JPH08333549A - Antimicrobial tacky sheet - Google Patents

Abstract

PURPOSE: To obtain an antimicrobial tacky sheet useful as an antimicrobial use of materials to be packaged, e.g. foods or medicines or as antimicrobial wall paper, etc., for interior of buildings. CONSTITUTION: In this tacky sheet obtained by laminating a tacky agent layer and a release sheet onto a surface substrate, the surface substrate contains at least one kind of compound selected from zirconium phosphate having carried silver, carboxymethylcellulose silver salt, a quaternary ammonium salt of carboxymethylcellulose and phytoncide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial pressure-sensitive adhesive sheet, for example, an antibacterial pressure-sensitive adhesive used for the purpose of antibacterial property of a packaged product such as food or medicine or as an antibacterial wallpaper for interior of a building. It is about the seat.

[0002]

2. Description of the Related Art Adhesive sheets have been widely used for labels, stickers, patches, delivery slips, etc. for commercial use, office use, process control, physical distribution control, household use and the like. Explaining the general structure of this pressure-sensitive adhesive sheet, the pressure-sensitive adhesive is sandwiched between the surface base material and the release sheet, and as the surface base material, paper, foil, film or the like is used. . As the release sheet, high-density base paper such as glassine paper, clay-coated paper,
Providing a polylaminate base paper laminated with a resin film such as polyethylene on kraft paper or high-quality paper, or a coating layer consisting mainly of water-soluble polymers such as polyvinyl alcohol and starch and a pigment on kraft paper or high-quality paper. A resin-coated base paper coated with a release agent such as a silicone compound or a fluorine compound is used. As an adhesive,
A variety of rubber-based, acrylic-based, vinyl ether-based emulsion-type, solvent-type or solvent-free pressure-sensitive adhesives are used.

Among these adhesive sheets, an antibacterial adhesive sheet is an isothiocyanate ester as an antibacterial agent in the adhesive layer as proposed in JP-A-6-212276 and JP-A-6-212136. Those obtained by impregnating and holding the same have been used, but when the antibacterial property is imparted by such treatment, there is a problem in the antibacterial effect and the sustainability of the effect.

[0004]

The present invention relates to a novel antibacterial pressure-sensitive adhesive sheet, which has a high antibacterial activity when used as an antibacterial label for an article to be packaged such as foods and pharmaceuticals or as an antibacterial wallpaper for building interiors. It is an object of the present invention to provide an excellent antibacterial pressure-sensitive adhesive sheet which is effective and does not lose its antibacterial effect even after long-term use.

[0005]

[Means for Solving the Problems] A pressure-sensitive adhesive sheet comprising a surface substrate, a pressure-sensitive adhesive layer, and a release sheet laminated together, wherein the surface substrate has zirconium phosphate carrying silver, carboxymethylcellulose silver salt, and carboxymethylcellulose fourth.
An antibacterial pressure-sensitive adhesive sheet, which is a sheet containing at least one selected from a quaternary ammonium salt and phytoncide.

[0006]

The surface substrate constituting the antibacterial pressure-sensitive adhesive sheet of the present invention is not particularly limited as long as it is a sheet substrate such as one containing the above-mentioned material in the substrate or one coated on the substrate surface. However, for example, the average particle size is 0.1 to
A thermoplastic resin obtained by kneading an antibacterial agent in which silver is supported on zirconium phosphate having a range of 1.0 μm so that the antibacterial agent content ratio with respect to the thermoplastic resin is 0.1 to 3.0% by weight. Adsorbs silver by utilizing the ion exchange capacity of long-fiber non-woven fabric sheet and carboxymethyl cellulose
This carboxymethyl cellulose silver salt is mixed with cellulose pulp to make a paper sheet by a known paper machine, and a composite non-woven sheet obtained by laminating and integrating this paper sheet and a spunbonded non-woven fabric made of continuous continuous hydrophobic fibers, carboxymethyl cellulose first Examples thereof include a fiber sheet containing at least one kind of quaternary ammonium salt or carboxymethyl cellulose chlorhexidine salt, a sheet coated with microcapsules containing phytoncide, and the like. Needless to say, these sheets may have various known coating layers such as a recording layer such as a heat-sensitive recording layer, a thermal transfer receiving layer and an ink jet recording receiving layer and a pigment coating layer as long as the antibacterial function is not impaired. Absent.

