JPS6240965B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a plastic sheet having a large number of convex protrusions forming independent air chambers and having a large number of openings in locations other than the convex protrusions. (Hereinafter also referred to as a protrusion sheet with openings)
This relates to a special hotbed used as a hotbed for raising rice seedlings.

In recent years, in order to save labor in farming, it has become popular nationwide for farmers to use rice transplanters to transplant rice. It is becoming important to grow seedlings with good reproducibility in response to climate changes.

Normally, the rice seedlings are raised in a hotbed greenhouse, with appropriate nourishing soil placed in a seedling box with an opening in the bottom and a bottom area suitable for the rice transplanter, and the seeds are sown in the nourishing soil. Seedling boxes were placed directly on the surface of the ground in a hotbed, the temperature inside the greenhouse was adjusted, and water was sprinkled on the boxes as needed to cause germination and raise the seedlings.

In the above-mentioned raising of rice seedlings, there are various factors such as adjusting the moisture content (degree of humidity) and oxygen content in the seedling box, irradiating the rice seedlings with sunlight, and adjusting the temperature inside the greenhouse.
All of these are important, and if they are not carried out in harmony, it will not be possible to transplant rice properly using a rice transplanter, and it will not be possible to obtain rice seedlings with well-balanced leaves, stems, and roots that will grow robustly after transplanting. be.

However, in the conventional rice seedling raising process described above, the temperature of the ground in the hotbed that the seedling box is in contact with drops significantly due to heat conduction in the ground as the temperature of the ground outside the hotbed decreases. Therefore, heat is taken away from the area around the seedling nursery box, and in the end, the rice seedlings in the nursery box do not grow uniformly or do not grow sufficiently in a short period of time. It often happens that the rice seedlings are not able to be transplanted using the machine, or that the rice seedlings fall over or wither after planting. The above-mentioned phenomenon was particularly noticeable in cold regions, and even in warm regions where temperature changes between day and night were dramatic.

The inventors have proposed a hotbed for raising rice seedlings that can avoid being adversely affected by a drop in the temperature of the ground in the hotbed, and can harmoniously satisfy the conditions for raising rice seedlings described above. As a result of various studies, we arrived at the hotbed for raising seedlings of this invention.

This invention provides a greenhouse with a large number of convex protrusions forming independent air chambers between the bottom of a rice seedling nursery box and the ground surface of the hotbed. This invention relates to a hotbed for raising seedlings, in which a plastic sheet having a large number of openings in locations other than the protrusions is arranged along the surface of the ground (ground surface).

If rice seedlings are raised in the hotbed of this invention, even in cold regions or regions with large temperature differences between day and night, the excellent heat insulation properties of the protruding sheets with perforations placed on the ground surface of the hotbed will help. Therefore, the temperature near the seedling box in the hotbed does not drop significantly, so the rice seedlings grow uniformly and quickly.

In addition, in this invention, the protruding sheet with openings is a flexible cushioning sheet made of plastic, so it is resistant to moisture and bacteria in the ground, and even if the ground of the hotbed is slightly uneven. Furthermore, due to the drainage and air permeability of the numerous openings of the projection sheet, excess water drained from the bottom of the seedling box remains under the bottom of the seedling box. This is suitable because water can be drained into the ground through the pores without impeding air permeability.

Furthermore, the hotbed for raising seedlings of the present invention can be made by a simple operation using the above-mentioned projection sheet with openings and the seedling raising box (including soil), and its maintenance is easy.

Hereinafter, the hotbed for raising seedlings of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a sectional view showing an example of a situation in which a hotbed for raising seedlings of the present invention is formed in a hotbed house and rice seedlings are raised, and FIG. FIG. 2 is an enlarged cross-sectional view of an example of a hot bed.

FIG. 3 is a perspective view showing an example of a protrusion sheet with apertures, and FIG. 4 is a sectional view of the protrusion sheet. FIG. 5 is a sectional view showing another example of the protrusion sheet with openings.

As shown in FIG. 1 and FIG.
This relates to a hotbed for raising seedlings, in which a protrusion sheet 6 with perforations is arranged along the ground surface 3 between the bottom surface of the hotbed and the surface 3 of the ground 5 of the hotbed.

As shown in FIGS. 3 to 5, the perforated protrusion sheet 6 according to the present invention is provided with a large number of convex protrusions 8 arranged to form independently sealed air chambers 7. and the convex protrusion 8
This is a plastic sheet with a large number of holes 9 provided in locations other than the .

Such a protrusion sheet 6 with apertures is, for example,
A plastic sheet having a large number of convex protrusions forming independent air chambers (hereinafter referred to as Any material may be used as long as it is manufactured by providing a large number of drainage and ventilation holes in a protrusion sheet (sometimes simply referred to as a protrusion sheet).

To describe in detail a specific example of the method for manufacturing the projection sheet, for example, a first sheet of raw material film that has been heated and softened is wound around an embossing roll having a large number of recesses, and the raw material film is brought into close contact within the recesses. A convex protrusion is formed on the first raw material film, and then a second heated and softened raw material film is wrapped around the first film on which the protrusion is formed, and the protrusion on the first film is formed. A preferred method is to manufacture the protrusion sheet by thermally adhering a second raw film (back film) to the other surface.

