JPH0892006A - Biodegradable resin molded product containing biologically active substance - Google Patents

Abstract

PURPOSE: To obtain various molded products having sufficient thermal stability and mechanical strength on practical uses, a little in the quantity of combustion-generated heat or not having the fear of environmental pollution even when wasted, capable of being easily wasted, and having a property for slowly releasing physiologically active substances. CONSTITUTION: The biodegradable resin molded product is produced by adding a biologically active agent such as a herbicide, an antifungal agent, an antibacterial agent, an insecticide or a repellent to a biodegradable resin, e.g. an aliphatic polyester resin, polylactic acid resin, polycaprolactone resin, polyvinyl alcohol or starch. The biologically active substance may directly be kneaded with the biodegradable resin, but in some cases, after the biologically active substance is advantageously impregnated or adsorbed into a porous substance having an average particle diameter of 0.01-100μm, especially 0.1-30μm, in relation to the evaporation property of the biologically active substance, the melting point of the resin, the processing temperature, etc. The biologically active resin is especially preferably an aliphatic polyester resin produced by synthesizing a polyester prepolymer having a relatively high mol.wt. from a glycol and an aliphatic dibasic acid as main components and subsequently converting the prepolymer into a high polymer with a coupling agent.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an environment in which a biodegradable resin, which is degradable in soil that does not pollute soil, rivers, seas, etc., is used as a carrier for bioactive substances when it is disposed of after use. The present invention relates to a biodegradable resin molded article containing a biologically active substance that is friendly to water.

[0002]

2. Description of the Related Art Conventionally, particles or powders obtained by impregnating or adsorbing bioactive substances such as insecticides and bactericides into porous substances, and further, these particles and powders are generally used for polyethylene, polypropylene, polyvinyl chloride, polyamide, etc. The use as a granular material or a molded product by kneading with a resin or a general-purpose engineering plastic is disclosed in, for example, JP-B-58-33103, JP-A-4-74101 and JP-A-5-74101.
The proposal is made in -176976 and the like.

In these proposals, what is impregnated with or adsorbed on an inorganic powder or granular material such as zeolite, hay, clay or the like is a powder or granular material although it does not contaminate soil or seawater itself. Therefore, it is not only limited in application, but because bioactive substances are simply impregnated or adsorbed, they easily release bioactive substances when they encounter rainwater, moisture in the atmosphere, sunlight, etc. ,
It is unavoidable to create an environment above the required concentration of the active substance and consume the life in a short period of time.

On the other hand, the surface of the bioactive substance is covered with plastic or the like by directly kneading or coating the plastic such as polyethylene with the bioactive substance or by once impregnating or adsorbing the porous substance and then kneading. Therefore, the sustained release property (slow release property) of the bioactive substance is ensured and the shape stability is imparted, and the bioactive substance is applied to various fields.

As a result, the sustained release property is not impaired even when rainwater is encountered, and the shape stability of the molded article itself can be maintained. In this case, in order to impart a covering material or shape stability. Since the plastics such as polyethylene used are not biodegradable, it is necessary to collect these molded bodies after the expiration of their effective period or after use, and reuse or incinerate them. It may be possible to recover to some extent if it is a large-sized molded product that can be easily recovered, but it is extremely difficult or impossible to recover it with a fine shape.

In ordinary citizen life, a molded product, a small particle-shaped molded product or a film containing a useful bioactive substance and having a slow release property and requiring a shape such that it is thrown away once each time. Although there is a demand for a shaped or fibrous shaped product, a bioactive substance-containing resin composition suitable for this has not been proposed yet.

[0007]

DISCLOSURE OF THE INVENTION The present invention has practically sufficient thermal stability and mechanical properties typified by tensile strength, and has a small combustion calorific value even if it is incinerated after use. Or even if it is discarded after use, there is little risk of environmental pollution and it is easy to discard herbicides, fungicides,
It is an object of the present invention to provide various molded products having a slow release property of bioactive substances such as insect repellents, bactericides and repellents.

[0008]

The present invention provides a biodegradable resin containing a bioactive substance such as a herbicide, an antifungal agent, a fungicide, an insect repellent, and a repellent. The above object was achieved by developing a biodegradable resin molded product containing the same.