The pressure-sensitive adhesive used in the antibacterial pressure-sensitive adhesive sheet of the present invention is a resin having a pressure-sensitive adhesive property such as (meth) acrylic acid ester copolymer resin, rubber-based resin, polyvinyl ether-based resin, polyurethane-based resin and the like. If,
Although not particularly limited, those obtained by adding phytoncide to these adhesive resins are preferable from the viewpoint of antibacterial property.

The phytoncide used in the present invention is
Natural tree essential oils and vinegar oils obtained by steam distillation, pressing, or various extraction methods from natural trees, branches, leaves, rhizomes, bark, fruits, etc., for example, extracted from the leaves of tea trees, oysters, mountain tea flowers, etc. Examples include wood essential oil, hinoki, cedar, pine, hiba, and wood essential oil extracted from eucalyptus trees.

The main components thereof include terpene substances such as α-pinene, β-pinene, ditenpen, ε-limonene, terpinolene, linalool, terpineol, borneol, cineol and hinokitiol, pinetrins, isothiocyanates and the like. To be

The amount of phytoncide added to the adhesive is 0.1 to 50 parts by weight, preferably 1 to 30 parts by weight, based on 100 parts by weight of the adhesive resin. By the way, the addition amount is 0.
If it is less than 1 part by weight, the antibacterial effect is small, and conversely 50
If it exceeds the weight part, the adhesive strength of the pressure-sensitive adhesive sheet is excessively reduced, which is not preferable.

It is more preferable that at least one of the above phytoncide components is encapsulated in microcapsules and added to an adhesive resin to produce an adhesive, since the antibacterial property lasts for a long time.

The microcapsules can be prepared by various known methods and are not particularly limited.
There are a coacervation method using gelatin and the like, an in-situ method using a synthetic polymer system, and an interfacial polymerization method.
In the coacervation method, oil drops are emulsified with hydrophilic nitrogen-containing compounds such as gelatin, gum arabic, casein, and albumin in water, and coacervation is caused by pH adjustment and concentration adjustment, followed by cooling and curing to produce. .

The in-situ polymerization method includes a method of using an aldehyde resin such as urea-formalin resin, melamine-formalin resin and melamine-urea-formalin resin as a capsule wall film. Generally, urea, thiourea,
At least one amine such as alkylurea, ethyleneurea, acetoguanamine, melamine, guanidine, buret, and cyanamide, and at least one kind of formalin, acetaldehyde, paraformaldehyde, hexamethylenetetramine, glutaraldehyde, glyoxal, furfural, etc. Capsules are produced using the aldehydes of 1 above, or an initial condensate obtained by condensing them.

In the interfacial polymerization method, a method of producing a polyurethane resin, a polyurea resin, a polyamide resin or the like at the extraction interface is exemplified. Generally, polyvalent isocyanate and water, polyvalent isocyanate and polyol, isothiocyanate and polyol are used. Synthetic capsules are manufactured by an interfacial polymerization method using polyvalent isocyanate and polyamine, isothiocyanate and polyamine, and the like.

Further, the phytoncide components encapsulated in the microcapsules may be used alone or in combination, and may be contained together with the non-volatile oil. The size of the microcapsules containing the phytoncide component is usually in the range of 1 to 100 μm, preferably 1 to 20 μm. Such a microcapsule effectively releases the phytoncide component by controlling the film thickness of the capsule. By the way, if the film thickness is too thick, the diffusion of the phytoncide component is hindered, and conversely if it is too thin, the diffusion is too strong, which causes a problem in the sustainability of the effect. About 10 to 30% is desirable.
The method for producing the antibacterial pressure-sensitive adhesive sheet, according to a conventional method,
A pressure-sensitive adhesive is coated on the surface of the release agent of the release sheet and dried to provide a pressure-sensitive adhesive layer, and then the surface base material is laminated to finish.

