JPH0698635A - Container made of molded biodegradable nonwoven fabric and its forming process - Google Patents

Abstract

PURPOSE:To provide a biodegradable formed container for agricultural and horticultural use, completely decomposable by microorganisms in soil, resistant to decomposition in raising seedling period and quickly decomposable in a state embedded in soil. CONSTITUTION:A nonwoven fabric web to be used as a base material has an areal density of 100g/m<2> and is made of a mixed fiber consisting of 15% water-soluble Vinylon (PVA fiber), 15% rayon and 70% wool. The web is subjected to hot compression forming with a pair of male and female dies heated at 130 deg.C while applying steam of 120 deg.C to the web. The inner side surface of the obtained container is coated with 15g/m<2> of a cellulose acetate resin and the outer side surface is coated with 10g/m<2> of a biodegradable binder consisting of chitosan and cellulose fine particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biodegradable non-woven fabric molding container used in the field of agriculture and horticulture, such as a nursery pot and a plug pot. More specifically, it relates to a nursery period in air. Hard to be decomposed, its strength is maintained,
The present invention relates to a biodegradable non-woven fabric molded container which is rapidly decomposed in soil and finally completely decomposed.

[0002]

2. Description of the Related Art As a seedling raising pot used in the field of agriculture and horticulture, a seedling raising container made of unglazed pot, peat moss, paper, a plastic pot or a nonwoven fabric thermocompressed with a thermoplastic synthetic fiber web (Japanese Patent Application Laid-Open No. Sho-06-29). 57-94225) and the like, and the plug pot uses a wet-molded body (so-called pulp mold) or the like that uses waste paper.
In recent years, demands for plastic molded products (polypots, etc.) made of vinyl chloride and polyethylene have been increasing from the viewpoint of easy handling and price.

[0003]

However, the above-mentioned plastic molded body is treated as industrial waste as a disposal problem after use, and the incinerator itself is damaged due to generation of harmful gas during incineration or high temperature. There are drawbacks.

Furthermore, seedlings grown in such molded containers need to be replanted into large pots or open fields, so-called transplantation, as they grow, but at this time roots are damaged and cause death. However, there is a problem that this manual work becomes enormous.

Further, in pulp-molded products, since waste paper as a raw material contains a substance that inhibits biodegradation such as lignin,
It remains for a long time even after transplanting to the open field, adversely affects root growth (so-called root tension), has too high water absorption, has low water resistance, and has poor shape retention.

The non-woven container made of synthetic fiber is not biodegraded and becomes coarse dust, which causes problems such as generation of harmful gas during incineration and damage to the incinerator.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and 10% by weight to 50% by weight of water-soluble vinylon fiber is contained in the fibers constituting the non-woven fabric as the base material of the molded body. % And 1 or more kinds of fibers selected from viscose other than the above vinylon fibers, recycled fibers such as cuprammonium rayon, animal protein fibers such as wool and silk 9
1 ton / cm ² or more by a pair of concave and convex molds heated by a hot press hot platen at 100 ° C. or more on a substrate nonwoven fabric web or nonwoven fabric mat having a basis weight of 30 g / m ² or more composed of a mixed fiber of 0 to 50% by weight The above problems can be obtained by obtaining a biodegradable non-woven fabric molded container which is formed by wet molding in which steam at a temperature of at least 100 ° C. or more is used at the time of molding, or the mat is preliminarily hydrated before being subjected to heat compression molding at a pressure of Is solved.

Furthermore, in order to control the decomposition period,
During seedling raising in the air, cellulose, acetate resin, or an inorganic antibacterial agent such as zeolite, or an inorganic or aliphatic water repellent agent such as silicon is applied to the inner surface in order to delay the decomposition by the soil contained in the molding container. Biodegradable binder containing chitosan and cellulose as main components or ethyl cellulose and its derivatives, polycaprolactone, hydroxypropyl cellulose, vinyl acetate-vinyl alcohol copolymer having a degree of polymerization of 500 or less, heat having biodegradability A biodegradable thermoplastic resin such as plastic polyvinyl alcohol is applied or sprayed as a plastic that biodegrades for a long period of time, and after transplanting to the open field, etc. Binders alone or with carbohydrates such as corn starch and starch, or vegetable binders such as rice bran. In which to obtain a molding vessel by sparging or coated Park protein or a complex binder to plasticizer mixed in glycerol as biodegradable plastic in a short period of time.

The above-mentioned short-term degradable plastics are those that biodegrade in soil for 1-2 months, and the long-term biodegradable plastics are those that biodegrade in soil over a year. Say.

[0010]

Since the molded container of the present invention has a biodegradable function, it is completely decomposed and eliminated by microorganisms in the soil after use, there is no need to incinerate, and no harmful substances are released or an incinerator. Does not hurt.

