JPH0761222B2 - Agricultural film or sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to an agricultural film that controls pests and disease fungi and does not inhibit the color development of vegetables, fruits and flowers in covering cultivation of vegetables, fruits and flowers. Or regarding the seat.

<Prior art> In recent years, with the spread and development of cover cultivation, harmful pests have spread to the crops and parasitize them, causing serious damage.In particular, the southwestern warm regions of Okinawa, Kyushu, Shikoku, etc. In recent years, the damage caused by Thrips palmi and Aphids has become a serious problem in China, Kinki and Tokai regions.

In order to control these pests, a method of covering crops with a film that cuts near ultraviolet rays has been proposed and put into practical use.

For example, JP-B-48-37459, JP-B-49-16301, JP-B-51-43850, JP-B-53-47383, JP-B-55-10203
And Japanese Patent Publication Nos. 55-12208 and 56-46375.

<Problems to be Solved by the Invention> However, although these methods are effective in controlling crop pests and disease fungi, they have a problem that eggplants and flowers are poorly colored and cultivated crops are limited.

An object of the present invention is to provide an agricultural film or sheet that has excellent control effects against crop pests and disease fungi in cover cultivation of crops and that does not inhibit coloring of crops that require coloring such as eggplants and flowers. It is in.

<Means for Solving Problems> The inventors of the present invention have conducted extensive studies to achieve the above-mentioned object, and among the spectral transmission energy under natural light, ultraviolet rays having a wavelength of 380 nm or less are substantially opaque. And
Wavelengths of 510 nm to 600 nm are absorbed without blocking the transmission of visible light of 400 nm to 500 nm.
Amplifies the transmission of visible light from 600nm to 700nm, wavelength 400 to 500
A red-colored agricultural film or sheet characterized by a ratio of the average transmittance of nm to the average transmittance of wavelengths of 600 to 700 nm of less than 1 comes into a house or tunnel covering it. The present inventors have found that the pests are controlled, the propagation of disease bacteria is suppressed, and the eggplants and flowers are colored well, resulting in the present invention.

That is, the agricultural film or sheet of the present invention is obtained by forming a thermoplastic resin composition containing a thermoplastic resin, an ultraviolet absorber and a fluorescent colorant into a film or sheet.

The thermoplastic resin used in the present invention is not particularly limited, but examples thereof include ethylene homopolymers such as low density polyethylene and high density polyethylene, ethylene-butene 1 copolymer, ethylene-4-methyl-pentene-1. Ethylene-α-olefin copolymers such as copolymers, ethylene-hexene copolymers, ethylene-octene copolymers, ethylene-vinyl acetate copolymers, ethylene-acrylic acid copolymers, ethylene-vinyl acetate-methyl A methacrylate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene copolymer, etc. are possible, and a polypropylene vinyl chloride resin, a polymethylmethacrylate resin, a polyester resin, a polycarbonate resin, etc. can be used. These can be either alone or glass fiber reinforced It is possible to use.

In the present invention, of the spectral transmission energy under natural light, ultraviolet rays having a wavelength of 380 nm or less can be made substantially non-transparent, and can be obtained by blending a commonly used ultraviolet absorber.

The ultraviolet absorber used in the present invention may be any material as long as it absorbs ultraviolet rays having a wavelength of 380 nm or less in the spectral transmission energy under natural light, and examples thereof include the following compounds.

Hydroquinone-hydroquinone, hydroquinone disalicylate salicylic acid-phenyl salicylate, para-octylphenyl salicylate benzophenone-2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2- Hydroxy-4-methoxy-
2'-carboxybenzophenone, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-benzoyloxybenzophenone, 2,2'-hydroxy-
4-methoxybenzophenone, 2-hydroxy-4-
Methoxy-5-sulfonebenzophenone, 2,2 ', 4,4'
-Tetrahydroxybenzophenone etc.

