JPH11181261A - Biodegradable resin molded product - Google Patents

Abstract

(57) [Abstract] [Problem] Biodegradability that is decomposed by the action of microorganisms existing in nature even when discarded, and does not cause destruction of the natural environment or waste pollution, and maintains practically sufficient strength Provide a molded article made of resin. The molded article comprises a biodegradable resin mainly composed of a polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester, and starch, and the starch portion particles are dispersed in the aliphatic polyester. It has the following structure. Preferably, the ratio of starch to the total weight of the resin material is 10 to 60% by weight. Such molded products are
It can be used as a product in various fields by molding into a desired shape, but in order to maintain sufficiently high strength,
In particular, it can be advantageously applied to a slide fastener and a hook-and-loop fastener.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biodegradable resin molded article comprising a polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester having a biodegradable function and starch. In particular, it relates to a fastener molded product processed by injection molding and extrusion molding.

[0002]

2. Description of the Related Art Polybutylene succinate and polyethylene adipate, which are biodegradable resins, are one type of aliphatic polyester mainly synthesized chemically from glycol and aliphatic dicarboxylic acid. Its main chemical structural formula is represented by the following general formulas (1) and (2).

Embedded image Among these, as for polybutylene succinate, the biodegradable resin "Bionore" containing it as a main component is already on the market, and "TECHNICAL DATA SHEET, Decomposable Plastics (1996) "provides an overview, properties and structure. This aliphatic polyester is stable in air, such as wood and paper, but biodegrades in compost, wet soil, activated sludge, freshwater and seawater, and ultimately water and carbon dioxide Is decomposed into

Conventionally used synthetic resin products include:
Due to its excellent properties of being lightweight, inexpensive and easy to process, it has penetrated every part of our daily life and has become an indispensable material in modern economic society. Fasteners are no exception, and resin fasteners using synthetic resins are utilized in various products by utilizing their features. However, when these synthetic resin products are discarded after use, they accumulate in the natural environment without being decomposed as they are, causing pollution problems such as destruction and pollution of the natural environment. On the contrary,
Although there are few practical examples, products using a biodegradable resin with a small load on the natural environment have appeared as an alternative to the existing synthetic resin.

[0004]

However, when the above-mentioned biodegradable resin is used as an actual product such as a fastener, there are many problems to be solved such as strength and moldability. However, at present, no biodegradable resin satisfying all these requirements has been put on the market. Accordingly, an object of the present invention is to develop a treatment method capable of imparting sufficient strength to a biodegradable resin to be used as a fastener or the like, thereby causing pollution problems such as destruction and pollution of the natural environment even if disposed after use. An object of the present invention is to provide a molded article made of a biodegradable resin which does not have any practical properties and retains sufficient mechanical properties.

[0005]

According to the present invention, starch is added to a biodegradable resin containing polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester as a main component. The present invention provides a biodegradable resin molded product characterized by being produced from a resin material prepared as described above. Preferably, the ratio of starch to the total weight of the resin material is 10 to 60% by weight. Such a biodegradable resin molded article can be used as a product in various fields by molding it into a desired shape, but can be advantageously applied to a slide fastener and a hook-and-loop fastener, in particular, because it maintains a sufficiently high strength.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a use as a fastener or the like by adding starch such as cornstarch or potato starch to a polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester which is a biodegradable resin. It is intended to improve the strength so as to be able to withstand the problem sufficiently and to bring out better performance. In the category of conventional synthetic resins, this technique is a technique of adding a filler to a polymer.
For example, it is described in detail in Masayuki Furuya, “Plastic Materials Course 18 Vinyl Chloride Resin”, published by Nikkan Kogyo Shimbun (1972). The present inventors have conducted intensive studies on the strength of the biodegradable resin, which is a problem in using the biodegradable resin for fasteners and the like. As a result, the biodegradable resin material polybutylene succinate and / or Or, by adding starch to polyethylene adipate-based aliphatic polyester, the flexural strength and flexural modulus of the biodegradable resin material are increased, and the strength is dependent on the added amount of starch. Was. Furthermore, the processing method and the solution for solving the above-mentioned problem were confirmed by experiments, and the strength of an actual injection-molded fastener was enhanced by appropriately applying the method to an actual product, thereby completing the present invention.