Further, it is not necessary to take out the seedlings from the molded body for transplantation, there is no concern that the roots will be damaged and die during the replanting work, and the labor time can be saved. In addition, since it is porous and breathable, the roots of the plant extend in all directions of the container and promote the growth of the plant.

[0012] In particular, since the plastic that biodegrades for a long period of time adheres to the inner surface of the molded container and the plastic that biodegrades for a short period of time adheres to the outer surface, the decomposition is delayed during the seedling raising period, and the molded container It retains its own strength and, after being embedded in the open field, it decomposes and disappears quickly, and can be used without affecting rooting.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below with reference to the drawings.

FIG. 1 (a) is a perspective view showing an example of the biodegradable non-woven fabric molding container of the present invention, FIG. 1 (b) is an enlarged view of the portion a of FIG. 1 (a), and FIG. It is a perspective view of an Example. The non-woven fabric substrate 2 constituting the molding container 1 contains 10% to 50% by weight of the water-soluble vinylon fiber 3, fibers 6 other than the water-soluble vinylon fiber, for example, regenerated fiber such as viscose, copper ammonia rayon, and wool. , A mixed fiber of 90 to 50% by weight of one or more kinds of fibers selected from animal protein fibers such as silk, and the amount of the water-soluble vinylon fiber 3 contained in the non-woven fabric substrate 2 is 10% by weight. If it is less than the above range, other fibers cannot be sufficiently adhered and fixed during molding, and the strength of the molded container cannot be maintained.

On the other hand, if it exceeds 50% by weight, the water-soluble vinylon fiber is formed into a film, and the air permeability and water permeability are lost, which causes root rot. The basis weight of the non-woven fabric substrate 2 may be at least 30 g / m ² or more. If it is less than 30 g / m ² , the molding container itself has no strength and so-called self-supporting property is lost. Further, if the fabric weight becomes excessively large, it becomes dense and loses water permeability and air permeability.

Therefore, the desirable range depends on the size and shape of the molding container, but is 100 (No. 3 to 4) to 300 (No. 7 to 8) g / m ² in the nursery pot and 50 to 150 g in the plug pot. / m ² , but is not limited to these.

Next, the molding method of the present invention is performed by the following steps. When the base nonwoven fabric 2 obtained above is molded, at the time of molding, the water-soluble vinylon fibers contained in the base nonwoven fabric are bonded to other fibers by hot water melting and molded. And a wet molding step of performing thermal compression molding using steam at 100 ° C. or higher at the time of molding or using a water-containing base material in which the base nonwoven fabric contains water.

The water content of the water-containing base material is suitably 10 to 30% by weight based on the weight of the base material, although it depends on the basis weight. The temperature and pressure conditions for maintaining wet molding are 1
It is sufficient if the temperature is 00 ° C or higher and 1 ton / cm ² or higher, and if the temperature is lower than this value, a sufficient molded body cannot be obtained.

A molded product having biodegradability can be obtained by molding with the above-mentioned substrate non-woven fabric and molding conditions, but depending on the kind of plant to be raised, it may take a long period of 1 to 2 months for raising seedlings. Yes, the microorganisms contained in the soil placed inside the molded container decomposes from the inside of the molded container, lowering the strength and causing the container to lose its shape.

Therefore, in order to prevent this, a chitosan salt (lactic acid, lactic acid, etc.) in which an inorganic antibacterial agent such as cellulose acetate resin or zeolite or an inorganic or aliphatic water repellent such as silicon is mixed on the inner surface of the container. Organic acids such as acetic acid 0.5-
Chitosan is adjusted to a concentration of 0.5 to 1.0% in a 1.0% aqueous solution) and fine cellulose is added in a solid content ratio of 20 to 3
Biodegradable binder mixed with 0:80 to 70 or ethyl cellulose and its derivatives, polycaprolactone,
Plastic 4 that biodegrades a biodegradable thermoplastic resin consisting of hydroxypropyl cellulose, a vinyl acetate-vinyl alcohol copolymer having a degree of polymerization of 500 or less, and a thermoplastic polyvinyl alcohol having biodegradability in a long period of time 4
As a result, the decomposition period is delayed by spraying or applying.

The amount of plastic 4 biodegradable over a long period of time is determined by the basis weight of the constituent fibers, the shape, and the seedling raising period. It should be 10 g / m ² in the seedling raising pot shape and 5 g / m ² or more in the plug pot shape. If the object is sufficiently achieved, and the amount is less than the above-mentioned amount, the effect gradually diminishes.

Further, if the mixed solid content ratio of chitosan and fine cellulose of the biodegradable binder containing chitosan and cellulose as main components is out of the above range, sufficient strength and water resistance as a binder cannot be obtained.

