JP5982279B2 - Sheet agent - Google Patents

Description

  The present invention relates to a sheet agent.

2. Description of the Related Art Conventionally, as a sheet agent to be used by being attached to the body, one containing a hydrous gel layer containing various medicinal ingredients has been developed. If such a sheet is affixed to the skin, effects such as a skin beautifying effect, a blood circulation promoting action, an anti-inflammatory analgesic action, an antipruritic action, etc. can be brought about while giving moisture to the skin application site.
In such a sheet agent, only the hydrogel layer has low shape retention as a sheet agent and tends to be inferior in stickiness, so that an extremely thin film layer is laminated with a peelable backing layer to give rigidity. What laminated | stacked with the hydrogel layer by using a planar base material as a support body is known. Such a sheet agent is used by improving only the adhesion to the skin by peeling only the backing layer of the support at the time of use and sticking it as a flexible sheet only of the hydrogel layer and the ultrathin film. .

In this way, in order to peel only the backing layer of the support during use, the adhesive strength between the backing layer and the ultrathin film layer is adjusted in advance to a peelable range. It has been studied to perform pretreatment for improving the above (Patent Document 1).
In addition, it has been studied that a peeling starting point such as a notch or a knob is formed on the backing layer in advance (Patent Document 2).

JP 2012-140327 A JP 62-77314 A

However, in the method of Patent Document 1, it is difficult to stably adjust the adhesive strength, and only the backing layer of the support may be peeled off during the production of the gel sheet.
Further, in the method of Patent Document 2, processing and forming the separation starting point complicates the manufacturing process and leads to high costs.
The present invention relates to a sheet agent that does not require a complicated process for the backing layer serving as a support for the gel sheet agent, and can easily peel only the backing layer during use.

  The inventors use a specific polyvinyl alcohol copolymer for the backing layer to be a support for the gel sheet agent, laminate a moisture-impermeable layer on one side of the backing layer, and further laminate a hydrogel layer in the same direction. By sealing the sheet material in a packaging container, the polyvinyl alcohol copolymer absorbs the moisture evaporated from the hydrogel in the container, and it shrinks and deforms three-dimensionally, resulting in three-dimensional wrinkles and peeling off the backing layer We found that the starting point is self-forming. Furthermore, it has been found that the adhesive strength between the backing layer and the hardly moisture-permeable layer can be reduced to a peelable range, and only the backing layer of the support can be easily peeled during use.

The present invention is a sheet agent stored in a packaging container, the sheet agent is formed by laminating a support (A) and a hydrogel layer (B),
The support (A) is
(A1) a backing layer composed of a polyvinyl alcohol copolymer having a disintegration time in still water of 5 ° C. of 30 seconds or more according to the following measurement method;
(A2) layered with a moisture-impermeable layer,
The hydrogel layer (B)
The present invention relates to a sheet agent formed by laminating on a surface opposite to the surface on which the backing layer of the moisture-impermeable layer (A2) is provided.
(Measurement method of decay time)
(1) A strip test piece (width 30 mm, length 60 mm) of a backing layer (single layer) is prepared, and one end thereof is fixed.
(2) The part from the other end of the strip test piece with one end fixed to a length of 30 mm is immersed in 5 ° C. still water and held.
(3) When the strip test piece is pulled up from still water, (i) The soaked part is not dissolved in still water, or (ii) Immediately after being pulled up, the test piece falls off from the non-immersed part of the test piece. The case is defined as “collapse”, and the shortest immersion time during which the test piece “collapses” is defined as “collapse time”.

  In the packaging container of the present invention, in the packaging container, the moisture evaporated from the hydrogel is absorbed by the polyvinyl alcohol copolymer of the backing layer, and sterically contracted to form a three-dimensional crease in the backing layer. Since the peeling starting point is self-formed and the adhesive strength between the backing layer and the moisture-impermeable layer is lowered to a peelable range, only the backing layer of the support can be more easily peeled off during use. Further, the backing layer of the sheet agent has no stickiness and can be easily taken out from the packaging container.

In this invention, it is a figure which shows the method of measuring the disintegration time in 5 degreeC still water about the polyvinyl alcohol copolymer used for a backing layer. In this invention, it is a figure which shows the method of measuring delamination force (X). In this invention, it is a figure which shows the method of measuring delamination force (Y).

The sheet agent of the present invention is formed by laminating a support (A) and a hydrogel layer (B), and the support (A)
(A1) a backing layer composed of a polyvinyl alcohol copolymer having a disintegration time in 5 ° C. still water of 30 seconds or more;
(A2) It is formed by laminating a moisture-impermeable layer.
The polyvinyl alcohol copolymer used as the backing layer has a disintegration time in 5 ° C. still water of 30 seconds or more, preferably 90 seconds or more, according to the following measurement method (see FIG. 1).
(Measurement method of decay time)
(1) A strip test piece (width 30 mm, length 60 mm) of a backing layer (single layer) is prepared, and one end thereof is fixed (FIG. A).
(2) The part from the other end of the strip test piece with one end fixed to a length of 30 mm is immersed in 5 ° C. still water and held (FIG. B).
(3) When the strip specimen is pulled up from still water (Fig. C), (i) The soaked part is not dissolved in still water, or (ii) Immediately after pulling up, The case of cutting and dropping (Fig. D) is referred to as “collapse”, and the shortest immersion time during which the test piece “collapses” is defined as “collapse time”.

