JP2007023215A - Biodegradable wire-like article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biodegradable wire-like article which has biodegradability, a dead fold property and a fabrication property. <P>SOLUTION: This biodegradable wire-like article comprising 75 to 95 mass% of a lactate-based resin and 5 to 25 mass% of an aliphatic polyester-based resin except the lactate-based resin is characterized in that the aliphatic polyester-based resin has a crystallization peak in a temperature range of 50 to 90°C, when the resin is cooled from the crystal-melting temperature of the aliphatic polyester-based resin to a glass transition temperature at a rate of 10°C/min; the relation of the glass transition temperature Tg(A) of the lactate-based resin to the crystal-melting temperature Tm(B) of the aliphatic polyester-based resin satisfies an inequality: Tg(A)<Tm(B); and the crystal-melting calorie ΔHm(B) of the aliphatic polyester-based resin is 50 to 80 J/g. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a biodegradable wire-like material having biodegradability, dead hold property, and secondary processability.

  For example, a wire-like material used for a ring notebook binding tool or the like particularly needs dead hold property and secondary workability. Metal wires have been mainly used for these wire-like materials, but metal wires need to be separated at the time of disposal. In recent years, in order to solve the problem of separation at the time of disposal, metal wire substitutes have been developed. For example, wire-like materials mainly composed of polyethylene terephthalate are used in some ring notebook binding tools, etc. Has been.

  However, even a ring notebook using a polyethylene terephthalate wire-like material as a binding tool needs to be separated from paper when discarded. In addition, the binding device of the notebook is required to be stopped in order to prevent the paper from coming off at both ends of the notebook. However, since polyethylene terephthalate is inferior in the dead hold property, the fastening process cannot be performed in the same manner as the metal. Patent Document 1 discloses a wire-like material using urethane, silicon or the like as a soft material having flexibility, but these materials are also inferior in dead hold property and / or secondary workability. Therefore, it was difficult to apply to a wide range of uses.

JP 2000-141973

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a biodegradable wire-like material having biodegradability, dead hold property, and secondary workability. There is to do.

  The biodegradable wire-like product of the present invention comprises 75 to 95% by mass of a lactic acid resin and 5 to 25% by mass of an aliphatic polyester resin other than the lactic acid resin. When the temperature is lowered at a rate of 10 ° C./min from the crystal melting temperature of the group polyester resin to the glass transition temperature, a crystallization peak appears between 50 ° C. and 90 ° C., and the glass transition temperature Tg ( A) and the crystalline melting temperature Tm (B) of the aliphatic polyester resin satisfy the inequality Tg (A) <Tm (B), and the heat of crystal melting ΔHm (B) of the aliphatic polyester resin. Is 50 J / g or more and 80 J / g or less.

  In the present invention, an inorganic filler can be further blended in an amount of 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the mixture of the lactic acid resin and the aliphatic polyester resin.

  Moreover, 0.1 mass part or more and 5 mass parts or less of the ester compound whose molecular weight is 200-2000 can be further mix | blended with respect to 100 mass parts of the mixture of the said lactic acid-type resin and the said aliphatic polyester-type resin. .

  Moreover, 0.1 mass part or more and 5 mass parts or less of a carbodiimide compound can further be mix | blended with respect to 100 mass parts of mixtures of the said lactic acid-type resin and the said aliphatic polyester-type resin.

ADVANTAGE OF THE INVENTION According to this invention, it has biodegradability and can provide the biodegradable wire-like thing excellent in dead hold property and secondary workability.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described below.
The biodegradable wire-like product of the present invention mainly comprises a mixture in which 75 to 95% by mass of a lactic acid resin and 5 to 25% by mass of an aliphatic polyester resin other than the lactic acid resin are mixed to 100% by mass. It consists of a resin composition as a component. By blending the lactic acid-based resin and the aliphatic polyester-based resin within such a range, excellent dead hold property and secondary processability can be expressed.

(Lactic acid resin)
The lactic acid-based resin used in the present invention includes poly (L-lactic acid) having a structural unit of L-lactic acid, poly (D-lactic acid) having a structural unit of D-lactic acid, and structural units of L-lactic acid and D-lactic acid. And poly (DL-lactic acid), or a mixture thereof.

  In the lactic acid resin used in the present invention, the DL composition ratio of the lactic acid resin is L-form: D-form = 100: 0 to 90:10, or L-form: D-form = 0: 100 to 10:90. It is preferable that L-form: D-form = 99.5: 0.5 to 94: 6, or L-form: D-form = 0.5: 99.5 to 6:94. Outside this range, the heat resistance of the product formed is difficult to obtain, and the application may be limited.

