JPH0810272A - Biodegradable intraoral cleaning means - Google Patents

Abstract

PURPOSE:To obviate generation of pollution problems by providing an intraoral cleaning means which is formed by using a biodegradable thermoplastic resin and is rapidly decomposed even when this means is thrown into soil in throwing after the use thereof. CONSTITUTION:This biodegradable intraoral cleaning means is formed of the thermoplastic synthetic resin which consists of moldings or filaments consisting of a copolymer polyester resin of a 3-hydroxybuthylate and 3-hydroxyparylate and has bio-degradation property. The molar fraction of the 3-hydroxyparylate constituting the moldings is preferably >=2 to <=12% and the stretching magnification of the filaments is preferably >=4 times. The bio-degradable intraoral cleaning means is preferably dental froth and dental froth pick. Then, the bio-degradable intraoral cleaning means described above are producible at a low cost as existing equipment and metal molds are usable.

Description

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 for a resin-made one end that is sharpened to form a pick, and the other end is arcuately formed to adhere 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. Moreover, 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 it not cause the environmental problems mentioned above, but it also has the effect that these components decompose in the soil and also act as organic fertilizers, so it can even be actively used as fertilizers.

Copolymerized polyester resin of 3-hydroxybutyrate and 3-hydroxyvalerate is desirable as the thermoplastic synthetic resin having biodegradability. This resin is
It is sold by Zeneca under the name Biopol. 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.

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 draw ratio of 4 times or more. If the draw ratio is less than 4 times, the strength may be insufficient and the durability may be poor. Further, the molar fraction of 3-hydroxyvalerate in the copolymer constituting the injection-molded article is preferably 2% or more and 12% or less. If the mole fraction of 3-hydroxyvalerate is less than 2%, it is brittle, and if it exceeds 12%, the elastic modulus is too low and it becomes difficult to use. 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.

[0011]

【Example】

Example 1 A copolymer polyester resin in which the molar ratios of 3-hydroxybutyrate and 3-hydroxyvalerate were 92% and 8%, respectively, using an injection molding machine with a mold clamping pressure of 140 tons, and an 8-storied mold. Then, injection molding was performed at a resin temperature of 160 ° C. to obtain a toothbrush handle. A monofilament obtained by spinning a copolymer polyester resin in which the molar ratios of 3-hydroxybutyrate and 3-hydroxyvalerate are 90% and 10%, respectively, at a draw ratio of 7 times to this handle is flocked by a Tsujimura type hair transplanter. And got 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 handle made of polypropylene by injection molding.
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 2-7, 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.

[0013]

[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.

[0015]

[Effect] The biodegradable oral cleaning tool according to the present invention can be used at present even by using a biodegradable thermoplastic resin composed of a copolymer polyester resin of 3-hydroxybutyrate and 3-hydroxyvalerate. The equipment and mold can be used as they are, or with only minor changes, and production can be performed 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.

Claims (4)

[Claims] 1. A biodegradable oral cleaning tool formed from a copolymerized polyester resin of 3-hydroxybutyrate and 3-hydroxyvalerate. 2. The biodegradable oral cleaning tool according to claim 1, wherein the molar ratio of the 3-hydroxyvalerate copolymer constituting the injection-molded article is 2% or more and 12% or less. 3. The biodegradable oral cleaning tool according to claim 1, wherein the monofilament or multifilament made of a copolyester resin of 3-hydroxybutyrate and 3-hydroxyvalerate has a draw ratio of 4 times or more. 4. The biodegradable oral cleaning tool according to claim 1, 2, or 3, wherein the oral cleaning tool is a dental floss or a dental floss pick.