JPH0551069A - Bag body for cushioning - Google Patents

Abstract

PURPOSE:To provide a bag body for cushioning which is decomposed in the last even when it is discarded by a method wherein for a bag body to enclose a gas airtightly, which gives cushioning reaction to the external pressure, the bag body is formed of a decomposable material. CONSTITUTION:The bag body for cushioning 1 has a bag body 11 which is formed into a balloon shape so as to enclose a gas A, and is generally formed by blow molding, etc., and the bag body 11 is formed of a decomposable material. The decomposable material is formed of a decomposable plastic, especially a polyolefin resin such as decomposable polyethylene resin or decomposable polypropylene, etc., polyvinyl alcohol or decomposable polyester. The decomposable polyolefin resin's major component is polyolefin, and it is a resin which can be decomposed by light or microbe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cushioning material that is stored in a shoe in order to temporarily maintain the shape of a shoe or as a cushioning material when a fragile article is packaged and transported. Regarding bag body.

[0002]

2. Description of the Related Art In recent years, plastic products are glass bottles,
Demand is growing more and more because it is lighter, stronger, convenient to transport and store, and cheaper than cans.

[0003] As one of such plastic products, there is a bag body which contains a gas in a hermetically sealed manner and exerts a cushioning action against external pressure. This is, for example, temporarily stored in the shoe in order to temporarily maintain the shape of the shoe, and eventually discarded.

[0004] Regarding the post-use treatment of plastics including such a bag body, conventionally, there is no choice but to rely on incineration or landfill, and plastic waste treatment is now being highlighted as a major social problem. That is,
The incineration process requires a high-heat resistant furnace that can withstand a large amount of waste energy for combustion, resulting in a high treatment cost. Further, in the landfill process, the plastic material is not decomposed and remains in the ground as it is, so that the ground of the landfill site is not stable. Further, since the plastic material scattered on the ground is not decomposable, it remains as dust semipermanently, which poses a problem of damaging the environment.

[0005]

SUMMARY OF THE INVENTION The present invention was devised in order to solve such problems, and an object thereof is to provide a cushioning bag body having degradability.

[0006]

In order to solve the above-mentioned problems, the present invention is a bag body which encloses a gas in a sealed manner and exerts a buffering action against an external pressure, the bag body being a decomposable material. Configured to consist of.

[0007]

Since the buffer bag of the present invention is made of a decomposable material, it eventually decomposes naturally even if it is disposed of.

[0008]

Embodiments of the present invention will be specifically described below with reference to FIG. In the embodiment, a cushioning bag that is temporarily stored in shoes will be described as an example.

The cushioning bag body 1 of the present invention is a bag body 1 formed in a balloon shape so as to seal the gas A as shown in the figure.
Has 1. The thickness of the bag body 11 is of a degree, and is generally formed by blow molding or the like. Such a bag body 11
Are formed from degradable materials.

The decomposable material is formed of degradable plastics, particularly polyolefin resin such as degradable polyethylene resin or degradable polypropylene, polyvinyl alcohol or degradable polyester. The degradable polyolefin resin is a resin that contains polyolefin as a main component and can be decomposed by light or microorganisms.

Among the decomposable polyolefin resins, examples of photodegradable ones include copolymers of ethylene and carbon monoxide. This ethylene / carbon monoxide copolymer is said to be decomposed by photocleavage between the second and third carbons bonded to the carbonyl group. The decomposition rate can be controlled by the content of carbon monoxide in the copolymer. Usually, the density of ethylene / carbon monoxide copolymer is about 0.89 to 0.95 g / cm ³ , and the content of carbon monoxide is about 0.1 to 10 mol%.

The ethylene / carbon monoxide copolymer as described above is obtained by, for example, adding ethylene and carbon monoxide at a temperature of 230 ° C.
It can be manufactured by coexisting under a pressure of about 2000 atm.