[Support A]
[Backing layer (A1)]
The backing layer (A1) is composed of a polyvinyl alcohol copolymer. Polyvinyl alcohol copolymer includes polyvinyl alcohol (PVA); PVA derivatives such as acetoacetalized PVA and butyral PVA; anion-modified PVA such as carboxylated PVA and sulfonated PVA, cation modification with addition of quaternary ammonium base, etc. PVA modified products such as PVA; ethylene / vinyl alcohol copolymer, vinyl alcohol / vinyl alkyl ether copolymer, vinyl alcohol / allyl alcohol copolymer and the like are included. Among these, polyvinyl alcohol is preferable from the viewpoint of being industrially easily available at a relatively low price, and a material that is hardly soluble in cold water is more preferable.

The backing layer (A1) composed of such a polyvinyl alcohol copolymer may be any film, woven fabric, non-woven fabric or the like. The thickness of the backing layer is preferably 10 μm or more and 2 mm or less from the viewpoint that appropriate rigidity can be imparted to the support (A).
When the backing layer is a film, the thickness is preferably 10 μm or more, more preferably 15 μm or more, further preferably 20 μm or more, preferably 100 μm or less, preferably 80 μm or less, and more preferably 60 μm or less. Moreover, 10 micrometers or more and 100 micrometers or less are preferable, 15 micrometers or more and 80 micrometers or less are more preferable, and 20 micrometers or more and 60 micrometers or less are still more preferable.
When the backing layer is a woven fabric or a nonwoven fabric, the thickness is preferably 0.1 mm or more, more preferably 0.3 mm or more, further preferably 0.5 mm or more, 2 mm or less, more preferably 1.5 mm or less, and 1 mm or less. Further preferred. Moreover, 0.1 mm or more and 2 mm or less are preferable, 0.3 mm or more and 1.5 mm or less are more preferable, and 0.5 mm or more and 1 mm or less are still more preferable.
Further, woven fabric, case of the nonwoven fabric, the basis weight, 5 g / m ² or more, more preferably 10 g / m ² or more, 30 g / m ² or more, and preferably 150 g / m ² or less, 100 g / m ² or less is more preferable, and 70 g / m ² or less is still more preferable. Further, it is preferably 5 g / m ² or more and 150 g / m ² or less, more preferably 10 g / m ² or more and 100 g / m ² or less, and further preferably 30 g / m ² or more and 70 g / m ² or less. The backing layer (A1) is preferably a film from the viewpoint of ease of adjustment of lamination during production and the feeling of use.

  Polyvinyl alcohol copolymers used for the backing layer (A1) include, for example, Hi-Selon M250 (Nippon Synthetic Chemical), Hi-Selon H211 (Nippon Synthetic Chemical), Sorblon EF (Icero Chemical), Sorblon NP (Icero Chemical), Hi-Selon S400 Commercially available products such as (Nippon Synthetic Chemical), Hi-Selon C200 (Nippon Synthetic Chemical), Sorblon PT (Icero Chemical), and Sorblon KA (Icero Chemical) can be used.

[Non-breathable layer (A2)]
The moisture-impermeable layer (A2) is laminated on one side of the backing layer (A1). The moisture-impermeable layer is a layer provided between the backing layer (A1) and the hydrous gel layer (B) so that moisture from the hydrogel layer (B) does not directly transfer to the backing layer (A1). Furthermore, when a sheet agent is affixed to the body, the water-containing gel layer (B) can be prevented from being excessively dried, and the mechanical strength of the water-containing gel layer (B) can be increased.
The moisture-permeable layer (A2) preferably has a water vapor permeability of 1 to 200 g / m ² · 24 Hr at 40 ° C. and a relative humidity of 90% RH as measured by a JIS Z 0208 (1976) moisture permeability test method. More preferably, it is 2-150g / m < ² > * 24Hr, More preferably, it is 5-100g / m < ² > * 24Hr.
The moisture-impermeable layer (A2) may be a single layer or a multilayer of two or more layers. In the case of a multilayer, it is sufficient that at least one layer is composed of the moisture-impermeable layer. And the moisture-containing gel layer (B) mentioned later is directly laminated | stacked on a moisture-impermeable layer.
Thus, by laminating one surface of the water-containing gel layer (B) with the moisture-impermeable layer (A2), the moisture from the water-containing gel layer (B) is applied while being applied to the body. Evaporation can be effectively suppressed to stabilize the physical properties of the hydrogel layer (B) over time, and the penetration of the medicinal components contained in the hydrogel layer (B) into the skin can be promoted.

The hydrophobic film forming the moisture-impermeable layer (A2) is a film formed from a resin having a non-polar group such as an alkyl group such as CH ₃ group or CH ₃ CH ₂ group or a benzene ring in the polymer molecule. If there is, it is not limited. Such a resin may be a homopolymer or a copolymer, such as a low density polyethylene resin, a high density polyethylene resin, an ethylene-propylene copolymer, an ethylene-butene copolymer, Polyolefin resins such as ethylene-hexene copolymer, ethylene-octene copolymer, polypropylene resin, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ionomer resin; polyethylene terephthalate, polybutylene terephthalate, polyethylene Polyester resins such as phthalates; amide resins such as nylon-6, nylon-6,6 and polymethylmethacrylamide; acrylic resins such as polymethylmethacrylate; polystyrene, styrene-acrylonitrile copolymers, Styrene / acrylonitrile resins such as tylene-acrylonitrile-butadiene copolymer and polyacrylonitrile; Hydrophobized cellulose resins such as cellulose triacetate and cellulose diacetate; Polycarbonate resins, polysulfone resins, polyethersulfone resins, polyetheretherketone Examples thereof include resins, halogen-containing resins such as polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, and Teflon (registered trademark). Among them, a resin selected from polyethylene resin, polyethylene terephthalate resin, and polypropylene resin because it can be obtained industrially at a relatively low cost, and can be processed to a very thin thickness by adjusting the T-die extrusion temperature and lamination pressure. Are preferred, polyethylene resins are more preferred, and low density polyethylene resins are more preferred.