The base material of the release sheet in this case is high-density base paper such as glassine paper, clay-coated paper, kraft paper or high-quality paper such as casein, dextrin,
Starch, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose,
Polyvinyl alcohol, styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer, ethylene-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, acrylic ester copolymer and other natural or synthetic resins and pigments Emulsion type, solvent type or solvent-free release base material provided with a sealing layer containing as a main component, or polylaminated paper obtained by laminating polyethylene or the like on kraft paper or high-quality paper, or a film such as polypropylene or polyethylene terephthalate. Used is one in which a release agent layer is formed by coating a silicone resin or a fluororesin of a mold with a dry weight of about 0.05 to 3 g / m ² and then heat curing, ionizing radiation curing or the like.

As a coating device for coating the pressure-sensitive adhesive, for example, a roll coater, a knife coater, a bar coater, a die coater, a comma coater, a lip coater, a reverse gravure coater, a variogravure coater or the like is appropriately used. And the coated amount of adhesive is 5 by dry weight.
It is adjusted in the range of about 50 g / m ² . By the way, 5g
If it is less than / m ² , the adhesive performance of the resulting pressure-sensitive adhesive sheet will be insufficient, while if it exceeds 50 g / m ² , the pressure-sensitive adhesive will stick out during bonding of the pressure-sensitive adhesive sheets or cause cohesive failure during peeling. There is a risk that

[0018]

The present invention will be described in more detail with reference to the following examples, but of course the present invention is not limited thereto. Unless otherwise specified, all parts, weights, ratios, coating amounts and the like in the examples are shown by solid content weight.

Example 1 (Production of Surface Substrate) A silver nitrate aqueous solution having a solid content concentration of 2% was added to acid type carboxymethyl cellulose (trade name: Kikkolate HC, manufactured by Nichirin Chemical Co., Ltd.) having a degree of substitution of 0.42. Then, the slurry concentration was adjusted to 2.5%, and the mixture was sufficiently stirred, placed at a temperature of 25 ° C., and allowed to stand for 60 minutes. afterwards,
Drain the contents, wash thoroughly with water, and 30% with a centrifugal dehydrator
It was dehydrated to a pulp concentration of 30% to obtain a carboxymethyl cellulose silver salt having a solid content concentration of 30%. The silver content per dry total weight in this carboxymethylcellulose silver salt is
It was 1.84%. This carboxymethylcellulose silver salt was stirred for 1 minute with a household mixer to open the fibers, and then mixed with unbeaten conifer bleached kraft pulp to give a carboxymethylcellulose silver salt content of 1.1 per total dry weight.
The mixed pulp was prepared so as to be 0%, and a paper sheet having a basis weight of 95 g / m ² was produced by a laboratory handmade machine. The silver content in the obtained sheet was 0.02 per total dry weight.
%Met.

Next, the fineness is 2.5 denier and the basis weight is 12 g.
A spunbonded non-woven fabric made of polypropylene resin of 1 / m ² was prepared. The non-woven fabric was provided with a spot fusion zone having an area of 0.3 mm ² and a total area of 7 area%. A handmade paper sheet is laminated on a non-woven fabric which is continuously drawn from the winding, and this laminated body is placed on a rotary endless wire mesh (30 mesh stainless wire), and then the hole diameter is 0.1.
It is moved at a speed of 10 m / min under a high pressure water column flow device in which nozzle holes of 5 mm are arranged side by side at intervals of 1 mm, and a water pressure of 9
A columnar water flow of 0 kg / m ² was jetted to cause water entanglement to produce an antibacterial composite non-woven sheet.

(Production of Antibacterial Adhesive Sheet) Commercially available polyethylene laminate release paper (trade name: Separate 80EP
S cream, manufactured by Honshu Paper Co., Ltd.) was coated with an acrylic adhesive (trade name: Nicazole L-145, manufactured by Nippon Carbide Industry Co., Ltd.) at 20 g / m ² and dried, and then the above surface group was used. The material was attached to obtain an antibacterial pressure-sensitive adhesive sheet of the present invention.

