JPH05199818A - Biodegradable nursery pot - Google Patents

Abstract

PURPOSE:To obtain a cylindrical or square pot, having specific dimensions, made of a material of a biodegradable aliphatic polyester compound (modified material) and suitable for cultivating tomatoes, cabbages, etc., and good in biodegradability. CONSTITUTION:The objective cylindrical or square nursery pot, having a film thickness within the range of 50-200mum, a diameter within the range of 3-8cm or a length of one side within the range of 3-10cm and a height within the range of 3-15cm and made of a material of a biodegradable aliphatic polyester compound (modified material). Furthermore, the modified material is preferably a polymer prepared by modifying the aliphatic polyester compound with <=10wt.% diisocyanate compound.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a nursery pot for agricultural and horticultural purposes. More specifically, it relates to a biodegradable pot for raising seedlings, which requires degradability.

[0002]

2. Description of the Related Art Recently, with the progress of agricultural technology, the method from seed planting to growing seedlings is carried out in a controlled facility such as a vinyl house, and after obtaining excellent seedlings, this is transplanted to the actual field. Is being performed. Most pots conventionally used for this purpose are made of non-biodegradable resins such as vinyl chloride and polyethylene. Since these are not biodegradable, it is necessary to pull out the seedlings from the pot for transplantation, which not only complicates the operation but also has a problem of planting damage especially at the root portion, and thus improvement has been desired.

Attempts to apply biodegradable materials to the field of agriculture and horticulture have been made in JP-A-51-57533 and JP-A-54-123.
453, JP-A-2-6689, and JP-A-2-286013.
Are disclosed in. Japanese Patent Laid-Open No. 51-57533 discloses
The present invention relates to an implantable flowerpot made of a material obtained by mixing cellulose such as sawdust with a non-biodegradable material such as polyethylene, nylon, or epoxy resin.
Japanese Unexamined Patent Publication No. 54-123453 discloses a method of using a copolymer composed of an aliphatic polyester and an aliphatic polyamide as a material for a planting pot that decomposes and disappears. JP-A-2-6689 uses a composite of cellulose and chitosan. In this case, it is described that the biodegradability can be controlled by the molecular weight and blending amount of chitosan. JP-A-2-286013 discloses a method for forming a composite by forming a film of polyhydroxybutyric acid / polyhydroxyvaleric acid copolymer on the surface of a pot of plant fiber such as paper in order to improve water resistance and strength. Has been done.

[0006] Many review articles on biodegradable polymers suggest the possibility of applying the aliphatic polyester compound to pots for agricultural and horticultural use, but specific examples of the application have been reported. Absent. Gillette's Polym
ers and Ecological Probe
ms (1973) (Plenum Press, Ne
w York) p.74, the results of the pot embedding test of the pot using polycaprolactone are reported.
Destruction of shape has been progressing from about 6 months.

[0005]

The pot for raising seedlings, which is the object of the present invention, is intended for the cultivation of tomatoes, cucumbers, cabbage, Chinese cabbage, lettuce, eggplants, foliage plants, trees, etc.
After obtaining seedlings grown under controlled conditions of around 20 ° C in a vinyl house for 2 weeks to 1 month and transplanting them into the actual field, the container decomposes in about 1 month, and the roots of crops The conditions must be such that the tension is not adversely affected and that unwanted illness is not induced. Thus, there has been a demand for a pot in which the biodegradability of the container is controlled. However, the conventional method has a slow biodegradability (the method of Gillette et al., JP-A-51-57533, JP-A-54-5433). 123453), it is difficult to control the thickness (JP-A-2-6689), or the strength is not sufficient (JP-A-2-286013).
Was not known.

[0006]

[Means for Solving the Problems] For this purpose, the present inventors have examined the use of an aliphatic polyester compound having the best biodegradability or a modified product thereof as the material of the pot. As a result, we found that mainly the inner volume of the pot and the thickness of the pot had a great influence on the growth of seedlings and the crops after transplantation, and by limiting the thickness and shape to a certain range, we could obtain an elaborate seedling raising pot. It came to be able to achieve the purpose.

