JPH11332391A - Seedling raising pot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seedling raising pot which can be buried together with the seedlings when seedlings are transplanted without taking out them, is easily degradable in the soil where the seedlings are transplanted, does not disturb the growth of the plant in this case, and does not need the filling of soil into it on the planting of the seedlings or the sowing of seeds. SOLUTION: This pot is formed by being molded from a polyurethane raw material and comprises a seedling culturing medium part 11 consisting of a foamed body and a skin layer 21 integrally formed on its surface. The seedling culturing medium part 11 has an air permeability of 50-200 cm<3> /cm<2> /sec, a 25% compressive strength of 0.05-0.5 kg/cm<2> and a flyability of 50% or more. The skin layer has a tensile strength of 0.1-1.0 kg/cm<2> , a flyability of 50% or more and a thickness of 50-500 μm, and the skin layer has been removed at the surface of the part where seeds are sowed or seedlings are planted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seedling raising pot, and more particularly, to a seedling growing pot made of a porous resin, the seedling raising pot can be transplanted into soil, and can be easily crushed when the ground is subsequently plowed. Seedling pot to be used.

[0002]

2. Description of the Related Art Conventionally, plant seedlings such as flowers and vegetables have been sold with their roots wrapped in paper or the like and bound with straw or the like. In recent years, the soil as a seedling culture medium has been packed in a flexible pot-like container (usually referred to as a seedling raising pot) made of polyethylene or the like in consideration of workability of a plant producer and ease of handling at the time of sale. Seedlings are now sold with seedlings planted, and the roots are almost never wrapped in paper or the like. For small seedlings that have just germinated, use a container made of polyethylene sheet with a large number of recesses formed adjacent to each other, so that they are cultivated and stored in a state where they are planted in soil filled in the recesses. became. In addition,
At the time of sale, the seedlings are cut and separated appropriately between the concave portions to obtain a required number of seedlings. When transplanting the seedlings into a garden, a planter, or the like, the seedlings are taken out of the container together with the soil and planted.

[0003] However, the remaining containers after transplanting the seedlings are:
To use as a substitute for a pot for unglazed or the like, the rigidity is weak, the size is too small, and the aesthetic appearance is poor. Therefore, it is usually discarded, and there has been a problem that it is not suitable for recent waste reduction and environmental protection. In addition, the collection route for collecting and reusing is not provided, and the problem of disposal cannot be easily solved.

[0004] In order to solve the above-mentioned problem, a container is formed of a biodegradable plastic, and a seedling is not taken out of the container at the time of transplanting, but is buried in the soil at the transplant site, and the container is decomposed by microorganisms in the soil. It is possible. But,
Decomposition conditions in the soil are severe, and the decomposition rate of the container is slow due to a small amount of oxygen. Therefore, it takes a long time to completely decompose and convert to soil, and there is a problem that the resin is usually easily left as a film-like resin. The film-like resin remaining in the soil in this manner may inhibit the growth of seedlings. Further, in farmers and the like, when the time of harvesting and flowers of vegetables has passed, and when cultivating the soil with a cultivator to plant another plant again, the film-shaped resin remaining in the soil is removed by a machine such as a cultivator. Troubles such as entanglement or clogging of the machine occur.

[0005] In addition, since the conventional container has to be filled with soil when planting seedlings, the operation is troublesome for plant producers who temporarily plant many seedlings, and securing a large amount of soil is also a problem. Becomes

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above points, and it is possible to plant a seedling-raising pot without transplanting the seedlings without removing the seedlings. The present invention provides a seedling raising pot which does not obstruct the growth of the seedlings and does not need to be filled with soil when planting seedlings or sowing seeds in the pots.

[0007]

The present invention, which achieves the above object, relates to a seedling raising pot characterized by molding a porous resin capable of raising seedlings. This makes it possible to grow seedlings without using soil. The seedling-capable porous resin refers to a continuous foamed resin, specifically, a phenolic resin, a urea resin, a cellulose foam,
Examples include polyvinyl alcohol resin (PVA), vinyl fluoride resin (PVF), urethane foam, and the like.

Further, it is preferable that the seedling raising pot has a seedling culture medium portion made of a foam and a skin layer integrally formed on the surface thereof. By forming the skin layer integrally with the surface of the seedling culture medium, the seedling culture medium that is brittle during handling and becomes easy to fall off from the surface as a powder is not exposed, and the handling and workability of the seedling pot are improved. .