In general, in a polymer material, tensile strength, hardness, bending rigidity and tear resistance are changed by adding a fine particle filler. For example, such a phenomenon is observed in the addition of calcium carbonate to a vinyl chloride resin (also described in the above-mentioned publication). When starch is added to polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester, the tensile strength is considerably reduced,
When the amount of added starch exceeds 20% by weight of the total amount, the amount gradually decreases, but the flexural strength and flexural modulus increase as shown in FIGS. 16 and 17 described later. As a result, it was confirmed that when a fastener product was molded from the biodegradable resin material, the strength of the fastener increased as the amount of added starch increased to a certain extent.

[0008] In the transverse pulling test of the fastener, the force applied to the fastener is a force in both directions of tension and compression, but the compressive strength is dominant in the transverse pulling strength of the fastener. In the case of a fastener using a resin having a low compressive strength, as a result of a lateral pulling test, the engaging portion of the engagement tooth comes off. Such a phenomenon is called chain breaking. On the other hand, for fasteners using resin with high compressive strength,
The fastener's teeth are removed from the tape. This kind of phenomenon is called elimination. This indicates that by measuring the bending strength, the transverse pulling strength and the breaking state of the fastener can be evaluated. In fact, as shown in FIG. 18 described later, the transverse pull strength of the fastener is higher in the resin material to which starch is added than in the case of the aliphatic polyester alone, and particularly 10 to 10 with respect to the total weight of the resin material.
High lateral draw strength is obtained at a starch addition amount of 60% by weight.

As the biodegradable resin, polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester used in the present invention, those produced by a known method can be used without any particular limitation. Further, the method for producing a molded article of the present invention is not limited to a specific method. To give an example of the most typical production method, first, the aliphatic polyester and the starch are kneaded at about 190 ° C. using a kneading apparatus at a weight ratio of a large amount of the aliphatic polyester. Next, the kneaded resin is molded by an injection molding machine, whereby the starch portion particles have a two-phase structure dispersed in an aliphatic polyester medium, and are made of a higher-strength biodegradable resin. Injection molded products can be obtained easily and with good reproducibility. The kneading temperature is not limited to the above-mentioned temperature, and may be kneaded at that temperature as long as it is equal to or higher than the melting temperature of the resin. Regarding a method of kneading both components, a method of not using a kneading apparatus, that is, a method of mixing both components in the form of pellets and powder before molding can also be adopted.

Although the biodegradable resin molded article of the present invention is applicable to various fields, it has a sufficiently high strength and can be advantageously used for slide fasteners and hook-and-loop fasteners. Hereinafter, the application of the present invention to various fasteners will be specifically described with reference to the accompanying drawings. FIG.
Shows a slide fastener 1 used for opening and closing an opening of clothes or bags, for example, and has a product form in which upper and lower ends of a pair of left and right fastener stringers 2 are cut off. The fastener stringer 2 is composed of a biodegradable resin fastener tape 3 and a row of biodegradable resin elements (coil-shaped elements) 4 fixed to their facing edges. The fastener tape 3 is formed by weaving and / or knitting a biodegradable resin fiber, a nonwoven fabric, or a biodegradable resin sheet. As the element 4, an injection type in which individual elements are injection-molded and fastened to the edge of the fastener tape at the same time, a coil-shaped element in which a biodegradable resin monofilament is wound in a coil shape, and a horizontal direction in a plane. A continuous element such as a so-called zigzag element in which a portion bent in a U-shape is continuously formed in a zigzag shape along the longitudinal direction alternately up and down, and separated in parallel in the longitudinal direction by extrusion molding.
Various types of extruded elements, such as a ladder-shaped extruded element formed by connecting both ends of each element to a book connecting cord (core cord) and bending in a U-shape around a longitudinal center line. There is something. Further, for example, in the case of a coil-shaped element, a core string or a sewing thread is further added as a component. Reference numeral 5 is a slider for sliding and meshing / separating on opposing elements.

The slide fastener 1a shown in FIG. 2 has a form in which the upper end of each fastener stringer 2 is cut, and a lower stop 6 is formed by welding a predetermined lower position of the row of the meshed elements 4. This is different from the slide fastener shown in FIG. On the other hand, the slide fastener 1b shown in FIG. 3 is an element 4 fixed to the fastener tape 3b of each fastener stringer 2b.
The slide fastener shown in FIG. 1 is different from the slide fastener shown in FIG. 1 in that an upper stopper 7 is fixed to the upper end of the row b and a lower stopper 8 is fixed to the lower end.

