JP2013144265A - Resin film treatment method, and method for evaluating agricultural chemicals resistance of the resin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin film treatment method capable of involving in the resin film, an assumable amount of sulfur in a protected horticulture in a short time.SOLUTION: The resin film treatment method includes immersing the resin film in a sulfite water having a concentration of 0.005-0.05N. Besides, a method for evaluating agricultural chemicals resistance of the resin film includes cleaning with water, the resin film treated by the above method, drying, irradiating with ultraviolet light for 500-2,000 hr, and comparing the tensile break strength of the film after the above irradiation to that before treatment.

Description

  The present invention relates to a method for treating a resin film.

Houses and tunnels for institutional horticulture are often used with a structure in which a resin film is stretched on a metal frame.
In greenhouse horticulture, inorganic sulfur agents are often used as agricultural chemicals. Under such circumstances, the resin film is likely to deteriorate, the tensile break elongation or tensile break strength of the resin film is significantly reduced, and the resin film is torn. May occur. In developing a resin film in which tensile elongation at break and tensile strength are not likely to decrease over a long period of time even in the above environment, a resin film that has been exposed to the above environment for a long time is simulated. It is necessary to measure the elongation at break and the tensile strength at break to evaluate the pesticide resistance.

  For example, in the example of Patent Document 1, a film is stretched in a test house, and after a fumigation treatment is performed for about 1000 hours using a sulfur fumigator, the film is irradiated with ultraviolet rays to obtain physical properties such as tensile strength at break. A method for measuring and evaluating pesticide resistance is described.

JP 2006-262904 A

  However, the method described in Patent Document 1 has a problem that it takes a very long time for the fumigation treatment.

  This invention provides the processing method of the resin film which can make the resin film contain the quantity of sulfur which can be assumed by facility gardening in a short time.

  That is, this invention relates to the processing method of the resin film which immerses a resin film in the sulfurous acid water whose density | concentration is 0.005-0.05N.

  The film processing method of the present invention can contain sulfur in the resin film in a short time.

  Hereinafter, embodiments of the present invention will be described in detail. This invention is a processing method of the resin film which immerses a resin film in the sulfurous acid water whose density | concentration is 0.005-0.05N.

  The resin film for the treatment of the present invention is preferably an agricultural film used for covering facilities such as houses and tunnels. Examples of the resin constituting the agricultural film include polyolefin resins, polyvinyl chloride resins, polyester resins such as polyethylene terephthalate, and fluorine-containing resins such as ethylene-tetrafluoroethylene copolymers. Among these, an agricultural film made of a polyolefin-based resin, which causes film breakage due to the use of agricultural chemicals, is preferable.

Agricultural film made of polyolefin resin includes a coating type agricultural polyolefin resin film in which at least one surface of a film made of polyolefin resin is coated with an antifogging coating or antifouling coating, and an interface with the polyolefin resin. Examples thereof include kneaded agricultural polyolefin-based resin films having a layer containing an activator.
The application type polyolefin resin film for agricultural use includes a polyolefin resin film coated with an antifogging coating on one surface, a polyolefin resin film coated with an antifouling coating on one surface, and an anti-fogging coating on one surface. Examples thereof include a polyolefin-based resin film coated with a cloudy film and having an antifouling film coated on the other surface.
When it is spread on the house, it is spread so that the surface on the inside of the house becomes an antifogging film. Moreover, it extends so that the surface which becomes the house outer side may become an antifouling film. In the invention, a coating type agricultural polyolefin resin film often used for long-term stretching is preferred.

  In the present invention, the resin film may be either a single layer or a multilayer. Moreover, 0.05-0.2 mm is preferable and, as for the thickness of a resin film, 0.1-0.15 mm is more preferable.

  Next, the sulfite water used in the present invention will be described.

  As the sulfite aqueous solution, a commercially available sulfite aqueous solution having a known concentration is adjusted to a concentration of 0.005 to 0.05 N by diluting with water as necessary. As commercially available sulfite water, for example, sulfite water having a concentration of 1.2 N manufactured by Wako Pure Chemical Industries, Ltd. can be used.

In the present invention, the film is immersed in sulfite water whose concentration is adjusted by the above method.
When an inorganic sulfur agent is used as a pesticide in facility horticulture, sulfur is oxidized by oxygen in the air, and the oxide adheres to the inner surface of the agricultural film. The sulfur oxide diffuses into the agricultural film. In agricultural films, hindered amine compounds are generally used as light stabilizers in order to suppress degradation due to light. However, the light stabilizers are deactivated by sulfur oxides, and Deterioration by light progresses, and mechanical properties such as tensile breaking strength and tensile breaking elongation may be reduced.
The degree of deterioration varies depending on the amount of sulfur oxide contained in the agricultural film, the temperature, humidity, and location in the house, but the minimum amount of sulfur oxide that causes the problem degradation is contained in the agricultural film. In terms of sulfur content, it is generally about 1,000 ppm or more.

  Moreover, there is an upper limit to the amount of agricultural chemicals used. The maximum amount of sulfur oxide that can be practically used is approximately 8,000 ppm or less in terms of the amount of sulfur contained in the agricultural film.

