JPH07286147A - Biodegradable tacky tape or sheet - Google Patents

Abstract

PURPOSE:To obtain a biodegradable tacky tape or sheet decomposable in soil or in water with a microorganism free from environmental pollution, by providing one side of a biodegradable substrate with a specific biodegradable aliphatic polyester layer and coating the other side of the substrate with a biodegradable tacky agent. CONSTITUTION:(A) One side of a biodegradable substrate is provided with (B) a biodegradable aliphatic polyester layer consisting essentially of an aliphatic polyester having >=10,000 number-average molecular weight {e.g. a polyester of the formula [R<1> and R<2> are each 2-10C (cyclo)alkylene, etc.; R<3> is a polyisocyanate residue; M>= 0; (m) is degree of polymerization] obtained by reacting an OH terminal aliphatic polyester polyol which is prepared by dehydrating a (cyclic) aliphatic glycol and a (cyclic) aliphatic dicarboxylic acid (anhydride) as main components and subjecting to the resultant substance to glycol removal reaction with a polyisocyanate, the top of the biodegradable aliphatic polyester layer is optionally furnished with a release layer and the other side of the substrate A is coated with (C) a biodegradable tacky agent to give the objective tape or sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cloth adhesive tape or sheet which is decomposed by microorganisms in soil or water and does not pollute the environment.

[0002]

2. Description of the Related Art Adhesive tapes prepared by applying an adhesive to various base materials have various excellent properties and have been widely used by industry and general consumers. There is. However, the adhesive product is, by its nature, almost impossible to collect and dispose of, and there is a risk that the adhesive product will stop its original shape for a long time and pollute the environment when it is left outdoors. As a method of coping with this, a product soluble in water or an alkaline aqueous solution is prepared (Japanese Patent Laid-Open No. 61-246239
No. 1, JP-A-1-165685, etc.), using a substrate containing a biological substance such as collagen (JP-A No. 62-22880), and using a biodegradable substrate coated with rubber or the like. (JP-A-4
-220478) is proposed. Adhesive tapes coated with a water-soluble adhesive on a paper base have already been put to practical use, but adhesive products have a wide range of fields of use and the characteristics required for each product differ, so generally, excellent adhesive There is nothing that combines both properties and rapid degradability after use and disposal, and efforts have been made to create degradable adhesive products.

[0003]

Adhesive products based on elastomers such as natural rubber are flexible and can be applied thickly, so they easily adhere to rough surfaces and are a unique Japanese adhesive tape packaging. Widely used as cloth adhesive tape. The cloth adhesive tape is formed by coating a base material provided with a layer such as polyolefin on a cloth with an adhesive agent based on an elastomer such as natural rubber, and when the cloth adhesive tape is left in the natural world, The natural product-derived material decomposes and disappears over time, but the natural decomposition of the non-natural product material is not easy, and in particular, the polyolefin layer and the like remain without decomposition. Nowadays, environmental pollution is advancing rapidly, and there is a strong demand for an adhesive product that has excellent adhesive properties when used and has a property of rapidly decomposing after use even if it is discarded in Yamano.

An object of the present invention is to solve the above problems of the prior art and to provide a cloth adhesive tape or sheet which is decomposed by microorganisms in soil or water and does not pollute the environment. It is in.

[0005]

[Means for Solving the Problems] The above object is to provide a base material comprising a biodegradable substance such as a cellulose fiber with a biodegradable aliphatic polyester layer having characteristics equivalent to those of a polyolefin or the like on a base material. This can be achieved by using a pressure-sensitive adhesive sheet or pressure-sensitive adhesive tape coated with a biodegradable pressure-sensitive adhesive based on an elastomer such as natural rubber to which acceleration is imparted.

More specifically, (1) an aliphatic (including cycloaliphatic) glycol and (2) an aliphatic (including cycloaliphatic) dicarboxylic acid (or the Acid anhydride) as the main component, a small amount of (3) trihydric or higher polyhydric alcohol, polyhydric oxycarboxylic acid (or its acid anhydride),
Or trivalent or higher polycarboxylic acid (or its acid anhydride)
Aliphatic polyester having a number average molecular weight of 10,000 or more obtained by reacting a polyfunctional isocyanate with an aliphatic polyester polyol having a hydroxyl group terminal, which is obtained by a dehydration reaction and a deglycolization reaction in the presence or absence of A biodegradable aliphatic polyester layer containing (A) as a main component is provided, a release layer is formed on the upper surface thereof as required, and a biodegradable adhesive is applied to the other surface of the base material. A biodegradable cloth adhesive tape or sheet characterized by that, or on one side of the biodegradable cloth substrate, (1)
Aliphatic (including cycloaliphatic) glycol and (2) aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) as a main component, a small amount (3) trihydric or higher polyhydric alcohol ,
An ester reaction is carried out in the presence or absence of a polyhydric oxycarboxylic acid (or an acid anhydride thereof) or a polyvalent carboxylic acid having a valence of 3 or more (or an acid anhydride thereof), and the produced polyester polyol is allowed to react with Below 180-230 ℃ temperature and
Aliphatic polyester with a number average molecular weight of 10,000 or more obtained by deglycolization under high vacuum of 0.005 to 1 mmHg
A biodegradable aliphatic polyester layer containing (B) as a main component is provided, a release layer is formed on the upper surface thereof as required, and a biodegradable adhesive is applied to the other surface of the base material. It can be achieved by using a biodegradable cloth adhesive tape or sheet characterized by the following.