That is, the present invention provides (1) a film thickness of 50 μm to 200 μm and a diameter of 3 to 10 c
m or a container having a side of 3 to 10 cm and a height of 3 to 15 cm in the form of a cylinder or a prism, the material being a biodegradable aliphatic polyester compound or its modified pot for raising seedlings ( 2) The above-mentioned modified product contains 1 part of an aliphatic polyester compound.
A seedling-growing pot characterized by being a polymer modified with 0% by weight or less of a diisocyanate compound (3) Characterized by containing a fungicide (1) (2)
(4) A pot for raising seedlings according to item (1) to (3), wherein the material (4) for raising seedlings contains activated carbon and / or carbon black.

The seedling raising pot of the present invention will be described in detail below. As the material of the polymer used in the pot for raising seedlings of the present invention, a biodegradable aliphatic polyester compound or a modified product thereof is used. Specifically, poly-3-hydroxybutyric acid, 3-hydroxybutyric acid and 3-hydroxyvaleric acid are used. , A copolymer of 3-hydroxybutyric acid and 4-hydroxybutyric acid, or those produced by microorganisms such as polyesters collectively called poly-3-hydroxyalkanoic acid, polylactic acid, polyglycolic acid, polypropyi Examples thereof include polyhydroxycarboxylic acids produced by a synthetic method such as olactone, polybutyrolactone, and polycaprolactone.

Further, polyesters produced by condensation polymerization of the following aliphatic dibasic acids and aliphatic diols can also be used. That is, as the aliphatic dibasic acid, succinic acid, adipic acid, sebacic acid, decanedicarboxylic acid, etc., and as the aliphatic diol, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1 , 10-decandione and the like can be mentioned.

The above-mentioned aliphatic polyester compound can be modified with preferably 10% by weight or less of a diisocyanate compound to change its biodegradability and mechanical strength. As the diisocyanate compound used for this purpose, 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,12-diisocyanatododecane,
Examples thereof include isophorone diisocyanate and 4,4′-diisocyanatodiphenylmethane.

This reforming is carried out by using a solvent having no active hydrogen such as benzene, toluene, xylene, dichloromethane,
1,2-dichloroethane, chloroform, ethyl acetate,
It can be carried out using ethyl lactate, ethyl lactate, dioxane, tetrahydrofuran, dimethylformamide, dimethylsulfoxide or the like, but may be carried out under heating and melting without a solvent. The reaction temperature is preferably room temperature to about 200 ° C.

The method for producing the seedling raising pot of the present invention will be described. It is possible to cut a film made of the above material into a desired size and use an adhesive, or a method of forming a desired shape by means such as heat melting, or a method such as an injection molding method, There is no particular limitation.

Next, the size and shape will be described. The most important dimension is the thickness. As mentioned above, 2 weeks to 1 month is a period for raising seedlings, at which time the shape is firmly maintained, and after being transplanted to the actual field, it decomposes in about 1 month to maintain the shape. It is necessary to have nothing. To this end, 200 μm or less, preferably 150 μm
It was necessary to have a thickness of m to 20 μm, and when it exceeds 200 μm, it was confirmed that the growth of roots and the number of leaves after transplantation was hindered and growth was inhibited. If it is 20 μm or less, there is a problem in strength and handling. The height of the pot is preferably 3 to 12 cm. The diameter or one side is 3-10c
m It is preferably a cylindrical or rectangular container having a size of 3 to 7 cm, and these are for securing an amount of soil necessary for growth from germination to transplantation, and for growing seedlings before the pot is decomposed. It is a size that is adopted so as not to cause inhibition. The cylindrical shape is most preferable from the viewpoint of handling, disassembly, and production, but it may be prismatic, and they may be slightly deformed, that is, as long as it has a volume of the above-mentioned dimension. .. Also, it is better to make a hole for draining water on the bottom surface, but it is not necessary.

Polymer by James Gillette
s and EcologicalProblems
(1973) (Plenum Press), page 73, reports the results of a soil embedding test of a container using polycaprolactone, but the shape finally collapsed after 6 months, and it was used as a pot for raising seedlings. It seems impossible to do. However, the present inventors have found that polycaprolactone can also be sufficiently used with a limited thickness and size.

Plants that can be used in the seedling raising pot of the present invention include tomato, cucumber, eggplant, cabbage, Chinese cabbage,
Lettuce, green onion, broad beans, pak choi, parsley, etc. 2 weeks to 1 month in a greenhouse such as a greenhouse
Under controlled conditions of around 0 ° C to 30 ° C, horticultural crops such as vegetables for which seedlings need to be obtained, and anemones, calendula, which require transplantation within 1 to 2 months after sowing, regardless of crops. Flowers such as Nemophila, Kyoukyo, Rhodanse, Calceolaria, Papaver, Vorticella, Cornflower, etc., such as tree-growing beconia, riegers beconia, kalanchoe, impatiens, poinsettia, etc., can be mentioned as seedlings directly planted. ..
By using the above-mentioned crops and flowers, sufficient strength can be maintained until transplantation even in the market of seedlings and flowers.

