover, it is because the fall of water absorption can be prevented by setting content of a hydrophobic substance to 93 weight% or less.

  As the hydrophobic substance 11 used in the pressure-sensitive adhesive 1 according to the present invention, the type is not limited as long as a continuous phase can be formed. For example, an elastomer can be used.

  The elastomer that can be used in the pressure-sensitive adhesive 1 according to the present invention is not particularly limited as long as it can form a continuous phase, and one or more known ones can be freely selected. Examples include styrene-based, acrylic-based, urethane-based, silicone-based, and polyvinyl ether-based polymers. Styrene polymers include styrene-butadiene rubber, styrene-isoprene-styrene block copolymer (SIS), styrene-butadiene-styrene block copolymer (SBS), and styrene-ethylene / propylene-styrene block copolymer (SEPS). ), Styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / ethylene / propylene-styrene block copolymer (SEEPS), hydrogenated styrene-butadiene rubber (HSBR), styrene-ethylene / butylene- Olefin crystal block copolymer (SEBC), urethane copolymer, acrylic copolymer, olefin crystal-ethylene / butylene-olefin crystal block copolymer (CEBC), polyisobutylene, natural rubber, polyisopropylene Mention may be made of down, the nitrile rubber. In the present invention, it is particularly preferable to select and use a thermoplastic elastomer among them.

  For acrylics, urethanes, silicones, and polyvinyl ethers, select the monomers and determine the degree of polymerization so that appropriate initial adhesive strength and adhesive retention can be obtained at the stage of synthesizing the caking composition. Can be made. It is also possible to blend several types synthesized as required. For example, in the case of acrylic, using various monomers such as methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, butyl acrylate, and other monomers such as vinyl acetate Can be polymerized. They can also be blended after individual polymerization.

  In the present invention, among the elastomers, a styrene elastomer is preferably used, and hydrogenated styrene-butadiene rubber (HSBR) is more preferably used.

  In this invention, it is preferable that the range of a thermoplastic elastomer is 3-30 weight% with respect to the adhesive whole weight, and it is more preferable that it is 10-25 weight%. This is because by setting the elastomer content to 3% by weight or more, collapse due to water absorption can be prevented. Further, by setting the content of the elastomer to 30% by weight or less, the pressure-sensitive adhesive does not become hard and the pressure-sensitive adhesive force is easily developed, so that it can be suitably used.

  Here, as the hydrophobic substance 11 in the present invention, although not essential, a softener, a tackifier, a liquid rubber, and the like can be contained.

  By adding a softening agent, the elasticity of the hydrophobic substance 11 is reduced to give flexibility and also increase the tackiness. The kind of softener that can be used in the pressure-sensitive adhesive 1 according to the present invention is not particularly limited as long as the object of the present invention is not impaired, and a known softener can be freely selected. As an example, 1 type (s) or 2 or more types can be selected and used from mineral oil, vegetable oil, animal oil, and synthetic oil.

  Examples of the mineral oil include liquid paraffin, liquid isoparaffin, and naphthenic oil.

  Examples of vegetable oils include olive oil, olive squalane, macadamia nut oil, jojoba oil, almond oil, peanut oil, castor oil, palm oil, palm oil, safflower oil, sunflower oil, cottonseed oil, hardened palm oil, hardened palm oil, Avocado oil, apricot kernel oil, grape seed oil and the like can be mentioned.

  Examples of animal oils include lanolin, turtle oil, beeswax, squalene, pristane and the like.

  Synthetic oils include, for example, fatty acid triglycerides such as glycerin tri-2-ethylhexanoate; silicone oils such as polymethylphenylsiloxane, polydimethylsiloxane, and aminosilicon; isopropyl myristate, octyldodecyl myristate, isononyl isononanoate, Examples include esters such as isopropyl palmitate and ethylhexyl palmitate.

  In the present invention, among the softening agents, mineral oil is preferably used, and liquid paraffin is more preferably used.

  In the present invention, the range of the softening agent is preferably 0 to 35% by weight, more preferably 1 to 25% by weight, and further preferably 2 to 10% by weight with respect to the total weight of the pressure-sensitive adhesive. More preferred. This is because by setting the content of the plasticizer to 35% by weight or less, it is possible to make it difficult for cohesive failure while imparting appropriate flexibility.

  The kind of tackifier which can be used for the pressure-sensitive adhesive 1 according to the present invention is not particularly limited as long as the object of the present invention is not impaired, and a known tackifier can be freely selected. Examples include natural rosin derivatives, coumarone-indene resins, terpene oligomers, aliphatic petroleum resins, alkyl-modified phenol resins, polyterpene resins, gum rosins, rosin esters, oily phenol resins, coumarone indene resins, petroleum hydrocarbon resins, etc. Can be mentioned.

  In the present invention, among the tackifiers, it is preferable to use a petroleum-based hydrocarbon resin or the like, and it is more preferable to use an alicyclic saturated hydrocarbon resin.

  In this invention, it is preferable that the range of a tackifier is 0 to 50 weight% with respect to the adhesive whole weight, and it is more preferable that it is 5-35 weight%. Considering the relationship with other compositions, the range of the tackifier is preferably 0 to 35% by weight with respect to the total weight of the pressure-sensitive adhesive. It is because moderate tackiness can be imparted by setting the content of the tackifier to 35% by weight or less.

  The kind of liquid rubber that can be used for the pressure-sensitive adhesive 1 according to the present invention is not particularly limited as long as the object of the present invention is not impaired, and a known liquid rubber can be freely selected. Examples include liquid isoprene rubber (LIR), liquid styrene-isoprene rubber (LSIR), liquid ethylene / propylene rubber (LEPR), liquid styrene-ethylene / propylene rubber (LSEPR), and liquid polyisobutylene having a viscosity average molecular weight of 30,000 to 100,000. And liquid polybutene.

  The liquid rubber lowers the elasticity of the hydrophobic substance 11 to give flexibility and also increases the adhesiveness. From the viewpoint of compatibility, the combination of styrene elastomer and liquid paraffin is preferably LIR and / or LSIR for SIS, liquid butadiene rubber for SBS, LEPR and / or LSEPR, HSBR for SEPS. For example, a combination of LEPR, LSEPR, liquid polyisobutylene, liquid polybutene, or a liquid rubber made of a mixture thereof is conceivable. By making such a compatible combination, even when the blending ratio of the liquid rubber is increased, that is, when flexibility is to be increased, bleeding of the liquid rubber and adhesive residue at the time of peeling can be prevented.

