JPS61234723A - Mineral fiber mat for culturing plant - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention A. Field of Industrial Application The present invention relates to a mineral fiber mat useful as an artificial culture medium for plants, especially vegetables. The present invention provides a mineral fiber mat for plant cultivation that can retain water and air in a well-balanced manner by containing water-repellent mineral fiber granular cotton dispersed therein.

BACKGROUND OF THE INVENTION Mineral fiber mats are excellent in water retention, air permeability, shape retention, etc., and are corrosion resistant, so they are preferably put to practical use as artificial culture media for long-term cultivation of plants.

Mineral fiber mats are made by melting mineral and inorganic raw materials such as rocks and slag and blowing them away using centrifugal force and fumes to create fibers.
It is produced by stacking and collecting cotton on a net conveyor with a spray adhesive (mainly thermosetting resin adhesives such as phenol resin are used), and then heat-treating the adhesive to dry and harden it. The fibers constituting the mat are oriented in a direction parallel to the mat surface, and the LLI fibers are partially adhered to each other to maintain their shape. This mineral fiber mat is 30~200
It is produced with a density of kg/-.

By the way, this mineral! If the I-fiber mat is used as an artificial medium as it is, since the mineral fibers are hydrophobic, water permeability is low and it is difficult to absorb water uniformly.The mat tends to absorb water insufficiently or unevenly, making it difficult to sow and raise seedlings. When used as a bed, undesirable results such as uneven germination and inhibition of root growth occur, which also has negative effects on long-term cultivation.

In order to solve this drawback, a hydrophilic agent such as an anionic or nonionic surfactant is added by spraying during the production of the mineral fiber mat to impart water absorption properties.

C1 Problems to be Solved by the Invention When a conventional water-absorbing mineral fiber mat to which a hydrophilic agent is uniformly adhered is used as a culture medium, water easily penetrates into the mat. The moisture content tends to be too high and the air content to be too low at the bottom of the mat.
There was a problem that root rot was likely to occur during long-term cultivation.

Therefore, it has been proposed to use blended wool, which is a blend of mineral fiber wool that has been treated to make it hydrophilic and mineral fiber wool that has been treated with a water repellent agent, as an artificial medium. Because the constituent fibers of wool are not bonded together, they have almost no mechanical strength or shape retention, making them difficult to handle, and they are compressed by the weight of the above-ground parts during the cultivation period, making it impossible to retain the desired amount of air. It has hardly been put into practical use.

20 Means for Solving Problems The present invention adopts the following means in order to solve the above-mentioned conventional problems.

That is, when manufacturing a water-absorbing mineral fiber mat using a normal manufacturing method, granular mineral fiber cotton treated with a water repellent is incorporated into the mat, and the adhesive is dried and hardened. As shown in the cross-sectional view shown in FIG. 1, this is a mat for an artificial culture medium in which water-repellent mineral fiber granular cotton 2 is dispersed and contained within a main water-absorbing mineral fiber mat 1.

Mineral fibers in the present invention include rock wool, glass wool, glass wool, and the like.

Anionic surfactants or nonionic surfactants are mainly used as hydrophilic agents to obtain water-absorbing mats.

Examples of anionic surfactants include fatty acid salts, alkyl sulfate ester salts, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl sulfosuccinates, alkyl phosphate ester salts, and polyoxyethylene alkyl sulfate ester salts.

Naphthalenesulfonic acid condensates, lignosulfonates, and the like are preferred.

Suitable nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, glycerin fatty acid ester, and block polymers of oxyethylene oxypropylene.

These anionic and nonionic surfactants may be used alone or in combination, or anionic and nonionic surfactants may be used in combination.

Although various adhesives can be used as the adhesive for bonding the mineral fibers, thermosetting resin adhesives such as phenol resin and urea resin are suitable.

Water-repellent mineral fiber granular cotton is made by adding a small amount of water repellent (mineral oil, wax, oil, fat, metal soap, fatty acid, silicone resin, etc.) to an adhesive solution when manufacturing a regular mineral fiber mat. A mat in which fibers are bonded together and a water repellent film is formed on the fiber surface is mechanically defibrated into agglomerates with a diameter of about 5 to 20 mm, which is advantageously used industrially, but of course other methods can also be used. Mineral fibers may be made into granular cotton and treated with a water repellent by a method.

Next, an example of the method for manufacturing the mineral fiber mat for culturing plants of the present invention will be described.

Raw materials such as rocks and slag are melted in a cubera, and the molten metal is made to flow down onto the high-speed rotating surface of the spinner wheel, and is blown into fibers by blowing high-speed airflow from the side. At the same time, a hydrophilic agent is mixed in from the center of rotation of the spinner wheel. The added adhesive is sprayed and adhered to the fiber surface in an air stream and falls onto the net conveyor surface. By jetting and mixing mineral fiber granular cotton treated with a water repellent into the fiber falling path, a stacked laminated mat in which hydrophilic fibers and water repellent granular cotton are uniformly mixed is formed on the net conveyor, and this is heat-treated. By drying, the mineral fiber mat of the present invention is obtained.

This mineral fiber mat usually has a porosity of 95% or more, with a porosity of 50 to 50%.
It has a density of 120k (1/-) and a thickness of 50 to 150 mm+, and is cut into appropriate dimensions to make an artificial medium.

Although the above-mentioned water-repellent mineral fiber granular cotton has a porosity of 95% or more, the adhesion between the fibers itself is incomplete or there is no bonding at all, and the mechanical strength is extremely weak. If more than 5% by weight is mixed in, the shape retention of the mat will decrease and the tendency of the mat to compress and deform during cultivation will increase, which is undesirable, and if it is mixed in at 5% by weight without swirling, a sufficient effect cannot be obtained.

