JPH1060389A - Pressure-sensitive adhesive tape for sealing bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pressure-sensitive adhesive tape which can easily perform bag sealing to give a sealed bag which can be introduced into water without removing the sealing drawstring or tape therefrom by assembling a pressure- sensitive layer, a specified film layer and a pressure-sensitive adhesive layer. SOLUTION: Most of water-soluble or -dispersible pressuresensitive adhesives are copolymers comprising an acrylic ester and a carboxylic or hydroxy monomer and are polyacrylic ester pressuresensitive adhesive components which are made water-soluble or waterdispersible by the introduction of hydrophilic groups (e.g. carboxyl (carboxylate) groups or hydroxyl groups) thereinto. They are used for layer A and layer B. Layer B being a water-soluble or -dispersible film is one soluble or dispersible in any of cold water, warm water or hot water and is prepared by molding PVA into a film. For example, a support being a water-soluble film 1, a pressure-sensitive adhesive 2 is applied to the entire surface of each side, and a release paper 3 is stuck to each surface as a protective (coated layer) to obtain a pressure-sensitive adhesive tape for bag sealing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive tape for sealing bags used for packaging laundry, dyes, agricultural chemicals and the like. More specifically, the present invention relates to a water-soluble or water-dispersible bag-sealing pressure-sensitive adhesive tape which can be used by directly putting a bag sealed with contents therein into water, warm water, a paddy field or the like.

[0002]

2. Description of the Related Art In recent years, a variety of chemicals, including agricultural chemicals, are sealed and packaged in a unit amount in a water-soluble film, and the packaged form is put into water at the time of use, and the contents are put into water together with the packaging film. A method of dissolving or dispersing has been often used. However, when the same medicine is packaged in a large number of bags in a fixed amount, the packaging seal can be automated.However, when different medicines and different quantities are packaged, heat sealing cannot be automated. It was necessary to seal the bag with a string or tape. In this case, it is necessary to remove the string or the tape before putting it in water and using it, which involves complicated operations and risks.
In addition, laundry is often put into a water-soluble laundry bag and put into water together with the bag for washing. Particularly in hospitals, etc., it is possible to put surgical gowns, sheets, etc. after surgery in a water-soluble bag, tie the mouth of the bag with a string or the like, and then put it in warm water at 60 to 80 ° C. for sterilization and washing. Is being done. In this case as well, an operation of removing the string before putting it into the warm water is necessary, which is dangerous and requires time and effort.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to easily seal a bag (blocking and sealing with the outside), without having to remove a lanyard or tape used for sealing, and put the bag into water as it is. An object of the present invention is to provide a water-soluble or water-dispersible pressure-sensitive adhesive tape which can be used as a pressure-sensitive adhesive.

[0004]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a water-soluble or water-dispersible pressure-sensitive adhesive layer (A) / a water-soluble film layer (B) composed of polyvinyl alcohol. The present inventors have found a pressure-sensitive adhesive tape for sealing bags made of a water-soluble or water-dispersible pressure-sensitive adhesive layer (C), and have completed the present invention.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The pressure-sensitive adhesive tape for sealing a bag of the present invention comprises a water-soluble or water-dispersible pressure-sensitive adhesive layer (A) / a water-soluble or water-dispersible film layer (B) composed of polyvinyl alcohol / a water-soluble or water-dispersible pressure-sensitive adhesive layer. (C) has a three-layer structure,
In some cases, it has a four-layer or five-layer structure having a coating layer (D) for protecting the pressure-sensitive adhesive layer outside at least one of the layer (A) and the layer (C).

The water-soluble or water-dispersible pressure-sensitive adhesive used for the layer (A) and the layer (C) may be a conventionally known one, and there are many commercial products. Many of these are copolymers of acrylic acid esters and monomers having a carboxyl group or a hydroxyl group.
A hydrophilic group such as a carboxyl group (a salt thereof) or a hydroxyl group is provided to make the compound water-soluble or water-dispersible.

The water-soluble or water-dispersible film of the layer (B) is a film which is dissolved or dispersed in any of cold water, hot water and hot water,
A may be referred to as A).
Here, the PVA is a saponified polymer of a vinyl ester polymer such as vinyl acetate. The water-soluble or water-dispersible film used in the present invention is usually formed by casting a PVA aqueous solution onto a hot roll. It can also be obtained by hot-melting a mixture of PVA and a plasticizer and forming an extruded film from a T-die or an inflation film. As a method of controlling the solubility of the water-soluble film in water, a cold water-soluble film, a warm water-soluble film, and a hot water-soluble film can be obtained by changing the degree of saponification of PVA. The saponification degree of PVA is 50
-100 mol% is preferable, and 70-99 mol% is more preferable. Also, in order to improve the solubility of the water-soluble film in water, a modified PVA into which a carboxyl group (the salt thereof), a sulfonic acid group (the salt thereof), a polyoxyethylene group, a quaternary ammonium base, or the like is introduced is also used. can do. Furthermore, in order to impart the form stability of the water-soluble film, a film formed by adding an inorganic filler such as clay, talc, calcium carbonate, mica, and reinforcing fibers such as glass fiber, cellulose fiber, and vinylon fiber is also used. can do. The thickness of the film used is not particularly limited, but is usually 10 to 100 μm in consideration of the strength of the tape, toughness, dissolution rate in water, and the like. Further, the film may be embossed or matted.