[0009] The seedling culture medium has an air permeability of 50 to 200.
cm ³ / cm ² / sec, 25% compressive strength is 0.05-0.
It is preferable that the weight is 5 kg / cm ² and the flyability is 50% or more. The air permeability of the seedling culture medium affects water retention and water absorption, and the air permeability is 50 to 200 cm ³ / cm.
^{When the} rate is less than ² / sec, water does not quickly penetrate into the seedling culture medium part, and after permeation, drainage is poor and root rot of the seedlings is liable to be caused. On the contrary, the air permeability is higher than 200 cm ³ / cm ² / sec. If there is, the water holding is poor and water is easily drained. If the flyability is 50% or more, the soil can be crushed when plowed.

The skin layer has a flyability of 50.
% Or more, and the thickness is preferably 50 to 500 μm. If the flyability of the skin layer is 50% or more, it can be crushed when the soil is plowed. Further, when the thickness of the skin layer is less than 50 μm, the seedling pot is easily damaged when handling the seedling pot because the skin layer is thin, and care must be taken in handling. On the other hand, if the thickness of the skin layer is larger than 500 μm, the seedling pot is decomposed by the soil, but the decomposition takes a long time, so that the pot is easily left in the soil. In addition, it also hinders the seedlings planted in the seedling raising pot from taking root.

It is preferable that the porous resin capable of raising seedlings comprises a rigid polyurethane foam. The thickness of the skin layer can be easily controlled by forming the rigid polyurethane foam, changing the amount of the foaming agent added during molding, or controlling the temperature of the foaming mold. it can. In addition, the rigid polyurethane foam does not contain a highly toxic low molecular weight compound, and is also excellent in preventing environmental pollution.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of a seedling raising pot according to one embodiment of the present invention, FIG. 2 is a 2-2 cross-sectional view thereof, FIG. 3 is a cross-sectional view of the seedling raising pot of FIG. 1 at the time of molding, and FIG. FIG. 5 is a perspective view showing a seedling raising pot of another embodiment, FIG. 6 is a 6-6 enlarged sectional view, and FIG. 7 is a cross-sectional view showing the seedling raising pot of FIG. 5 at the time of molding. It is.

The seedling pot 10 of the present invention shown in FIG. 1 and FIG. 2 which is an enlarged partial cross-sectional view of FIG. 2 is a rigid polyurethane molded from a foamed polyurethane material and having communication, water absorption and water retention suitable for seedling raising. The pot 10 has a top surface 10 a in the form of a short column having a diameter larger than that of the bottom surface 10 b, and is composed of a seedling culture medium portion 11 and a skin layer 21. This seedling raising pot 10 is buried in soil such as a garden or a planter as it is when a seedling is transplanted. Then, when the transplanted plant finishes flowering or harvesting, and when planting another thing in the soil again, when cultivating the soil with a scoop or the like, the seedling raising pot 10 hits the scoop or the like and is easily crushed. Things.

The seedling culture medium section 11 is made of a foam at a portion where a seedling is planted or a seed is sown in place of conventional soil. The foam constituting the seedling culture medium part 11 has an air permeability (measured by JIS L1096 A method) so that the seedlings of the plant can grow well and the soil can be easily crushed when cultivating the soil. Is 50 to 200 cm ³ / cm ² / sec, 25
% Compressive strength (measured according to JIS K 7220) is 0.
05-0.5 kg / cm ² , flyability (AST
(Measured by MC421-61) is preferably 50% or more, particularly preferably 50 to 97%.
If the 25% compressive strength is lower than the above range, it is too brittle to plant seedlings and maintain roots. On the other hand, if the compressive strength is too high, not only rooting and seedling growth during seedling raising is inferior, but also scoops in soil, etc. Grinding becomes difficult. Also, when the flyability is lower than the above range, it is difficult to grind with a scoop or the like. A cell having a cell number in this range is a range in which both air permeability and water retention are preferable for plants.