In the present invention, the biodegradable resin means, for example, poly-3-hydroxybutyric acid ester (hereinafter referred to as PH
B), curdlan (a kind of polysaccharide), pullulan, (water-soluble polysaccharide), sugars such as cellulose, starch, amylose and chitin, proteins such as gluten and gelatin, collagen, fermented polyamino acid, synthetic polyamino acid, Cellulose acetate, polycaprolactone (poly-ε-
Caprolactone <hereinafter, PCL>), polylactic acid, polyglycolide, poly (3-hydroxybutyrate), polyvinyl alcohol (hereinafter PVA), EVOH, polylactide, polypropiolactone, produced by combining various glycols and dicarboxylic acids Aliphatic polyester (for example, ethylene glycol to oxalic acid-based, 1,
4-butanediol-oxalic acid system, ethylene glycol-succinic acid system, 1,4-butanediol-succinic acid system,
1,4-butanediol to succinic acid to adipic acid, etc.), polyethylene glycol, polypropylene glycol, etc., and starch, PVA, starch, PVA, PCL, etc.
Examples include blends of more than one kind.

The biodegradable resin used in the present invention may be of any type as long as it has the above-mentioned biodegradability, but molding processability, biodegradability, slow release property, price, mechanical properties and the like are taken into consideration. Then, an aliphatic polyester resin obtained by synthesizing a polyester prepolymer having a relatively high molecular weight mainly from glycol and an aliphatic dibasic acid or a derivative thereof and then polymerizing these prepolymers with a coupling agent is most preferable.

Polyester prepolymers for obtaining biodegradable aliphatic polyester resins include glycols such as 1,4-butanediol and ethylene glycol, and aliphatic dibasic acids such as oxalic acid, succinic acid, and adipic acid, or the like. The terminal group obtained by reacting with the derivative is substantially a hydroxyl group and has a number average molecular weight of 5,000 or more,
A saturated aliphatic polyester prepolymer having a relatively high molecular weight of 10,000 or more and a melting point of 60 ° C. or more is preferable.

In this case, as the raw material, glycol and aliphatic dibasic acid or its derivative are mainly aliphatic, but a small amount of other components such as trifunctional or tetrafunctional polyhydric alcohol, oxycarboxylic acid and It may be a combination of polyfunctional components such as polyvalent carboxylic acids or acid anhydrides thereof. In order to synthesize a relatively high molecular weight polyester prepolymer, a deglycolization reaction catalyst such as a titanium compound such as an acetoacetoyl type titanium chelate compound or an organic alkoxytitanium compound is used in the deglycolization reaction following the esterification. It is necessary to. As the polyester prepolymer, one having a number average molecular weight of usually 5,000 or more, preferably 10,000 or more and a melting point of 60 ° C. or more can be easily obtained, and it is more preferable if it has crystallinity.

In order to obtain a preferable aliphatic polyester resin, a polyester prepolymer having a number average molecular weight of 5,000 or more, preferably 10,000 or more, whose end groups are substantially hydroxyl groups, is further added. In order to increase the temperature, diisocyanate, oxazoline, diepoxy compound, acid anhydride, etc., especially diisocyanate coupling agent is used.

The amount of the coupling agent added is 0.1 to 5 parts by weight, based on 100 parts by weight of the polyester prepolymer.
It is preferably 0.5 to 3 parts by weight. The addition is preferably carried out under conditions where the polyester prepolymer is in a uniformly molten state and can be easily stirred. The aliphatic polyester thus obtained has a number average molecular weight of 10,000 or more, which makes it possible to obtain sufficient mechanical properties as a polyester resin and a polyester resin composition.

Among these, the MFR value at 190 ° C. is 0.1 to 500, depending on the application and the molding method.
g / 10 min, a crystalline resin, and a resin having a melting point of more than 70 ° C. is preferable, and more preferably, MFR is 0.2 to 300 g / 10 mi.
n is preferable, most preferably MFR is 0.2 to 1.
00g / 10min.