  In the present invention, the range of the liquid rubber is preferably 0 to 40% by weight, more preferably 1 to 35% by weight, and further preferably 5 to 30% by weight with respect to the total weight of the pressure-sensitive adhesive. More preferred. Considering the relationship with other compositions, the range of the liquid rubber is preferably 0 to 40% by weight with respect to the total weight of the pressure-sensitive adhesive. This is because by setting the content of the liquid rubber to 40% by weight or less, the cohesive failure can be made difficult.

  In the present invention, it is preferable to use HSBR as the hydrophobic substance 11 and a liquid rubber composed of LEPR, LSEPR, liquid polyisobutylene, liquid polybutene, or a mixture thereof as the liquid rubber. .

  The liquid rubber may be a crosslinked one, and it is effective to mix appropriately for the purpose of improving the cohesiveness. Furthermore, it is preferable that the weight ratio of the styrene elastomer and the liquid paraffin is in the range of 6: 1 to 1: 1.

(2) Hydrophilic substance 12
Since the pressure-sensitive adhesive 1 according to the present invention contains the hydrophilic substance 12, it can absorb sweat, exudate, and the like generated from the skin. Moreover, since this hydrophilic substance 12 exists in the continuous phase formed with the hydrophobic substance 11 in the state swollen with the polyhydric alcohol 13 mentioned later, compared with the conventional adhesive, water absorption power is remarkable. Succeeded in achieving improvement. In the present invention, the hydrophilic substance means a hydrophilic substance that does not contain a polyhydric alcohol.

  The hydrophilic substance 12 used for the pressure-sensitive adhesive 1 according to the present invention is not limited as long as it can be swollen by a polyhydric alcohol 13 described later, and the hydrophilic substance 12 can be used for a known pressure-sensitive adhesive. One or two or more substances can be freely selected and used. Moreover, as a hydrophilic substance, what is powdery or granular is preferable.

  For example, corn starch, guar gum, locust bean gum, starch, alginate, carrageenan, agar, gelatin, chitin, chitosan pectin, karaya gum, gum arabic, xanthan gum, dextran, sodium carboxymethylcellulose, carboxymethylcellulose, hydroxyalkylmethylcellulose, methylcellulose, starch Acetate, starch phosphate, hydroxyethylated starch, hydroxypropyl starch, oxidized starch, dextrinized starch, starch / acrylic acid graft polymer, polyacrylic acid, polyethylene oxide, polyvinyl alcohol, poly N-vinylpyrrolidone, kaolin, sulfur-containing Aluminum silicate, quaternium-18 hectorite, silica, talc, metasilicate Magnesium aluminate, and the like. In addition, as a hydrophilic substance, what has transparency after swelling is preferable.

  In the present invention, it is preferable to use carboxymethyl cellulose (CMC) among the hydrophilic substances.

  In the present invention, the range of the hydrophilic substance is 5 to 55% by weight, more preferably 10 to 50% by weight, and still more preferably 20 to 40% by weight with respect to the total weight of the pressure-sensitive adhesive. . This is because the water absorption required by the pressure-sensitive adhesive according to the present invention can be achieved by setting the content of the hydrophilic substance to 5% by weight or more. Further, by setting the content of the hydrophilic substance to 55% by weight or less, it is possible to prevent the collapse at the time of water absorption, the decrease in adhesive strength, and the decrease in transparency.

  In the present invention, the hydrophilic substance 12 may be water-soluble or water-insoluble as long as it is a substance that absorbs water.

(3) Polyhydric alcohol 13
In the pressure-sensitive adhesive 1 according to the present invention, a polyhydric alcohol 13 is used to swell the hydrophilic substance 11. The polyhydric alcohol 13 used in the pressure-sensitive adhesive 1 according to the present invention is not limited as long as it can swell the hydrophilic substance 12, and one or more known polyhydric alcohols can be freely used. Can be selected and used.

  For example, ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, glycerin, trimethylolpropane, pentaerythritol, xylitol, sorbitol, mannitol and the like can be mentioned. In addition, polyhydric alcohol polymers such as diethylene glycol, dipropylene glycol, triethylene glycol, polypropylene glycol, tetraethylene glycol, diglycerin, polyethylene glycol, triglycerin, tetraglycerin, and polyglycerin can also be used. As the polyhydric alcohol, glycerin is preferably used.

  In the present invention, the range of the polyhydric alcohol 13 is 2 to 45% by weight, more preferably 2 to 35% by weight, and even more preferably 2 to 20% by weight with respect to the total weight of the pressure-sensitive adhesive. This is because by setting the content of the polyhydric alcohol to 2% by weight or more, the water absorption required by the pressure-sensitive adhesive according to the present invention can be achieved. Further, by setting the content of the polyhydric alcohol to 45% by weight or less, it has a sufficient holding power and does not collapse at the time of water absorption and can be suitably used as an adhesive sheet.

  The total of the hydrophilic substance and the polyhydric alcohol is preferably 30% by weight or more and less than 55% by weight. This is because the water absorption rate can be further increased by setting the total of the hydrophilic substance and the polyhydric alcohol to 30% by weight or more. Moreover, transparency can be improved more by setting the sum total of a hydrophilic substance and a polyhydric alcohol to less than 55 weight%.

  Furthermore, it is preferable that polyhydric alcohol / hydrophilic substance <0.85. This is because by reducing the ratio of the polyhydric alcohol to the hydrophilic substance to less than 0.85, the cohesive force can be further improved and the stability can be further increased.

(3) Others Although not essential, the pressure-sensitive adhesive 1 according to the present invention may contain a pH adjuster. The kind of pH adjuster is not particularly limited as long as the object of the present invention is not impaired, and a known pH adjuster can be freely selected. Examples include pectin, anhydrous citric acid, alkali metal hydroxides, and organic acid buffers.

  In the present invention, it is preferable to use anhydrous citric acid among the pH adjusting agents. Moreover, it is preferable to adjust to the range of pH 4.0-6.0 according to the pH of normal skin.

  Although it is not essential, the adhesive 1 which concerns on this invention can also contain a medicinal component. The kind of medicinal component is not particularly limited as long as the object of the present invention is not impaired, and can be freely selected according to the object. Examples include bioactive agents, antibacterial agents, anti-inflammatory analgesics, steroids, anesthetics, antifungal agents, bronchodilators, antitussives, coronary vasodilators, antihypertensive agents, antihypertensive diuretics, antihistamines, hypnotic sedatives, All drugs such as tranquilizers, vitamins, sex hormones, antidepressants, cerebral circulation improving agents, antiemetics and antitumor agents can be added. These drugs exert their effects systemically or locally through percutaneous absorption, or exert their effects locally at the site where they are applied.