The skin layer 21 functions as a container for protecting the seedling culture medium 11 and is formed integrally with the surface of the seedling culture medium 11. When the seedling pot 10 was molded from a polyurethane raw material, the skin layer 21 was formed as a dense layer by contacting the foam with the mold surface of the foaming mold and crushing bubbles by the foaming pressure. Things. The skin layer 21 has a flyability of 50% or more in order to prevent breakage during handling of the seedling pot and ensure easiness of crushing with a scoop or the like in the soil.
In particular, those having a thickness of 50 to 97% and a thickness of 50 to 500 μ are preferred. Further, the tensile strength (JIS K6251)
Dumbbell shape (measured by No. 3 type) is 0.1 to 1.0k
g / cm ² is preferable in that it can prevent breakage during handling of the seedling raising pot and more easily crush with a scoop or the like in the soil.

In the seedling raising pot 10, the skin layer is integrally formed so as to cover the entire circumference of the seedling raising part 11 by molding. Or on the side of planting seedlings,
The skin layer is removed with a knife or the like, so that sowing and seedling planting are facilitated. Of course, instead of removing the skin layer on the entire upper surface 10a for sowing seeds or planting seedlings, a hole may be made in a part of the skin layer covering the upper surface 10a to enable sowing or seedling. In addition, holes or cuts (not shown) for draining water may be appropriately formed on the bottom surface of the skin layer 21 using a knife or the like.
Then, drainage when a large amount of water is given to the seedling raising pot 10 at once due to heavy rain or the like is performed more smoothly.

Next, a production example of the seedling raising pot 10 will be described. The production of the seedling raising pot 10 is performed by a known molding using a foaming mold 30 as shown in FIG. The foaming mold 30 includes a lower mold 31 and an upper mold 3.
3, a molding cavity 34 having a shape substantially equal to the outer shape of the seedling raising pot 10 is formed therein. The molding cavity 34 is filled with a predetermined amount of the polyurethane raw material P and foamed, and the molded product formed into the molding cavity shape is then demolded.
As can be understood from FIG. 4 showing a part of this molded product in an enlarged manner, the obtained molded product 10A has a skin layer 21 formed on the entire surface of the seedling culture medium portion 11 made of a foam.
Therefore, as for the skin layer 21a on the upper surface of the molded article 10A which is a surface for sowing a seed or a surface for planting a seedling, the blade 35
Etc. Thus, the seedling raising pot 10 including the seedling growing medium portion 11 and the skin layer 21 remaining on the side and bottom surfaces thereof is obtained.

As the polyurethane raw material, a polyurethane raw material containing a polyol component, a polyisocyanate and an inorganic filler is used. The polyol component includes a polyol, a foaming agent, a catalyst, and a foam stabilizer. In this case, the polyol contains the polyols A, B, C, and D described below, and the total amount of the polyol is 100%.
30 parts by weight of polyol A, 5 to 25 parts by weight of polyol B, and 5 to 25 parts by weight of polyol C.
１５15 parts by weight and polyol D in the range of 20-40 parts by weight.

The polyol A has a hydroxyl value of 140 to 190.
(A polyoxyalkylene portion is composed of 90 to 100 mol% of oxypropylene groups and 0 to 10 mol% of oxyethylene groups). Polyol B has an oxyethylene group content of 70 to
90 mol%, a polyoxyalkylene triol having a hydroxyl value of 28 to 42. Polyol C is an oxyalkylated product of ethylenediamine (oxyalkylated portion contains 0 to 25 mol% of oxyethylene groups) and has a hydroxyl value of 600 to 850. Polyol D
Is a polyoxyalkylene glycol monoalkyl ether having an oxyethylene group content of 70 to 100 mol% and a hydroxyl value of 56 to 187.

Examples of the polyisocyanate include those commonly used for rigid polyurethane foams such as crude or polymeric diphenylmethane diisocyanate (MDI), crude tolylene diisocyanate (TDI), prepolymers thereof, and mixtures of crude MDI and crude TDI. What is used for is used. The ratio between the polyisocyanate and the polyol is such that the isocyanate index is in the range from 35 to 75, in particular from 40 to 60.

The inorganic filler is added mainly for the purpose of making the seedling culture medium 11 and the skin layer 21 preferably brittle, and powders such as calcium carbonate, clay, aluminum hydroxide and barium sulfate are used. Used. The particle size of the powder is preferably 500 to 2000 mesh. Further, the amount of the inorganic filler is preferably 15 to 55 parts by weight, particularly preferably 20 to 50 parts by weight based on 100 parts by weight of the total amount of the polyol.