Benzotriazole-based-2 (2'-hydroxy-5 '
-Methylphenyl) benzotriazole, 2 (2'-hydroxy-5'-methylphenyl) 5,6-dichlorobenzotriazole, 2 (2'-hydroxy-5-tert-butylphenyl) benzotriazole, 2
(2'-Hydroxy-3'-methyl-5'-tert-butylphenyl) benzotriazole, 2 (2'-
Hydroxy-3 ′, 5′-ditertiary-butylphenyl-5-chlorobenzotriazole, 2 (2′-hydroxy-5′-phenyl-5-5-chlorobenzotriazole, 2 (2′-hydroxy-3′-tertiary −
Butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2 (2'-hydroxy-4'-octoxydiphenyl) benzotriazole and the like.

Of these, benzophenone-based and benzotriazole-based are preferable in terms of high near-ultraviolet absorption, and among them, 2,
2'-dihydroxy-4-methoxy-benzophenone, 2 (2'-hydroxy-5'-methylphenone)
Benzotriazole, 2 (2'-hydroxy-3'-
Tertiary-butyl-5'-methylphenyl) -5-chlorobenzotriazole is particularly preferable because it has good compatibility with the thermoplastic resin and can obtain high ultraviolet absorption with a small amount.

Next, in the present invention, among the spectral transmission energy under natural light, without inhibiting the transmission of visible light having a wavelength of 400 nm to 500 nm, and absorbing visible light having a wavelength of 510 to 600 nm, visible light having a wavelength of 600 nm to 700 nm. In order to amplify the transmission of light, it is achieved by using a fluorescent colorant capable of wavelength conversion of light.

Illustrating the fluorescent colorant used in the present invention, a coumarin-based dye represented by the following structural formula, A xanthene-based dye represented by the following structural formula, a thioxanthene-based dye, A benzopyran dye represented by the following structural formula, A naphthalimide-based or naphtholactam-based dye represented by the following structural formula, Piolantron type, isopiolantron type, pyrantron type, perylene type and pyrene type polycyclic dyes represented by the following structural formulas, (In the formula, R represents an alkyl group or an aryl group, and n represents a positive number of 0 to 8.) and the like.

Among these, benzopyran-based and perylene-based fluorescent colorants can be particularly preferably used because of their excellent light resistance.

These ultraviolet absorbers and fluorescent colorants can be used alone or in combination of two or more.

The amount of the ultraviolet absorber and the fluorescent colorant added should be adjusted according to the thickness of the film or sheet. For example, in the case of about 100 μm, the ultraviolet absorber is 0.5 to 2% by weight with respect to the thermoplastic resin, The preferable range of the colorant is 0.01 to 1% by weight.

If the amount of the ultraviolet absorber is less than 0.5% by weight, the effect of controlling pests is weakened, and if the amount is more than 2% by weight, there is a problem that the additive causes the film to bleed on the surface, which is not preferable. On the other hand, when the amount of the fluorescent coloring agent is less than 0.01% by weight, the color of fruits and flowers is difficult to be expressed, and when it is more than 1% by weight, the light transmittance in the visible light range is lowered and the growth of the crop is adversely affected. It is not preferable because

Then, the film or sheet of the present invention can be obtained by a usual film or sheet processing method, which is a thermoplastic resin in which a thermoplastic resin is mixed with an ultraviolet absorber and a fluorescent colorant.

For example, a thermoplastic resin composition containing an ultraviolet absorber and a fluorescent colorant, a conventional Banbury mixer or a two-roll kneader or extruder, by mixing and kneading the additives while melting the resin can get. The obtained resin composition can be formed into a film or a sheet by a usual film or sheet processing machine such as inflation film processing, T-die film or sheet processing, or calendar processing.

It should be noted that the purpose is to increase the heat retention at night in the covered house, that is, the heat absorbed into the ground inside the house by daytime sunlight is radiated from the ground at night, but to prevent the transmission of this radiation. , Silicon oxide, aluminum silicate, aluminosilicate, inorganic infrared absorbers such as phosphate compounds in these films, and organic high-infrared absorbing resin compounds such as ethylene-vinyl acetate saponification products and polyacetal resins Etc. can be blended.

<Effects of the Invention> The film or sheet obtained as described above can be used for coating houses and tunnels, and can control pests and disease fungi of crops by applying selective light rays to the crops, and Promotes anthocyanin synthesis such as eggplant skin color and flowers.