If the MFR is less than 0.1 g / 10 min, it is difficult to shape by various molding methods including granulation, which is not preferable. On the other hand, MFR is 500g / 10
If it exceeds min, not only the mechanical strength is extremely lowered, but also granulation for producing granules becomes very difficult. In addition, the melting temperature of the resin is 70 ° C or higher, preferably 75 ° C.
It is desirable that the temperature is ℃ or higher. If the melting temperature is less than 70 ° C, or if it is loaded on the bottom of the ship when exporting, the temperature will be 60 ° C.
If it rises to a certain degree, there is a risk of softening and fusion. Further, when it is used as a granular material, it is not a serious problem, but in the case of various molded products such as films and injection molded products, the field of use is limited due to the problem of heat resistance, which is not preferable.

Examples of the bioactive substance include herbicides, antifungal agents, insect repellents, fungicides, antifungal (bactericidal) agents, repellents, acaricides and nematicides. For example, paradichlorobenzene, naphthalene, camphor, pyrethroid, octachlorodipropyl ether, insecticides such as hinokitiol, o-phenylphenol (OPP), diphenyl, 1,2-bis (bromoacetoxy) ethane,
Cinnamaldehyde, phenyl acetate, allyl isothiocyanate, α-methylacetophenone, thymol, perchlorocyclopentadiene, bromacetic acid, 2,2-dibromo-3nitrilepropionamide, ethyl chloroacetate, butyl chloroacetate, methyl chloroacetate, 5 Examples include antifungal agents and antibacterial agents such as -chloro-2-methylisothiazolin-3-one and glutaraldehyde.

Further, for antibacterial purposes, metal ions such as silver, copper and zinc, quaternary ammonium salts, natural products such as hinokitiol and the like can be mentioned. Also, herbicidal active substances such as ammonium glufosinate, glyphosate, bialaphos, active substances from phenoxy type such as CMPP, MCPA, 2,4-D, phenoxyphenoxy type such as diclofopmethyl or phenoxa. Active substances from the heteroaryloxyphenoxy system such as propethyl, phenoxaprop-P-ethyl, active substances from the urea system such as isoproturon, diuron, linuron, monolinuron and chlorthuluron, amidesulfuron, Tribenuron (DPX-L530
0), thiamethuron-methyl (DPX-M631
6), metsulfuron-methyl (DPX-T637)
6), active substances from a system consisting of sulfonylureas such as primisulfuron-methyl and nicosulfuron,
Actives from a system consisting of triazines such as atrazine or simazine, actives from a system consisting of imidazolinones such as imazapeal, imazaquin, imazetapeal and imazametabenz, and diphenyl ether derivatives such as acifluorfen, fluoroglycophene, Lactofen and bifenox, dicotylene herbicides such as ioxynil, bromoxynil, dicamba, diflufenican, fluroxypeal,
Fenmedifam, desmedifam, bentazone, metamitron, metribuzin, chloridazone, etofumesate or the active substance trifluralin, e.g. EP-A-86750, 94349, 1st.
No. 91736, No. 346620, No. 333131
No. 269806, No. 159290, No. 2
546845, PCT / EP-90 / 02020 and PCT / EP-90 / 01966; fungicidal active substances such as azoles such as triadimefone, cyproconazole, microbutanyl and diclobutrazol. From the system consisting of dithiocarbamates such as maneb, zineb and mancozeb, benzimidazoles such as carbendazim, or procymidone, iprodione, vinclozolin, thiophanate-methyl, simoxanil, Active substances such as folpet, copper oxychloride, sulfur or TPTH; from systems consisting of pyrethroids such as deltamethrin, acrinathrin, tralomethrin, permethrin and dipermethrin Substance, the active substance from benzoyl urea such as diflubenzuron or e.g. endosulfan, an active substance, such as pirimicarb or silafluofen.

These bioactive substances may be directly kneaded with the biodegradable resin, but once the bioactive substance is converted into a porous substance due to the volatility of the active substance, the melting point of the biodegradable resin and the processing temperature. It may be advantageous to knead after impregnation or adsorption. Among biodegradable resins, a high-flow type and low melting temperature, for example, when kneading a solid bioactive substance such as an aliphatic polyester having a melting point of 70 to 80 ° C., a side-feed method (mainly A method of feeding an active substance from a position close to a die of a twin-screw extruder) or the like causes vaporization during kneading to some extent, but there is no big problem, but a relatively volatile agent such as a viresuloid drug is used. Most of liquid bioactive substances and bioactive substances that are highly sublimable even in solid form are vaporized, and the effect is halved, which is a problem. Therefore, it is possible to solve the above problem by adsorbing it to a porous substance having an adsorbing ability such as zeolite and then kneading and dispersing it in the biodegradable resin.