FIG. 4 shows an open type slide fastener 1c. An adhesive layer (not shown) is provided at the lower end of the fastener tape 3c of each fastener stringer 2c.
A reinforcing sheet-like member (taffeta) 9 is welded through the opening. A box 11 constituting a separable bottom end stop 10 is attached to one inner edge of the facing reinforcing sheet-like member 9, and a butterfly pin is attached to the inner edge of the other reinforcing sheet-like member 9. 17 are attached. The box body 11 is formed integrally with the guide projections 13 and the box rods 12 on the sides thereof, and a concave groove 14 is formed between the box rod 12 and the guide projections 13 so that the lower end of the slider 5 can slide. Have been. Similarly, the integrally formed butterfly pin 17 and the guide ridge 1 on its side are provided.
8, a guide groove 19 is also formed. Box 11
Is formed with a butterfly pin insertion hole 15 penetrating in the vertical direction in the left part of the hole.
6 are formed. Therefore, when inserting the butterfly pin 17 into the butterfly pin insertion hole 15 of the box 11, the inside of the lower end of the guide ridge 18 slides along the edge of the side groove 16 of the box 11, and guides the insertion of the butterfly pin 17. Therefore, the insertion operation can be performed smoothly. In FIG. 4, reference numeral 20 denotes a coiled element 4c.
The reference numeral 21 denotes a sewing thread in which the core string 20 and the coil-shaped element 4c are sewn to the longitudinal edge of the fastener tape 3c.

As the separable bottom end stop, a so-called reverse open type is known, which can be disassembled or closed from the lower end of the slide fastener by forming a box similar to the structure of the slider 5 into a box. It is not limited to the one shown in FIG. Furthermore, in the illustrated example, the reinforcing sheet-shaped member separate from the separable bottom end stop is described as being welded to the lower end portion of the fastener tape, but the sheet-shaped portion is formed of a biodegradable resin material into a box or a butterfly pin. Integrally molded with a reinforcing piece and a separable insert such as one that is integrally injection-molded and attached to the entire width of the fastener tape, or one that has a sheet-shaped part with a slit or the like with an arbitrary pattern to give flexibility. There was something
Not limited to a specific one.

According to the present invention, the above-mentioned fastener tape, element, slider, up / down stopper, sewing thread, core string,
All of the separable bottom end stop and the sheet-like member for reinforcement can be made from the above-described biodegradable resin of the present invention, or some members are made from other biodegradable resins or synthetic resins. You can also. When manufacturing a resin slide fastener, a suitable resin material depends on the product form of the slide fastener and the structure of each component. Depending on the required function and structure, for example, the slider itself may need to be made of another resin or metal. In such a case, the slider can be made of a required material. In addition, the present invention can be applied not only to the slide fastener of the type described above but also to other types such as a rail fastener.

A surface fastener made of a biodegradable resin is required to have sufficient engagement force and durability even after repeated use to some extent in terms of its function. The engaging element of the hook-and-loop fastener is small or thin, so that biodegradation by microorganisms proceeds relatively smoothly, but biodegradation hardly proceeds because the base has a certain thickness. If the base is made thinner, biodegradation by microorganisms will easily proceed, but on the other hand, durability and strength will decrease.
Therefore, in a preferred embodiment, at least the base of the hook-and-loop fastener has a cross-sectional shape that increases its specific surface area. For example, a groove and / or a hole is formed in at least the base, or the inside of the engaging element is formed from the back of the base. To form a hole extending to. In addition, the hole here means
It should be understood as a concept including both aspects of a through hole and a non-through hole (or concave portion). In the flat base,
Making the surface rough is also an effective means.
As described above, by increasing the specific surface area of the base of the hook-and-loop fastener, the decomposition of the base by the action of microorganisms can be rapidly progressed while ensuring sufficient durability and strength. In addition, by forming the groove and / or the hole in the base, flexibility can be given to the base. Therefore, the engagement between the engagement elements can be quickly performed by the deformation of the base, and an improvement in the engagement force can be expected. .