<Examples> Next, the present invention will be described with reference to Examples, but these Examples are merely illustrative, and the present invention is not limited thereto.

The performance tests of the films and sheets shown in Examples and Comparative Examples were carried out by the following method.

(1) Sunlight Transmission Spectrum A solar radiation (1100 nm to 200 nm region) transmission spectrum of the film or sheet was measured using a spectroradiometer (OSMO-601 type) manufactured by Optical Science.

(2) Pest control effect and eggplant peel color Eggplants are cultivated under the film coating of Examples 1 to 10 and Comparative Examples 1 to 4 to remove the green peach aphid (winged insect) and Southern yellow azium (adult and larva). Number of flying heads (eggplant 40
(In the leaf).

In addition, the Lab value of the peel is measured with a spectrophotometer (MPS-2000) manufactured by Shimadzu Corporation, in contrast to the eggplant cultivated without coating,
The color difference (ΔE) from the Lab value of the peel of the eggplant cultivated under the uncoated condition was calculated. The smaller the color difference (ΔE), the smaller the difference in the peel color of eggplant from the cultivation under the uncoated condition, and the better.

Example 1 Low density polyethylene (M1 = 1.5 g / 10 min, density = 0.922 g / cm)
^In ( ³ ), 0.8% by weight of 2- (2'-hydroxy-5'-methylphenyl) -5-chlorobenzotriazole, and a perylene dye (trade name: Fluorescent Red-300 manufactured by BASF).
A mixture of 02% by weight was mixed and the resulting mixture was molded into a single-layer film having a thickness of 100 μm using an isoflation film processor.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 2 A low-density polyethylene of Example 1 was replaced by an ethylene-vinyl acetate copolymer (MI = 1.5 g / 10 minutes, vinyl acetate content 15% by weight), and the same procedure as in Example 1 was performed to obtain a thickness of 100 μm.
Was formed into a single layer film.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 3 In Example 1, aluminum silicate (Al ₂ O ₃ 27.5% by weight, SiO ₂ 72% by weight,
A single-layer film having a thickness of 100 μm was formed in the same manner as in Example 1 except that 0.5% by weight of impurities and 5% by weight of average particle size of 4.5 μm were added.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 4 The aluminum silicate used in Example 3 was
Aluminosilicate gel (23% by weight of Al ₂ O ₃ , 61% by weight of SiO _2, 10% by weight of Na ₂ O, previously dried at 250 ° C. for 2 hours,
A single-layer film having a thickness of 100 μm was formed in the same manner as in Example 3 except that the loss on ignition was changed to 6% by weight and the average particle size was changed to 8% by weight.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 5 Ethylene-vinyl acetate copolymer (MI = 1.5 g / 10 minutes, VA content 15% by weight), silicon oxide (SiO ₂ 99% by weight or more, average particle size 2 μm) 5% by weight, 2-hydroxy- 0.5% by weight of 4-methoxybenzophenone and 0.04% by weight of a benzopyran dye (trade name: Fluorol Red BK manufactured by BASF) were kneaded, and the resulting mixture was used as an intermediate layer to prepare an ethylene-vinyl acetate copolymer (MI = 1.5 g / 10 Min., Vinyl acetate content 10% by weight), a mixture of 0.5% by weight of 2-hydroxy-4methoxybenzophenone and 0.04% by weight of benzopyran dye is used for laminating both inner and outer layers using a three-layer blown film processing machine. A two-kind three-layer film was processed at 180 ° C. to form a film having an inner / outer layer / intermediate layer thickness composition ratio of 4/6 and a thickness of 100 μm.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 6 Ethylene-methyl-methacrylate-vinyl acetate copolymer (MI = 1.5 g / 10 minutes, vinyl acetate content 13% by weight, methylmethacrylate content 3% by weight) was previously added to 250 ° C.
Zeolite dried for 2 hours (Grace's trade name SYLO
SIV100, average particle size 2.5 μm) 8% by weight, 2-hydroxy-4methoxybenzophenone 0.5% by weight, perylene dye (BASF's trade name Fluorscent Red 300) 0.02% by weight
Was kneaded, and the resulting mixture was used as an intermediate layer in low-density polyethylene (MI = 1.5 g / 10 min, density = 0.922 g / cm ³ ) with 0.5% by weight of 2-hydroxy-4methoxybenzophenone and 0.02% of perylene dye. A film having a thickness of 100 μm was formed by performing film processing in the same manner as in Example 5 so that the mixture in which the weight% was mixed can be laminated on both the inner and outer layers.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 7 Same as Example 6 except that the 2-hydroxy-4methoxybenzophenone used in Example 6 was changed to 0.8% by weight of 2- (2'-hydroxy-5'-methylphenyl) -5-chlorobenzotriazole. Was formed into a film having a thickness of 100 μm.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 8 In Example 6, 2-hydroxy-4methoxybenzophenone was replaced with 0.8% by weight of 2- (2'-hydroxy-5'-methylphenyl) -5-chlorobenzotriazole, and the addition amount of the perylene dye was 0.04% by weight. A film having a thickness of 100 μm was formed in the same manner as in Example 6 except that the percentage was changed.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 9 100 parts by weight of polyvinyl chloride, 50 parts by weight of dioctyl phthalate, 1.5 parts by weight of dibutyltin maleate, 1.0 part by weight of zinc stearate, 0.2 part by weight of stearic acid, 1.5 parts by weight of sorbitan sesquipalmitate were mixed, and further 2- 0.5% by weight of hydroxy-4 methoxybenzophenone and benzopyran dye (trade name Fluorol Red manufactured by BASF)
BK) 0.04% by weight was added, and the mixture was sheeted with a calender roll at 160 ° C. to form a film having a thickness of 100 μm.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Example 10 Poly (methyl methacrylate) (trade name Sumipex B MHG manufactured by Sumitomo Chemical Co., Ltd.) was added to 2- (2′-hydroxy-5 ′).
-Methylphenyl) -5-chlorobenzotriazole 0.
8% by weight, perylene dye (trade name Fluorescent manufactured by BASF)
Red300) 0.02 wt% was added and mixed with a super mixer, and a 1 mm sheet was obtained by an extruder under the condition of a resin temperature of 240 ° C.