  Among the above-mentioned medicinal ingredients, it is preferable to add a bioactive agent that exhibits a local effect to the adhesive 1 according to the present invention for the purpose of maintaining or improving the physiological function of the skin (skin barrier function, etc.). . Specific examples of bioactive agents include sphingolipids, urea, glycolic acid, amino acids (arginine, cysteine, glycine, lysine, proline, serine, etc.) and their derivatives, protein hydrolysates (collagen, elastin, keratin, etc.), mucopolysaccharides (Hyaluronic acid, chondroitin sulfate, heparin, etc.) and derivatives thereof, vitamin B group (thiamine, riboflavin, nicotinic acid, pyridoxine, pyridoxal, pyridoxamine, biotin, folic acid, cyanocobalamin, etc.), ascorbic acid (vitamin C and its derivatives), retinoid (Vitamin A, retinal, retinoic acid, etc.), vitamin D (D2, D3, etc.), vitamin E and its derivatives, carotenoids (carotene, lycopene, xanthophyll, etc.), enzymes, coenzymes and the like can be mentioned. These may be used singly or in combination of two or more.

  The pressure-sensitive adhesive 1 according to the present invention described above has a remarkably high holding power in addition to its high water-absorbing power, water-absorbing speed, and transparency as compared with conventional pressure-sensitive adhesives. The specific holding force of the pressure-sensitive adhesive 1 according to the present invention is not particularly limited, but the holding force measured by the method of the example described later is preferably 60 minutes or more, more preferably 120 minutes or more, and 240 minutes. More preferably, it is the above.

  Since the pressure-sensitive adhesive 1 according to the present invention is present in a continuous phase formed of the hydrophobic substance 11 in a state where the hydrophilic substance 12 is swollen, the pressure-sensitive adhesive 1 has higher flexibility than the conventional pressure-sensitive adhesive. Therefore, the adhesive 1 is deformed along the unevenness of the skin and the like, and the adhesion to the skin is also improved. As a result, the amount of tackifier can be reduced. And the burden (stimulation) to the skin at the time of peeling can be reduced significantly.

<Adhesive sheet>
The pressure-sensitive adhesive 1 according to the present invention can be suitably used for the pressure-sensitive adhesive layer 102 of the pressure-sensitive adhesive sheet 10 including at least a support layer 101 and a pressure-sensitive adhesive layer 102 on at least one side of the support layer 101. Hereinafter, the adhesive sheet 10 using the adhesive 1 according to the present invention for the adhesive layer 102 will be described in detail.

  FIG. 3 is a schematic cross-sectional view schematically showing the pressure-sensitive adhesive sheet 10 according to the present invention. The pressure-sensitive adhesive sheet 10 according to the present invention is roughly provided with at least a support layer 101 and a pressure-sensitive adhesive layer 102. The form of the pressure-sensitive adhesive sheet 10 according to the present invention is not particularly limited as long as it includes the support layer 101 and the pressure-sensitive adhesive layer 102. For example, a polygon such as a triangle, a quadrangle, and a rhombus, a circle, an ellipse, or these The sheet can be formed into a free form such as a sheet form obtained by appropriately combining the shapes, a tape form formed continuously in a specific direction, a roll form, and the like. Further, it can be freely designed such as forming three-dimensionally according to the part to be attached, or providing a cut or slit. Details of each layer will be described below.

(1) Support layer 101
The support layer 101 of the pressure-sensitive adhesive sheet 10 according to the present invention is provided for the purpose of supporting a pressure-sensitive adhesive layer 102 described later. The form of the support layer 101 is not particularly limited as long as it can support the adhesive layer 102, and can be freely designed using any material. For example, forms, such as fiber sheets, such as a nonwoven fabric, a knitted fabric, and a woven fabric, a plastic film, a foam sheet, and paper, are mentioned. In the present invention, among these, a plastic film is particularly preferable from the viewpoints of flexibility, stretchability, moderate water vapor permeability, fungus barrier properties, and the like.

  When the support layer 101 made of a fiber sheet is employed for the pressure-sensitive adhesive sheet 10 according to the present invention, examples of the material include cellulose fibers such as cotton, viscose rayon, polynosic, copper ammonia rayon, and lyocell, polyester fibers. Acrylic fiber, polyamide fiber, polyolefin fiber, polyurethane fiber, vinylon fiber, polyvinyl chloride fiber, polyvinylidene chloride fiber and the like. In addition, although these materials may be used independently, it is also free to mix and use 2 or more types.

  When the support layer 101 made of a plastic film is used for the pressure-sensitive adhesive sheet 10 according to the present invention, examples of the material include polyurethane; polyester such as polyethylene terephthalate and polybutylene terephthalate; polyamide such as nylon 6 and nylon 66; polyethylene , Polyolefins such as low density polyethylene, high density polyethylene, polypropylene; ethylene / vinyl acetate copolymer (EVA), ethylene / ethyl acrylate copolymer (EEA), ethylene / methyl acrylate copolymer (EMA), ethylene / methyl Olefin copolymers such as methacrylate copolymer (EMMA), ethylene / methacrylic acid polymer (EMAA), ethylene / acrylic acid copolymer (EAA); polyvinyl alcohol; polyvinyl chloride, polychlorinated Vinylidene; silicone, and the like. In the present invention, among these, polyurethane, polyester, polyamide, etc. are preferable because they have good water vapor permeability and do not disturb insensitive transpiration. In addition, although these materials may be used independently, it is also free to mix and use 2 or more types.

  When the support layer 101 made of a foam sheet is used for the pressure-sensitive adhesive sheet 10 according to the present invention, examples of the material include polyolefin, polyurethane, acrylic, chloroprene rubber, and silicone.

  When the support layer 101 made of paper is employed for the pressure-sensitive adhesive sheet 10 according to the present invention, examples of the material include high-quality paper, craft paper, glassine paper, and coated paper.

  The support layer 101 of the pressure-sensitive adhesive sheet 10 according to the present invention can be formed into a single form with a single material, but can also be formed into a composite form using two or more kinds of materials. . Moreover, it can also be set as the support layer 101 of the laminated structure which laminated | stacked the support layer of the same or different kind of form.