The porous substance having an adsorptivity as referred to herein has an average particle size of 0.01 to 200 μm, preferably 0.05 to 80 μm, more preferably 0.1 to 200 μm.
Particles of 50 μm, optimally 0.1 to 30 μm. When the average particle size is less than 0.01 μm, it is not preferable in terms of aggregation, handling, kneading / dispersion with resin, and cost. On the other hand, when it exceeds 200 μm, the mechanical properties of the kneaded resin are deteriorated and it becomes difficult to coat the granular material, which is not preferable. Specific examples of the porous substance include zeolite, calcium phosphate, calcium carbonate (including crushed products such as coral fossils and shells), and aluminum hydroxide, talc, alumina, barium carbonate, barium sulfate, calcium carbonate, phosphorus. Acid tricalcium diphosphate, calcium hydrogen phosphate, magnesium oxide, silica gel, magnesium sulfate, magnesium hydroxide, silicon oxide, and metal oxides such as silicon oxide having a hydroxyl group or metal hydroxides alone or in mixture, or acid clay, Examples include silica soil, activated clay, and activated carbon. Further, in addition to the above inorganic porous substances, one or more organic porous substances such as starch, carboxymethyl cellulose, carbohydrates such as wood flour and wheat straw can be used.

[0021] For example, with respect to a bioactive substance such as a bilethroid drug, which is a volatile liquid, most of the components are vaporized during the kneading, and the efficacy is significantly reduced, which is a problem.
Therefore, when the bioactive substance is volatile, the porous substance having adsorption ability such as zeolite described above is put into the active substance and stirred, or when the active substance is a solid, the active substance is used as a solvent (generally Specifically, it is dissolved in ethyl alcohol, isopropyl alcohol, or water), and the active substance solution is adsorbed by adding the porous substance having adsorption ability such as zeolite described above to the mixture and stirring it, and then adsorbing it in the biodegradable resin. It is advantageous to knead and disperse. Further, an active substance that is liquefied by kneading, such as a combination of orthophenylphenol and naphthalene, may be treated as a liquid active substance.

In this way, the porous substance having adsorbed the active substance is mixed into the biodegradable resin. However, the porous substance having adsorbed the active substance is simply mixed with the biodegradable resin powder. It may be mixed with particles and shaped into various molded bodies by various molding processing methods, and once the porous material with the active substance adsorbed is melt-kneaded with the biodegradable resin, various molding processing methods are used. It may be shaped into a molded product or used as a granular material. Further, various biodegradable resin molded articles obtained by forming a porous material having an active substance adsorbed therein into an emulsion or solution-like coating material together with a biodegradable binder resin and shaping the coating material into various forms by various molding processing methods. The surface or the surface of an organic material such as wood may be coated.

The biodegradable resin obtained by kneading or coating a bioactive substance such as a herbicide, an antifungal agent, an insect repellent, a bactericide or a repellent according to the present invention is used for calender molding, T-die molding, circular die molding (inflation). Molding, foam molding, inflation simultaneous biaxial stretch molding),
Injection molding, blow molding, stamping method, pipe molding,
Shaped into various product shapes by various molding processing methods such as profile extrusion molding, monofilament molding, multifilament molding, non-woven fabric molding such as melt blown molding, and granulation molding.

When it is used as a granular material, its average particle diameter is preferably 3.0 mm or less, more preferably 2.5 mm or less, and preferably 1.0 mm or less. If the average particle size exceeds 3.0 mm, the biodegradation rate becomes slow, which is not preferable. On the other hand, when it is less than 50 μm, it is not preferable from the viewpoint of handling and manufacturing equipment. Although various methods are possible for producing this mini-pellet, it is desirable to use a commercially available underwater-cut type mini-pellet producing apparatus whose finished shape is nearly spherical, but when the bioactive substance is water-soluble, it is hot. In some cases, a cut or mist cut type mini-pellet manufacturing equipment may be preferable.