[0007]

In general, the cloth adhesive tape is formed by applying an adhesive agent based on an elastomer such as natural rubber or synthetic rubber to a base material on which a layer such as polyolefin is provided. If the adhesive tape is left in the natural world, natural rubber, which is a polymer of isoprene, and synthetic rubber elastomers containing isoprene, butadiene, etc., which have similar chemical structures as those of the copolymer, as one component of the copolymer will be decomposed by oxidation or hydrolysis. It is easy, and it is expected that the low molecular weight compound generated thereby will be finally decomposed by microorganisms. Therefore, the adhesive composition based on these elastomers has a high possibility of being biodegraded in the long term. Further, it is expected that a cloth substrate made of cellulose fibers or the like will be easily decomposed by microorganisms, but a layer of polyolefin or the like provided on the cloth substrate remains without being decomposed.

With respect to the pressure-sensitive adhesive, the decomposition can be promoted by adding a substance which is easily decomposed by microorganisms to the extent that the adhesive property is not impaired. When the added easily decomposable substance first decomposes and disappears, oxygen and water can easily permeate into the inside of the pressure-sensitive adhesive, and oxidation and hydrolysis rapidly proceed. This facilitates the action of microorganisms, and causes the adhesive to disintegrate and decompose rapidly.

Polyolefin and the like are extremely stable and difficult to decompose, but by substituting this with an aliphatic polyester having similar melting point, film-forming property and the like and having biodegradability, adhesive tapes as a whole are biodegraded. Can be sex. The aliphatic polyester used for this purpose contains (1) an aliphatic (including cycloaliphatic) glycol and (2) an aliphatic (including cycloaliphatic) dicarboxylic acid (or an acid anhydride thereof) as a main component. In the presence or absence of a small amount of (3) trihydric or higher polyhydric alcohol, polyhydric oxycarboxylic acid (or its acid anhydride), or trivalent or higher polyhydric carboxylic acid (or its acid anhydride). Aliphatic polyester polyol having a hydroxyl group terminal obtained by dehydration reaction and deglycolization reaction under, further obtained by reacting a polyfunctional isocyanate, the number average molecular weight of 10,000 or more aliphatic polyester of the following general formula structure (A )

[0010]

[Chemical 1]

(Where m is the number average molecular weight of the above equation is 10,00
Is a degree of polymerization required to be 0 to 100,000, M is 0 or a number of 1 or more, R ¹ and R ² are alkylene groups having 2 to 10 carbon atoms, a cycloring group or a cycloalkylene group (may be branched) ), R ³ is a di- or polyisocyanate residue. ) Alternatively, (1) an aliphatic (including cycloaliphatic) glycol
(2) Aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) as a main component, a small amount of (3) trihydric or higher polyhydric alcohol, polyhydric oxycarboxylic acid (or acid anhydride thereof) Substance), or in the presence or absence of a trivalent or higher polycarboxylic acid (or acid anhydride thereof),
180-230 in the presence of catalyst the polyester polyol produced
Some of them are mainly composed of an aliphatic polyester (B) having a number average molecular weight of 10,000 or more and having the following general structure, which is produced by carrying out a deglycolization reaction at a temperature of ° C and a high vacuum of 0.005 to 1 mmHg.

[0012]

[Chemical 2]

(Where m is the degree of polymerization required for the number average molecular weight of the above polyester to be 10,000 or more, R ¹ and R ²
Is an alkylene group having 2 to 10 carbon atoms. However, when a small amount of the above component (3) is present, branching may occur. ) When the biodegradable pressure-sensitive adhesive tape or sheet is configured as described above, the bond strength between the biodegradable base material and the biodegradable aliphatic polyester layer is set to the biodegradable aliphatic polyester layer or the biodegradable aliphatic polyester layer. It is necessary that the bond strength between the release layer formed on the layer and the biodegradable pressure-sensitive adhesive layer is larger than the bond strength.