The thickness of the moisture-impermeable layer (A2) is preferably 3 to 25 μm and more preferably 3 to 20 μm from the viewpoint of the effect of suppressing moisture evaporation and facilitating followability to the body when applied to the body.
The production method of the moisture-impermeable layer (A2) is not limited, and a normal film forming method such as a T-die casting method or an inflation method can be employed. Preferably it is an unstretched film, and it is preferable to manufacture the layer which consists of unstretched polyethylene of thickness 3-25 micrometers as a suitable one aspect | mode of a moisture-permeable layer (A2).
Examples of the moisture-impermeable layer (A2) include T.I. U. X-FC-S (Mitsui Chemicals Tosero), Toyobo Ester Film E5100 (Toyobo), CPP Film-LU02 (Santox), Suntech LD-L1850K (Asahi Kasei Chemicals), Novatec LD-LC602A (Nippon Polyethylene), Petrocene 203 (Tosoh) ), Petrocene 212 (Tosoh) and the like can be used.

[Configuration of Support A]
The support (A) is formed by laminating a backing layer (A1) and a moisture-impermeable layer (A2).
In order to laminate the backing layer (A1) and the moisture-impermeable layer (A2), it is preferable to use a T-die extrusion laminating machine. In this case, the backing layer (A1) is used as a base film, and the moisture-permeable layer (A2) is laminated while being extruded from a T-die extruder. Thereby, the moisture-permeable layer (A2) having a very thin thickness and the backing layer (A1) having higher rigidity than the layer can be laminated by a simple method. Furthermore, by adjusting the T-die extrusion temperature and laminating pressure of the resin that forms the moisture-impermeable layer (A2), the delamination strength between the moisture-impermeable layer (A2) and the backing layer (A1) can be controlled. it can. When manufactured using a T-die extrusion laminating machine, the T-die extrusion temperature can vary depending on the properties (MFR, melting point, etc.) of the resin forming the moisture-permeable layer (A2), but is usually 250 to 350. ° C, preferably 280-340 ° C. The laminating pressure can also vary depending on the combination of the backing layer (A1) and the moisture-impermeable layer (A2), but is usually 0.01 to 0.5 MPa, preferably 0.05 to 0.4 MPa. .

In the support (A) thus obtained, the delamination force (X) between the backing layer (A1) and the hardly moisture permeable layer (A2) at the time of drying is the same as that of the backing layer (A1) at the time of producing the sheet agent. It is preferably 3 to 800 g / cm, more preferably 15 to 600 g / cm, and still more preferably 80 to 600 g / cm from the viewpoint that the moisture-permeable layer (A2) does not peel off.
The delamination force (X) is measured by the following method (see FIG. 2).
(1) As shown in FIG. 2-1, a strip test piece (width 12 mm) in which a backing layer is laminated on the moisture-impermeable layer is prepared, and the entire surface of the moisture-impermeable layer located on the lower side is measured with a METTLER balance surface. (A _{1 in} FIG. 2-2).
(2) Next, in a state where the backing layer located on the upper side is loosened, the end thereof is fixed (taped) to the lifting device (Tensilon) (B _{1 in} FIG. 2-2). A state in which the end portion of the backing layer is fixed in a slack state is shown in FIG.
(3) Then, initializes the display value of the balance to zero, 20 ° C., under 40% RH environment, increasing the pulling device in the X ₁ direction at a constant rate (300 mm / min), located on the upper side of the test piece Only peel off the backing layer.
At this time, i.e., as shown in Figure 2-4, while the transition from Figure 2-4 (a) to Figure 2-4 (b), an interlayer display values of instant balance across the 90-degree line Y ₁ The value of peel strength.
At this time, the display value of the balance is negative, but is read as a positive value.

[Hydrogel layer (B)]
The water-containing gel layer (B) used in the present invention may be any layer as long as it can stably hold water, but is formed into a water-containing gel by dissolving a water-soluble anionic polymer in water and crosslinking. A crosslinked structure of an anionic polymer is preferable from the viewpoint of moldability.
Such a crosslinked structure of an anionic polymer forms a dense network structure that becomes a basic skeleton of the hydrogel layer (B) by a crosslinking reaction of the anionic polymer with an anionic polymer, a crosslinking agent, and water. The hydrogel layer (B) formed by chemically cross-linking an anionic polymer retains a large amount of water in the network structure and swells, and therefore has appropriate elasticity, extensibility, and flexibility. Furthermore, chemically crosslinked water-containing gels are less thermoplastic than agar gels and the like, and thus exhibit stable shape retention at a wide range of operating temperatures.

