JPH02303421A - Mat for raising seedling of paddy rice plant - Google Patents

Abstract

PURPOSE:To obtain mat for raising seedling of paddy rice plant having high voids, excellent air permeability and water retention and to promote growth of seedling by using mat comprising specific rock wool, having fibers arranged in the direction in parallel to mat surface and fixed bulk density for raising of seedling of paddy rice plant. CONSTITUTION:Rock wool having >=3cm average fiber length and <=40wt.% shot content is collected on a fiber collecting face traveling in the horizontal direction while being sprayed with a phenol resin-based hinder to give mat comprising fibers arranged in parallel to the mat face and having 40 to 70kg/m<3> bulk density. Then the mat is used for raising of seedling of paddy rice plant to promote raising of seedling of paddy rice plant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mat used as a seedbed for growing paddy rice seedlings.

[Conventional technology]

In recent years, as the use of rice transplanters to plant paddy rice seedlings has become widespread, there is a shortage of soil needed for seedbeds for growing paddy rice seedlings, and materials other than those provided by fasteners have often been used. A typical seedbed material that has been conventionally provided as an alternative to soil is a mat made of inorganic fibers such as rock wool. An example of this is disclosed in Japanese Patent Application Laid-Open No. 60-141217, in which the fibers are mainly arranged in a direction perpendicular to the mat surface so that roots can grow well.

However, mats in which the fibers are arranged in a direction perpendicular to the mat surface (hereinafter referred to as vertically arranged mats) tend to tear easily and cannot withstand handling during rice planting before use or after raising seedlings. Conventional seedling raising mats using vertically arranged mats have reinforcing paper glued to the surface opposite to the seeding surface.

[Problem to be solved by the invention]

Conventional mats for growing rice seedlings made of vertically arranged mats as described above have the drawback of being expensive due to the complicated manufacturing process. In other words, it is not possible to directly manufacture a vertically arranged mat from the raw material fibers, but by accumulating the fibers on the surface of a wire mesh conveyor running in an oven, a mat in which the fibers are mainly arranged in a direction parallel to the mat surface is manufactured. After that, it is necessary to make a laminate by stacking many of these sheets, and then cut the laminate thinly along a plane perpendicular to the fiber orientation direction to produce a vertically arranged mat. This required a layering process, resulting in high manufacturing costs. Another problem is that when used as a seedbed, the reinforcing paper not only inhibits root growth, but also gets in the way of the rice transplanter removing seedlings one by one from the seedlings that have grown in clusters on the mat. There was also.

An object of the present invention is to solve the above-mentioned problems of conventional mats for raising rice seedlings.

(Another means to solve the problem) The mat for raising rice seedlings provided by the present invention has an average fiber length of 3
A rock wool mat with a fiber content of 1 or more and a fiber content of 40% by weight or less, the fibers are arranged in a direction substantially parallel to the mat surface, and the bulk density is 40 to 70 kg/m'
It is characterized by

The present invention provides a rock wool mat with a bulk density of 4
This is based on the new finding that if it is 0 to 70 k (/m'), root growth is good even without a vertically arranged mat.The average fiber length of the fibers is as long as 3 cm or more,
The seedling raising mat of the present invention, which is made of rock wool with few stains and whose fibers are arranged in a direction parallel to the mat surface, inherently has the strength to withstand normal handling up to rice planting. The paper is not laminated.

Hereinafter, six typical methods for producing the mat for growing rice seedlings of the present invention will be explained.

First, the fiber-forming mineral raw material is melted and made into fibers by a conventional method. By selecting raw materials and fiber-making conditions that give a melt with good spinnability, long fibers with an average length of 3 caps or more can be formed. Allows wool to be obtained. The formed rock wool is conveyed onto a conveyor-like la that runs directly under the fiber manufacturing equipment.
(If the 1a fibers contain more than 40% by weight of stains, it is necessary to insert a step to remove them). At this time, if a vortex air current is applied to the falling fibers to cause some of the fibers to bend or curl,
The intertwining between the fibers improves, increasing the strength of the mat. The falling fibers are also sprayed with a binding agent. As the binder, one made of phenol resin, urea resin, etc. can be used. If necessary, apply fertilizer at this time, p.
Acid for H adjustment is also sprayed. The bulk density of the product is adjusted to 40 to 70 kl/1 by adjusting the amount of the binder and the like and the vertical distance between the ovens.

Since the fiber collecting surface is running, the mat formed on the collecting surface has most of the fibers arranged in a direction parallel to the mat surface.

The mat for raising seedlings of the present invention is obtained by heating the continuously formed mat to harden the binder and then cutting it into an appropriate size.

〔Example〕

Example 1 40% pig iron slag, 50% basalt, and dolomite lO
% was melted in a cupola and made into fibers by a conventional method. The obtained rock wool has an average fiber length of 10
0Otori11 It had a cimitto content of 38%.

By collecting this on a horizontally running fiber collection surface while spraying a vortex air stream and a phenolic resin binder (2% by weight based on the fibers), the fibers are mainly arranged in a direction parallel to the surface. In addition, a part of the mat was bent or curled.

This was heated to 250° C. under pressure and open to harden the binder, and a mat with a bulk density of 50 k(/m′) was obtained.

This mat was actually used to raise paddy rice seedlings, and the growth of the seedlings and adaptability to rice transplanters were investigated. Apply an appropriate amount of basal fertilizer to the seedling mat, and transplant rice using a rice transplanter 35 days after sowing.

For comparison, seedlings were raised using conventional seedbeds made of vertically arranged mats and seedbeds made of rice paddies.

The results are shown in Tables 1 and 2, confirming the excellent performance of the seedling growing mat according to the present invention.

Table 1 Seedling Growth Table 2 Applicability of Rice Planting Machines Incidence of defective plantings with an angle of inclination of 60 degrees or more from the vertical [Effects of the Invention] The seedling raising mat of the present invention is based on the above-mentioned structure, Easy to manufacture and inexpensive; ■ High porosity (approximately 97% or more), good air permeability and water retention, so germination, rooting, and subsequent root growth are quick, and seedlings grow well. It has many features such as: - Smooth scraping by the rice transplanter, uniform number of plants, and good planting posture;

Claims (2)

[Claims] (1) Average fiber length is 3 cm or more and shot content is 40
% by weight or less, the fibers are arranged in a direction substantially parallel to the surface of the mat, and the mat has a bulk density of 40 to 70 kg/m^3. (2) The mat for growing rice seedlings according to claim 1, wherein a portion of the rock wool constituting the mat is bent or curled.