The production of the hook-and-loop fastener of the present invention can be carried out by various conventionally known methods except that the material used is a biodegradable resin, and the form is also limited to a specific one. is not. For example, as the male member, engaging elements of various shapes such as an engaging element having a hook shape, an engaging element having a semi-spherical head, and an engaging element having a conical head project from the base. Fasteners formed integrally from biodegradable resin and hook-and-loop fasteners formed by cutting loops protruding from a base fabric made of woven or knitted biodegradable resin fibers Can also be used, and also as a female member, a thing woven and knitted in a pile shape so as to form a loop from biodegradable resin fibers, a thing formed with a large number of loops on the surface by raising a woven or knitted fabric, or a nonwoven fabric As long as the engaging element of the male member can be engaged, all can be used. Furthermore, the head of the engaging element is shaped such that the hooks protrude in both directions or in multiple directions, so that these hooks engage with each other, thereby simultaneously functioning as a male member and a female member. The hook-and-loop fastener configured to perform the above-described process may be used.

Hereinafter, various embodiments of the biodegradable resin surface fastener of the present invention will be specifically described with reference to the drawings. 5 and 6 show a first embodiment of the biodegradable resin surface fastener of the present invention. FIG. 5 is a perspective view of the male fastener 30 and FIG. 6 is a view of the male fastener 30 and the female fastener 40. The state of engagement is shown. Male surface fastener 3
Reference numeral 0 denotes a base 31 and a plurality of hook-shaped engaging elements 32 projecting from the base, which are integrally formed from the biodegradable resin as described above. It is formed so as to straddle the reinforcing ribs 33 arranged at predetermined intervals in the longitudinal direction. Also, on the back surface of the base 31,
Grooves (longitudinal grooves) 34 extending in the longitudinal direction are formed so that decomposition by the action of microorganisms can proceed promptly and maintain appropriate flexibility and strength. A vertical rib 35 is formed between them. As shown in FIG. 6, the male fastener 30 includes a female fastener 40 in which a number of loop-shaped engaging elements 42 are protruded from the surface of a base 41 woven or knitted from fibers of a biodegradable resin. The hook-shaped engaging element 32 is
2 is engaged by being hooked.

7 and 8 show a second embodiment of the surface fastener made of a biodegradable resin according to the present invention. FIG. 7 is a perspective view of the male surface fastener 30a, and FIG. 8 is a male surface fastener 30a and a female surface fastener 40. 3 shows the engagement state. The male surface fastener 30a of the present embodiment is characterized in that an engaging element 32a formed of a pair of adjacent hook pieces 36 and 37 whose hook-shaped tips are opposite to each other is protruded on the base 31a as an engaging element. 33a is formed intermittently only at the base end of each engagement element 32a, and a lateral groove (transverse groove) 34a is formed on the back surface of the base 31a to secure bending in the lateral direction. In that it differs from the first embodiment. The configuration of the female surface fastener 40 is the same as that of the first embodiment. The male fastener made of a biodegradable resin as described above is suitable for a molding apparatus described in, for example, U.S. Pat. No. 3,321,583 and JP-A-6-38811 (for example, a projection for forming a groove on a die). , Addition of a groove forming roll, etc.).

FIGS. 9 and 10 show a third embodiment of the biodegradable resin surface fastener according to the present invention, which shows a piece-shaped surface fastener 30b of the same type of male and female. The hook-and-loop fastener 30b includes a base 31b and a large number of engagement elements 3
2b is integrally formed from a biodegradable resin in the same manner as in the above embodiment, except that the engaging element 32b has a head composed of a pair of hook pieces 36b and 37b protruding in an arc shape on both sides, Further, a difference is that a large number of longitudinal grooves 34b are formed on the upper surface of the base 31b at the joint portion of the engagement element 32b, and holes 38b are formed on both sides of the engagement element 32b of the groove 34b. . By forming such a groove 34b and a hole 38b in the base 31b of the hook-and-loop fastener 30b, the action of decomposing by microorganisms can be accelerated, and the hook-and-loop fastener can be given appropriate flexibility and strength. The hook-and-loop fastener 30b has a pair of hook pieces 36b, 3 protruding on both sides.
7b, the hook pieces of one hook-and-loop fastener can be engaged with the hook pieces of the other hook-and-loop fastener by overlapping the two engaging elements so that they face each other. In the case of the hook-and-loop fastener 30b of the present embodiment, it can be formed by injecting biodegradable resin into the cavities of the upper mold and the lower mold having cavity surfaces of a predetermined shape. Also, unlike the embodiment described above,
Since it is molded into a piece (one piece) having a predetermined area, a large number of surface fasteners 30b are arranged and used adjacent to each other when used in a large area.