Examples of the water-soluble anionic polymer include polymers having a carboxyl group, a sulfate group, and a phosphate group. Specifically, poly (meth) acrylic acids, carboxyvinyl polymers and salts thereof; anionic cellulose derivatives such as carboxymethyl cellulose and carboxyethyl cellulose and salts thereof; carrageenan, alginic acid and salts thereof, anionic starch derivatives Etc. Poly (meth) acrylic acids, carboxymethylcellulose, carrageenan, and their salts are required to obtain a water-containing gel that satisfies all of the high water retention, sufficient gel strength, and flexibility to follow the unevenness and movement of the skin. It is preferable to contain at least one selected from Furthermore, carboxymethylcellulose, sodium carboxymethylcellulose, polyacrylic acid, and sodium polyacrylate are more preferable from the viewpoint that they are easily available industrially at a relatively low cost.
Specifically, CMC Daicel 2260 (Daicel FineChem), CMC Daicel 1390 (Daicel FineChem), CMC Daicel 1190 (Daicel FineChem), H-CMC (Daicel FineChem), Serogen F-BSH-12 (Daiichi Kogyo Seiyaku), Serogen F-6HS9 (Daiichi Kogyo Seiyaku), Serogen F-BSH (Daiichi Kogyo Seiyaku), Jurimer AC-10LHP (Nippon Junyaku), Jurimer AC-10SHP (Nippon Junyaku), Aronbis SX (Nippon Junyaku), Commercial products such as Aronbis MX (Nippon Pure Chemicals) and Alonbis AHX (Nippon Pure Chemicals) can be used.

  Content of anionic polymer is 0.5-25 mass% in a hydrogel, Preferably it is 3-10 mass%. In addition, in order to improve the shape retention of the crosslinked gel by adjusting the viscosity of the uncrosslinked gel or physically entangled with the network structure of the anionic polymer, The content of the functional polymer is preferably 0.5 to 6% by mass in the hydrogel.

As a crosslinking agent, a metal ion compound, a cationic polymer, a polyfunctional epoxy compound, etc. can be used, and it selects suitably by the reactivity with the functional group of the anionic polymer to be used.
Examples of the metal ion compound include oxides, hydroxides and salts containing aluminum, magnesium, calcium, potassium and the like. For example, aluminum hydroxide, potassium alum, aluminum sulfate, aluminum oxide, aluminum glycinate, aluminum acetate , Aluminum lactate, aluminum stearate, hydrous aluminum silicate, aluminum metasilicate, magnesium aluminate metasilicate, magnesium chloride, magnesium stearate, calcium carbonate, calcium hydroxide, kaolin, synthetic hydrotalcite, potassium hydroxide, etc. These can be blended singly or in combination of two or more.

A polyamino acid such as polylysine can be used as the cationic polymer.
Polyfunctional epoxy compounds include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, propylene glycol diglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, sorbitan Examples include polyglycidyl ether, trimethylolpropane polyglycidyl ether, pentaerythritol polyglycidyl ether, resorcinol diglycidyl ether, neopentyl glycol diglycidyl ether, and the like. These may be used alone or in combination of two or more. it can. When carboxymethyl cellulose or a salt thereof is selected as the anionic polymer, it is preferable to use an aluminum ion compound such as magnesium aluminate metasilicate and aluminum hydroxide as a crosslinking agent.

  As content of the crosslinking agent of a water-containing gel layer (B), 0.01-10 mass% is preferable in a water-containing gel, More preferably, it is 0.05-5 mass%, More preferably, it is 0.1-2 mass%. It is.

The hydrous gel layer (B) preferably further contains an anionic surfactant. An anionic surfactant can improve the adhesiveness between a moisture-permeable layer (A2) and a water-containing gel layer (B). Further, the mass ratio of the anionic surfactant to the mass of the water-containing gel layer (B) (anionic surfactant / water-containing gel layer) is 5 × 10 5 because it does not adversely affect the crosslinking reaction of the water-containing gel layer (B). ^{−6 to} 5 × 10 ⁻⁴ is preferable, 1.0 × 10 ^{−5 to} 3.0 × 10 ⁻⁴ is more preferable, and 2.0 × 10 ^{−5 to} 1.0 × 10 ⁻⁴ is more preferable. preferable.
By containing an anionic surfactant in the hydrous gel layer (B), it is possible to express appropriate adhesiveness with a hydrophobic film with low adhesiveness, and when it is applied to the body during use. In addition, it is possible to effectively prevent the moisture permeable layer (A2) and the water-containing gel layer (B) from being separated from the body due to deviation. Therefore, excellent adhesiveness can be expressed without providing other layers such as an adhesive layer and a primer layer between the moisture-impermeable layer (A2) and the water-containing gel layer (B). It is possible to simplify the manufacturing process.

  As the anionic surfactant, alkyl sulfate ester, polyoxyethylene alkyl sulfate ester, alkylbenzene sulfonic acid, alkyl phosphoric acid, polyoxyethylene alkyl ether phosphate, acylamino acid, alkyl ether carboxylic acid, fatty acid and salts thereof are preferable. Among these, alkylphosphorus has a high adhesive effect, good solubility in hydrous gel, easily functions as a surfactant even in weak acidity (pH 4.0 to 6.5), and has low skin irritation. One or more selected from acids, polyoxyethylene alkyl ether phosphoric acids, acylamino acids, alkyl ether carboxylic acids, fatty acids and salts thereof are preferred. Specifically, lauryl phosphoric acid, polyoxyethylene-lauryl ether Phosphoric acid, lauryl glutamic acid, cocoyl glutamic acid, myristoyl glutamic acid, polyoxyethylene-lauryl ether acetic acid, lauric acid, and potassium or sodium salts thereof are preferred.

  In the hydrogel layer (B), in addition to water, an anionic polymer, and a crosslinking agent, if necessary, a water-soluble polymer, a humectant, an oil agent, as long as the crosslinked state and storage stability are not adversely affected. Surfactants other than anionic surfactants, pH adjusters, medicinal ingredients, preservatives, antioxidants, ultraviolet absorbers, solubilizers, colorants, fragrances, and the like can be appropriately blended.