  The thickness of the support layer 101 of the pressure-sensitive adhesive sheet 10 according to the present invention is not particularly limited as long as the object of the present invention is not impaired, but from the viewpoints of supporting the pressure-sensitive adhesive layer 102, operability at the time of application, and feeling of pressure on the skin. Therefore, 1 to 100 μm is preferable, and 5 to 50 μm is more preferable.

(2) Adhesive layer 102
The pressure-sensitive adhesive layer 102 of the pressure-sensitive adhesive sheet 10 according to the present invention is provided in a state of being laminated on at least one side of the support layer 101 in order to attach the pressure-sensitive adhesive sheet 10 and the skin. The pressure-sensitive adhesive layer 102 is formed by the pressure-sensitive adhesive 1 according to the present invention described above. Since the structure, composition, and other characteristics of the pressure-sensitive adhesive 1 are the same as those of the pressure-sensitive adhesive 1 described above, description thereof is omitted here.

  The thickness of the pressure-sensitive adhesive layer 102 of the pressure-sensitive adhesive sheet 10 according to the present invention is not particularly limited as long as the object of the present invention is not impaired, but is preferably 0.05 to 10 mm, more preferably 0.1 to 2 mm. preferable. This is because an appropriate adhesive strength is exhibited at the time of application, and excellent adhesion and followability to the skin are exhibited.

(3) Release sheet 103
In addition to the support layer 101 and the pressure-sensitive adhesive layer 102, the pressure-sensitive adhesive sheet 10 according to the present invention can be provided with a release sheet 103, although it is not essential. By providing the release sheet 103, the adhesive layer 102 can be protected from contamination and the like, and the handleability of the adhesive sheet 10 can be simplified.

  For the release sheet 103 of the pressure-sensitive adhesive sheet 10 according to the present invention, any material conventionally used in this field, such as a synthetic resin film or paper, can be used. For example, the surface of a paper or film is treated with a silicone resin treatment or a fluororesin treatment.

  Without providing the release sheet 103, for example, as shown in FIG. 4, the surface of the support layer 101 opposite to the surface on which the adhesive layer 102 is laminated (hereinafter referred to as “rear surface 1011”) is peeled off. Form the pressure-sensitive adhesive sheet 10 in a form formed or surface-treated with possible materials (see (I) in FIG. 4), use a plurality of the pressure-sensitive adhesive sheets 10 in a stacked state and peel them one by one. Is also possible (see (II) in FIG. 4). In addition to the method of laminating a plurality of pressure-sensitive adhesive sheets 10, as shown in FIG. 5, the pressure-sensitive adhesive sheet 10 formed in a similar manner can be formed into a roll.

  Thus, when the release sheet 103 is not provided, the support layer 101 plays the role of the release sheet 103 at the same time by subjecting the back surface 1011 to a silicone resin treatment, a fluorine resin treatment, or the like.

  The pressure-sensitive adhesive sheet 10 according to the present invention described above can be used for various applications, but when used for wounds in particular, the wound healing effect can be dramatically improved as compared with conventional pressure-sensitive adhesive sheets. is there. This is considered to be due to the high water absorption and water absorption speed of the pressure-sensitive adhesive 1 used for the pressure-sensitive adhesive sheet 10.

<Method for producing pressure-sensitive adhesive>
The part shown by the code | symbol 20 in FIG. 6 is a flowchart of the manufacturing method of the adhesive 1 which concerns on this invention. The method for producing a pressure-sensitive adhesive according to the present invention is roughly divided into a method of performing at least the mixing step 21 and the swelling step 22. Hereinafter, each process will be described.

(1) Mixing step 21
The mixing step 21 is a step of mixing the hydrophobic substance 11 and the hydrophilic substance 12. Any known technique can be freely used for the mixing method. For example, mixing can be performed using a pressure kneader or the like.

  The number of times of mixing in the mixing step 21 is not particularly limited, and can be set as appropriate in accordance with the compounding component and the compounding ratio of the pressure-sensitive adhesive. Moreover, temperature conditions can also be set suitably by heating and cooling as needed.

  When the above-mentioned softener, tackifier, liquid rubber or the like is included in the adhesive, it may be mixed in advance with a hydrophobic substance 11 such as an elastomer. You may mix.

  In this mixing step 21, a structure in which the hydrophilic substance 12 is dispersed in the continuous phase formed of the hydrophobic substance 11 is formed.

(2) Swelling step 22
The swelling step 22 is a step of swelling the hydrophilic substance 12 dispersed in the mixture by adding the polyhydric alcohol 13 to the mixture prepared in the mixing step 21 and further mixing. In addition, when making the hydrophilic substance 12 contain the pH adjuster mentioned above, it may be mixed with the hydrophilic substance 12 in advance, or may be mixed together in this swelling step 22.

  As described above, in the method for producing an adhesive according to the present invention, the hydrophobic substance 11 and the hydrophilic substance 12 are mixed to once form the same structure as the conventional adhesive, and then the polyhydric alcohol 13 is added. By swelling the hydrophilic substance 12, the hydrophilic substance 12 in a swollen state can be present continuously and / or discontinuously in the continuous phase formed by the hydrophobic substance 11 (FIG. 1 and FIG. 1). (See FIG. 2).

<The manufacturing method of the adhesive sheet 10>
The part shown with the code | symbol 200 in FIG. 6 is a flowchart of the manufacturing method of the adhesive sheet 10 which concerns on this invention. The manufacturing method of the pressure-sensitive adhesive sheet 10 according to the present invention is roughly divided into a method of performing at least the sheet forming step 203 after performing the pressure-sensitive adhesive manufacturing method 20 that performs at least the mixing step 21 and the swelling step 22. Since the pressure-sensitive adhesive manufacturing method 20 is the same as described above, only the sheet forming step 203 will be described below.

  The sheet forming step 203 is a step of providing the pressure-sensitive adhesive layer 102 containing the pressure-sensitive adhesive 1 on at least one surface of the support layer 101. The sheet forming step 203 can freely use any known technique. For example, the pressure-sensitive adhesive 1 according to the present invention manufactured by the pressure-sensitive adhesive manufacturing method 20 is rolled onto the support layer 101 so as to have an appropriate thickness while applying pressure or the like. At this time, heating or the like may be performed as necessary.

  As another example, the pressure-sensitive adhesive 1 according to the present invention manufactured by the pressure-sensitive adhesive manufacturing method 20 is once applied to the release sheet 103 and then bonded to the support layer 101 to form the pressure-sensitive adhesive layer 102. You can also

  The specific coating method of the pressure-sensitive adhesive 1 on the support layer 101 or the release sheet 103 is not particularly limited, and any known method can be freely adopted. For example, using a coating method such as comma direct, knife coater, or gravure direct, the coating pattern and thickness can be appropriately controlled according to the purpose.