It is necessary that seedlings growing in seedling pots and after transplantation do not induce unwanted disease. Normal,
Tomatoes, which are prone to disease, need to be sprayed with a fungicide when the disease occurs, which takes time and effort. The seedling-growing pot of the present invention, by containing a fungicide, the fungicide, along with the decomposition of the seedling-growing pot, shows a sustained-release bactericidal effect that is released in small amounts, preventing the occurrence of mold, and preventing the disease of seedlings. In addition, it is possible to save time and labor on the work, and to give good results on the work hygiene.

The types of fungicides that can be contained in the seedling raising pot of the present invention include thiabendazole, daconyl,
Antifungal agents such as lidomyl and copper compounds are suitable, but small particles and powders are preferable because they must be added to the polymer. Also, even if it is other than that,
If it is soluble in the polymer or solvent, it can be added. The amount of fungicide added is 1% based on the polymer
It is a degree. It is necessary that the bactericide added to the polymer has a sufficient bactericidal effect and does not cause chemical damage. To that end, the fungicide is 1 relative to the weight of the polymer.
% Or less, preferably 0.1% to 0.5%. It is also possible to add an insecticide, a plant-regulating agent, etc. in addition to the bactericidal agent in the material from which the pot of the present invention is made.

Activated carbon and / or carbon black can be added to the seedling-growing pot of the present invention for the purpose of shading in order to protect roots from light. In addition to this, a biodegradable colorant or the like can be added. As the coloring agent to be added, black is desirable in order to expect a stain and a high light-shielding effect on the seedling raising pot until transplantation, but if it is biodegradable,
There is no particular limitation. Activated carbon added to the polymer and /
Alternatively, carbon black is required to exhibit a sufficient light-shielding effect within a range that does not reduce the strength of the added polymer. For that purpose, the total amount of activated carbon and / or carbon black is 10% or less, preferably 0.5 to 8.0%, based on the weight of the polymer.

[0019]

EXAMPLES The present invention will be described more specifically by way of examples.

Examples 1 to 10 Poly 3-hydroxybutyric acid / poly 3 derived from microbial fermentation synthesis
-Hydroxyvaleric acid copolymer (hereinafter Poly (3HB
-3HV)), a film of each polymer of chemically modified polycaprolactone and polybutylene adipate hexamethylene diisocyanate (hereinafter abbreviated as PBA (modified product)) is a cylindrical type having a bottom diameter of 5 cm and a height of 6 cm. Processed into a nursery pot. Soil: 3 which had been sterilized with chloropicrin in advance, and mullet: 1 were mixed at a ratio of 1: 3, and a fertilizer corresponding to 0.9% of the sterilized soil was added.
The fertilizer is Chissophosca (N: P: K = 13: 12: 1).
0) was used. This soil was filled in a nursery pot, and 3 seeds were sown in each pot. The results obtained when tomato is selected as an example are shown below. The variety used was Mizuhide tomato (production area: Gunma prefecture), and the seeding depth was 1.5 cm. Two weeks after sowing, thinning was performed so that one pot was prepared for each pot. The germination rate was 100%. Three weeks after sowing, the seedling raising pot was transplanted into the soil so that the pot was completely buried in the soil.

At this time, there was no large difference in growth between the seedling raising pots of the respective examples. In addition, each seedling raising pot maintained its strength and shape sufficiently, and the work efficiency at the time of transplantation was very good. Ordinary seedlings may stop growing 3 days to 1 week after transplantation due to planting damage or the like, but the seedlings transplanted together with the seedling-growing pot also had good growth after transplantation. Also, after transplantation,
The seedlings grew well, no disease or chemical damage occurred during the experiment, but mold was found in the pots containing no fungicide.

After 4 weeks from transplantation, the decomposition state of each pot,
A final survey was conducted on the growth of seedlings. All this testing was done in the greenhouse. The results are shown on the next page. In addition,
Five pots were used for each test section of the seedling raising pot, and the average value of each pot was used as the result. In addition, seedlings were grown in ordinary vinyl chloride pots, removed at the time of transplantation, and transplanted as a control.