Examples of the humectant include glycerin, diglycerin, polyglycerin, 1,3-butylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polyoxyethylene diglyceryl ether, polyoxypropylene diglyceryl ether, methyl Examples include glucoside, polyoxyethylene methyl glucoside, erythritol, xylitol, sorbitol, mannitol, maltitol, trehalose and other polyhydric alcohols, sugar alcohols, saccharides, amino acids and derivatives thereof, proteins and derivatives thereof, etc. May be used singly or in combination of two or more. Since these humectants have high water retention properties, extreme drying of the water-containing gel layer (B) can be suppressed, and the flexibility for the sheet agent to follow the unevenness of the skin can be maintained.
As for content of a moisturizer, 1-55 mass% is preferable in a hydrous gel, 1-40 mass% is more preferable, 1-35 mass% is still more preferable. Since these humectants have a function as a dispersant for an anionic polymer at the time of preparing the hydrated gel, it is preferable to blend in the hydrated gel. Within this range, it is useful as a moisturizing agent or dispersant, and works in the direction of promoting dissociation of the ionic group of the anionic polymer to promote gel crosslinking. Therefore, the strength and retention of the hydrogel layer (B) are increased. This leads to improved formability.

  Examples of pH adjusters include tartaric acid, succinic acid, citric acid, lactic acid, malic acid, acetic acid, glycolic acid, hydrochloric acid, oxalic acid, phosphoric acid, sodium hydroxide, potassium hydroxide, methylamine, dimethylamine, trimethylamine, ethylamine, Diethylamine, triethylamine, propylamine, dipropylamine, tripropylamine, monomethanolamine, dimethanolamine, trimethanolamine, monoethanolamine, diethanolamine, triethanolamine, monopropanolamine, dipropanolamine, tripropanolamine, citrate Acid salts, phosphates, carbonates and the like can be mentioned. The pH of the hydrogel layer (B) is preferably adjusted to a range of 4 to 8, more preferably weakly acidic, that is, adjusted to a pH of 4.0 to 6.5. The content of the pH adjuster is preferably in the range of 0.01 to 10% by mass in the hydrogel.

  As the water of the hydrogel layer (B), natural water such as hot spring water and spring water, various water such as purified water and ion exchange water can be used. The amount of water contained when the hydrogel solution is applied is preferably 50 to 95 mass%, more preferably 55 to 90 mass%, based on the total mass of the hydrogel. Within this range, the solubility and dispersibility of water, the gelling agent and other components are good, and it is suitable for workability, that is, coating. In addition, the dispersion and solubility of the anionic polymer and other compounding bases are improved, so that the workability at the time of production is improved, and the shape retention of the formed hydrogel layer (B) is improved and uniformized. Occurs.

  The thickness of the water-containing gel layer (B) is preferably 0.5 mm or more, more preferably 0.8 mm or more, from the viewpoint that moisture is supplied from the water-containing gel layer (B) to the skin during water retention or sticking. And since it becomes easy to peel off by own weight at the time of sticking to a body, 5 mm or less is preferable and 2 mm or less is more preferable. The thickness of the hydrogel layer (B) is preferably 0.5 to 5 mm, more preferably 0.8 to 2 mm.

  The water-containing gel layer (B) is laminated on the moisture-impermeable layer (A2) of the support (A). Therefore, the hydrogel (B) is laminated on the surface opposite to the surface provided with the backing layer (A1) of the moisture-impermeable layer (A2).

[Peeling layer (C)]
The sheet agent of the present invention can be further laminated with a release layer (C). The release layer (C) (sheet, film) can be laminated on the water-containing gel layer (B), and can be laminated on the surface opposite to the support of the water-containing gel layer (B) to protect the sticking surface. The substrate of the release layer (C) (sheet, film) is not particularly limited, and examples thereof include polyester films such as polyethylene terephthalate film and polybutylene terephthalate film; polyolefin films such as polyethylene film and polypropylene film; kraft paper, glassine Examples thereof include laminated paper in which a plastic such as polyethylene is laminated on paper such as paper and fine paper. The release layer (C) is more preferably one of which one surface has been subjected to a hydrophobic treatment such as silicone treatment. The release layer (C) is laminated with the hydrogel (B) on the surface subjected to the hydrophobic treatment.
As the release layer (C), specifically, commercially available products such as Purex (Teijin DuPont), Therapy MF (Toray Film Processing), release paper (Lintec) and the like can be used.

The sheet agent of the present invention is produced by the following method.
The laminating method is not limited, and for example, the stock solution of the hydrogel layer (B) is applied on the step (1): release layer (C). Step (2): The support (A) is laminated so that the moisture-permeable layer (A2) is in contact with the hydrogel (B). Step (3): The laminate is spread using an applicator and formed into an appropriate size and shape. In some cases, the laminate is placed on a mold having the same shape. Step (4): Further, it is housed in a packaging container to be described later and left at 20 to 60 ° C. for 2 to 10 days to complete the crosslinking reaction of the hydrogel layer.

