JP4766802B2 - Agricultural multi-film and crop cultivation method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an agricultural multi-film that does not require disposal after the use of the multi-film.
[0002]
[Prior art]
Conventionally, when looking at the actual situation of multi-cultivation, as shown in FIG. 2, a strip-shaped film 10 is covered from the upper surface to the side surface of the ridge 11 (usually about 50 to 100 m in length and about 10 to 15 cm in height). The soil 12 is placed on the side surface so that the film is not scattered by wind or the like. Therefore, when the multi-film 10 is viewed along the longitudinal direction, the multi-film 10 is divided into a ground region 13 (ground surface region) where cultivated crops are vegetated and a soil subregion 14 (ground region) for preventing scattering. It will be.
[0003]
In such a multi-film, there are problems of film removal work after plant cultivation and film regeneration processing. In order to solve such problems, the present inventor previously disclosed a polyethylene resin or the like in Japanese Patent Application No. 10-193694. An agricultural multi-film was proposed in which both sides of a thermoplastic resin film were formed from a biodegradable resin.
[0004]
However, when such a multi-film is integrally formed by an inflation molding method, which is a general film forming method, for example, low-density polyethylene is used as a resin for the ground region (surface row region), and the soil region (soil row region) In the case of using a biodegradable resin for the resin (1), since the polarity of the low-density polyethylene is small and the polarity of the biodegradable resin is large, there is a problem that it is difficult to bond the ground row region and the soil row region on both sides thereof. In addition, there is a difference in melt tension between low-density polyethylene and biodegradable resin, and there is a problem that uniform blow-up cannot be performed and thickness control cannot be performed.
[0005]
In addition, if all the resin in the ground region and the soil region are formed using the same biodegradable resin, there is a difference in the film decomposition and deterioration rates between the soil and the ground surface, and there are the following problems.
[0006]
In the case of using a biodegradable resin, the soil region film is biodegraded by microorganisms in the soil, and almost disappears at the end of one crop (2 to 6 months). There is a problem of being broken in 3 months.
[0007]
In addition, when using a resin with slow biodegradability, biodegradation by soil microorganisms does not proceed in the soil region, and if the film remains in the soil, there is a problem that inconveniences the next cropping and growth, Since the film in the ground area has a high residual strength, there is a problem of entanglement with the rotor when the film is squeezed into the soil with a rotary tiller.
[0008]
In particular, the above-ground film does not disappear in a short period (1 to 2 weeks) even if it penetrates into the ground, and it is difficult to immediately move on to the next film. That is, the remaining film becomes an obstacle in the seeding and planting work, which causes a problem in work. What is most worrisome is that it puts a burden on the ecosystem in the field and makes the field a garbage dump.
[0009]
[Problems to be solved by the invention]
Therefore, the present invention provides an agricultural multi-film and a crop cultivation method that make film life different between the above-ground part and the soil part, match the actual situation of crop cultivation, and facilitate film waste disposal after the cultivation is completed. This is the issue.
[0010]
[Means for Solving the Problems]
The agricultural multi-film according to the present invention that solves the above-mentioned problems is a strip-shaped agricultural multi-film, having a ground area in the center along the longitudinal direction of the film, on one side or both sides of the ground area. The ground region film and the soil region film are biodegradable resins having different biodegradability, and the soil region film is more than the ground region film. It is characterized in that it is a biodegradable resin that is biodegraded as soon as possible. Preferably, the film in the soil middle region is made of a biodegradable resin that is maintained without being biodegraded for two months from the start of crop cultivation and then biodegraded. More preferably, the above-mentioned film in the above-ground region is made of a biodegradable resin that biodegrades under conditions of temperature and humidity for composting.
[0011]
The crop cultivation method according to the present invention for solving the above-mentioned problems is a crop cultivation method using the above-described agricultural multi-film, wherein after the film in the subterranean area is biodegraded, It is characterized by preventing the film in the region from scattering. Or a method for cultivating a crop using the above-described agricultural multi-film, wherein after the film in the soil region is biodegraded, the film in the ground region is prevented from being scattered by the crop itself, After the cultivation, the above-mentioned film in the above-ground area is composted at a predetermined temperature and humidity.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
[0013]
As shown in FIG. 1, the agricultural multi-film according to the present invention has a ground area 1 at the center along the longitudinal direction of the film, and has soil areas 2, 2 on both sides of the ground area 1. ing.
[0014]
The first characteristic of the film in the ground area 1 is made of biodegradable resin that does not deteriorate and break until the end of crop cultivation, and the second characteristic does not deteriorate and break until the end of crop cultivation. It is made of biodegradable resin that is mixed with compost raw materials (eg, straw, vegetable residues, livestock manure, etc.) and biodegraded under composting temperature and humidity conditions.
[0015]
Until the end of crop cultivation in the first feature, it is 2 to 6 months from the start of cultivation. The cultivation period (film use period) varies depending on the type of crop, the cultivation period, the cultivation method (such as open field, tunnel, and house cultivation), the cultivation area, and the like. In other words, the cultivation period varies even with the same crop. Specifically, type 2 (2 months from the start of cultivation), type 3 (3 months from the start of cultivation), type 4 (4 months from the start of cultivation), type 5 (5 months from the start of cultivation), type 6 (from the start of cultivation) It is preferable to prepare a type for each service life, such as 6 months). Moreover, it is also possible to prepare by type every 0.5 months, such as 3.5 type (3.5 months from the start of cultivation), not monthly.
[0016]
Deterioration damage means that the film has been deteriorated and damaged to such an extent that it loses its residual strength when it is rubbed into the soil with a rotary tiller and cannot be entangled with the rotor. As specified in the characteristics, it is a degree of biodegradation under the conditions of composting after the end of crop cultivation.