  The polylactic acid resin used in the present invention may be an aliphatic diol and / or an aliphatic diol and / or a copolymer with other hydroxycarboxylic acid units such as α-hydroxycarboxylic acid other than lactic acid. It may be a copolymer with a dicarboxylic acid.

  As other hydroxy-carboxylic acid units, optical isomers of lactic acid (D-lactic acid for L-lactic acid, L-lactic acid for D-lactic acid), glycolic acid, 3-hydroxybutyric acid, 4-hydroxy Bifunctional aliphatic hydroxycarboxylic acids such as butyric acid, 2-hydroxyn-butyric acid, 2-hydroxy-3,3-dimethylbutyric acid, 2-hydroxy-3-methylbutyric acid, 2-hydroxycaproic acid, caprolactone, butyrolactone, valerolactone And lactones.

  Examples of the aliphatic diol copolymerized with the lactic acid resin include ethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol and the like. Examples of the aliphatic dicarboxylic acid include succinic acid, adipic acid, suberic acid, sebacic acid, and dodecanedioic acid.

In the present invention, a non-aliphatic dicarboxylic acid such as terephthalic acid and / or a non-aliphatic such as an ethylene oxide adduct of bisphenol A is used as a small amount of a copolymer component in order to improve heat resistance. Diols and the like may be used.
For the purpose of increasing the molecular weight, a small amount of a chain extender such as a diisocyanate compound, an epoxy compound, or an acid anhydride can be used.

  The weight average molecular weight of the lactic acid resin is preferably in the range of 50,000 to 400,000, more preferably in the range of 100,000 to 250,000. If the weight average molecular weight of the lactic acid-based resin is 50,000 or more, practical properties such as mechanical properties and heat resistance are expressed, and if it is 400,000 or less, the melt viscosity is not too high, and good moldability is obtained. Have.

  As a polymerization method of the lactic acid-based resin, it can be produced by a known method such as a condensation polymerization method or a ring-opening polymerization method. For example, in the condensation polymerization method, L-lactic acid, D-lactic acid, or a mixture thereof can be directly subjected to dehydration condensation polymerization to obtain a lactic acid resin having an arbitrary composition.

  In addition, in the ring-opening polymerization method, lactide, which is a cyclic dimer of lactic acid, is subjected to ring-opening polymerization in the presence of a predetermined catalyst while using a polymerization regulator or the like as necessary, and a lactic acid system having an arbitrary composition. A resin can be obtained. Lactide includes L-lactide, which is a dimer of L-lactic acid, D-lactide, which is a dimer of D-lactic acid, and DL-lactide composed of L-lactic acid and D-lactic acid, which are necessary. By mixing and polymerizing according to the above, a lactic acid resin having an arbitrary composition and crystallinity can be obtained.

  Typical commercial products of lactic acid-based resins include Laissia series manufactured by Mitsui Chemicals, NatureWorks series manufactured by Cargill Dow, and the like.

(Aliphatic polyester other than lactic acid resin)
As described above, the biodegradable wire-like product of the present invention comprises a lactic acid resin and an aliphatic polyester resin other than the lactic acid resin. Aliphatic polyester resins other than this lactic acid resin are between 50 ° C. and 90 ° C. when the temperature is lowered at a rate of 10 ° C./min from the crystal melting temperature Tm (B) of the aliphatic polyester resin to the glass transition temperature. Has a crystallization peak. In addition, the temperature which shows this crystallization peak is displayed as crystallization peak temperature Tc (B). In addition, aliphatic polyester resins other than lactic acid resins have a crystal melting temperature Tm (B) satisfying the relationship of Tg (A) <Tm (B) and a crystal melting heat ΔHm (B) of 50 J / g or more. It is necessary to be 80 J / g or less. That is, the aliphatic polyester resin needs to have a large heat of crystal fusion ΔHm (B) and a crystal melting temperature Tm (B) higher than the glass transition temperature Tg (A) of the lactic acid resin. . By blending an aliphatic polyester resin with a high crystallinity and a high melting point into the lactic acid resin, the drawdown during the secondary processing of the wire-like material, for example, the processing of a ring notebook binding tool, is suppressed, Secondary processing can be performed while maintaining a stable shape.