As the blowing agent, water is usually used. The amount of water is
The amount is 5 to 15 parts by weight, especially 8 to 12 parts by weight based on 100 parts by weight of the total amount of the polyol. An appropriate amount of a catalyst for rigid polyurethane foam such as an amine derivative or a morpholine derivative is used. As the foam stabilizer, those for rigid polyurethane foams are generally used. In addition, a compounding agent that promotes biodegradability or hydrolyzability can also be added.

FIG. 5 is a perspective view of a seedling raising pot 40 according to another embodiment, and FIG. 6 is a 6-6 enlarged sectional view thereof. The seedling-growing pot 40 is substantially plate-shaped, and has a seedling-growing medium portion 41 formed of a plurality of foams partitioned in a lattice shape, and a skin layer 51 integrally formed on the side and bottom surfaces of the seedling-growing medium portion 41. The skin layer is cut off on the upper surface of the pot for sowing seeds and planting seedlings. The physical properties of the foam and the skin layer are the same as those shown in FIGS. 1 and 2. . Further, the seedling growing pot 40 is separated and cut between the appropriate seedling growing medium portions 41 when selling the seedlings. The seedling raising pot 40 is manufactured by injecting the polyurethane raw material P into a molding cavity 64 of a foaming mold 60 comprising a lower mold 61 and an upper mold 63 shown in FIG. This is performed by removing the skin layer on the upper surface. In addition, instead of removing the skin layer on the entire upper surface of the surface on which the seeds or seedlings are planted, that is, the upper surface of the pot, a hole of an appropriate size may be formed in a part of the upper surface.

Example 1 A molding cavity having an upper end diameter of 80 mm, a lower end diameter of 50 mm, and a height of 70 mm was set at 40 ° C., and the molding cavity was filled with 8 g of a polyurethane raw material described later, as shown in FIG. Molded 30 seedling-growing pots, measured the physical properties of the seedling-growing medium and the skin layer for 10 of them, and temporarily planted pansy and parsley for the other 10 for 10 days, and then cultivated the seedlings. Each pot was transplanted to the ground and cultivated for 20 days.
The remaining 10 seedling pots were buried in the ground without planting anything. Thereafter, the ground in which the seedling pots were buried was plowed with a scoop, and the crushed state of the seedling pots was visually checked. The results are as shown in Tables 1 and 2.

(Blending of used polyurethane raw materials) Polyol A: polyoxypropylene triol, hydroxylated; 158, oxyethylene group content; 0 mol%,
Polyol B: polyoxyalkylene triol, hydroxylated: 33.7, oxyethylene group content: 80 mol%, blended amount: 15 parts by weight Polyol C: oxypropylated product of ethylenediamine, Hydroxyl value; 760, oxyethylene group content;
0 mol%, blending amount: 12 parts by weight Polyol D: polyethylene glycol monomethyl ether, hydroxyl value: 100, oxyethylene group: 100
Mol%, compounding amount: 28 parts by weight Polyisocyanate: Crude MDI (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Millionate MR-40")
0 "), isocyanate content; 30%, isocyanate index; 50-inorganic filler: calcium bicarbonate (trade name" KS-1300 ", manufactured by Dowa Calfine Co., Ltd.), blending amount: 35
Parts by weight-Blowing agent: water, blending amount: 9 parts by weight-Catalyst: 2- (2-dimethylaminoethoxy) ethanol which is an amine derivative, blending amount: 1 part by weight-Foam stabilizer: used in production of flexible polyurethane foam Dimethylpolysiloxane-polyether block copolymer having a pendant structure and 50 mol% of oxypropylene groups and oxyethylene groups, and dimethylpolysiloxane in the block copolymer. Content of siloxane portion: 10% by weight, blending amount: 5 parts by weight, and a methoxy group is bonded to the terminal of the polyether portion. -Bubble communicating agent: dimethylpolysiloxane (trade name "L-45", manufactured by Nippon Unicar Co., Ltd.), viscosity: 1000
cps, compounding amount: 0.7 parts by weight

(Example 2) A seedling pot was produced under the same conditions as in Example 1 except that the content of the dimethylpolysiloxane part in the block copolymer in the foaming agent of Example 1 was changed to 20% by weight. Physical properties and growth were examined. The results are as shown in Tables 1 and 2.

(Example 3) The isocyanate index in Example 1 was set to 40, and the content of the dimethylpolysiloxane part in the block copolymer in the foaming agent was set to 15
A seedling-growing pot was produced under the same conditions as in Example 1 except that the weight% and the content of the inorganic filler were changed to 20 parts by weight, and physical properties and growth were examined. The results are as shown in Tables 1 and 2.