Example 2 (Production of pressure-sensitive adhesive) An emulsion monomer mixture liquid [A] was prepared with the following composition. 2-Ethylhexyl acrylate 340
g, acrylic acid 2 g, methyl methacrylate 58 g, anionic emulsifier (trade name: Rebenol wz, manufactured by Kao Corporation) 2 g, nonionic emulsifier (trade name: Emulgen 92)
0, manufactured by Kao Corporation) 6 g and ion-exchanged water 170 g was prepared.

Next, in a 2-liter four-necked flask equipped with a stirrer, a cooler, a dropping funnel, a nitrogen suction tube, and a thermometer, 240 g of ion-exchanged water and the anionic emulsifier (trade name: Rebenol wz, Kao Corporation) 1 g), a nonionic emulsifier (trade name: Emulgen 920, manufactured by Kao Co., Ltd.), and 0.8 g of potassium persulfate were charged, the temperature was raised to 70 ° C. while substituting with nitrogen, and then the emulsion monomer mixture liquid [ 1/6 of A] was dropped. When the polymerization reaction rate reached 90%, the remaining emulsified monomer mixture liquid [A] was added dropwise over 2 hours for polymerization. After the dropping was completed, the reaction was matured at 70 ° C. for 2 hours to complete the polymerization reaction.

After aging, the contents of the flask were cooled to 30 ° C. To 100 parts by weight of this adhesive copolymer, 15 parts by weight of hinokitiol as phytoncide was added and stirred, and then a thickener, a defoaming agent, a wetting agent, etc. were added, neutralized with ammonia water, and a concentration of 55%, The pressure-sensitive adhesive coating liquid having a viscosity of 4500 cps was finished.

(Production of Antibacterial Adhesive Sheet) Commercially available polyethylene laminated release paper (trade name: Separate 80EP
S cream (manufactured by Honshu Paper Co., Ltd.), the above acrylic pressure-sensitive adhesive was applied at a rate of 25 g / m ² and dried, and then the same surface base material as in Example 1 was laminated to give the antibacterial property of the present invention. An adhesive sheet was obtained.

Example 3 (Preparation of phytoncide-containing microcapsules) 4.5 parts of acid-treated gelatin is sufficiently dissolved in 115 parts of water. To this, 10 parts by weight of α-pinene, 10 parts by weight of β-pinene, and 10 parts by weight of eucalyptus oil were added and emulsified at 40 ° C. Then 4
After adding 60 parts by weight of a 10% aqueous solution of gum arabic at 0 ° C and further adding 30 parts by weight of warm water at 40 ° C, pH was adjusted with acetic acid.
It was adjusted to 4.0 and cooled to 5 ° C.

Further, 8.4 parts by weight of a 10% formalin aqueous solution was added, and then adjusted to pH 10 with sodium hydroxide and cured. The obtained microcapsule liquid is spray-dried,
Microcapsules having an average particle size of 11 μm and a wall film content of 15% were obtained.

(Production of pressure-sensitive adhesive) 25 parts by weight of microcapsules containing the above phytoncide in 100 parts by weight of the same copolymer for pressure-sensitive adhesive as in Example 2 was added and stirred, and further a thickener, a defoaming agent, and a wetting agent. Etc. were added, and the mixture was neutralized with aqueous ammonia to complete a pressure-sensitive adhesive coating solution having a concentration of 55% and a viscosity of 4000 cps.

(Production of Antibacterial Adhesive Sheet) Commercially available polyethylene laminate release paper (trade name: Separate 80EP
S cream (manufactured by Honshu Paper Co., Ltd.), the above acrylic pressure-sensitive adhesive was applied at a rate of 25 g / m ² and dried, and then the same surface base material as in Example 1 was laminated to give the antibacterial property of the present invention. An adhesive sheet was obtained.