  The aliphatic polyester resin other than the lactic acid resin preferably has a crystallization peak temperature Tc (B) higher than the glass transition temperature Tg (A) of the lactic acid resin. That is, when the inequality of Tc (B)> Tg (A) is satisfied, crystallization of an aliphatic polyester other than the lactic acid resin starts in the cooling process after melt extrusion when obtaining a wire-like product, The shape of the extruded mixture is stable, and a wire-like product having an excellent appearance can be obtained.

  Aliphatic polyester resins other than the above lactic acid resins include aliphatic polyesters obtained by condensation polymerization of aliphatic diols and aliphatic dicarboxylic acids, those obtained by copolymerizing lactic acid resins with aliphatic polyesters, And aliphatic polyester carbonate obtained by copolymerizing carbonate with aliphatic polyester, and aliphatic polyester obtained by ring-opening polymerization of cyclic lactones.

  Specific examples of the aliphatic polyester resin other than the lactic acid resin include polybutylene succinate obtained by polymerizing succinic acid and 1,4-butanediol. "GSPla" AZ series manufactured by Co., Ltd. and "Bionore" # 1000 series manufactured by Showa Polymer Co., Ltd. are available, and are obtained by polymerizing succinic acid, 1,4-butanediol and carbonate. Examples thereof include polybutylene succinate carbonate. For example, “Eupec” series manufactured by Mitsubishi Gas Chemical Co., Ltd. is commercially available.

  The aliphatic polyester-based resin preferably has a weight average molecular weight in the range of 50,000 to 400,000, more preferably 100,000 to 250,000. When the weight average molecular weight of the aliphatic polyester resin is less than 50,000, practical physical properties are hardly expressed, and when it exceeds 400,000, the melt viscosity is too high and the molding processability tends to be inferior.

  In the present invention, the glass transition temperature Tg (A) of the lactic acid resin, the crystal melting temperature Tm (B) of the aliphatic polyester resin, the crystallization peak temperature Tc (B), and the heat of crystal melting ΔHm (B). Was determined by the following measurement method. That is, first, as a sample, pellets of a lactic acid-based resin and an aliphatic polyester-based resin other than the lactic acid-based resin were cut into scales each having a diameter of 5 mm and a weight of about 10 mg. This was heated at a rate of 10 ° C./min from 30 ° C. to 200 ° C. based on Japanese Industrial Standard JIS-K7121, using a differential scanning calorimeter DSC-7 manufactured by PerkinElmer, and then 200 ° C. For 2 minutes, and after melting the crystal, the temperature was lowered at a rate of 10 ° C./min to prepare a thermogram. Tg (A), Tm (B), Tc (B), and ΔHm (B) were read from the obtained thermogram.

(Inorganic filler)
The biodegradable wire-like product of the present invention can further contain an inorganic filler. By blending inorganic fillers with lactic acid-based resins and aliphatic polyester-based resins other than lactic acid-based resins, draw-down during secondary processing of wire-like materials is prevented, and workability such as stabilization of ring diameter Can be further improved.

  Examples of the inorganic filler used in the present invention include talc, kaolin, calcium carbonate, bentonite, mica, sericite, glass flake, graphite, magnesium hydroxide, aluminum hydroxide, antimony trioxide, barium sulfate, zinc borate, hydrous boron Examples thereof include calcium acid, alumina, magnesia, wollastonite, zonotlite, sepiolite, whisker, glass fiber, glass flake, metal powder, beads, silica balloon, and shirasu balloon. Moreover, in this invention, the adhesiveness with resin can be improved by processing the surface of these inorganic fillers with a titanic acid, a fatty acid, a silane coupling agent, etc., and the effect of an inorganic filler can also be improved further.

  As a compounding quantity of the said inorganic filler, it is preferable to mix | blend 1-50 mass parts of inorganic fillers with respect to 100 mass parts of mixtures of lactic acid-type resin and aliphatic polyester-type resins other than lactic acid-type resin, 5-40 More preferably, it is blended in an amount of 10 to 30 parts by weight. By mix | blending an inorganic filler in 1 mass part or more and 50 mass parts or less, workability can be improved, without reducing the mechanical strength of a wire-like thing, and fluidity | liquidity.

(Ester compound)
The biodegradable wire-like product of the present invention can further contain an ester compound. By blending the ester compound, not only the flowability of the resin at the time of molding the wire-like product can be improved, but also the impact resistance of the wire-like product can be improved.