When the above-mentioned molded container is transplanted to the open field or the like, the above-mentioned biodegradable binder is used alone or on the outer surface of the molded product so that the molded product is decomposed and disappears rapidly, or cornstarch, carbohydrates such as starch, rice bran and the like. vegetable protein etc., which was constructed as to be sprayed or applied as a biodegradable plastic 5 quickly composite binder and the plasticizer mixed in glycerol, 10 g / m ² the adhesion amount in seedling pots shaped plug It is sufficient if the pot shape is 5 g / m ² or more, and if it is smaller than the above value, the effect is gradually diminished.

Hereinafter, the present invention will be described in more detail with reference to more specific examples and comparative examples.

Example 1 Water-soluble vinylon (SMA2 made by Unitika) 15% of 2d × 35 mm, rayon fiber 2d × 51 mm of 15% and wool (fiber diameter 20-40 μ, length 5-80 mm) 70% were mixed, 100 g / m ^{2 of} basis weight obtained by a known web forming machine
While applying steam of 120 ° C to the non-woven fabric substrate of
Under the conditions of 30 ° C. and a pressure of 3 ton / cm ² , heat compression molding is performed with a concave-convex mold to mold a seedling-growing pot.

Next, 15 g / m ² of cellulose acetate resin (manufactured by Art Plus) is attached to the inner surface of the molding pot, and a biodegradable binder (solid content ratio of chitosan: fine cellulose = 30 :) on the outer surface. 70) was deposited at 10 g / m ² to form a biodegradable nonwoven fabric molded container.

Example 2 A non-woven fabric web having a basis weight of 250 g / m ² obtained in the same specifications as in Example 1 was sprayed with 40 g / m ^{2 of} water to obtain a water-containing substrate at a temperature of 140 ° C. and a pressure of 5 ton / cm ^2. Heat-compression molding with a concave-convex mold into a seedling-growing pot shape. Ethyl cellulose mixed with a zeolite antibacterial agent (concentration: 5% xylene solution) was attached to this inner surface at 15 g / m ² and further biodegradable on the outer surface. Starch as binder (chitosan: fine cellulose: starch =
30:70:10) mixed with a composite binder of 10 g /
A biodegradable non-woven molded container having m ² attached was formed.

Example 3 Water-soluble vinylon 2d × 35 mm 20%, rayon fiber 2d
× 51mm 10%, wool (20-40μ, 15-80m
m) While spraying steam at a temperature of 120 ° C. onto a nonwoven fabric web with a basis weight of 50 g / m ² composed of 70% mixed fibers,
Thermocompression molding at 30 ° C and pressure of 1.5 ton / cm ² , molded into a plug pot shape, with 10 g / m ² of cellulose acetate resin adhered to the inner surface, and a biodegradable binder (chitosan: fine) on the outer surface. Cellulose = 30:70) 5 g / m ²
Was adhered to obtain a biodegradable nonwoven fabric molded container.

Comparative Example 1 Water-soluble vinylon 2d × 35 mm 5%, rayon fiber 2d ×
51mm 25%, wool (20-40μ, 15-80mm)
10 g / m of cellulose acetate resin was applied to the inner surface of a pot-shaped molding container obtained by thermocompressing a non-woven fabric web having a basis weight of 110 g / m ² made of 70% mixed fibers under the same conditions as in Example 1. ² Attach and further 10g / biodegradable binder (chitosan: fine cellulose = 30:70) on the outer surface
m ^{2 was} adhered to obtain a molded container.

Comparative Example 2 A water-containing substrate obtained by adding 20% by weight of water to the nonwoven web obtained in Example 2 was used to obtain a temperature of 70 ° C. and a pressure of 800 kg / cm ^2.
Then, the same resin as in Example 2 was applied to the inner and outer surfaces of the pot-shaped molding container obtained by heat compression molding using a concave-convex mold to form a molding container.

Comparative Example 3 A base nonwoven fabric formed by adhering 20 g / m ² of ethyl cellulose to a nonwoven fabric web having a basis weight of 20 g / m ² obtained in the same specifications as in Example 3 was thermocompression molded into a plug pot shape. Plastic was applied to the inner surface and the outer surface of this molding pot in the same manner as in Example 1 to obtain a molding container.

Regarding the 6 kinds of seedling raising pots obtained in Examples 1 to 3 and Comparative Examples 1 to 3, moldability, shape retention, degradability during seedling raising and in soil, air permeability, water permeability, plants Table 1 shows the results of an investigation of the degree of impact on (Zinnia)
Shown in.

[0033]

[Table 1]

A commercially available poly pot and a pulp mold plug pot were also compared and examined.