The sheet thus obtained is stored in a packaging container.
The packaging container is preferably composed of a moisture-impermeable packaging material. Examples of the packaging material include polyolefins such as polyethylene and polypropylene; plastic films such as polyester, polyvinylidene chloride, polystyrene, polyamide, and polycarbonate; Laminate films in which vapor-deposited layers such as metal aluminum, aluminum oxide, and silica are laminated on a plastic film; laminate films in which aluminum foil is laminated on the plastic film, and the like, and these single-layer films or multilayer films are also included. Can be mentioned.
Among these, a polyvinylidene chloride film, a laminate film including a polyvinylidene chloride layer, a laminate film in which a deposited layer of metal aluminum, aluminum oxide, silica or the like is laminated, and a laminate film in which an aluminum foil is laminated are preferable, and an aluminum foil is laminated. A laminate film is more preferable.
Here, the non-moisture permeability means that the water vapor permeability at 40 ° C. and relative humidity 90% RH measured by JIS Z 0208 (1976) moisture permeability test method is 0 to 100 g / m ² · 24 Hr. Preferably, it is 0-20g / m < ² > * 24Hr, More preferably, it is 0-10g / m < ² > * 24Hr.
In addition, the shape of the packaging container is not limited as long as moisture permeability is maintained, but from the viewpoint of ease of handling and cost, a packaging bag is preferable, and a pillow bag is more preferable.

  In the present invention, the support (A) and the water-containing gel layer (B) are laminated, housed in a packaging container, aged, and after completion of the crosslinking reaction of the water-containing gel layer, the sheet agent of the present invention is To completion. By the way, the sheet | seat agent accommodated in the packaging container evaporates the water | moisture content of a water-containing gel layer (B), and fills in a container. At this time, the backing layer (A1) absorbs this water vapor, swells, and shrinks and deforms three-dimensionally. As a result, a peeling start point (three-dimensional wrinkle) is self-formed in the backing layer (A1). And since the adhesive surface between the backing layer (A1) and the moisture-impermeable layer (A2) is reduced and the adhesive strength is reduced to a peelable range, only the backing layer (A1) of the support can be easily used during use. Can be peeled off. As a result, it is possible to omit any steps such as performing pretreatment for improving the peelability on the backing layer and processing and forming a peeling starting point such as a notch or a knob in the backing layer in advance. .

When the peeling start point is self-formed in the backing layer (A1), the delamination force (Y) between the backing layer (A1) and the moisture-impermeable layer (A2) of the sheet agent of the present invention is From the viewpoint that only the backing layer (A1) can be easily peeled off, it is preferably 0.3 to 3 g / cm, more preferably 0.35 to 2.5 g / cm.
In this case, the delamination force (Y) is measured by the following method (see FIG. 3).
(1) Prepare a strip test piece (width 12 mm) in which a water-containing gel layer, a moisture-impermeable layer, and a backing layer are sequentially laminated on the moisture-impermeable layer shown in FIG. The entire surface of the moisture permeable layer is fixed to the Mettler balance surface (double-sided taped) (A _{2 in} FIG. 3-2).
(2) Next, in a state where the backing layer located on the upper side is loosened, the end thereof is fixed (taped) to a lifting device (Tensilon) (B _{2 in} FIG. 3-2). FIG. 3-3 (partially enlarged view) shows a state in which the end portion of the backing layer is fixed in a slack state.
(3) Then, initializes the display value of the balance to zero, 20 ° C., under 40% RH environment, the puller at a constant rate (300 mm / min) raised to X ₂ direction, positioned on the upper side of the test piece Only peel off the backing layer.
At this time, i.e., as shown in Figure 3-4, while the transition from Figure 3-4 (a) to Figure 3-4 (b), an interlayer display values of instant balance across the 90-degree line Y ₂ The value of peel strength.
At this time, the display value of the balance is negative, but is read as a positive value.

  This invention discloses the following compositions further regarding embodiment mentioned above.

<1> A sheet agent housed in a packaging container, the sheet agent is formed by laminating a support (A) and a hydrogel layer (B),
The support (A) is
(A1) a backing layer composed of a polyvinyl alcohol copolymer having a disintegration time in still water of 5 ° C. of 30 seconds or more according to the following measurement method;
(A2) layered with a moisture-impermeable layer,
The hydrogel layer (B)
(A2) A sheet agent laminated on the surface opposite to the surface on which the backing layer of the moisture-impermeable layer is provided.
(Measurement method of decay time)
(1) A strip test piece (width 30 mm, length 60 mm) of a backing layer (single layer) is prepared, and one end thereof is fixed.
(2) The part from the other end of the strip test piece with one end fixed to a length of 30 mm is immersed in 5 ° C. still water and held.
(3) When the strip test piece is pulled up from still water, (i) The soaked part is not dissolved in still water, or (ii) Immediately after being pulled up, the test piece falls off from the non-immersed part of the test piece. The case is defined as “collapse”, and the shortest immersion time during which the test piece “collapses” is defined as “collapse time”.

<2> The sheet agent according to <1>, wherein the backing layer (A1) is preferably polyvinyl alcohol.
<3> The thickness of the backing layer (A1) is preferably 10 μm or more, more preferably 15 μm or more, further preferably 20 μm or more, preferably 100 μm or less, more preferably 80 μm or less, and further preferably 60 μm or less. The sheet agent according to 1> or <2>.
<4> The thickness of the backing layer (A1) is preferably 0.1 mm or more, more preferably 0.3 mm or more, further preferably 0.5 mm or more, preferably 2 mm or less, more preferably 1.5 mm or less, and 1 mm or less. The sheet agent according to <1> or <2>, wherein is a more preferable woven fabric or non-woven fabric.
<5> The basis weight of the backing layer (A1) is, 5 g / m ² or more, more preferably 10 g / m ² or more, 30 g / m ² or more, and preferably 150 g / m ² or less, 100 g / m The sheet agent according to <1> or <2>, wherein ² or less is more preferable, and 70 g / m ² or less is a more preferable woven or non-woven fabric.