[0017]
As characteristics of the film, there is also an influence of deterioration and damage due to ultraviolet rays when it is present on the ground part. Therefore, it is preferable to allow for the deterioration and to cause the second characteristic biodegradation.
[0018]
The temperature and humidity for composting are, for example, the temperature and humidity at which food waste is composted, and the temperature is preferably about 60 to 90 ° C., and the humidity (relative humidity) is, for example, 50% RH to 100% RH. A range is preferred. Therefore, when compost fertilizer is produced using raw garbage or the like as raw material, it is preferable that the film characteristics of the above-ground region 1 are such that compost can be produced under the same conditions by mixing the raw material 1 film with the raw material. That is, it is preferable that the film of the ground area 1 has a compostable property.
[0019]
Hereinafter, biodegradable resins that are raw materials for producing the film of the above-ground region 1 are polylactic acid, polycaprolactone, polyethylene succinate, polybutylene succinate, polybutylene succinate adipate, polyhydroxybutyrate, Aliphatic polyesters such as polyester carbonate, polyhydroxybutyrate / hydroxyvalerate, aliphatic aromatic polyester copolymers, cellulosic resins such as polycellulose acetate, modified polyvinyl alcohol, and starch, wood flour, and insulator The mixture with organic fine powders, such as shell powder, the mixture with inorganic fine powders, such as calcium carbonate and silicon dioxide, the thing which mix | blended coloring pigments, such as titanium dioxide, carbon black, and aluminum powder.
[0020]
Next, the films in the subterranean regions 2 and 2 have the property of being maintained without being biodegraded for 2 months from the start of crop cultivation and then biodegraded. It is during the first two months of growth that the film in the ground area 1 exhibits the multi-effect. Therefore, it is necessary to suppress the film in the soil middle region with soil for the first two months of growth, and the film in the ground region 1 should be firmly spread on the surface.
[0021]
And after 2 months, even if the film in the subterranean area 2 is biodegraded, the crop itself becomes large and prevents the film from being scattered by wind or the like. In other words, it is in a state where it is hung on the surface, that is, a so-called sticky state. On the other hand, the subterranean region 2 is biodegraded quickly and has no problem of remaining film, and only in the subterranean region 2, it is preferable because there are no problems on the soil and contamination.
[0022]
Below, when the biodegradable resin used as a raw material at the time of manufacturing the film of the soil subregion 2 is given, the target decomposable one is selected from the same resin as the ground region 1. A resin having a slow degradability is designed to have a desired degradability by mixing it with an organic fine powder or an inorganic fine powder.
[0023]
In the present invention, the ground region 1 film is preferably blended with a color pigment, and the soil region 2 film is preferably unblended or blended with organic and inorganic fine powders. The thing which mix | blended was preferable.
[0024]
As a manufacturing method of the agricultural multifilm of this invention, it can form by three rows simultaneous extrusion using the above-mentioned raw material and using an inflection die, a T die, etc.
[0025]
As for the thickness of the agricultural multi-film of this invention, about 3-50 micrometers is preferable, More preferably, it is the range of 5-35 micrometers.
[0026]
Furthermore, in the agricultural multifilm of the present invention, conventionally known surfactants, weathering stabilizers, ultraviolet absorbers, lubricants, antiblocking agents and the like can be added.
[0027]
The agricultural multi-film of the present invention may be a black or silver colored film layer having an appropriate color density. In particular, carbon black powder as a black pigment has a porous surface structure and is chemically active, and can modify the light resistance and biodegradability of various biodegradable resins. Specifically, it absorbs sunlight energy to make it harmless heat energy, prevents deterioration of the biodegradable resin, and adjusts the blending amount to increase the weather resistance of the original biodegradable resin by several tens to several times Can be improved. Degradability can be delayed in the soil. Although the mechanism is not clear, it is presumed that an enzyme that promotes decomposition is adsorbed and controlled to gradually decompose.
[0028]
Moreover, you may give a means to suppress the flying of various pests.
[0029]
As described above, in the embodiment of the agricultural multi-film of the present invention, the example in which the soil sub-regions 2 and 2 are provided on both sides of the ground sub-region 1 has been described. The effect of the present invention can be exerted even when it is on the side.
[0030]
【The invention's effect】
According to the present invention, there are provided an agricultural multi-film and a crop cultivation method in which film life is made different between the above-ground part and the soil part to match the actual situation of crop cultivation, and the film waste treatment is facilitated after the cultivation is completed. be able to.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an agricultural multi-film according to the present invention. FIG. 2 is a cross-sectional view showing an example of use of an agricultural multi-film.
1: Ground area 2: Soil area

Claims (5)

In a strip-shaped agricultural multi-film, it has a ground area in the center along the longitudinal direction of the film, and has a soil area on one side or both sides of the ground area,
The above ground region film and the above soil region film are biodegradable resins having different biodegradable performances from each other,
The agricultural multi-film is a biodegradable resin that is biodegradable faster than the above-ground film. The agricultural multi-film according to claim 1, wherein the film in the subterranean region is made of a biodegradable resin that is maintained without being biodegraded for two months from the start of crop cultivation and then biodegraded. The agricultural multi-film according to claim 1 or 2, wherein the film of the above-ground area is made of a biodegradable resin that biodegrades under composting temperature and humidity conditions. A crop cultivation method using the agricultural multi-film according to claim 1,
A method for cultivating a crop, comprising preventing the above-ground film from being scattered by the crop itself after the soil film is biodegraded. A crop cultivation method using the agricultural multi-film according to claim 3,
After the film of the subterranean area is biodegraded, the film of the ground area is prevented from scattering by the crop itself,
A crop cultivation method comprising composting the above-ground film at a predetermined temperature and humidity after completion of crop cultivation.

Images