  Moreover, as a coating pattern of the adhesion layer 102, although the surface of the support layer 101 may be coat | covered entirely, it can also coat | cover partially. When covering partially, arbitrary forms, such as a grid | lattice form, a net form, a granular form, and an arabesque pattern, can be selected. Thus, by providing the adhesive layer 102 partially on one side of the support layer 101, air permeability, moisture permeability, etc. can be further improved, and stimulation at the time of peeling from the skin can be further reduced. You can also.

  During the production of the pressure-sensitive adhesive sheet 10 according to the present invention, the support layer 101 may be subjected to surface treatment or primer treatment in order to improve the adhesion between the support layer 101 and the pressure-sensitive adhesive layer 102. As the surface treatment of the support layer 101, for example, any known treatment method such as embossing, sand matting, corona discharge treatment, plasma treatment, alkali treatment, etc. can be employed. The primer treatment can be performed using any known primer as long as it is a primer that can be used for the pressure-sensitive adhesive according to the present invention, for example, using a primer composed of a silane coupling agent or the like. .

  Hereinafter, the present invention will be described in more detail based on examples. In addition, the Example demonstrated below shows an example of the typical Example of this invention, and, thereby, the range of this invention is not interpreted narrowly.

(1) Preparation of adhesive First, the adhesive which concerns on Examples 1-12 and Comparative Examples 1-7 was produced by the method shown below.

<Example 1>
HSBR (manufactured by JSR Corporation, the same shall apply hereinafter) 7.2% by weight as an example of an elastomer, liquid paraffin (manufactured by Kaneda Corporation, the same shall apply hereinafter) 4.8% by weight as an example of a softener, polyisobutylene (Shin Nippon Oil) Chemical Co., Ltd.) 10.0% by weight and 21.0% by weight of an alicyclic saturated hydrocarbon resin (Arakawa Chemical Co., Ltd., the same shall apply hereinafter) as an example of a tackifier are charged in a pressure kneader. Mix until uniform. Next, as examples of hydrophilic substances, CMC-Na (manufactured by Daicel Chemical Industries, Ltd., the same shall apply hereinafter) 40.0% by weight, gum arabic (manufactured by Gokyo Sangyo Co., Ltd.) 5.0% by weight, karaya gum (Gokyo Sangyo) 10.0% by weight was added and mixed under pressure until uniform. Thereafter, 2.0% by weight of glycerin (manufactured by Sanyo Kasei Kogyo Co., Ltd., hereinafter the same) was added as an example of a polyhydric alcohol, and the mixture was further mixed to swell the hydrophilic substance to produce a pressure-sensitive adhesive according to Example 1. .

<Example 2>
A pressure kneader is charged with 20.1% by weight of HSBR as an example of an elastomer, 15.3% by weight of liquid paraffin as an example of a softening agent, and 29.6% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier. And mixed until uniform. Next, 5.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Then, 30.0 weight% of glycerol was added as an example of a polyhydric alcohol, and it further mixed, and produced the adhesive which concerns on Example 2. FIG.

<Example 3>
As an example of an elastomer, SIS (manufactured by JSR Corporation, the same shall apply hereinafter) 11.4% by weight; as an example of a liquid rubber, polybutene (manufactured by Nippon Petrochemical Co., Ltd.) 3.8% by weight; Co., Ltd.) 23.0% by weight and 16.3% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier were charged in a pressure kneader and mixed until sufficiently uniform. Next, 22.3% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 22.3% by weight of glycerin as an example of a polyhydric alcohol and 0.9% by weight of anhydrous citric acid as a pH adjusting agent were added and further mixed to prepare a composition according to Example 3.

<Example 4>
HSBR 20.3% by weight as an example of an elastomer, 8.5% by weight of liquid paraffin as an example of a softening agent, 10.3% by weight of polyisobutylene, and an alicyclic saturated hydrocarbon resin 20.3 as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 23.8% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 15.8% by weight of glycerin as an example of a polyhydric alcohol and 0.9% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Example 4.

<Example 5>
HSBR 10.8% by weight as an example of elastomer, 3.6% by weight of liquid paraffin as an example of a softening agent, 12.3% by weight of polyisobutylene, and 24.8 of an alicyclic saturated hydrocarbon resin as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, as an example of a hydrophilic substance, 22.2% by weight of CMC-Na and 10.0% by weight of Karaya gum were added and mixed under pressure until uniform. Thereafter, 15.5% by weight of glycerin as an example of a polyhydric alcohol and 0.8% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Example 5.

<Example 6>
HSBR 13.4% by weight as an example of elastomer, 4.5% by weight of polybutene as an example of liquid rubber, 11.9% by weight of polyisobutylene, and 34.2% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier % Was charged in a pressure kneader and mixed until sufficiently uniform. Next, 25.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 10.0% by weight of glycerin as an example of a polyhydric alcohol and 1.0% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Example 6.

<Example 7>
SIS 7.0% by weight as an example of elastomer, 3.0% by weight of liquid paraffin as an example of a softener, 25.0% by weight of polyisobutylene, and 15.0 of an alicyclic saturated hydrocarbon resin as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 20.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 30.0% by weight of glycerin was added as an example of a polyhydric alcohol and further mixed to prepare a composition according to Example 7.

<Example 8>
HSBR 20.0% by weight as an example of an elastomer, 10.0% by weight of liquid paraffin as an example of a softening agent, 20.0% by weight of polyisobutylene, and alicyclic saturated hydrocarbon resin 5.0 as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, CMC-Na 5.0 weight% and Karaya gum 10.0 weight% were added as an example of a hydrophilic substance, and it pressure-mixed until it became equal. Thereafter, 30.0% by weight of glycerin was added as an example of a polyhydric alcohol and further mixed to prepare a composition according to Example 8.

<Example 9>
SIS 12.0% by weight as an example of an elastomer, 5.0% by weight of liquid paraffin as an example of a softening agent, 30.0% by weight of polyisobutylene, 13.0% of an alicyclic saturated hydrocarbon resin as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 34.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, glycerin (5.0% by weight) as an example of a polyhydric alcohol and citric acid anhydride (1.0% by weight) as a pH adjuster were added and further mixed to prepare a composition according to Example 9.