A seedling-growing pot of a comparative example having the same composition as that of the example was prepared in the following manner, and its physical properties, growth and the like were examined. The results are as shown in Tables 1 and 2.

(Comparative Example 1) The isocyanate index in Example 1 was set to 80, and the content of the dimethylpolysiloxane part in the block copolymer in the foam stabilizer was 15
A seedling-growing pot was produced under the same conditions as in Example 1 except that the amount was changed to% by weight.

Comparative Example 2 A seedling-growing pot was produced under the same conditions as in Example 1 except that polyol D was not used.

Comparative Example 3 A seedling pot was produced under the same conditions as in Example 1 except that the polyol C was not used.

Comparative Example 4 A seedling growing pot was produced under the same conditions as in Example 1 except that the content of the inorganic filler in Example 1 was changed to 100 parts by weight.

Comparative Example 5 A seedling-growing pot was produced under the same conditions as in Example 1 except that the molding cavity was filled with 7.2 g of a polyurethane raw material.

Comparative Example 6 A seedling pot was produced under the same conditions as in Example 1 except that the isocyanate index in Example 1 was changed to 30.

Comparative Example 7 A seedling-growing pot was produced under the same conditions as in Example 1 except that the temperature of the molding cavity was changed to 600.degree.

Comparative Example 8 A nursery pot was prepared under the same conditions as in Example 1 except that the molding cavity was filled with 8.8 g of a polyurethane raw material.

[0037]

[Table 1]

[0038]

[Table 2]

As shown in Tables 1 and 2, in the embodiment of the present invention, the seedlings are not only planted in the seedling pots but also when they are transplanted to the ground or the like. Grew well. When the ground on which the seedling pots were planted was plowed with a scoop, the seedling pots could be easily crushed. On the other hand, in the comparative example, the growth of the seedlings after provisional planting or transplantation was poor, the seedling pots could not be crushed when cultivating the ground where the seedling pots were planted, or the seedling pots were too brittle to Problems such as breakage easily occurred during handling.

[0040]

As described above, according to the seedling-growing pot of the present invention, the seedlings grown in the seedling-growing pot are placed on the ground, etc. Transplanting does not impair seedling growth. Therefore, not only the work at the time of transplantation can be easily performed, but also the seedling raising pot is not generated as waste. Furthermore, since the seedling pot of the present invention planted on the ground is easily crushed by a scoop or a cultivator when the ground is subsequently plowed, there is no problem of being entangled in the plowing machine, and the plant to be planted thereafter It does not disturb the root growth. In addition, the seedling raising pot of the present invention does not require soil and is light in weight and easy to handle.

[Brief description of the drawings]

FIG. 1 is a perspective view of a seedling raising pot according to one embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a cross-sectional view showing the seedling raising pot of FIG. 1 during molding.

FIG. 4 is a partially enlarged cross-sectional view showing skin layer resection after removal from the mold.

FIG. 5 is a perspective view showing a seedling raising pot of another embodiment.

FIG. 6 is an enlarged sectional view taken along line 6-6 in FIG. 5;

FIG. 7 is a cross-sectional view showing the seedling raising pot of FIG. 5 during molding.

[Explanation of symbols]

 10,40 Seedling pot 11,41 Seedling culture medium part 21,51 Skin layer

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[Procedure amendment]

[Submission date] June 12, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0035

[Correction method] Change

[Correction contents]

(Comparative Example 7) A seedling-growing pot was produced under the same conditions as in Example 1 except that the temperature of the molding cavity was changed to 60 ° C.

Claims (5)

[Claims] 1. A seedling pot formed by molding a porous resin capable of raising seedlings. 2. The seedling raising pot according to claim 1, comprising a seedling culture medium portion made of a foam and a skin layer integrally formed on the surface thereof. 3. The air permeability of the seedling culture medium is 50 to 200 cm.
³ / cm ² / sec, 25% compressive strength 0.05-0.5k
3. The seedling raising pot according to claim 2, wherein the potability is g / cm ² and the flyability is 50% or more. 4. The seedling raising pot according to claim 2, wherein the skin layer has a flyability of 50% or more and a thickness of 50 to 500 μm. 5. The seedling raising pot according to claim 1, wherein the porous resin capable of raising seedlings is a rigid polyurethane foam.