[0008] The pressure-sensitive adhesive tape of the present invention is produced by applying a water-soluble or water-dispersible pressure-sensitive adhesive to both sides of the water-soluble film. The coating amount of the adhesive per side 3 to 30 g / m ^2, preferably from 5 to 20 g / m ^2. Usually, the pressure-sensitive adhesive is applied to both sides of the water-soluble film, but may be applied to the film in a dot-like or block-like form in order to increase the dissolution rate or improve flexibility.

In the pressure-sensitive adhesive tape of the present invention, a coating layer (D) may be provided outside at least one of the layer (A) and the layer (C) to protect the pressure-sensitive adhesive layer. Coating layer (D)
Examples include a release paper or a release film that protects the pressure-sensitive adhesive layer and allows it to be peeled off and adhered when used. These coating layers may be provided on one side or both sides of the layer (A) and the layer (C). The pressure-sensitive adhesive tape of the present invention is a tape having the above-described configuration, and the width and length are set to appropriate widths and lengths as needed.

An example of a method for sealing a bag using the adhesive tape of the present invention will be described. As shown in FIG. 3, an adhesive tape is attached to the inside of the mouth of the bag, and the outer adhesive layer is protected with a release paper. Because the adhesive part is covered with release paper, drugs and laundry do not adhere to the adhesive part,
It can be put into a bag smoothly. After the medicine or laundry is put in the bag, the release paper is removed and the bag is sealed. The bag sealed in this way can be put into water and used as it is. The place where the adhesive tape of the present invention is set in the bag is, besides the inside of the bag, set on the outside of the bag, and after the contents are put in the bag, the mouth portion of the bag is bent inward, and the release paper is applied. The bag can also be sealed by removing and bonding.

[0011]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. Unless otherwise specified, “%” and “parts” are based on weight.

Example 1 FIG. 1 is a sectional view showing the structure of a water-soluble pressure-sensitive adhesive tape according to the present invention. The water-soluble film 1 as a substrate and a water-soluble or water-dispersible pressure-sensitive adhesive on both surfaces of the film 1 are shown. 2 is applied to the entire surface. Here, the water-soluble film is a film containing PVA having a polymerization degree of 1700 and a saponification degree of 88 mol% as a main component, and adding 15% of glycerin as a plasticizer.

Embodiment 2 FIG. 2 shows a structure in which a release paper 3 as a protective layer (coating layer) is attached to the outside of the pressure-sensitive adhesive 2 of the water-soluble pressure-sensitive adhesive tape of Example 1.

Embodiment 3 FIG. 3 shows a bag 5 in which the water-soluble adhesive tape 4 of Embodiment 2 is adhered to the inner portion of the mouth, and the outer adhesive layer is protected by a release paper and set. The bag is a modified PVA having an itaconic acid content of 2 mol%, a polymerization degree of 1700 and a saponification degree of 88 mol%.
Is a water-soluble film obtained by adding 15% of glycerin as a plasticizer. The disperse dye was put into this bag (15 cm wide, 20 cm long), the release paper was removed, and the mouth of the bag was adhered. The adhesion at the mouth of the bag was good, and the dye in the bag did not leak out. The bag in which this dye was packaged could be used as it is by putting it into the water of the dyeing process.

[0015]

The adhesive tape of the present invention is suitable for sealing laundry bags and bags used for packaging dyes, agricultural chemicals and the like. Since the pressure-sensitive adhesive tape is water-soluble or water-dispersible, it is possible to use a bag sealed and packed in water, warm water, a paddy field, or the like as it is, and to use a string around the mouth. There is no risk of contact with dangerous drugs when removing.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a structure of a water-soluble pressure-sensitive adhesive tape having a three-layer structure.

FIG. 2 is a sectional view of a structure of a water-soluble pressure-sensitive adhesive tape having a five-layer structure.

FIG. 3 is a schematic diagram in which a water-soluble adhesive tape is set at a mouth portion of a bag made of a water-soluble film.

[Explanation of symbols]

 1: water-soluble film base material 2: adhesive 3: release paper 4: water-soluble adhesive tape of the present invention 5: bag made of water-soluble film

Continued on the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location B65D 33/20 B65D 33/20

Claims (2)

[Claims] 1. A water-soluble or water-dispersible pressure-sensitive adhesive layer (A) /
Water-soluble or water-dispersible film layer (B) composed of polyvinyl alcohol / water-soluble or water-dispersible pressure-sensitive adhesive layer (C)
Adhesive tape for sealing bags made of 2. The pressure-sensitive adhesive tape for sealing bags according to claim 1, further comprising a coating layer (D) for protecting the pressure-sensitive adhesive layer outside at least one of the layer (A) and the layer (C).