<Example 10>
HSBR 18.0% by weight as an example of elastomer, 5.0% by weight of liquid paraffin as an example of a softening agent, 20.0% by weight of polyisobutylene, 22.0% of an alicyclic saturated hydrocarbon resin as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 22.5% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 12.0% by weight of glycerin as an example of a polyhydric alcohol and 0.5% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Example 10.

<Example 11>
HSBR as an example of an elastomer, 3.4% by weight of liquid paraffin as an example of a softener, 3.4% by weight of polybutene as an example of a liquid rubber, 11.7% by weight of polyisobutylene, As an example, 21.0% by weight of an alicyclic saturated hydrocarbon resin was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 24.0% by weight of CMC-Na and 10.0% by weight of Karaya gum were added as an example of a hydrophilic substance, and mixed under pressure until uniform. Thereafter, glycerin (5.0% by weight) as an example of a polyhydric alcohol and 1.0% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Example 11.

<Example 12>
HSBR 18.4% by weight as an example of elastomer, 7.9% by weight of liquid paraffin as an example of a softening agent, 11.3% by weight of polyisobutylene, 12.5% of an alicyclic saturated hydrocarbon resin as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, CMC-Na10.0 weight% and Karaya gum 4.0 weight% were added as an example of a hydrophilic substance, and it pressure-mixed until it became equal. Thereafter, 35.0% by weight of glycerin as an example of a polyhydric alcohol and 1.0% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Example 12.

<Comparative Example 1>
HSBR 24.3 wt% as an example of an elastomer, liquid paraffin 16.2 wt% as an example of a softener, polyisobutylene 22.3 wt%, an alicyclic saturated hydrocarbon resin 28.7 as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 8.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 0.5% by weight of glycerin was added as an example of a polyhydric alcohol, and further mixed to prepare a composition according to Comparative Example 1.

<Comparative example 2>
JIS 10.3% by weight as an example of an elastomer, 6.9% by weight of polybutene as an example of a liquid rubber, and 20.3% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier are charged in a pressure kneader, Mix until sufficiently uniform. Next, as an example of a hydrophilic substance, CMC-Na 30.0% by weight, Karaya gum 10.0% by weight, gum arabic 10.0% by weight, pectin (manufactured by Sanki Co., Ltd.) 10.0% by weight are added uniformly. Pressure mixing was performed until Thereafter, 2.0% by weight of glycerin as an example of a polyhydric alcohol and 0.5% by weight of anhydrous citric acid as a pH adjuster were added and further mixed to prepare a composition according to Comparative Example 2.

<Comparative Example 3>
A pressure kneader is charged with 12.4% by weight of HSBR as an example of an elastomer, 6.3% by weight of liquid paraffin as an example of a softening agent, and 21.3% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier. And mixed until uniform. Next, 10.0% by weight of Karaya gum was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 50.0% by weight of glycerin was added as an example of a polyhydric alcohol and further mixed to prepare a composition according to Comparative Example 3.

<Comparative example 4>
A pressure kneader is charged with 5.1% by weight of HSBR as an example of an elastomer, 4.3% by weight of liquid paraffin as an example of a softening agent, and 10.6% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier. And mixed until uniform. Next, 65.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Then, 15.0 weight% of glycerol was added as an example of a polyhydric alcohol, and it mixed further, and the composition concerning the comparative example 4 was produced.
In Comparative Example 4, it was powdery and could not be created. This is probably because the total amount of the hydrophilic substance and the polyhydric alcohol was too large, and the phase was reversed by water absorption.

<Comparative Example 5>
SIS 3.4% by weight as an example of elastomer, 2.8% by weight of polybutene as an example of liquid rubber, 4.2% by weight of polyisobutylene, 9.6% by weight of alicyclic saturated hydrocarbon resin as an example of a tackifier % Was charged in a pressure kneader and mixed until sufficiently uniform. Next, 25.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 55.0% by weight of glycerin was added as an example of a polyhydric alcohol and further mixed to prepare a composition according to Comparative Example 5.

<Comparative Example 6>
HSBR 15.3% by weight as an example of an elastomer, 7.6% by weight of liquid paraffin as an example of a softening agent, 15.3% by weight of polyisobutylene, and 29.8 of an alicyclic saturated hydrocarbon resin as an example of a tackifier % By weight was charged in a pressure kneader and mixed until it was sufficiently uniform. Next, 2.0% by weight of CMC-Na was added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 30.0% by weight of glycerin was added as an example of a polyhydric alcohol, and further mixed to prepare a composition according to Comparative Example 6.

<Comparative Example 7>
A pressure kneader is charged with SIS 15.5% by weight as an example of an elastomer, 10.3% by weight of liquid paraffin as an example of a softening agent, and 33.7% by weight of an alicyclic saturated hydrocarbon resin as an example of a tackifier. And mixed until uniform. Next, CMC-Na 20.0% by weight and Karaya gum 20.0% by weight were added as an example of a hydrophilic substance and mixed under pressure until uniform. Thereafter, 0.5% by weight of anhydrous citric acid was added as a pH adjuster and further mixed to prepare a composition according to Comparative Example 7.

  Moreover, as Comparative Examples 8 to 14, commercially available products were used as follows.

<Comparative Example 8>
As Comparative Example 8, a commercially available visitorm (registered trademark, manufactured by Bristol-Myers Squibb Co., Ltd.) was used.

<Comparative Example 9>
As Comparative Example 9, commercially available Tegasorb Thin (registered trademark, manufactured by 3M Company) was used.

<Comparative Example 10>
As Comparative Example 10, commercially available Absolute Cure (registered trademark, manufactured by Nitto Denko Corporation) was used.

<Comparative Example 11>
As Comparative Example 11, commercially available Duoactive ET (registered trademark, manufactured by Bristol-Myers Squibb Co., Ltd.) was used.

<Comparative Example 12>
As Comparative Example 12, a commercially available duoactive CGF (registered trademark, manufactured by Bristol-Myers Squibb Co., Ltd.) was used.

<Comparative Example 13>
As Comparative Example 13, a commercially available tegasorb (registered trademark, manufactured by 3M Company) was used.

<Comparative example 14>
As Comparative Example 14, a commercially available product, Comfield Alcus (registered trademark, manufactured by Coloplast Co., Ltd.) was used.