As a photodegradable decomposable polyolefin resin, polyethylene (density 0.870 to 0.950) is used.
g / cm ³ , melting index (MFI) 0.4 to 40) and polypropylene (density 0.88 to 0.91 g / cm ³ , MFI
It is also possible to use a mixture of 0.2 to 50) and an organic acid metal salt. Examples of organic acid metal salts include iron stearate, cerium stearate, and cobalt stearate.
Examples thereof include metal oxides such as iron oxide, and the amount of the organic acid metal salt mixed is preferably about 1 to 5000 ppm. Further, a copolymer with vinyl ketone may be added in some cases.

Among the decomposable polyolefin resins,
Examples of the biodegradable ones include a mixture of polyolefin, polycaprolactone, starch, polyester polymerized by microorganisms, and the like.

The polyethylene used for the biodegradable polyolefin resin has a density of 0.900 to 0.950 g.
/ Cm ³ , a homopolymer of ethylene having a melting index (MI) of 0.4 to 40, or propylene, hexene, octene,
Random or block copolymers with other olefins such as 4-methylpentene-1 and further ethylenic groups such as vinyl acetate, acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, maleic anhydride, etc. Examples thereof include a copolymer with an unsaturated group-containing monomer, polypropylene, a copolymer of propylene and ethylene, and butene.

The polycaprolactone used for the biodegradable polyolefin resin is obtained by ring-opening polymerization of ε-caprolactone, and its weight average molecular weight (Mw) is
Usually, it is about 40,000 to 100,000. Starch is a polymer of D-glucose, which is industrially produced from stems and roots of potato, sweet potato, corn, wheat, etc., and its weight average molecular weight (Mw) depends on the raw material and production method. It varies from ten thousand to tens of millions. The average particle size of such starch is preferably 10 μm or less.

As the polyester polymerized by the microorganism used in the biodegradable polyolefin resin, a random copolyester of 3-hydroxybutyrate and 3-hydroxyvalerate (for example, hydrogen bacteria produced by ICI, UK) is used. And those obtained by supplying valeric acid to hydrogen bacteria, and polyesters mainly composed of 3-hydroxybutyrate.

The amount of polycaprolactone, starch and polyester polymerized by microorganisms in the biodegradable polyolefin resin as described above is 5 to 80% by weight, based on 100% by weight of the total amount of polyethylene and each of the mixed components. Is preferred. If the mixing amount of each of the above components is less than 5% by weight, the biodegradability is insufficient, and if it exceeds 80% by weight, the strength is weakened.

The polycaprolactone, the starch and the polyester polymerized by the microorganism may be used in a combination of two or more kinds. In this case, the total amount of the components mixed is 5 to 5.
It may be in the range of 80% by weight.

By using the above-mentioned photodegradable polyolefin resin as a raw material for the microbial degradable polyolefin resin, a degradable polyolefin resin having both photodegradability and microbial degradability can be obtained.

Examples of the degradable polyester include the polycaprolactone described above and a random copolymerized polyester of 3-hydroxybutyrate and 3-hydroxyvalerate which are polymerized by a microorganism. Also, vinyl alcohol is
Those having a molecular weight of about 5,000 to 100,000 and a saponification degree of 99 mol% or more are preferable.

It should be noted that such decomposable resin contains calcium carbonate, magnesium carbonate,
Metal salts such as calcium sulfate, calcium sulfite, barium sulfate and magnesium sulfate, silicic acid or kaolin,
A silicate such as talc, a metal oxide such as titanium oxide and zinc oxide, and an inorganic filler such as aluminum hydroxide and an aluminum compound such as alumina may be contained. Further, various additives such as an antioxidant, a decomposition accelerator, a stabilizer, an antistatic agent and a surfactant may be contained.

The bag body 11 as described above is generally formed by blow molding as described above.
It may be formed using various known molding methods.

[0024]

Since the cushioning bag of the present invention is made of a decomposable material, it has the effect of finally decomposing even if it is disposed of.

[Brief description of drawings]

FIG. 1 is a perspective view of a cushioning bag body of the present invention.

[Explanation of symbols]

 1 ... Buffer bag 11 ... Bag body

Claims (1)

[Claims] 1. A cushioning bag body which encloses gas in a sealed manner and exerts a cushioning action against external pressure, wherein the bag body is made of a decomposable material.