<6> The moisture-impermeable layer (A2) is preferably selected from a polyethylene resin, a polyethylene terephthalate resin, and a polypropylene resin, more preferably a polyethylene resin, and still more preferably the low-density polyethylene resin <1>. The sheet agent of any one of-<5>.
<7> The sheet agent according to any one of <1> to <6>, wherein the moisture-permeable layer (A2) has a thickness of preferably 3 to 25 μm, more preferably 3 to 20 μm.
<8> The moisture-permeable layer (A2) has a water vapor permeability of 1 to 200 g / m ² · 24 Hr measured at 40 ° C. and a relative humidity of 90% RH as measured by a JIS Z 0208 (1976) moisture permeability test method. , more preferably, a 2~150g / m ² · 24Hr, more preferably, the are of ^{5~100g / m 2 · 24Hr <1} > ~ sheet material as claimed in any one of <7> .

<9> The sheet agent according to any one of <1> to <8>, wherein the hydrogel layer (B) is a hydrogel layer containing a crosslinked structure of an anionic polymer.
<10> The hydrogel layer (B), wherein the anionic polymer is selected from at least one selected from poly (meth) acrylic acids, carboxymethylcellulose, carrageenan and salts thereof. Any 1 sheet agent.
<11> The <9> or <10> described above, wherein the anionic polymer of the hydrogel layer (B) is selected from at least one selected from carboxymethylcellulose, sodium carboxymethylcellulose, polyacrylic acid, and sodium polyacrylate. Sheet agent.
<12> The content of the anionic polymer in the hydrogel layer (B) is preferably 0.5 to 25% by mass, more preferably 3 to 10% by mass, and any one of the above <9> to <11> The sheet agent described.

<13> The hydrogel layer (B) contains an anionic surfactant, and the mass ratio of the anionic surfactant / the hydrogel layer is preferably 5 × 10 ^{−6 to} 5 × 10 ^−4. × 10 ^-5 ~3.0 × 10 ^-4, more ^{preferably, 2.0 × 10 -5 ~1.0 × 10} -4 more preferably the <1> to sheet material as claimed in any one of <12> .
<14> The anionic surfactant contained in the hydrous gel layer (B) is selected from alkyl phosphoric acid, polyoxyethylene alkyl ether phosphoric acid, acylamino acid, alkyl ether carboxylic acid, fatty acid and salts thereof. <13> said sheet agent.
<15> The sheet according to any one of <1> to <14>, wherein the hydrogel layer (B) has a thickness of 0.5 to 5 mm.

<16> The sheet agent according to any one of <1> to <15>, wherein the release layer (C) is further laminated on the surface of the hydrogel layer (B) opposite to the support.
<17> The packaging container is made of a moisture-impermeable packaging material, and the moisture permeability measured by the test method of JIS Z 0208 has a water vapor permeability of 0 to 100 g / m ^{2 at} 40 ° C. and 90% RH. -The sheet agent of any one of said <1>-<16> with which 24Hr is preferable.
<18> The sheet agent according to any one of <1> to <17>, wherein the packaging container is a pillow bag.
<19> The sheet preparation according to any one of <1> to <17>, wherein the sheet preparation is manufactured in the following steps.
Step (1): The stock solution of the hydrogel layer (B) is applied on the release layer (C).
Step (2): The support (A) is laminated so that the moisture-permeable layer (A2) is in contact with the hydrogel (B).
Step (3): The laminate is spread and shaped.
Process (4): Furthermore, it accommodates in a packaging container.

Examples 1-7, Comparative Examples 1-4
(1) Lamination of backing layer (A1) and moisture-impermeable layer (A2):
Using the backing layer shown in Table 1 as a base film, a T-die extrusion laminator was used to extrude the heat-melted polyethylene resin from the T-die into a curtain shape, and a 5 μm-thick moisture-permeable layer ( Polyethylene resin) was laminated.

(2) Preparation of hydrous gel stock solution:
Among the compositions shown in Table 2, succinic acid and raw materials other than water were added to a kneader to prepare a slurry, and an aqueous solution in which succinic acid was dissolved in water was separately mixed and kneaded until uniform.

(3) Preparation of sheet agent:
The uncrosslinked hydrated gel stock solution obtained in (2) was applied onto a polyester film (release film: Purex U32, 50 μm) treated with silicone (only on one side), and further the backing layer (A1) and moisture permeable moisture The laminate film on which the layer (A2) was laminated was laminated so that the moisture-permeable layer was in contact with the water-containing gel, and spread using a Baker type applicator so that the gel thickness was about 1 mm. Further, after being punched into 5 cm × 5 cm square, it was sealed in a resin (having an aluminum layer as an intermediate layer) pillow and aged at 50 ° C. for 5 days to complete the crosslinking reaction of the hydrogel layer.

Test Example For the sheet materials obtained in the examples and comparative examples, the peel strength was measured by the following method, the three-dimensional crease (peeling origin) of the backing layer was formed, the backing layer was easily peeled off, and the backing layer was not sticky. In addition, the ease of taking out the sheet from the aluminum pillow was evaluated. The results are also shown in Table 1.