The performance and test results of the obtained sheet are shown in FIG. 1 and Table 1.

Comparative Example 1 A film having a thickness of 100 μm was formed in the same manner as in Example 6 except that 2-hydroxy-4methoxybenzophenone and the perylene dye were removed from Example 6.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Comparative Example 2 The thickness was the same as in Example 6 except that 2-hydroxy-4methoxybenzophenone was removed from Example 6.
A 100 μm film was molded.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

Comparative Example 3 A film having a thickness of 100 μm was formed in the same manner as in Example 6 except that the perylene dye was removed.

Comparative Example 4 In Example 6, 0.8% by weight of 2-hydroxy-4methoxybenzophenone was added to 2- (2′-hydroxy-5′-methylphenyl) -5-chlorobenzotriazole.
Instead, a 100 μm thick film was formed in the same manner as in Example 6 except that the perylene dye was removed.

The performance and test results of the obtained film are shown in FIG. 1 and Table 1.

[Brief description of drawings]

FIG. 1-a to FIG. 1-n show solar radiation transmission spectrum diagrams under the film or sheet coating obtained by Examples and Comparative Examples of the agricultural film or sheet according to the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Nakatsuji 2-10-1 Tsukahara, Takatsuki-shi, Osaka Sumitomo Chemical Co., Ltd. (56) Reference JP-A-60-149322 (JP, A)

Claims (1)

[Claims] 1. Of the spectral transmission energy under natural light, ultraviolet rays having a wavelength of 380 nm or less are substantially non-transmissive,
Without blocking the transmission of visible light of wavelength 400 ~ 500 nm,
And it absorbs visible light of wavelength 510 ~ 600 nm,
A red-colored agricultural film or sheet which amplifies transmission of visible light of 00 nm and has a ratio of an average transmittance of 400 to 500 nm to an average transmittance of 600 to 700 nm of less than 1. .