JPH08647A - Biodegradable oral cavity inside cleaning tool - Google Patents

Abstract

PURPOSE:To eliminate a problem of environmental pollution by decomposing an oral cavity inside cleaning tool using biodegradable thermoplastic resin in a short time even when it is thrown away in the ground in abandonment after the use. CONSTITUTION:In this biodegradable oral cavity inside cleaning tool which is composed of a filament and/or a product material composed of a polymer or a coploymer of one or two or more kinds selected from lactic acid, glycol acid or caprolactone and is formed of biodegradable thermoplastic synthetic resin, when a plasticizer such as citric acid ester or lactic acid ester is blended thereto, moldability is improved. A dental froth and dental froth pick are particularly preferable as the biodegradable oral cavity inside cleaning tool. Thereby, since an equipment and a metal mold in the present condition can be used, this biodegradable oral cavity inside cleaning tool can be inexpensivly produced. Since it is decomposed in a short time even when it is thrown away in the ground in abandonment after use, a problem of environmental pollution is not caused.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biodegradable oral cleaning tool made of a biodegradable thermoplastic resin which is decomposed by discarding it in the soil without discarding it after incineration. Conventionally, the oral cleaning tool, polypropylene, polyethylene, polyethylene terephthalate, an oral cleaning tool composed of a thermoplastic resin such as polybutylene terephthalate resin is used, as the filament,
Filaments made of thermoplastic resins such as nylon, polypropylene and polybutylene terephthalate have been used.

The oral cleaning tool is disposed of after use and is incinerated or disposed of in the soil. In such disposal, there is a problem that when incinerated, there is a pollution problem that carbon dioxide increases, and when it is dumped in the soil, it is not permanently decomposed and remains. These effects on the environment are major problems around the city, and an early solution is desired.

Since environmental problems have been highlighted in this way, the present invention was carried out by researching the disposal of used oral cleaning tools without adversely affecting the environment. The intraoral cleaning tool mentioned here means a tool used for cleaning the oral cavity, that is, a toothbrush, an interdental brush, a dental floss, or a dental floss pick. The dental floss pick is a generic name in which one end made of resin is sharpened to form a pick, and the other end is arcuately formed to bond the floss. These oral cleaning tools are formed of only a thermoplastic resin, or a thermoplastic resin and a small amount of metal material (brass brass, stainless steel, etc.). Of these, dental floss and dental floss pick are often used immediately after meals and are often treated with leftover food after normal use, and these two products are often composed only of a thermoplastic resin. Since the biodegradable oral cleaning tool of the present invention is wholly or almost entirely made of a biodegradable thermoplastic resin, it is decomposed in a short time even if it is thrown into the soil without incineration at the time of disposal. , Not only does not cause the environmental problems already mentioned,
Since these components are decomposed in the soil and also act as organic fertilizer, they can be positively used as fertilizer. As the thermoplastic synthetic resin having biodegradability,
A polymer or copolymer composed of one or more selected from lactic acid, glycolic acid and caprolactone is desirable. Biodegradable thermoplastic resins include starch and PV
There is also a type in which A (polyvinyl alcohol) is mixed, but it is unsuitable for the purpose of this patent application because of its low water resistance.
The polymer or copolymer comprising one or more selected from lactic acid, glycolic acid and caprolactone is
Although it can be used by itself, its physical properties can be changed by adding another resin or blending a plasticizer. By adding a plasticizer, flexibility is imparted to improve moldability. The plasticizer content is usually 1 to 25% by weight, more preferably 5 to 15% by weight. If the content is less than 1% by weight, cracking tends to occur due to lack of flexibility during molding, and if it exceeds 25% by weight, the hardness as an oral cleaning tool becomes insufficient. As these plasticizers, biodegradable ones are preferable, and citrate esters, lactate esters, etc. are used. As these esters, methyl ester, ethyl ester and propyl ester are preferable. As a method for producing an oral cavity cleaning tool using such a biodegradable resin, a general method for producing an oral cavity cleaning tool can be applied as it is. That is, in the case of a toothbrush, a handle is molded with a biodegradable resin, a monofilament spun with the biodegradable resin is flocked with a flocking machine, and the tip of the filament is trimmed and the tip of the bristle tip is rounded to obtain a toothbrush. . Most preferably, the biodegradable resin is used for both the handle and the filament, but it can be used for either the handle or the filament. In the case of an interdental brush, a spiral brush is produced by a twist flocking machine using a monofilament spun with a biodegradable resin and a metal wire. A spiral brush is inserted into a mold, and a handle is produced by insert molding using a biodegradable resin to obtain an interdental brush. As the metal wire, it is desirable to use stainless steel or an iron-based alloy that easily corrodes in the soil. The biodegradable resin is most preferably used for both the handle and the filament, but can be used for either the handle or the filament. Dental floss is produced by bobbin winding a multi-filament spun with a biodegradable resin and placing it in a container molded with the biodegradable resin. Biodegradable resin is most desirable to use for both filament and container,
It doesn't matter if you use it for either one. In the dental floss pick, a multifilament spun with a biodegradable resin is inserted into a mold, and a handle is produced by insert molding using the biodegradable resin. Then, unnecessary yarn is cut to obtain a dental floss pick. Biodegradable resin is
Most preferably it is used for both the filament and the handle, but it can also be used for either one. The filament used in the present invention preferably has a tensile strength per denier of 3 g or more. If the amount is less than 3 g, the strength may be insufficient and the durability may be poor.
These biodegradable oral cleaning tools have sufficient water resistance and durability to be used in the oral cavity, and when they are thrown into the soil, they are decomposed in the soil and cause no environmental problems.