  The ester compound preferably has a molecular weight in the range of 200 to 2,000, and more preferably in the range of 250 to 1,000. If the molecular weight of the ester compound is less than 200, the impact resistance improving effect may not be obtained, and the ester compound may bleed out to the surface of the molded product. When the molecular weight of the ester compound exceeds 2,000, the impact resistance improving effect may not be obtained, and the heat resistance of the wire-like product may be lowered.

  Specific examples of the ester compound used in the present invention include diisodecyl adipate, di (2-ethylhexyl) azelate, di (2-ethylhexyl) sebacate, di (2-ethylhexyl) dodecanedionate, acetyltributyl citrate, dibutyl sebacate Di (2-ethylhexyl) adipate, diisononyl adipate, dimethyl adipate, dibutyl adipate, tributyl citrate, acetyl tributyl citrate, triethyl citrate, diisobutyl adipate, di (2-ethylhexyl) dodecanedionate, dibutyl phthalate, diisononyl phthalate, 2-ethylhexyl benzyl phthalate, dimethyl phthalate, diheptyl phthalate, diisodecyl phthalate, di (2-ethylhexyl) phthalate, Squirrel (2-ethylhexyl) trimellitate, tributyl trimellitate, tri (2-ethylhexyl) trimellitate, glycerol triacetate, polyethylene glycol, and the like.

  Moreover, as a compounding quantity of the said ester compound, it is preferable to mix | blend 0.1-5 mass parts with respect to 100 mass parts of mixtures of lactic acid-type resin and aliphatic polyester-type resins other than lactic acid-type resin, and is 0.00. It is more preferable to mix 5 to 3 parts by mass. By blending the ester compound in the range of 0.1 parts by mass or more and 5 parts by mass or less, fluidity and wire at the time of forming a wire-like product without causing a significant decrease in heat resistance due to excessive addition of the ester compound. The impact resistance of the object can be improved.

(Carbodiimide compound)
The biodegradable wire-like product of the present invention can further contain a carbodiimide compound in order to impart hydrolysis resistance to the biodegradable wire-like product. Examples of the carbodiimide compound used include carbodiimide compounds having a basic structure represented by the following general formula.

- (N = C = N- R-) n -

In the above formula, n represents an integer of 1 or more, and R represents an organic bond unit. For example, R can be either aliphatic, alicyclic, or aromatic. Moreover, n is normally determined suitably between 1-50.

  Specific examples of the carbodiimide compound include bis (dipropylphenyl) carbodiimide, poly (4,4′-diphenylmethanecarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), and poly (tolylcarbodiimide). ), Poly (diisopropylphenylenecarbodiimide), poly (methyl-diisopropylphenylenecarbodiimide), poly (triisopropylphenylenecarbodiimide), and the like, and monomers thereof. These carbodiimide compounds may be used alone or in combination of two or more.

  As a compounding quantity of the said carbodiimide compound, it is preferable to mix | blend 0.1-5 mass parts with respect to 100 mass parts of mixtures of lactic acid-type resin and aliphatic polyester-type resins other than lactic acid-type resin, and 1-3 masses. It is more preferable to blend partly. When the amount of the carbodiimide compound is less than 0.1 parts by mass, the effect of imparting durability is low, and when the amount exceeds 5 parts by mass, the wire-like material is softened and heat resistance may be impaired. is there.

  The biodegradable wire-like product of the present invention includes a heat stabilizer, an antioxidant, a UV absorber, a plasticizer, a nucleating agent, a light stabilizer, a pigment, a dye and the like within a range not impairing the effects of the present invention. Additives can be blended.

  As a method for molding the biodegradable wire-like product of the present invention, for example, the following method is used.

  Mixing of lactic acid-based resins, aliphatic polyester-based resins other than lactic acid-based resins, and other additives can be performed by charging the respective raw materials into the same extruder. After mixing raw materials directly using an extruder, a resin is extruded with a strand die to form a wire-like product, or a dry blended raw material is extruded into a strand shape using a twin screw extruder and a lactic acid resin After preparing a mixed pellet of aliphatic polyester other than lactic acid resin and other additives, the resin is extruded from a strand die using a twin screw extruder or a single screw extruder to produce a wire-like product There is a way.