  In the present invention, the sulfur concentration contained in the resin film can be adjusted to 1,000 to 8,000 ppm by immersing the resin film in sulfite water having a concentration of 0.005 to 0.05 N. .

  The immersion time is preferably 1 to 48 hours, and the temperature of the sulfite water is preferably 10 to 30 ° C.

  In the present invention, a preferable range of the combination of concentration, immersion time, and temperature is a concentration of 0.02 to 0.04 normal, an immersion time of 12 to 36 hours, and a temperature of 20 to 25 ° C., and a more preferable range is The concentration is 0.02 to 0.04 normal, the immersion time is 20 to 28 hours, and the temperature is 20 to 25 ° C.

The film processing method of the present invention can be used as a processing method for rapidly developing an agricultural film having excellent pesticide resistance. Conventionally, an agricultural film is stretched in a house, sulfur fumigation is performed for a long period of time, and a treatment for including a predetermined amount of a sulfur compound in the film has been performed. A treatment can be performed in which a predetermined amount of a sulfur compound is contained in the film.
The resin film treated by the above method is washed with water and dried, and then the tensile break strength of the resin film after ultraviolet irradiation for 500 to 2000 hours, and the tensile strength of the resin film before being treated by the above method The agricultural chemical resistance of the resin film can be evaluated by comparing the breaking strength.

  Examples of the present invention will be described below. In addition, the test method in an Example and a comparative example is as follows.

(1) Sulfur content in the film The sulfur content in the film was measured by ion combustion chromatography.

[Example 1]
<Dipping film in sulfite water>
Sulfurous water having a concentration of 1.2 N (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) was diluted with ion-exchanged water to obtain a sulfurous acid water having a concentration of 0.02 N
A commercially available agricultural film CLINTATE EX 130 μm thick was immersed in the 0.02 N aqueous sulfite solution for 24 hours. After immersion, the film was taken out from the sulfite water, and the film surface was washed with ion exchange water. And it was naturally dried for 24 hours.
In addition, adjustment of sulfurous acid water, film immersion, washing, and natural drying were performed in a temperature-controlled room at a temperature of 23 ° C. and a relative humidity of 50%.
The sulfur content in the film is shown in Table 1.

[Example 2]
<Immersion in sulfite water>
The same procedure as in Example 1 was conducted, except that the concentration was adjusted to 0.04N.
The sulfur content in the film is shown in Table 1.

Example 3
<Immersion in sulfite water>
The same procedure as in Example 1 was carried out except that the concentration was adjusted to 0.05N.
The sulfur content in the film is shown in Table 1.

Example 4
<Dipping film in sulfite water>
It was carried out in the same manner as in Example 1 except that the soaked film was changed to a commercially available agricultural film Diastar 150 μm thick.
The sulfur content in the film is shown in Table 1.

Example 5
<Dipping film in sulfite water>
The same procedure as in Example 2 was performed except that the soaked film was changed to a commercially available agricultural film Diastar 150 μm thick.
The sulfur content in the film is shown in Table 1.

[Comparative Example 1]
<Immersion in sulfite water>
The same procedure as in Example 1 was performed except that the concentration was adjusted to 0.08 N by diluting the concentration of sulfite water.
The sulfur content in the film is shown in Table 1.

[Comparative Example 2]
<Immersion in sulfite water>
A commercially available agricultural film CLINTATE EX 130 μm thick was immersed in a 1.2N concentration sulfite water (manufactured by Wako Pure Chemical Industries, Ltd., reagent special grade) for 4 hours. After immersion, the film was taken out from the sulfite water, and the film surface was washed with ion exchange water. And it was naturally dried for 24 hours.
In addition, adjustment of sulfurous acid water, film immersion, washing, and natural drying were performed in a temperature-controlled room at a temperature of 23 ° C. and a relative humidity of 50%.
The sulfur content in the film is shown in Table 1.

[Reference example]
<Sulfur fumigation of film>
In a test house in Sahara City, Chiba Prefecture, a commercially available agricultural film CLINTATE EX 150 μm was used as a covering material, and the film was covered on the frame so that the inside of the house was kept in a sealed state.
A sulfur fumigator with a timer (trade name: Super Smoky, manufactured by Daishin Oil Chemical Co., Ltd.) was installed in the house, and sulfur fumigation treatment was performed for 4 months at a frequency of 5 hours / day. Thereafter, the film was removed from the test house, and the sulfur content in the film was measured.
The sulfur content in the film is shown in Table 2.

  The film processing method according to the present invention can be used as a test method for developing an agricultural film having excellent pesticide resistance.

Claims (3)

  A method for treating a resin film, wherein the resin film is immersed in sulfite water having a concentration of 0.005 to 0.05 N.   The method for treating a resin film according to claim 1, wherein the temperature of the sulfite water is 10 to 30 ° C and the immersion time is 1 to 48 hours.   The resin film treated by the method according to claim 1 or 2 is washed with water, dried, and further subjected to ultraviolet irradiation for 500 to 2000 hours. A method for evaluating the pesticide resistance of a resin film by comparing the tensile rupture strength of the resin film before treatment with the method described.