FIGS. 11 and 12 show a fourth embodiment of the male surface fastener made of a biodegradable resin according to the present invention. A monofilament or a multifilament is made of a biodegradable resin and the surface is woven. The fastener is shown. In the female surface fastener 40a shown in FIG. 11, a pile (base cloth) 4 made of a biodegradable resin filament is similarly plain-woven from the biodegradable resin filament.
A female engaging element 4 woven into a pile in a
2a is formed to protrude from the base surface. On the other hand, the male surface fastener 30c shown in FIG. 12 has the same structure as the above-mentioned female surface fastener except that a part of the loop is cut to form the hook-shaped engaging element 32c.
The hook-and-loop fastener shown in FIG. 12 can be used as a hook-and-loop fastener of the same type. A back coat 45 of a water-soluble resin or a biodegradable resin is applied to the back surfaces of the female fastener 40a and the male fastener 30c to prevent fraying. In addition, this back coat 4
By using a water-soluble resin for 5, the back coat 45 functions as an adhesive layer when moistened with water. In addition, even if such hook-and-loop fasteners 30c and 40a are discarded, a portion (3) made of a biodegradable resin is used.
1c, 32c, 41a, and 42a) are decomposed by the action of microorganisms, and the portion of the back coat 45 made of a water-soluble resin is dissolved and lost by rainwater or the like. Does not occur.
In addition, since the back coat 45 of the water-soluble resin dissolves and disappears, the bases (base cloths) 31c and 41a become woven cloth of biodegradable resin filaments having a large number of voids, so that the decomposing action by microorganisms is promptly performed. proceed.

FIGS. 13 and 14 show a fifth embodiment of the biodegradable resin surface fastener according to the present invention, in which a hole and a groove are formed in the base of the surface fastener by elution of a water-soluble resin into a solvent. An example is shown. The shape of the engaging element 32d of the male surface fastener 30d is the same as that of the embodiment shown in FIG. In this case, a part of the engaging element 32d and a part of the base 31d of the male surface fastener 30d is made of a biodegradable resin, and a part to be a hole and a groove of the base is made of a water-soluble resin 46.
After immersion in a solvent such as water or an aqueous alcohol solution to elute the water-soluble resin 46, a male surface having a hole 38d and a groove 34d formed in the base 31d as shown in FIG. A fastener 30d is obtained. In addition, as shown in FIG. 13, the male surface fastener 30d in which the water-soluble resin 46 is laminated on the back surface of the base 31d can be used as it is. In this case, the water-soluble resin 4
6 functions as an adhesive layer by moistening it with water.
Further, even if such male fasteners 30d are discarded, the water-soluble resin 46 is dissolved and disappears by rainwater or the like, and thereby the male fasteners 30d made of biodegradable resin are used.
Since the hole 38d and the groove 34d are formed in the, the decomposing action by microorganisms also proceeds rapidly. The male surface fastener 30d as shown in FIG. 13 is formed by forming a water-soluble resin film in which convex portions corresponding to holes and grooves are formed in advance from a biodegradable resin into a semi-molten male fastener. It can also be formed by press-fitting to the back surface of.

FIG. 15 shows a sixth embodiment of the male surface fastener made of a biodegradable resin of the present invention. The male fastener 30e of this embodiment includes an engagement element 32 from the base 31e.
It has a hole 38e extending toward the point e, and has higher flexibility and a higher decomposition rate by microorganisms. Such a hole 38e is formed, for example, by forming a sharp projection corresponding to the shape of the hole 38e on the male surface fastener 30e in a semi-molten state or a softened state immediately after molding. It can be performed by pressing and laminating the resin film so that the protrusions are embedded therein, and then cooling and solidifying the male surface fastener, and then eluting the water-soluble resin film into an appropriate solvent. .
Further, as another example of the method of forming the holes and / or grooves as described above, a water-soluble resin film in which protrusions and / or protrusions corresponding to the holes and / or grooves are formed in advance in a lower mold is used. A method in which a surface fastener is formed from a biodegradable resin by disposing the film in a cavity and using the water-soluble resin film as a cavity surface of a lower mold can also be adopted.