Example 4 (Production of pressure-sensitive adhesive) In the same manner as in Example 3 except that 45 parts by weight of microcapsules containing the above phytoncide were added to 100 parts by weight of the copolymer for pressure-sensitive adhesive. It was finished as an agent coating liquid. (Production of antibacterial adhesive sheet) Commercially available polyethylene laminated release paper (trade name: Separate 80 EPS cream,
Honshu Paper Co., Ltd.) with the above acrylic adhesive 25
After coating and drying so as to be g / m ² , the same surface base material as in Example 1 was attached to obtain an antibacterial pressure-sensitive adhesive sheet of the present invention.

Example 5 (Production of Surface Substrate) 15 parts by weight of pulp powder, microcapsule liquid containing phytoncide obtained in Example 3 and acrylic acid ester-acrylic acid copolymer (average degree of polymerization: 300 to 400) ) 10 parts by weight was added to obtain a capsule coating liquid.

The above capsule coating liquid was applied to a wood free paper having a basis weight of 64 g / m ^{2 by} an air knife coater so that the dry weight was 4 g / m ^2, and dried to obtain a surface base material.

(Production of Antibacterial Adhesive Sheet) An antibacterial adhesive sheet of the present invention was obtained in the same manner as in Example 3 except that the above surface substrate was laminated.

Example 6 (Production of Surface Substrate) An antibacterial agent in which zirconium phosphate having an average particle size of 0.9 μm and silver supported on a polypropylene resin having a melt flow rate of 50 was kneaded at 25% to prepare an antibacterial agent master. Batch pellets were made. Further, the masterbatch pellets were diluted with polypropylene in which the antibacterial agent was not kneaded so that the antibacterial agent content was 0.5% by weight, and melt spinning was performed at 230 ° C. to obtain a long fiber non-woven fabric.

(Production of Antibacterial Adhesive Sheet) An antibacterial adhesive sheet of the present invention was obtained in the same manner as in Example 3 except that the above surface substrate was laminated.

Example 7 (Production of surface base material) 15% by weight of bleached softwood kraft pulp
Part, 75 parts by weight of hardwood bleached kraft pulp, Carboxyme
Chill cellulose quaternary ammonium salt (trade name: CMC
-BE, manufactured by Nichirin Chemical Co., Ltd.) 2 parts by weight, filler
Paper making with 8 parts by weight and sizing agent by paper machine
Then, apply starch with a size press coater to 1.
0 g / m ²Was applied and dried to obtain a surface base material. (Manufacture of antibacterial pressure-sensitive adhesive sheet)
The same procedure as in Example 3 was performed except that the surface substrate was attached.
An antibacterial pressure-sensitive adhesive sheet of the invention was obtained.

Comparative Example 1 (Production of Adhesive Sheet) A commercially available polyethylene laminated release paper (trade name: Separate 80 EPS cream, manufactured by Honshu Paper Co., Ltd.) was coated with an acrylic adhesive (trade name: Nikasol L-145, Nippon Carbide Industry Co., Ltd.). 2)
After coating so as to be 0 g / m ² and drying, it was attached to a fine paper substrate (trade name: WF70, manufactured by Shin Oji Paper Co., Ltd.) to obtain an adhesive sheet.

Comparative Example 2 (Production of pressure-sensitive adhesive) 2-ethylhexyl acrylate 97
An adhesive was obtained by adding 10 parts by weight of allyl isothiocyanate to 100 parts by weight of a copolymer consisting of 1% by weight and 3% by weight of acrylic acid.

(Production of Antibacterial Adhesive Sheet) Commercially available polyethylene laminated release paper (trade name: Separate 80EP
S cream, manufactured by Honshu Paper Co., Ltd.), the acrylic adhesive was applied at 20 g / m ² and dried, and then a fine paper base material (trade name: WF70, manufactured by Shin Oji Paper Co., Ltd.) It stuck together and obtained the adhesive sheet.

The antibacterial pressure-sensitive adhesive sheet thus obtained was evaluated as follows, and the results are shown in Table 1.

<Evaluation Items> [Adhesive Strength] The adhesive strength to the stainless steel plate was measured according to the method for measuring the normal adhesive strength of JISZ-0237 (unit: g / 25 mm).

[Test Method for Antibacterial Property] The strain to be tested is a bacterium species that is often used for testing textile products and exists under a general environment. Klebsiella pneumoniae is a typical Gram-negative bacterium. (Klebsiella pneumoni
ae IF012732) and typical Gram-positive bacteria, Staphylococcus
aureus IF012732) was used.