(1) Delamination force (X) (support only):
(1-1) As shown in FIG. 2-1, a strip test piece (width 12 mm) in which a backing layer is laminated on the moisture-impermeable layer is prepared, and the entire surface of the moisture-impermeable layer located on the lower side is measured with a METTLER. Secure to the balance surface (double-sided taped) (A _{1 in} FIG. 2-2).
(1-2) Next, in a state where the backing layer located on the upper side is loosened, its end is fixed (taped) to a lifting device (Tensilon) (B _{1 in} FIG. 2-2). A state in which the end portion of the backing layer is fixed in a slack state is shown in FIG.
(1-3) Then, initializes the display value of the balance to zero, 20 ° C., under 40% RH environment, increasing the pulling device in the X ₁ direction at a constant rate (300 mm / min), the upper from the specimen Only the backing layer located at is peeled off.
At this time, i.e., as shown in Figure 2-4, while the transition from Figure 2-4 (a) to Figure 2-4 (b), an interlayer display values of instant balance across the 90-degree line Y ₁ The value of peel strength.
At this time, the display value of the balance is negative, but is read as a positive value.

(2) Delamination force (Y) (support + hydrated gel layer):
(2-1) A strip test piece (width 12 mm) in which a moisture-containing gel layer, a moisture-impermeable layer, and a backing layer are sequentially laminated on the moisture-impermeable layer shown in FIG. The whole surface of the moisture-impermeable layer to be fixed is fixed to the METTLER balance surface (double-sided taped) (A _{2 in} FIG. 3-2).
(2-2) Next, in a state where the backing layer located on the upper side is loosened, its end is fixed (taped) to a lifting device (Tensilon) (B _{2 in} FIG. 3-2). FIG. 3-3 (partially enlarged view) shows a state in which the end portion of the backing layer is fixed in a slack state.
(2-3) Then, initializes the display value of the balance to zero, 20 ° C., under 40% RH environment, raised to X ₂ direction puller at a constant rate (300 mm / min), the upper from the specimen Only the backing layer located at is peeled off.
At this time, i.e., as shown in Figure 3-4, while the transition from Figure 3-4 (a) to Figure 3-4 (b), an interlayer display values of instant balance across the 90-degree line Y ₂ The value of peel strength.
At this time, the display value of the balance is negative, but is read as a positive value.

(3) Formation of three-dimensional wrinkle (peeling origin) of the backing layer
About the sheet | seat agent immediately after taking out from the inside of an aluminum pillow, three-dimensional flaw (peeling origin) formation of a backing layer was evaluated visually according to the following criteria.
(Double-circle): The lining layer floats locally from a moisture-permeable layer, and forms a very clear three-dimensional crease.
○: The backing layer locally floats from the moisture-impermeable layer and forms a clear three-dimensional fold.
X: The lining layer was dissolved or semi-dissolved, and no solid wrinkles were formed.

(4) Ease of peeling the backing layer:
One professional panelist evaluated the ease of peeling of the backing layer according to the following criteria for the sheet immediately after taking out from the aluminum pillow.
A: Only the backing layer can be peeled off from the moisture-impermeable layer very easily.
○: Only the backing layer can be easily peeled from the moisture-impermeable layer.
X: It is difficult to peel only the backing layer from the moisture-impermeable layer.

(5) Non-stickiness of the backing layer:
One professional panelist evaluated the non-stickiness of the backing layer according to the following criteria for the sheet material immediately after taking out from the aluminum pillow.
A: The backing layer is not sticky and easy to handle.
○: There is a little stickiness of the backing layer, but it is easy to handle.
X: The stickiness of the backing layer is very strong and difficult to handle.

(6) Ease of taking out the sheet from the aluminum pillow:
One expert panelist evaluated the ease of taking out the sheet agent from the inside of the aluminum pillow according to the following criteria.
A: The sheet agent can be taken out very easily without sticking in the pillow.
○: The sheet is difficult to stick in the pillow and can be easily taken out.
X: It is difficult for the sheet agent to stick to the pillow and take it out.

Claims (5)

A sheet agent stored in a packaging container, the sheet agent is formed by laminating a support (A) and a hydrogel layer (B);
The support (A) is
(A1) a backing layer composed of a polyvinyl alcohol copolymer having a disintegration time in still water of 5 ° C. of 30 seconds or more according to the following measurement method;
(A2) layered with a moisture-impermeable layer,
The hydrogel layer (B)
The sheet agent formed by laminating | stacking on the surface on the opposite side to the surface which provided the backing layer of the moisture-permeable layer (A2).
(Measurement method of decay time)
(1) A strip test piece (width 30 mm, length 60 mm) of a backing layer (single layer) is prepared, and one end thereof is fixed.
(2) The part from the other end of the strip test piece with one end fixed to a length of 30 mm is immersed in 5 ° C. still water and held.
(3) When the strip test piece is pulled up from still water, (i) The soaked part is not dissolved in still water, or (ii) Immediately after being pulled up, the test piece falls off from the non-immersed part of the test piece. The case is defined as “collapse”, and the shortest immersion time during which the test piece “collapses” is defined as “collapse time”.   The sheet agent according to claim 1, wherein the moisture-permeable layer (A2) is made of polyethylene.   The sheet agent according to claim 1 or 2, wherein the moisture-permeable layer (A2) has a thickness of 3 to 25 µm.   The sheet agent according to any one of claims 1 to 3, wherein the hydrogel layer (B) is a hydrogel layer containing a crosslinked structure of an anionic polymer. It is a sheet | seat agent of any one of the said Claims 1-4 accommodated in the packaging container, Comprising: The manufacturing method of the sheet agent by which this sheet agent is manufactured at the following processes.
Step (1): The stock solution of the hydrogel layer (B) is applied on the release layer (C).
Step (2): The support (A) is laminated so that the moisture-permeable layer (A2) is in contact with the hydrogel (B).
Step (3): The laminate is spread and shaped.
Process (4): Furthermore, it accommodates in a packaging container.