The water-soluble resin used for forming the groove and / or the hole or as the adhesive layer is a water-soluble resin having a hydrophilic group such as a hydroxyl group, a carboxyl group, a sulfone group and has moldability. Any material can be used, for example, polyvinyl alcohol, modified polyvinyl alcohol, polyacrylic acid, polyethylene oxide, C
MC, gum, etc., among which modified polyvinyl alcohol (e.g., Nippon Synthetic Chemical Industry Co., Ltd.'s Ecomaty AX (polyoxyalkylene grafted onto vinyl alcohol-allyl alcohol copolymer) is preferably used) Can be.

Other biodegradable resins that can be used in combination with the biodegradable resin according to the present invention, if necessary, have moldability, moderate flexibility and hardness, and are affected by the action of microorganisms. Any resin that can be disintegrated can be used. For example, a microbial fermentation production type resin such as Biopol (a copolymer of hydroxybutyric acid and hydroxyvaleric acid) manufactured by Zeneca Corporation, and Materby manufactured by Nippon Synthetic Chemical Industry Co., Ltd. Natural polymer (starch) resins such as Novon manufactured by Warner Lumbard in the United States, chemically synthesized resins such as Praxel (polycaprolactone) manufactured by Daicel Chemical Industries, Ltd., and polylactic acid such as Lacti manufactured by Shimadzu Corporation Is mentioned.

[0025]

EXAMPLES Examples of the effects of the present invention will be described below, but the present invention is not limited to the following examples.

Example 1 As a raw material, a commercially available biodegradable resin and starch were used. In this example, "Bionore"# S1005, which is an aliphatic polyester-based biodegradable resin manufactured by Showa Polymer Co., Ltd., was used as polybutylene succinate, and corn starch manufactured by Japan Food Industry Co., Ltd. was used as starch. Certain COR
N BOY "was used for each. First, these materials were dried at 80 ° C. under reduced pressure for 24 hours. Bionole / corn starch = 90/10, 70/3 by weight ratio of both materials
It was weighed so as to be 0, 50/50, and 40/60, and was put into a kneading device. Kneading temperature 190 ° C, mixer rotation speed 6
After kneading at 0 r / min and a kneading time of 12 minutes, the resins a (90/10), b (70/30), and c (50
/ 50) and d (40/60). Note that the resin e is a single piece of Bionole # S1005. Each of the resins a, b, c, d, and e prepared by the above method was press-molded into a plate having a thickness of 3 mm, and the bending strength and the bending elastic modulus were measured. The results are shown in Table 1 below and FIGS. 16 and 17. From these results, it can be seen that the bending strength and the flexural modulus increase as the amount of added starch increases.

Further, for each of the resins a, b, c, d and e, an injection fastener of 5VS standard was molded by an injection molding machine to obtain each molded fastener A, B, C, D and E.
For each of the molded products A, B, C, D and E, the transverse pull strength was measured. The results are shown in Table 1 below and FIG. The transverse pulling strength was measured as shown in FIG. That is, in the state of the fastener chain 2d in which the engagement teeth 4d are engaged, the fastener chain 2d in FIG.
At a constant speed (300 mm / min) as shown in 9, the tensile resistance of the fastener tape 3d is measured using a tensile tester. Note that the width of the clamp 50 is 25 mm. From the results shown in Table 1 and FIG. 18, it can be seen that the lateral draw strength of the fastener is increased by the addition of starch. When the amount of corn starch is 10 to 50% by weight based on the total weight of the resin material, 25 kgf /
It showed a value exceeding the horizontal pulling strength of 25 mm, and it was confirmed that the strength was greatest when the amount of corn starch was around 30% by weight.

[Table 1]

[0028]

As described above, according to the present invention, the starch portion particles have a two-phase structure in which the polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester is dispersed, and are practically sufficient. A high-strength biodegradable resin molded product is provided, and can be used as products in various fields such as a slide fastener and a hook-and-loop fastener.
Moreover, such a biodegradable resin molded product can be manufactured with good moldability. Further, since the biodegradable resin molded article of the present invention comprises a polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester which is a biodegradable resin, and starch which is a natural polymer compound which is biodegradable. ,
Even when discarded, it is decomposed by microorganisms in the soil and water, and does not cause global environmental destruction or waste pollution. Moreover, products made of biodegradable resin are converted into compost and returned to the earth, so there is no danger of harm to wildlife due to scattered garbage like ordinary plastic products. It also helps to extend the life of the landfill and stabilize it. Furthermore, even if these products are incinerated, the risk of damaging the incinerator is reduced because the biodegradable resin generates less heat when incinerated. further,
The biodegradable surface fastener to which the present invention is applied can be suitably used as a connecting tool for various disposable products such as a binding band and a seedling cover made of a biodegradable resin or a water-soluble resin, an enoki mushroom raising seedling cover, and a diaper. it can.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a slide fastener made of a biodegradable resin.