(2) Measurement of water absorption rate The pressure-sensitive adhesives of Examples 1 to 12 and Comparative Examples 1 to 7 prepared in (1) above were bonded to a support made of a polyurethane film to prepare pressure-sensitive adhesive sheets.
In accordance with the following method, the water absorption rate of the adhesive sheet produced using the adhesive which concerns on Examples 1-12 and Comparative Examples 1-7 and the adhesive sheet of Comparative Examples 8-10 was measured.

  Three test pieces each having a diameter of 30 mm were prepared from each pressure-sensitive adhesive sheet (pressure-sensitive adhesive layer thickness of 300 to 400 μm). It was immersed in 150 ml of physiological saline (0.9% NaCl solution) at 37 ° C. The weight of each test piece was measured before immersion (after 0 minutes) and after 20, 40, and 60 minutes after immersion. Using the formula (1), the water absorption was calculated from the measured weight.

  Table 2 shows the water absorption rate of each example and each comparative example.

  As shown in Table 2, in Examples 1 to 12, the water absorption after 60 minutes was 90% or more. In contrast, Comparative Example 6 in which the content of the hydrophilic substance was less than 5% by weight and Comparative Example 1 in which the content of the polyhydric alcohol was less than 2% had remarkably low water absorption. Further, Comparative Example 2 in which the content of the hydrophilic substance exceeds 55% by weight and Comparative Example 5 in which the content of the polyhydric alcohol exceeds 45% by weight collapsed during water absorption.

(3) Measurement of water absorption achievement rate According to the following method, the water absorption achievement rate of the pressure-sensitive adhesive sheets produced using the pressure-sensitive adhesives according to Examples 1 to 12 and Comparative Examples 1 to 7 and the pressure-sensitive adhesive sheets of Comparative Examples 8 to 10 It was measured.

  Four test pieces with a diameter of 30 mm were prepared from each adhesive sheet. It was immersed in 150 ml of physiological saline (0.9% NaCl solution) at 37 ° C. The weight of the test piece before immersion (after 0 minute), after 20, 40, 60 minutes and 24 hours after immersion was measured. Using the formula (2), the water absorption achievement rate was calculated from the measured weight.

  Table 3 shows the water absorption achievement rate of each example and each comparative example.

  As shown in Table 3, in Examples 1 to 12, the water absorption achievement rate after 60 minutes was 40% or more. On the other hand, Comparative Examples 1 and 7 having a polyhydric alcohol content of less than 2% by weight had a significantly low water absorption rate. In Comparative Example 2 in which the content of the hydrophilic substance exceeds 55% by weight and Comparative Example 5 in which the content of the polyhydric alcohol exceeds 45% by weight, the water absorption achievement rate can be measured because it collapses during water absorption. There wasn't.

(4) Comparison of water absorption I
A pressure-sensitive adhesive sheet prepared by using the pressure-sensitive adhesives according to Examples 1 to 12 and Comparative Examples 1 to 7, and a pressure-sensitive adhesive sheet for Comparative Examples 8 to 11 was attached to the support side, and a test with a diameter of 30 mm was performed. Three pieces were made. The release sheet was removed without changing the support, and it was immersed in 150 ml of physiological saline (0.9% NaCl solution) at 37 ° C. The state of the test piece 24 hours after immersion was photographed and observed. The photographed results are shown in FIGS.

  As shown in FIG. 7 and FIG. 8, it was confirmed that the test pieces of Examples 1 to 12 and Comparative Examples 1 to 6 were in close contact with each other even after being immersed for 24 hours. On the other hand, Comparative Examples 7 to 11 resulted in the retention or separation of the water in which the hydrophilic component was dissolved between the support and the pressure-sensitive adhesive layer.

  From FIG. 7, FIG. 8 and Table 1, in the case where the hydrophilic substance is not swollen with the polyhydric alcohol, water in which the hydrophilic substance and the polyhydric alcohol are dissolved is retained between the support and the pressure-sensitive adhesive layer. It can be seen that the support and the pressure-sensitive adhesive layer are separated. Here, when water is stored, it becomes a hotbed of various germs and may be easily peeled off. Further, Comparative Examples 7 and 10 were separated by water absorption. This is probably because the total amount of the hydrophilic substance and the polyhydric alcohol was too large, and the phase was reversed by water absorption.

(5) Comparison of water absorption II
Comparative Examples 12 to 14 were cut into a size of 50 mm × 30 mm, a double-sided tape was attached to the support side, and attached to a stainless steel number. The release sheet was removed and immersed in physiological saline (0.9% NaCl solution) at 37 ° C. The state of the test piece 48 hours after immersion was photographed and observed. The photographed result is shown in FIG. In addition, the test piece which image | photographed and observed the state 48 hours after was 1 mm in thickness.

  Even when Comparative Examples 12 to 14 were immersed for 48 hours, no change was observed in appearance. However, as shown in FIG. 9, when the support is peeled off, it can be seen that water in which the hydrophilic component is dissolved is retained between the pressure-sensitive adhesive layer and the support. Here, there was no change in appearance because it was difficult to understand because the hydrocolloid layer was thick, and it was actually in the same state as the other comparative examples. On the other hand, in the present invention, the retention of water in which the hydrophilic component was dissolved was not recognized even when the support was peeled off (not shown).

(6) Stability test The pressure-sensitive adhesives of Examples 1 to 12 and Comparative Examples 1 to 7 prepared in (1) above were applied to a support made of a polyurethane film to prepare pressure-sensitive adhesive sheets. The sample was left in a thermostatic bath at 50 ° C., and changes in water absorption, adhesive strength, and retention strength after 5 months were examined. The higher the stability, the less the physical property value varies with time. The changes over time for the examples and comparative examples were classified according to the criteria in Table 4 below.

  The results of the stability test are shown in Table 5. Table 5 also shows the blending ratio of polyhydric alcohol / hydrophilic substance.

  As a result of comprehensive evaluation of the physical properties, it was found that when the ratio of the polyhydric alcohol to the hydrophilic substance is more than 0.85, the stability is deteriorated. This is thought to be due to a decrease in cohesive force.

(7) Measurement of light transmittance Examples 1-12 and Comparative Examples 1-10 were cut into a size of 25 mm x 40 mm and placed on a transparent glass plate having a thickness of 0.13-0.17 mm. An ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation, UV-1650PC) was used to measure the light transmittance of this sample at a wavelength of 660 nm, and this value was taken as the visible light transmittance.

  Table 6 shows the measurement results of the light transmittance.

  As shown in Table 6, it was confirmed that the light transmittance of the example as a whole was higher than that of the comparative example. In addition, it turned out that Example 1 and 7 whose sum total of a hydrophilic material and a polyhydric alcohol is 50 weight% or more becomes low in the light transmittance compared with another Example.