[0014]

EXAMPLES Hereinafter, the biodegradable cloth adhesive tape or sheet of the present invention will be specifically described with reference to Examples. However,
The scope of the present invention is not limited to the contents described in the examples.

[0015]

Example 1 100 parts by weight of natural rubber, 100 parts by weight of petroleum resin,
120 parts by weight of corn starch, 30 parts by weight of liquid paraffin,
A composition consisting of 2 parts by weight of an antioxidant was kneaded with a kneader to prepare an adhesive composition (I). About 100 μm of the obtained composition on a suf cloth provided with an aliphatic polyester layer
50mm x 100mm cloth adhesive tape sample coated to the thickness of 4 liters is embedded in about 4 liters of garden soil in a stainless steel container, and water is supplied at any time under the conditions of 37 ° C and 90% RH. I left it for 6 months.

After leaving the sample for a while, the sample was taken out and examined. As a result, mold was generated on the entire cloth adhesive tape, and when it was washed with water to wash off the soil, it was broken apart.

[0017]

[Comparative Example 1] 100 parts by weight of natural rubber, 100 parts by weight of petroleum resin,
A composition comprising 200 parts by weight of calcium carbonate, 50 parts by weight of naphthenic oil, and 2 parts by weight of an antioxidant was kneaded with a kneader to prepare an adhesive composition (II). A 50 mm x 100 mm piece of cloth adhesive tape sample coated with the obtained composition on a soft cloth provided with a polyethylene layer to a thickness of about 100 µm is placed in about 4 liters of garden soil in a stainless steel container. It was filled and left for 6 months under the conditions of 37 ° C and 90% RH while supplying water as needed.

After the above-mentioned standing, the sample was taken out, washed with water and dried, and the weight change was measured. The weight loss was about 5%.
Therefore, almost no change was observed.

[0019]

As described above, by using the cloth adhesive tape or sheet as the biodegradable cloth adhesive tape or sheet of the present invention, the problems of the prior art can be solved and the soil Alternatively, it was possible to provide a cloth pressure-sensitive adhesive tape or sheet which is decomposed by microorganisms in water and does not pollute the environment.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masato Koyama, No. 3819 Noborito, Tama-ku, Kawasaki City, Kanagawa Prefecture Sliontech Co., Ltd. (72) Toru Watanabe 3-20, Kandanishikicho, Chiyoda-ku, Tokyo Showa Polymer Within

Claims (3)

[Claims] 1. A biodegradable cloth substrate having (1) an aliphatic (including cycloaliphatic) glycol and (2) an aliphatic (including cycloaliphatic) dicarboxylic acid (or an acid anhydride thereof) on one side thereof. The presence of a small amount of (3) trihydric or higher polyhydric alcohol, polyhydric oxycarboxylic acid (or its acid anhydride), or trihydric or higher polycarboxylic acid (or its acid anhydride). Obtained by dehydration reaction and deglycolization reaction in the presence or absence of
Aliphatic polyester polyol (A) having a number average molecular weight of 10,000 or more obtained by further reacting a polyfunctional isocyanate with an aliphatic polyester polyol having a hydroxyl group terminal
Provide a biodegradable aliphatic polyester layer whose main component is,
A biodegradable cloth pressure-sensitive adhesive tape or sheet, comprising a release layer formed on the upper surface of the base material if necessary, and a biodegradable pressure-sensitive adhesive applied on the other surface of the base material. 2. A (1) aliphatic (including cycloaliphatic) glycol and (2) an aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) on one side of a biodegradable cloth substrate. The presence of a small amount of (3) trihydric or higher polyhydric alcohol, polyhydric oxycarboxylic acid (or its acid anhydride), or trihydric or higher polycarboxylic acid (or its acid anhydride). The ester reaction is carried out in the presence or absence of a catalyst, and the produced polyester polyol is added in the presence of a catalyst at a temperature of 180 to 230 ° C.
A biodegradable aliphatic polyester layer mainly composed of an aliphatic polyester (B) having a number average molecular weight of 10,000 or more obtained by carrying out a deglycolization reaction under a high vacuum of mHg is provided, and a release layer is provided on the upper surface thereof if necessary. And a biodegradable pressure-sensitive adhesive applied on the other surface of the above-mentioned substrate, a biodegradable cloth pressure-sensitive adhesive tape or sheet. 3. The bond strength between the biodegradable substrate and the biodegradable aliphatic polyester layer is such that the biodegradable aliphatic polyester layer or a release layer and a biodegradable adhesive layer formed on the biodegradable aliphatic polyester layer. It is stronger than the bond strength with.
Alternatively, the biodegradable adhesive tape or sheet according to 2.