For the pre-culture, a normal broth medium is used as the medium.
Normal agar medium was used for the main culture. The composition of each medium is as shown below. (Normal broth medium) Meat extract 5 g Peptone 10 g Sodium chloride 5 g Distilled water 1000 ml pH 7.0 (ordinary agar medium) Meat extract 5 g Peptone 10 g Sodium chloride 5 g Agar 15 g Distilled water 1000 ml pH 7.0

The test procedure was as follows: First, the test strain was cultivated in normal broth medium at 37 ° C. for 24 hours, and the culture solution was sterilized with high-pressure steam to give a bacterial concentration of 1
A test bacterial solution diluted to 0 ⁴ cells / ml was prepared.

Add 75 ml of this solution to an Erlenmeyer flask,
Next, the dry weight was sterilized by heating at 160 ° C for 2 hours.
An adhesive sheet (test piece) of 0 g was put. Then, this Erlenmeyer flask was placed on a shaker to obtain 340 r.p.m. p. m. , 2
The test pieces were sufficiently contacted with the bacteria in the bacterial solution by shaking at 8 ° C for 60 minutes.

Next, 10-fold dilution series from 10 times to 100,000 times of the bacterial solution was prepared, and 1 m of bacterial solution of each concentration was prepared.
1 and 15 ml of normal agar medium were used to make plates by the pour method. After culturing in a 37 ° C incubator for 48 hours,
The number of colonies was counted, and the sterilization rate against the number of bacteria before contact was calculated to evaluate the antibacterial property. Sterilization rate (%) = (Number of bacteria before contact-Number of bacteria after contact) / Number of bacteria before contact x 100 The higher the sterilization rate, the stronger the antibacterial property, but the sterilization rate is 65% or more. It can be said that it has antibacterial properties. In addition, two types of test pieces (adhesive sheets) were used in order to judge the durability of antibacterial property: one immediately after production (initial value) and one left for 3 months (after 3 months).

[Comprehensive Evaluation] The performance of the antibacterial pressure-sensitive adhesive sheet of the present invention was evaluated by combining the above evaluations. ⊚: The adhesive performance and antibacterial property were very excellent. ◯: The adhesive performance and antibacterial property were excellent. Δ: Adhesive performance or antibacterial property was slightly inferior, but there was no problem in practical use. X: Poor practicality due to poor adhesion performance or antibacterial property.

[0048]

[Table 1]

As is clear from the results shown in Table 1, the antibacterial pressure-sensitive adhesive sheet of the present invention has a high antibacterial effect and is an excellent antibacterial pressure-sensitive adhesive sheet which does not lose its antibacterial effect even after long-term use. In particular, it can be seen that the one in which the phytoncide component is contained in the pressure-sensitive adhesive layer and the one in which the phytoncide component is contained in the microcapsules are extremely excellent antibacterial pressure-sensitive adhesive sheets.

[0050]

INDUSTRIAL APPLICABILITY The antibacterial pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet exhibiting excellent antibacterial properties when used as a packaging for foods, pharmaceuticals, etc. or as a wallpaper for building interiors.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area A01N 59/16 A01N 59/16 A C09J 7/04 JHV C09J 7/04 JHV

Claims (3)

[Claims] 1. A pressure-sensitive adhesive sheet comprising a surface base material, a pressure-sensitive adhesive layer, and a release sheet laminated together, wherein the surface base material carries zirconium phosphate carrying silver, carboxymethylcellulose silver salt, and carboxymethylcellulose quaternary ammonium salt. An antibacterial pressure-sensitive adhesive sheet, which is a sheet containing at least one selected from Phytoncide. 2. The antibacterial pressure-sensitive adhesive sheet according to claim 1, wherein the pressure-sensitive adhesive layer contains a phytoncide component in the pressure-sensitive adhesive. 3. The antibacterial pressure-sensitive adhesive sheet according to claim 1, wherein the phytoncide component is encapsulated in microcapsules.