For example, in the case of Bionore # 1020 (biodegradable aliphatic polyester) manufactured by Showa High Polymer Co., Ltd. with MFR = 20 g / 10 min, the resin temperature in the case of injection molding depends on the molding processing method and product shape. Is 130-25
The temperature is 0 ° C, preferably 160 to 230 ° C. If the temperature is lower than 130 ° C, the viscosity is too high and various moldings are difficult, and if the temperature exceeds 250 ° C, the resin deteriorates, which is disadvantageous.

When blown film molding is performed by using Bionore # 3001 (biodegradable aliphatic polyester) manufactured by Showa High Polymer Co., Ltd. with MFR = 1.2 g / 10 min, it depends on the molding machine and product width / thickness. , The resin temperature is 160 to 250 ° C., preferably 170 to 230 ° C.
Is. If the temperature is lower than 160 ° C, the viscosity is too high to make various moldings difficult. If the temperature exceeds 250 ° C, not only are the bubbles unstable and it is difficult to form a film, but also the resin deteriorates, which is disadvantageous. As an example of modified PVA / starch-based biodegradable plastic, A1 sold by Nippon Synthetic Chemical Industry Co., Ltd.
Also in the case of 05H, the resin temperature is 120 to 180 in the case of injection molding, depending on the molding method and the product shape.
C., preferably 140 to 170.degree. If the temperature is lower than 120 ° C, the viscosity is too high and various moldings are difficult, and if the temperature exceeds 180 ° C, the resin deteriorates, which is disadvantageous. In addition, it is preferable to consider the injection pressure to be slightly higher and the runner gate to be slightly thicker.

In addition, as an example of poly-ε-caprolactone (PCL), TONE P-78 manufactured by UCC Co.
In the case of 7, depending on the molding method and product shape,
In the case of monofilament molding, the resin temperature is 140 to 2
20 degreeC, Preferably it is 160-200 degreeC. 140 ° C
If it is less than 220 ° C, the viscosity is too high and various molding is difficult, and 220 ° C
If it exceeds, there is a disadvantage that the resin deteriorates. Also,
The crystallization temperature is about 22 ° C., which is very low unlike ordinary resins, so the point at the time of molding is how efficiently cooling and crystallization are performed in the molding stage. As an example of biopolyester, poly (3HB-
Co-3HV) copolymer HV fraction 5% D300G (melting point 162 ° C., MFR = 8 g / 10 min) and the like are also suitable.

There are various shapes of molded articles depending on the intended use of the bioactive substance. For example, when applying a herbicide for agricultural land, non-agricultural land, etc., or as a fungicide for agricultural land, sandbox, etc. When applying, or when applying a repellent for preventing the intrusion of dogs, cats, etc. into the garden etc., granular,
It may be a film-shaped or rod-shaped molded product, and even with the same bactericide, a net-shaped molded product in the draining corners of kitchens and bathrooms, etc. Simple costume case,
Various shapes can be considered for the shape of the molded product, such as being mixed with a leisure sheet used as an insect repellent for camping and the like.

The molded articles to which the present invention is applied are
Due to the disappearance of the effects of bioactive substances and the nature of biodegradable resin, it should be applied to disposable type products or products that are discarded after 1 to 2 years of use, such as in landfill after use. The feature is that it does not remain in the soil forever, decomposes and disappears in a short period of time, and can maintain the environment. The molded article of the present invention may, of course, optionally contain a lubricant, a wax, a colorant and the like, but it is premised that the degradability is not adversely affected and it is necessary to confirm.

[0030]

The granular material containing the insect repellent, the fungicide and the bactericide of the present invention has a problem of propagation of various bacteria such as Escherichia coli, which has become a big social problem in recent years. This can be a solution to the problem that a lot of bacteria such as Escherichia coli propagate due to the temperature, which causes health problems to those who play there. Currently, the application of low-density polyethylene and vinyl chloride resin-based insect repellents, fungicides, and granules containing bactericides is under consideration.
Since these resin particles do not decompose, they are scattered in the environment and continue to pollute the environment for a long time.