FIG. 2 is a plan view showing another embodiment of a slide fastener made of a biodegradable resin.

FIG. 3 is a plan view showing still another embodiment of a slide fastener made of a biodegradable resin.

FIG. 4 is a partially broken plan view showing another embodiment of a slide fastener made of a biodegradable resin.

FIG. 5 is a partial perspective view of the first embodiment of the male surface fastener made of a biodegradable resin.

FIG. 6 is a partial cross-sectional view showing an engaged state of the male fastener made of biodegradable resin and the female fastener made of biodegradable resin shown in FIG. 5, wherein the male fastener is taken along line AA of FIG. 2 shows a cross section in the direction.

FIG. 7 is a partial perspective view of a second embodiment of the male fastener made of biodegradable resin.

8 is a partial cross-sectional view showing an engaged state between the male fastener made of biodegradable resin and the female fastener made of biodegradable resin shown in FIG. 7, and the male fastener is viewed from the line BB in FIG. 2 shows a cross section in the direction.

FIG. 9 is a perspective view of a third embodiment of the biodegradable resin surface fastener.

FIG. 10 is a partially broken side view showing a method of engaging the biodegradable resin surface fastener shown in FIG.

FIG. 11 is a partial sectional view of a female surface fastener made of a biodegradable resin according to a fourth embodiment.

FIG. 12 is a partial cross-sectional view of a male surface fastener made of a biodegradable resin according to a fourth embodiment.

FIG. 13 is a partial cross-sectional view showing a state in which a water-soluble resin is laminated on the back surface of the base of the fifth embodiment of the male surface fastener made of a biodegradable resin.

FIG. 14 is a partial sectional view showing a fifth embodiment of the male surface fastener made of a biodegradable resin.

FIG. 15 is a partial sectional view of a sixth embodiment of the male surface fastener made of biodegradable resin.

FIG. 16 shows polybutylene succinate (Bionole #S)
It is a graph which shows the bending strength of the resin of various mixing ratios of 1005) / starch.

FIG. 17: Polybutylene succinate (Bionole #S
It is a graph which shows the bending elastic modulus of the resin of various mixing ratios of 1005) / starch.

FIG. 18: Polybutylene succinate (Bionole #S)
It is a graph which shows the horizontal pulling strength of the slide fastener formed from the resin of various mixing ratios of 1005) / starch.

FIG. 19 is a schematic diagram showing a method for measuring the horizontal pulling strength in Example 1.

[Explanation of symbols]

1, 1a, 1b, 1c Slide fastener 2, 2b, 2c, 2d Fastener chain 3, 3b, 3c, 3d Fastener tape 4, 4b, 4c, 4d Element 5 Slider 6 Lower stop 7 Upper stop 8 Lower stop 9 Reinforcement sheet-like member 10 Separable bottom end fitting 30, 30a, 30b, 30c, 30d, 30e Male surface fastener 31, 31a, 31b, 31c, 31d, 31e, 4
1, 41a Base 34, 34a, 34b, 34d Groove 38b, 38d, 38e Hole 40, 40a Female surface fastener 6 Lower stop 7 Upper stop 8 Lower stop 9 Reinforcement sheet-like member 10 Release fitting 30 , 30a, 30b, 30c, 30d, 30e Male fasteners 31, 31a, 31b, 31c, 31d, 31e, 4
1, 41a Base 32, 32a, 32b, 32c, 32d, 32e Hook-shaped engaging element 34, 34a, 34b, 34d Groove 38b, 38d, 38e Hole 40, 40a Female surface fastener

Claims (4)

[Claims] 1. A biodegradable resin molding made of a resin material obtained by adding starch to a biodegradable resin containing a polybutylene succinate-based and / or polyethylene adipate-based aliphatic polyester as a main component. Goods. 2. The ratio of starch to the total weight of the resin material is 1
The molded article according to claim 1, wherein the amount is 0 to 60% by weight. 3. The molded article according to claim 1, wherein the molded article is a slide fastener. 4. The molded article according to claim 1, wherein the molded article is a surface fastener.