Therefore, the mixing rate of water-repellent granular cotton in the mat is 5 to 30% by weight, preferably 10 to 25% by weight.

E6 Effect As mentioned above, the mineral fiber mat for plant cultivation of the present invention has a main water-absorbing mineral fiber mat whose constituent fibers are bonded to each other and has shape retention properties, and has water-repellent mineral fiber granular cotton inside. Since it is dispersed and retained, water and nutrient solution that flows down from the top surface of the mat or is supplied by suction from the bottom surface of the mat easily penetrates into the water-absorbing mat portion, but does not penetrate into the inside of the water-repellent granular cotton. air is always retained in the core.

Normally, an air content of 5 to 30% by weight is desirable for culture medium for cucumbers, tomatoes, etc., and with conventional mineral fiber mats, the amount of watering had to be constantly controlled.
According to the present invention, even if excessive watering is performed, it is possible to maintain an appropriate air content range, and the air content does not fall below a predetermined level, especially in the lower layer of the mat, which conventionally was prone to excess moisture. Therefore, the root rot that conventionally occurs can be completely prevented.

In the mineral fiber mat of the present invention, the constituent fibers of the main mat are oriented parallel to the mat surface, so if it is flattened and used as a culture medium, the mat will be compressed in the case of plants with a large weight on the growing ground. In such cases, the mineral fiber mat may be bent and folded into a continuous wave shape, or the mat may be cut so that the cut surfaces are vertical. Therefore, it is desirable to provide compression resistance by orienting the fibers in the vertical direction.

EXAMPLE When producing a rock wool mat using a conventional multi-rotor type fiber manufacturing equipment, an aqueous solution containing a phenol resin and 5% by weight of sodium alkylbenzenesulfonate based on the phenol resin was added to the phenol resin and rock wool. Separately prepared water-repellent rock wool granular cotton with a particle size of 5 to 20 mm is sprayed to a concentration of 2% by weight during the fiberization blowing process, and placed in the flow path until the fibers fall onto the net conveyor. The phenol resin was dispersed and blown into the product mat at a ratio of 10% by weight, and the mixture was deposited on a net conveyor in a uniformly mixed state f1 layer, and the phenol resin was cured by hot air treatment to obtain the product of the present invention.

The above-mentioned water-repellent Rock Cool granular cotton is produced by adding Marlex 69 ( A treatment solution added with Oil Emulsion (trade name, manufactured by Nippon Oil Co., Ltd.) is sprayed on rock wool so that the phenol resin is 2% by weight to form a heat-cured rock wool mat, and the mat is finely divided using a defibrator. It is obtained by granulating it into a roughly spherical shape, and most of the bonds between its constituent m-spaces are destroyed during the decomposition and granulation process, and its shape retention is extremely low, but its porosity is relatively high. It is.

Density 80kl; thickness 50.7l/- by the above manufacturing method
Four types of products of 5° 100 mm and 150 mm were obtained.

Furthermore, the amount of water-repellent rock wool granular cotton added was 5% by weight.
A product of the present invention containing 20% by weight and a product without additive (conventional product) were manufactured by the same manufacturing method as above.

Each of these products was placed on a perforated plate, set so that the top surface of the perforated plate was located on the water surface, and allowed to absorb water naturally. The air content was measured based on the weight increase. The results are shown in Figure 2.

From the above results, the hydrophilic rock wool mat without water-repellent rock wool granular cotton had an air content of 5% or less at a thickness of 100 mm or less, whereas the hydrophilic rock wool mat with water-repellent rock wool granular cotton added had an air content of 5% or less. It is shown that even if the thickness of the invented product decreases as the amount added increases, the air content can be maintained in the range of 5 to 30%.

Next, the above water-repellent rock wool granular cotton content is 10% by weight.
product and a comparison product without additives, each with a thickness of 75a+
A block of 10,011 m in length and 10,011 m in width was made, and the peripheral side of the block was slightly tightened with a black polyethylene resin film to form a pot for raising seedlings. Then, 20 of each were prepared, one cucumber seed was sown in each, and the seedlings were raised using the constant drip irrigation method.The plants of the present invention were particularly taller than the control plants, and the inside of the leaf was larger. number of leaves,
There was no difference in leaf color or fruit length.

When the height of all 40 seedlings exceeds 3Gco+, the seedlings are grown to a thickness of 75+u+, a width of 300a+s,
7% So91G++++e (7) When placed on a hydroponic medium made of rock wool mat and grown using a circulating watering method, all 20 plants of the present invention grew well, whereas in the control Two plants suffered from root rot due to over-humidity, and the remaining 18 plants were also inferior to those of the present invention.

As described in detail, the mineral fiber mat for plant cultivation of the present invention has water retention, breathability, shape retention, and can maintain a good air content over a long period of time. It has extremely favorable effects as an artificial medium for use in the field.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of a mineral fiber mat for plant cultivation of the present invention, and FIG. 2 is a graph showing the results of a natural water absorption test between an example product of the present invention and a conventional product. 1...Main water-absorbing mineral fiber mat 2...Water-repellent mineral fiber granular cotton

Claims (1)

[Claims] The main body is a water-absorbing mineral fiber mat in which the constituent fibers are partially bonded to each other by an adhesive and a hydrophilic agent is added to the surface of the fibers, and water-repellent mineral fiber granular cotton is dispersed within the main body. A mineral fiber mat for plant cultivation characterized by containing mineral fiber.