Any method may be used to form a large number of perforations in the protrusion sheet produced by the above method. For example, in the production of the protrusion sheet described above, convex When a second raw material film is overlaid and thermally bonded to the first film on which the protrusions have been formed, a large number of holes are regularly opened in locations other than the protrusions almost simultaneously with the adhesion. The method is preferred.

In this invention, the protrusion sheet with apertures includes:
A third raw material film 10 (preferably a film having a large number of perforations 12) is added to the perforated protrusion sheet formed from the two raw material films by the method described above, which is further heated and softened. ) may be a protrusion sheet with apertures (see FIG. 5) consisting of three raw material films which are overlapped and thermally bonded from the tips of the protrusions of the protrusion sheet with apertures.

Alternatively, as a projection sheet with holes, a metal thin film (for example, metal foil, metal vapor deposited film, etc.) or a plastic film with metal thin film is adhered to a projection sheet with holes made of two or three raw films. It may also be attached through an agent layer.

In this invention, the convex projections of the perforated projection sheet have air chambers formed in shapes such as prismatic, cylindrical, elliptical, semicircular, or a combination thereof. Good to have. especially,
Its convex protrusion has a height of 3 to 20 mm, especially 4 to 18 mm.
mm, furthermore, about 8 to 15 mm, and the base area is 0.2 mm.
It is preferable that an air chamber is formed in a columnar shape, such as a columnar shape or an elliptical columnar shape, with a size of about 15 cm 2 to 15 cm ² , especially about 0.5 to 10 cm ² . In this invention, if the height of the convex projection becomes too low, the bottom of the seedling growing box will approach the ground, which is undesirable since the insulation effect will be lost.

The perforated protrusion sheet preferably has a large number of convex protrusions arranged over the entire surface such that the interval between the convex protrusions is about 2 to 20 mm, particularly about 4 to 15 mm.

In this invention, the protrusion sheet with apertures must have an aperture that penetrates the protrusion sheet from the front to the back, except for the protrusion. In this invention, for example, the diameter is 0.5~
It is preferable to have a substantially circular or oval opening with a diameter of about 5 mm, particularly 1 to 4 mm.

In this invention, the plastic raw material film forming the perforated projection sheet is an addition polymer of polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, etc.
Molded from thermoplastic resins such as condensation polymers such as nylon and polyester, with a thickness of 20 to 500μ, especially
Any plastic film of about 30 to 300μ will suffice.

In this invention, the seedling box 2 for rice seedlings 4 shown in FIG. 2 is for growing a collection of rice seedlings (having a rectangular bottom) that can be transplanted using a known rice transplanter. It may be of any known type as long as it is a wooden or plastic box having a number of drainage or ventilation holes at the bottom.

In this invention, there is no particular limitation on the state in which the projection sheet 6 with perforations is laid along the ground surface 3 between the seedling raising box 2 for the rice seedlings 4 and the ground 5 of the hotbed. However, as shown in FIG. 1, it is preferable that the ends of the perforated protrusion sheets 6 are raised up along the vertical walls of the hotbed house 1 at the corners of the hotbed house 1. In addition, when using a sheet made of two raw material films as shown in Figs. 3 and 4 as the perforated protrusion sheet, the sheet should be laid with the tips of the convex protrusions 8 facing downward. This prevents the formation of an unnecessarily large gap between the bottom of the seedling nursery box 2 and the protrusion sheet with openings, and therefore prevents the bottom of the seedling nursery box 2 from drying out and prevents the roots of the rice seedlings. It is suitable for the growth of.

In addition, in this invention, if the seedling raising box 2 and the upper surface of the protruding sheet 6 with openings come into too close contact with each other, it is not preferable from the viewpoint of drainage and ventilation. It is preferable that a necessary narrow gap is formed. For example, as shown in FIG. 2, a seedling raising box 2 having legs 11 projecting downward is used at a part of the bottom of the seedling raising box 2. It is preferable that

If rice seedlings are raised in the hotbed of this invention, the rice seedlings will grow uniformly and quickly even in cold regions.

In addition, in the hotbed of the present invention, even if the seedling raising box 2 is watered a little excessively, the excess water is drained, so there is no need to water a small amount many times, and it is also possible to adjust the temperature inside the hotbed. It also eliminates the need for frequent heating, which has the effect of reducing agricultural work.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a situation in which a hotbed for raising seedlings of the present invention is formed in a hotbed house and rice seedlings are raised, and FIG. FIG. 2 is an enlarged cross-sectional view of an example of a hot bed.
FIG. 3 is a perspective view partially showing an example of a protrusion sheet with apertures, and FIG. 4 is a sectional view of the protrusion sheet. FIG. 5 is a sectional view showing another example of the protrusion sheet with openings. 1; hotbed house, 2; seedling raising box, 3; ground surface (ground surface), 4; rice seedlings, 5; ground, 6; projection sheet with openings, 7; air chamber, 8; convex projections, 9; Opening portion, 10; Third film, 11; Leg portion.

Claims (1)

[Claims] 1. In the hotbed greenhouse, there are many convex protrusions that form independent air chambers between the bottom of the rice seedling nursery box and the ground surface of the hotbed, and the convex protrusions are A hotbed for raising seedlings in which a plastic sheet with many openings is placed along the ground surface.