【Example】

Example 1 A polylactic acid resin containing 12% by weight of ethyl citrate as a plasticizer was injection-molded at a resin temperature of 200 degrees Celsius using an injection molding machine with a mold clamping pressure of 140 tons, and a toothbrush handle. Got A monofilament having a tensile strength of 4 g per 1 denier spun at a draw ratio of 6 was flocked to this handle with a Tsujimura flocking machine to obtain a toothbrush. When this toothbrush was brushed for a total of 9 minutes a day, it had good durability and a feeling of use for 1 month. When this product was buried in the soil of a forest in Osaka Prefecture, it was biodegraded after 12 months. Comparative Example 1 Polyamide 6 is added to a handle made by injection molding polypropylene.
When the toothbrush with 12 filaments was buried in the soil under the same conditions as in Example 1, the appearance was not changed after 12 months and biodegradation was not observed at all. Example 2-5, Comparative Example 2-5 An intraoral cleaning tool was produced by a conventional method, and Example 1, Comparative Example 1
When the same evaluation as above was performed, the results shown in Table 1 were obtained.

[Table 1] Regarding the evaluation of the feeling of use, the results of use by 10 professional panelists were described in three levels. The biodegradability test was carried out by burying it in soil (20 cm below the ground) in a forest under Osaka prefecture and taking it out one year later and inspecting it. As a result of the inspection, A was disassembled and the original form was lost, A was a part of the original form, and B was the entire original form.

[Effect] The biodegradable oral cleaning tool according to the present invention uses the biodegradable thermoplastic resin made of a polymer or copolymer of lactic acid, glycolic acid, caprolactone, etc. Or, it can be used with only a slight modification, and can be produced at low cost. The oral cleaning tools made of these biodegradable thermoplastic resins do not cause pollution problems by being decomposed in a short time even if they are thrown into the soil without being incinerated for disposal after use.

[Procedure amendment]

[Submission date] June 27, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biodegradable oral cleaning tool made of a biodegradable thermoplastic resin which is decomposed by discarding it in the soil without discarding it after incineration. Conventionally, the oral cleaning tool, polypropylene, polyethylene, polyethylene terephthalate, an oral cleaning tool composed of a thermoplastic resin such as polybutylene terephthalate resin is used, as the filament,
Filaments made of thermoplastic resins such as nylon, polypropylene and polybutylene terephthalate have been used.

[0002]

The oral cleaning tool is disposed of after use and is incinerated or disposed of in the soil. In such disposal, there is a problem that when incinerated, there is a pollution problem that carbon dioxide increases, and when it is dumped in the soil, it is not permanently decomposed and remains. These effects on the environment are major problems around the city, and an early solution is desired.

[0003]

Since environmental problems have been highlighted in this way, the present invention was carried out by researching the disposal of used oral cleaning tools without adversely affecting the environment. The intraoral cleaning tool mentioned here means a tool used for cleaning the oral cavity, that is, a toothbrush, an interdental brush, a dental floss, or a dental floss pick. The dental floss pick is a generic name in which one end made of resin is sharpened to form a pick, and the other end is arcuately formed to bond the floss. These oral cleaning tools are formed of only a thermoplastic resin, or a thermoplastic resin and a small amount of metal material (brass brass, stainless steel, etc.). Of these, dental floss and dental floss pick are often used immediately after meals and are often treated with leftover food after normal use, and these two products are often composed only of a thermoplastic resin.

Since the biodegradable oral cleaning tool of the present invention is wholly or almost entirely made of biodegradable thermoplastic resin, it can be disposed of for a short time even if it is dumped into the soil without incineration. Not only does it not decompose and cause the environmental problems mentioned above, but it also has the effect of decomposing these components in the soil and acting as an organic fertilizer, and it can even be actively used as a fertilizer. The biodegradable thermoplastic synthetic resin is preferably a polymer or copolymer composed of one or more selected from lactic acid, glycolic acid and caprolactone. As a biodegradable thermoplastic resin, there is a type in which starch and PVA (polyvinyl alcohol) are mixed, but it is unsuitable for the purpose of this patent application because of its low water resistance.