  The biodegradable wire-like material thus obtained can be subjected to secondary processing at room temperature and / or under heating. For example, the end of a biodegradable wire-like product can be bent to form a wire-like product suitable as a binding tool for a ring notebook. The processing temperature in the secondary processing is preferably in the range of not less than the glass transition temperature Tg (A) of the lactic acid resin and not more than {Tg (A) + 50 ° C.}, and more than {Tg (A) + 5 ° C.} or more {Tg ( A) + 40 ° C.} or less is more preferable, and {Tg (A) + 10 ° C.} or more and {Tg (A) + 30 ° C.} or less is particularly preferable.

  Since the wire-like product of the present invention has excellent dead hold property and secondary workability, a clip, a hanger, a toothbrush, a binding material, a ring notebook binding tool, an artificial rattan, a mask core material, an umbrella core material, etc. It can be widely used in the same manner as conventional miscellaneous goods and other conventionally used metals such as toys and nets.

  Examples are shown below, but the present invention is not limited by these. In addition, the result shown in an Example evaluated by the following method.

(1) Dead hold property The following evaluation was performed as dead hold property evaluation. That is, a 2 mmφ × 100 mm wire was bent at approximately the center so that the angle was 180 degrees, and the returned angle was measured. A return angle of 50 degrees or less was set as a practical standard for dead hold property.

(2) Storage elastic modulus at 80 ° C. The following evaluation was performed as an evaluation of secondary workability. That is, the measurement was performed at a vibration frequency of 10 Hz and a temperature of 80 ° C. using a viscoelastic spectrometer VES-F3 manufactured by Iwamoto Seisakusho. The storage elastic modulus at 80 ° C. was set to 50 MPa or more as a practical standard for secondary workability.

Example 1
As a lactic acid-based resin, Crystal Works 4032D manufactured by Cargill Dow (D content 1.4%, weight average molecular weight 200,000, Tg (A) = 65 ° C., Tm (A) = 170 ° C.), crystal GSPla AZ91T (polybutylene succinate, manufactured by Mitsubishi Chemical Corp.) as an aliphatic polyester in which a crystallization peak appears between 50 ° C. and 90 ° C. when the temperature is lowered from the melting temperature to the glass transition temperature at a rate of 10 ° C./min. Tm (B) = 110 ° C., Tc (B) = 72 ° C., ΔHm (B) = 59 J / g) were used. A mixture obtained by dry blending Nature Works 4032D and GSPla AZ91T at a mass ratio of 90:10 was kneaded at 200 ° C. by a 40 mmφ co-directional twin-screw extruder, extruded from a strand die, and then placed in a constant temperature bath at 20 ° C. And cooled to produce a 2 mmφ × 100 mm wire. Evaluation of dead hold property was performed about the obtained wire-like thing.

  Subsequently, the obtained wire-like product was pressed using a vacuum press (made by Kitagawa Seiki Co., Ltd., molding press VH1-1747) at 200 ° C. and 10.5 MPa until the thickness became 0.2 mm. It cut out to width 2mm and length 50mm, and measured the storage elastic modulus in 80 degreeC.

  Table 1 shows the evaluation result of the dead hold property and the measurement result of the storage elastic modulus at 80 ° C.

(Example 2)
After Nature Works 4032D and GSPla AZ91T were dry blended at a mass ratio of 80:20, wire-like materials were produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 3)
Microace L1 (talc, average particle size 4.9 μm) manufactured by Nippon Talc Co., Ltd. was used as the inorganic filler, and Nature Works 4032D, GSPla AZ91T, and Microace L1 were used at a mass ratio of 90:10:15. After dry blending, wire-like materials were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 4
After Nature Blends 4032D, GSPla AZ91T, and Microace L1 were dry blended at a mass ratio of 80:20:15, a wire-like product was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 5)
IUPEC PEC-350 (polyester) manufactured by Mitsubishi Gas Chemical Co., Ltd. as an aliphatic polyester in which a crystallization peak appears between 50 ° C. and 90 ° C. when the temperature is lowered from the crystal melting temperature to the glass transition temperature at a rate of 10 ° C./min. Butylene succinate carbonate, Tm (B) = 104 ° C., Tc (B) = 53 ° C., ΔHm (B) = 55 J / g), using Nature Works 4032D and IUPEC PEC-350 in a mass ratio of 80:20 After dry blending at a ratio of 1, a wire-like material was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Comparative Example 1)
A wire-like material was prepared and evaluated in the same manner as in Example 1 except that only the Nature Works 4032D was used without using an aliphatic polyester resin. The results are shown in Table 1.

(Comparative Example 2)
A wire-like product was prepared and evaluated in the same manner as in Example 1 except that only GSPla AZ91T was used without using a lactic acid resin. The results are shown in Table 1.