As another problem, in the case of these non-decomposable resins, biologically active substances such as insect repellents, fungicides and bactericides kneaded inside the granular materials are wasted except those existing near the surface. Expected to become. On the other hand, in the case of the present invention, since the bioactive substances existing inside the particulate matter are sequentially exposed to the surface along with the decomposition of the biodegradable resin, the effect continues for a long time, and the contained bioactive substances all act effectively. In addition to this, the biodegradable resin eventually decomposes and does not remain in the environment. Although the absolute value of the biodegradation rate changes depending on environmental conditions and the like, the rate can be controlled by selecting the biodegradable resin in a timely manner. This point is a great feature in practice. For example, ICI Biopol, Showa High Polymer Co., Bionore 1000 type, 2000 type, 300 type
If the 0 type, the 5000 type and the 6000 type are used, it is possible to design the most suitable one according to the purpose.

Further, as an application example of herbicides, repellents, etc., by reducing the diameter of the granules to preferably about 0.5 to 1 mm, it is possible to spray the herbicides on bunker or the like on the golf course or on the green. Can be used for repellent spraying. In this case, compared to the case of directly spraying the chemicals, the additives (herbicides, repellents, etc.) can be reduced to about 1/3 to 1/30, and there is a possibility that the recent problems of agricultural chemicals on the golf course can be reduced. Also,
Needless to say, after the effect disappears, it gradually decomposes and does not place a large load on the environment. Other than that, it can be used for roadsides such as highways and civil engineering works, spraying herbicides and repellents on parking lots, etc. On the other hand, as an application example of a herbicide, an antifungal agent, an insect repellent, etc., use in the agricultural field is considered. Antifungal agent, agricultural mulch film of the present invention containing insect repellent, fruit tree reinforcement (splinting),
Various flower pots (pots) are fields in which the effects can be expected.

It is one of the good examples to process into various molded products having degradability and to use them. For example, antibacterial non-woven fabric,
Antibacterial brush, weeding function film, antibacterial wallpaper, antifungal drainage corner, antibacterial filter (for air conditioning, vacuum cleaner, etc.)
Are just a few applications. In recent years, MRS
The problem of nosocomial infections due to various bacteria such as A is not limited to hospitals, and has become a problem in various public facilities and homes. It is considered that the present invention can be a solution to this problem. Personal items such as curtains and blinds (wet tissues, slippers, shoe linings, diaper covers, sheets, pillowcases, table cloths, stationery and office supplies (charts, chart cases, files, binders, medical examination cards, X-ray film storage) Non-durable consumable materials such as bags, notebooks, book covers, etc.) and various filters) are considered as specific applications. In addition to biodegradability, these applications are also characterized by a low combustion calorific value, making it easy to incinerate.

[0034]

EXAMPLES The present invention will be described below with reference to examples and comparative examples. (Example 1) and (Comparative Example 1) 100 g of antibacterial calcium phosphate powder in which silver ions are ion-exchanged and adsorbed on calcium phosphate having an average particle diameter of 2 μm and a specific surface area of 2 to 3 m ² and silver is immobilized, and Bionore manufactured by Showa High Polymer Co., Ltd. # 3060 (MFR = 65g / 10min) 1
After premixing 0 kg with a tumbler, pelletizing was performed at a resin temperature of 160 ° C. with a single screw extruder having a screw diameter of 40 mmφ to obtain pellets having a diameter of about 1.0 mm.

The antibacterial properties were tested as follows. Test bacterium: Escherichia coli In an Erlenmeyer flask containing 100 ml of phosphate buffer, 0.2 g of the above pellet was added to 40 g of sea sand on the Kujukuri coast of Chiba prefecture.
1 ml of 10 ⁵ cells / ml of E. coli was added and permeated at 25 ° C., and the number of bacteria was measured over time (the initial number of bacteria was 6.0 × 1.
0 ⁵ cell / ml). The number of bacteria after 10 hours is 12 cels
It was reduced to 1 / ml. On the other hand, when only the bionole pellets were added without adding the antibacterial calcium phosphate powder, it was 1.4 × 10 ⁶ cells / ml. Also,
For comparison, 100 g of the sea sand was added with 1.0 g of the pellet, the maximum water content was 50% and the water content was kept at 25 ° C., and after 5, 10, 20, 40, and 60 weeks, chloroform was added to Bionore # 3060. It was extracted and quantified by HPLC (high performance liquid chromatography) to evaluate the degradability.