The polymer or copolymer consisting of one or more selected from lactic acid, glycolic acid and caprolactone can be used by itself, but its physical properties can be changed by adding other resin or incorporating a plasticizer. . By adding a plasticizer, flexibility is imparted to improve moldability. The plasticizer content is usually 1 to
It is 25% by weight, but more preferably 5 to 15% by weight. If the content is less than 1% by weight, cracking tends to occur due to lack of flexibility during molding, and if it exceeds 25% by weight, the hardness as an oral cleaning tool becomes insufficient. As these plasticizers, biodegradable ones are preferable, and citrate esters, lactate esters, etc. are used. As these esters, methyl ester, ethyl ester and propyl ester are preferable.

As a method for producing an oral cavity cleaning tool using such a biodegradable resin, a usual method for producing an oral cavity cleaning tool can be applied as it is. That is, in the case of a toothbrush, a handle is molded with a biodegradable resin, a monofilament spun with the biodegradable resin is flocked with a flocking machine, and the tip of the filament is trimmed and the tip of the bristle tip is rounded to obtain a toothbrush. . Most preferably, the biodegradable resin is used for both the handle and the filament, but it can be used for either the handle or the filament.

In the case of an interdental brush, a spiral brush is produced by a twist flocking machine using a monofilament spun with a biodegradable resin and a metal wire. A spiral brush is inserted into a mold, and a handle is produced by insert molding using a biodegradable resin to obtain an interdental brush. As the metal wire, it is desirable to use stainless steel or an iron-based alloy that easily corrodes in the soil. Biodegradable resin is most desirable to use for both handle and filament,
It can also be used on either the handle or the filament.

Dental floss is produced by bobbin winding a multifilament spun with a biodegradable resin and placing it in a container molded with the biodegradable resin. The biodegradable resin is most preferably used for both the filament and the container, but it may be used for either one. In the dental floss pick, a multifilament spun with a biodegradable resin is inserted into a mold, and a handle is produced by insert molding using the biodegradable resin. Then, unnecessary yarn is cut to obtain a dental floss pick.
The biodegradable resin is most preferably used for both the filament and the handle, but can be used for either one. The filament used in the present invention preferably has a tensile strength per denier of 3 g or more. If the amount is less than 3 g, the strength may be insufficient and the durability may be poor. These biodegradable oral cleaning tools have sufficient water resistance and durability to be used in the oral cavity, and when they are thrown into the soil, they are decomposed in the soil and cause no environmental problems.

[0009]

Example 1 A polylactic acid resin containing 12% by weight of ethyl citrate as a plasticizer was injected using an injection molding machine with a mold clamping pressure of 140 tons in an 8-cylinder mold at a resin temperature of 200 degrees Celsius. Molded to obtain a toothbrush handle. A monofilament having a tensile strength of 4 g per 1 denier spun at a draw ratio of 6 was flocked to this handle with a Tsujimura flocking machine to obtain a toothbrush. When this toothbrush was brushed for a total of 9 minutes a day, it had good durability and a feeling of use for 1 month. When this product was buried in the soil of a forest in Osaka Prefecture, it was biodegraded after 12 months.

Comparative Example 1 Polyamide 6 was added to a polypropylene injection-molded handle.
When the toothbrush with 12 filaments was buried in the soil under the same conditions as in Example 1, the appearance was not changed after 12 months and biodegradation was not observed at all. Example 2-5, Comparative Example 2-5 An intraoral cleaning tool was produced by a conventional method, and Example 1, Comparative Example 1
When the same evaluation as above was performed, the results shown in Table 1 were obtained.

[0011]

[Table 1]

For the evaluation of the feeling of use, the results of use by 10 professional panelists were described in three levels. The biodegradability test is
It was buried in the soil (20 cm underground) of a forest in Osaka prefecture, and taken out one year later and inspected. As a result of the inspection, A was disassembled and the original form was lost, A was a part of the original form, and B was the entire original form.

[0013]

[Effect] The biodegradable oral cleaning tool according to the present invention uses the biodegradable thermoplastic resin made of a polymer or copolymer of lactic acid, glycolic acid, caprolactone, etc. Or, it can be used with only a slight modification, and can be produced at low cost. The oral cleaning tools made of these biodegradable thermoplastic resins do not cause pollution problems by being decomposed in a short time even if they are thrown into the soil without being incinerated for disposal after use.

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Claims (5)

[Claims] 1. A biodegradable thermoplastic synthetic resin comprising a molded product and / or a filament made of a polymer or copolymer comprising one or more selected from lactic acid, glycolic acid and caprolactone. Biodegradable oral cleaning tool. 2. The biodegradable oral cavity cleaning tool according to claim 1, wherein the biodegradable thermoplastic synthetic resin contains 1% by weight or more and 25% by weight or less of a plasticizer. 3. The biodegradable oral cleaning tool according to claim 2, wherein the plasticizer is citric acid ester and / or lactate ester. 4. The biodegradable oral cleaning tool according to claim 1, wherein the biodegradable filament has a tensile strength of 3 g or more per denier. 5. The biodegradable oral cleaning tool according to claim 1, wherein the oral cleaning tool is a dental floss or a dental floss pick.