(Comparative Example 3)
After Nature Works 4032D and GSPla AZ91T were dry blended at a mass ratio of 60:40, a wire-like product was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Comparative Example 4)
Bionore 3003 (polybutylene succinate adipate, Showa Polymer Co., Ltd., weight average molecular weight 200,000, Tm (B) = 90 ° C., Tc (B) = 57 ° C., ΔHm (B) = 39 J / g) Then, after Nature Blends 4032D and Bionore 3003 were dry blended at a mass ratio of 80:20, a wire-like product was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Comparative Example 5)
A wire-like product was prepared and evaluated in the same manner as in Example 1 except that only Unipet RT523C (polyethylene terephthalate, IV = 0.7) manufactured by Nippon Unipet Co., Ltd. was used as a raw material. The results are shown in Table 1.

(Comparative Example 6)
A wire-like material was prepared and evaluated in the same manner as in Example 1 except that only F274NP (polypropylene) manufactured by Idemitsu Petrochemical Co., Ltd. was used as a raw material. The results are shown in Table 1.

As is clear from Table 1, the biodegradable wire-like materials of Examples 1 to 5 were found to have a return angle of 50 degrees or less and excellent dead hold property. In addition, the storage elastic modulus at 80 ° C. is 50 MPa or more, the elastic modulus lowering of the lactic acid resin under heating during the secondary processing can be suppressed, and the secondary processing property is excellent. I understood. In addition, the wire-like materials of Examples 1 to 5 are biodegradable because they are mainly composed of a lactic acid-based resin and an aliphatic polyester-based resin, and are decomposed into water and carbon dioxide by natural microorganisms and degrading enzymes after use. Is done. For this reason, it can be buried in the ground as a treatment after disposal, and when it is burned, the amount of combustion heat is low, and no harmful substances such as dioxins are released.
There was no separation problem at the time of disposal.

  On the other hand, Comparative Example 1 consisting only of lactic acid-based resin, Comparative Example 2 consisting only of aliphatic polyester-based resin, Comparative Example 3 where the blending ratio of lactic acid-based resin and aliphatic polyester-based resin is outside the present invention, ΔHm is 50 J / The wire-like product of Comparative Example 4 in which an aliphatic polyester-based resin of less than g is blended, Comparative Example 5 made of polyethylene terephthalate, and Comparative Example 6 made of polypropylene has either one of dead hold property and secondary processability. It was bad.

  That is, according to the present invention, it is possible to eliminate the separation problem at the time of disposal of the metal wire, and to improve the dead hold property and the secondary workability that were the problems of the metal wire substitute plastic material. I was able to.

Since the wire-like product of the present invention has excellent dead hold properties and secondary workability, clips, hangers, toothbrushes, binding materials, binding devices for ring notebooks, artificial rattan, mask core materials, umbrella core materials, etc. It can be used for a wide range of applications similar to that of conventionally used metal such as toys, nets, etc.

Claims (4)

  It is composed of 75 to 95% by mass of lactic acid resin and 5 to 25% by mass of aliphatic polyester resin other than lactic acid resin, and the aliphatic polyester resin undergoes a glass transition from the crystal melting temperature of the aliphatic polyester resin. When the temperature is lowered to a temperature of 10 ° C./min, a crystallization peak appears between 50 ° C. and 90 ° C., and the glass transition temperature Tg (A) of the lactic acid resin and the aliphatic polyester resin The relationship with the crystal melting temperature Tm (B) satisfies the inequality Tg (A) <Tm (B), and the heat of crystal melting ΔHm (B) of the aliphatic polyester resin is 50 J / g or more and 80 J / g or less. A biodegradable wire-like product characterized by that.   The biodegradable wire-like product according to claim 1, wherein an inorganic filler is further blended in an amount of 1 to 50 parts by mass with respect to 100 parts by mass of the mixture of the lactic acid resin and the aliphatic polyester resin.   2. An ester compound having a molecular weight of 200 or more and 2000 or less is further blended by 0.1 to 5 parts by mass with respect to 100 parts by mass of a mixture of the lactic acid resin and the aliphatic polyester resin. Or the biodegradable wire-like thing of 2 description.   The carbodiimide compound is further blended in an amount of 0.1 parts by mass to 5 parts by mass with respect to 100 parts by mass of the mixture of the lactic acid resin and the aliphatic polyester resin. Biodegradable wire.