[0036]

[Table 1]

(Example 2) and (Comparative Example 2) Bionore # 1060 (MFR = 68 g) manufactured by Showa High Polymer Co., Ltd.
The same test as in Example 1 and Comparative Example 1 was performed, except that / 10 min) was used. Initial number of bacteria is 4.0 x 10 ⁵ c
The cell count after 10 hours was 5 cell / ml. When only bionole was added without adding the antibacterial calcium phosphate powder, 1.9 × 10 ⁶ c
It was ell / ml. The degradability was as follows.

Comparative Example 3 Showa Denko LDPE (MF
R = 20 g / 10 min, density 0.922 g / cm ³ )
The same tests as in Example 1 and Comparative Example 1 were carried out except that was used. The initial bacterial count was 5.0 x 10 ⁵ cells / ml,
The cell count after 10 hours was 8 cells / ml. Also,
When only LDPE was added without adding the antibacterial calcium phosphate powder, it was 1.2 × 10 ⁶ cells / ml. In addition, no degradability was observed.

[0039]

[Table 2]

(Example 3) The antibacterial calcium phosphate pellets used in Example 2 were dry blended 1: 1 with the base resin used therein, and an injection molding machine having a mold clamping pressure of 100 t and a maximum injection capacity of 250 cc was used. Use, resin temperature 1
At 60 ℃, about 200g drainage corner and about 70g
The tray was molded. There was no problem in moldability in both cases. On the other hand, the initial concentration of 1.3 ×
As a result of adding 10 ⁴ Staphylococcus aureus and confirming the state after 24 hours at 35 ° C., the number was reduced to 12.
Further, the tray and the draining corner were stored in red-yellow soil (Nagoya Agricultural Experiment Co., Ltd.) at a temperature of 25 ° C. and a maximum water content of 50%, and the degradability was evaluated. As a result, 35% was decomposed after 40 weeks and 60% was decomposed after 60 weeks.

(Comparative Example 4) The same thing as in Example 3 was carried out using a bionole containing no antibacterial calcium phosphate pellets. As a result, 1.2 × 10 ⁴ was almost unchanged, and no antibacterial property was observed. . In addition, the tray and the draining corner were placed in red-yellow soil (Nagoya Agricultural Experiment Station) at a temperature of 25 ° C.
It was stored at a maximum water content of 50% water content and evaluated for degradability.
As a result, 50% was decomposed after 40 weeks and 75% was decomposed after 60 weeks.

[0042]

EFFECTS OF THE INVENTION A molded article formed from the biodegradable resin of the present invention and having a slow release property of a bioactive substance has biodegradability when embedded in soil or the like, and is decomposed in a short period of time, and therefore is environmentally friendly. Load is small, and even if incinerated, the calorific value of combustion is lower than PP, LDPE, and HDPE.
It is useful for various molded products.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasushi Ichikawa 3-2 Chidori-cho, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture Showa Denko KK Kawasaki Plastics Research Laboratory (72) Inventor, Jun 3 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture -2 Showa Denko KK Kawasaki Plastics Research Laboratory (72) Inventor Takashi Fujimaki 634-4-442 Noba-cho, Konan-ku, Yokohama-shi, Kanagawa

Claims (3)

[Claims] 1. A biodegradable resin, a herbicide, an antifungal agent,
A biodegradable resin molded product containing a bioactive substance, which is characterized by containing a bioactive substance such as a bactericide, an insect repellent, and a repellent. 2. A bioactive substance having an average particle size of 0.01 to 10
A biodegradable resin molded article containing the bioactive substance according to claim 1, which is blended with a biodegradable resin after being impregnated or adsorbed with a 0 μm porous substance. 3. The biological activity according to claim 1, wherein the biodegradable resin is one of an aliphatic polyester resin, a polylactic acid resin, a polycaprolactone resin, polyvinyl alcohol, starch, or a mixture of two or more thereof. Biodegradable resin molded products containing substances.