As a result of the above, each of the examples has excellent moldability, shape retention, breathability, and water permeability, and therefore has no effect on plants and is not sufficiently suitable for raising seedlings. It has been found that it has a decomposition period and, when embedded in soil, decomposes and disappears quickly.

[0036]

According to the present invention having the above-mentioned constitution,
A biodegradable nonwoven fabric for agricultural and horticultural use, which can be molded by heat, does not decompose during the period required for raising seedlings, and decomposes rapidly when embedded in soil, can be obtained. Therefore, there is no need to incinerate, release from harmful substances, damage to the incinerator, etc., and there is no risk of pollution of the natural environment. Furthermore, it does not require complicated operations such as transplantation, which is an essential element for synthetic resin systems such as so-called polypots, and does not damage the roots, so it does not have to worry about poor growth or death. Is to have.

[Brief description of drawings]

FIG. 1 (a) is a perspective view of a biodegradable nonwoven fabric molded container of the present invention, and FIG. 1 (b) is an enlarged configuration view of part a of FIG. 1 (a).

FIG. 2 is a perspective view showing another embodiment.

[Explanation of symbols]

 1 Biodegradable Nonwoven Fabric Forming Container 2 Base Nonwoven Fabric 3 Water-Soluble Vinylon Fiber 4 Long-term Biodegradable Plastic 5 Short-term Biodegradable Plastic 6 Fibers Other than Water-soluble Vinylon Fiber

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location D04H 1/42 P 7199-3B 1/58 Z 7199-3B (72) Inventor Jun Hosokawa Takamatsu, Kagawa Prefecture 2-3-3 Hananomachi, Hananomachi, Ichi, Japan Shikoku Institute of Industrial Technology (72) Inventor Takamasa Kubo 2-3-3, Hananomiyacho, Takamatsu, Kagawa Pref., Shikoku Institute of Industrial Technology (72) Inventor Yoshihara, 1st year, 2-3-3 Hananomiyacho, Takamatsu city, Kagawa prefecture, Shikoku Institute of Industrial Technology (72) Inventor, Mutsuo Nakagawa, 1-21-15, Seifu, Takarazuka-shi, Hyogo prefecture ( 72) Inventor Teruhiro Komatsu 2-4-4 Mukotoyocho, Amagasaki City, Hyogo Prefecture 50-306 (72) Inventor Shozo Mimura 4-46-8 Ogino City, Itami City, Hyogo Prefecture

Claims (5)

[Claims] 1. Water-soluble vinylon fiber 10% by weight to 50
% By weight and one or more kinds of fibers 90 to 5 selected from viscose other than the vinylon fiber, recycled fiber such as cuprammonium rayon, animal protein fiber such as wool and silk
A long-term biodegradable plastic is adhered to the inner surface of a molding container obtained by thermocompressing a base material non-woven web or non-woven mat having a basis weight of 30 g / m ² or more composed of a mixed fiber with 0% by weight, A biodegradable non-woven fabric molded container characterized by having a biodegradable plastic attached to the outer surface in a short period of time. 2. As a plastic that biodegrades for a long period of time, cellulose acetate resin, chitosan mixed with an inorganic antibacterial agent such as zeolite or copper, or an inorganic or aliphatic water repellent such as silicon and fine cellulose are used. The biodegradable nonwoven fabric molding container according to claim 1, which is a biodegradable binder as a main component or a thermoplastic resin having biodegradability. 3. As a plastic which is biodegradable in a short period of time, a biodegradable binder containing chitosan-cellulose as a main component alone, a carbohydrate such as corn starch or starch, or a vegetable protein such as rice bran or a plasticizer such as glycerin. The biodegradable nonwoven fabric molding container according to claim 1 or 2, which is a mixed binder. 4. The biodegradable thermoplastic resin according to claim 2, wherein ethyl cellulose and its derivatives, polycaprolactone, hydroxypropyl cellulose, and a degree of polymerization of 5 are used.
The biodegradable non-woven fabric molding container according to claim 1 or 2 or 3, wherein the vinyl acetate-vinyl alcohol copolymer of 00 or less and a thermoplastic polyvinyl alcohol having biodegradability. 5. Water-soluble vinylon fiber 10% by weight to 50
% By weight and viscose other than the vinylon fiber, regenerated fiber such as cuprammonium rayon, and animal protein fiber such as wool and silk 90 to 5
When a base nonwoven fabric web or a non-woven fabric mat made of mixed fibers with 0% by weight is subjected to heat compression molding at a pressure of 1 ton / cm ² or more by a pair of concave and convex molds heated to 100 ° C. or higher by a hot press hot platen, A method for molding a biodegradable non-woven fabric molding container, which comprises using steam at a temperature of 100 ° C. or higher at the time of molding or wet-molding the substrate non-woven web or mat after preliminarily containing water.