Type of polymer Film thickness Type of bactericide Addition amount (μm) (%) Example 1 Poly (3HB-3HV) 50 None 2 Poly (3HB-3HV) 50 Daconyl 0.23 Poly (3HB-3HV) 50 thiabendazole 0.2 4 Poly (3HB-3HV) 100 none 5 polycaprolactone 50 none 6 polycaprolactone 50 daconyl 0.2 7 polycaprolactone 50 thiabendazole 0.2 8 PBA (modified product) 50 none 9 PBA (modified product) 50 Daconyl 0.2 10 PBA (modified product) 50 Thiabendazole 0.2 Comparative Example 1 Poly (3HB-3HV) 200 None

Growing state (compared with "control example"): No adverse effect on growth is observed. +: A slight adverse effect on growth is recognized. ++: Adverse effects on growth are clearly observed. Root amount 3.0: Root amount is large. 2.0: The amount of roots is slightly small. 1.0: The amount of roots is very small. Decomposition index of polymer (at the time of 4 months) 5.0: Completely decomposed. 4.0: Almost disassembled and the outer shape is not retained. 3.0: Disassembly is progressing well, but the outer shape is recognized. 2.0: Decomposition is in progress, but the outline remains clearly. 1.0: Almost no decomposition or only the vicinity of the bottom surface is decomposed.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

Those using a biodegradable pot without addition of a bactericide have a slightly inferior growth before transplantation. It is considered that this is because molds were found only in the pots in this area, which adversely affected the growth of seedlings. The seedlings in the pot without the addition of the bactericide almost caught up with the growth of the control seedlings one week after the transplantation. This is because the control example at the time of transplantation had a slightly slower growth due to root planting damage, whereas the one using the biodegradable nursery pot grew satisfactorily because there was no planting damage. It is thought that the difference between
Comparative Example 1 with a film thickness of 200 μm and no bactericide added had poor degradability from the time of transplantation to the final investigation, and at any time
The growth was inferior. In the pot containing the fungicide, the progress of decomposition was no different from that in the group containing no fungicide, and the addition of the fungicide suppressed the generation of mold and gave good results for the growth of seedlings.

Example 11 The same pot as that used in Example 3 was used for chrysanthemum inoculation and transplanted 1 month later. The strength up to transplantation was sufficient, and the work efficiency during transplantation was improved. After transplanting, the seedlings grew smoothly and no disease or drug damage occurred.

Example 12 The same pot used in Example 6 was seeded with periwinkle seeds. After one month, excellent seedlings were obtained and transplanted.
The strength up to transplantation was sufficient, and the work efficiency during transplantation was good. There was no mold, and the seedlings grew well and flowered even after transplantation. No disease or drug damage occurred.

Examples 13 and 14 Polymer type Film thickness Additive amount (μm) (%) Example 13 Poly (3HB-3HV) 70 Activated carbon 5.0 Example 14 Polycaprolactone 70 Carbon black 5.0 Example Pots were prepared in the same manner as in 1 to 10, and seeds of morning glory were sown in the prepared soil. A month later, excellent seedlings were obtained and transplanted. The strength up to transplantation was sufficient, and the work efficiency during transplantation was good. Mold generation was few, and the seedlings grew well and flowered even after transplantation. No disease or drug damage occurred.

[0032]

EFFECTS OF THE INVENTION The seedling raising pot of the present invention maintains sufficient strength from seeding to post-growth transplantation of seedlings, and its biodegradability is finely controlled after transplantation, which does not adversely affect rooting. By using this, excellent seedlings can be obtained, and the seedlings grow well even after transplantation. The work efficiency at the time of transplantation is improved, and the problems of work complexity and seedling damage are improved. In addition, disease can be suppressed by incorporating a germicide into the material of the pot.

Claims (4)

[Claims] 1. A film thickness of 50 to 200 μm and a diameter of 3 to
10 cm or 3 to 10 cm on a side and 3 to 15 c in height
Pots for raising seedlings, which are cylindrical or prismatic in the range of m, and whose material is a biodegradable aliphatic polyester compound or its modified product 2. A pot for raising seedlings, wherein the modified product according to claim 1 is a polymer obtained by modifying an aliphatic polyester compound with 10% by weight or less of a diisocyanate compound. 3. The seedling raising pot according to claim 1, wherein the material contains a bactericide. 4. The pot for raising seedlings according to claim 1, wherein the material contains activated carbon and / or carbon black.