(8) Measurement of holding power The pressure-sensitive adhesive sheets prepared using the pressure-sensitive adhesives according to Examples 1 to 12 and Comparative Examples 1 to 7, and the pressure-sensitive adhesive sheets of Comparative Examples 8 to 10 were cut into a size of 50 mm × 25 mm. A test piece was prepared. A cloth tape (manufactured by Sekisui Chemical Co., Ltd.) was applied to the support side, and the test piece was left in an environment of 40 ° C. for 1 hour or longer.

  On the other hand, a stainless steel plate for holding power was prepared, and a light index was applied in the width direction of the test plate with # 360 water-resistant abrasive paper, and polishing was performed by uniformly applying water in the length direction until this index disappeared. After polishing, it was rinsed clean with water and the surface was wiped with ethyl acetate. After that, the sample was left in an environment of 40 ° C. for 1 hour or more like the sample.

  Along with the marked line of the stainless steel plate, each specimen from which the release paper of the affixed part is peeled off is attached so that the test piece comes in contact with an area of 25 mm × 25 mm, and the test piece is attached by reciprocating 5 times with a 2 kg roller. It was. Thereafter, it was left in an atmosphere of 40 ° C. for 20 minutes or more. And it set to the holding power test machine in the same environment, attached the weight of 500 gf, and measured time to fall to 400 minutes.

  Table 7 shows the measurement results of the holding force. In addition, the sample which was measured up to 400 minutes and did not slide down for 400 minutes or more was displayed as “400 minutes”.

  As shown in Table 7, it was confirmed that the overall holding power was significantly higher than that of the comparative example. In Examples 2 and 10, since the total amount of the hydrophilic substance and the polyhydric alcohol was low, the holding power was low.

(9) Observation of substance state Examples 1 and 3 and Comparative Example 7 and the hydrophilic substance (raw material state) were observed and photographed using a video microscope (manufactured by Keyence Corporation).

  An imaging result is shown in FIG. As shown in FIG. 10, in Examples 1 and 3, it was confirmed that the hydrophilic substance was swollen.

(10) Healing test A pressure-sensitive adhesive sheet was prepared by laminating the pressure-sensitive adhesives of Example 12 and Comparative Example 7 on a support made of a polyurethane film, and sterilized by γ rays. A full-thickness skin defect wound with a diameter of 30 mm was prepared on a 10-week-old rat, and an adhesive sheet was attached thereto. Thereafter, wound healing was confirmed over time. As a result, the rat wound with the adhesive sheet according to Example 12 healed 2.0 times faster than the adhesive sheet according to Comparative Example 7. Moreover, compared with the case where the adhesive sheet concerning the comparative example 12 is applied, it was a 1.5 times healing rate.

DESCRIPTION OF SYMBOLS 1 Adhesive 11 Hydrophobic substance 12 Hydrophilic substance 13 Polyhydric alcohol 10 Adhesive sheet 101 Support layer 102 Adhesive layer 103 Release sheet 20 Adhesive manufacturing method 21 Mixing process 22 Swelling process 200 Adhesive sheet manufacturing method 203 Sheeting process

Claims (9)

A pressure-sensitive adhesive containing a hydrophobic substance, a hydrophilic substance, and a polyhydric alcohol,
In the continuous phase formed of the hydrophobic substance, the hydrophilic substance swollen by the polyhydric alcohol is present,
A hydrophobic material comprising 3-30% by weight thermoplastic elastomer, 5-35% by weight tackifier, 1-25% by weight softener and / or 1-35% by weight liquid rubber;
5 to 55% by weight of the hydrophilic substance, 2 to 45% by weight of the polyhydric alcohol,
The adhesive whose water absorption shown by following formula (1) is 90% or more after 60 minutes.
The pressure-sensitive adhesive according to claim 1, wherein the water absorption achievement ratio represented by the following formula (2) is 40% or more after 60 minutes.
  The pressure-sensitive adhesive according to claim 1 or 2, wherein the light transmittance at a wavelength of 660 nm is 10% or more. A pressure-sensitive adhesive containing a hydrophobic substance, a hydrophilic substance, and a polyhydric alcohol,
In the continuous phase formed of the hydrophobic substance, the hydrophilic substance swollen by the polyhydric alcohol is present,
A hydrophobic material comprising 3 to 30 wt% thermoplastic elastomer, 5 to 35 wt% tackifier, 1 to 25 wt% softener and / or 1 to 35 wt% liquid rubber;
10-50% by weight of a hydrophilic substance;
2 to 35% by weight of a polyhydric alcohol. 10 to 25% by weight of a thermoplastic elastomer;
5 to 35% by weight tackifier;
2-10% by weight softener and / or 5-30% by weight liquid rubber;
20-40% by weight of a hydrophilic substance,
The pressure-sensitive adhesive according to any one of claims 1 to 4, comprising 2 to 20% by weight of a polyhydric alcohol. A pressure-sensitive adhesive sheet comprising at least a support layer and an adhesive layer provided on at least one side of the support layer,
The pressure-sensitive adhesive layer includes at least the pressure-sensitive adhesive according to any one of claims 1 to 5.   The pressure-sensitive adhesive sheet according to claim 6, which is used for wounds. A method for producing a pressure-sensitive adhesive comprising a hydrophobic substance, a hydrophilic substance, and a polyhydric alcohol,
A mixing step of mixing the hydrophobic substance and the hydrophilic substance;
A swelling step of swelling the hydrophilic substance in the mixture with the polyhydric alcohol after the mixing step;
At least
5 to 55% by weight of the hydrophilic substance, 2 to 45% by weight of the polyhydric alcohol,
Water absorption represented by the following formula (1) The production method of after 60 minutes is 90% or more adhesive.
A method for producing an adhesive sheet comprising at least a support layer and an adhesive layer provided on at least one side of the support layer,
A mixing step of mixing a hydrophobic substance and a hydrophilic substance;
A swelling step of swelling the hydrophilic substance in the mixture with the polyhydric alcohol after the mixing step;
By doing at least
5 to 55% by weight of the hydrophilic substance, 2 to 45% by weight of the polyhydric alcohol,
A pressure-sensitive adhesive having a water absorption rate represented by the following formula (1) of 90% or more after 60 minutes,
A sheet forming step of providing the pressure-sensitive adhesive on at least one side of the support layer;
The manufacturing method of the adhesive sheet which performs.