JPH04131018A - Vinyl chloride resin film for agriculture - Google Patents

Abstract

PURPOSE:To provide the subject film exhibiting a fog-generating phenomenon- inhibiting powder at places near to the inner surface of a covering material by compounding a vinyl chloride resin with an antifogging agent comprising a sorbitan surfactant, a fluorine-containing compound, and a specific benzotriazole derivative in a specific ratio. CONSTITUTION:The objective film comprises 100 pts. wt. of a vinyl chloride resin, 1.5-5 pts.wt. of an antifogging agent comprising a sorbitan surfactant (preferably sorbitan monopalmitate), 0.01-0.2 pt.wt. of a fluorine-containing compound and 1.0-5.0 pts.wt. of a chlorine group-containing o- hydroxybenzotriazole derivative [e.g. 2-(2'-hydroxy-5'-methylphenyl)-5,6- dichlorobenzotriazole].

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an agricultural vinyl chloride resin film. This invention relates to an agricultural vinyl chloride resin film that has an excellent ability to exhibit the following properties (referred to as fog-proofing properties) over a long period of time.

``Conventional technology'' In recent years, in order to increase the productivity and marketability of useful plants, they have been covered with agricultural covering materials such as agricultural vinyl film.
2. Description of the Related Art So-called greenhouse cultivation and tunnel cultivation, in which useful plants are cultivated under forced, semi-forced or suppressed conditions, are widely practiced. In greenhouse cultivation and tunnel cultivation, most of the vinyl chloride resin films currently used cover the inner surface of the covering material (the surface facing the inside of the greenhouse or tunnel).
In order to promote the flow of water droplets and increase the amount of sunlight incident, it contains an antifogging agent (mainly sorbitan fatty acid ester; glycerin fatty acid ester, etc.), which is a type of surfactant. When covered with a coating material containing such an antifogging agent, when the temperature difference between the inside and outside of the coating material becomes large, fog is generated near the inner surface of the coating material.
often observed.

This fog phenomenon often occurs in late autumn or winter, which is the most important period for greenhouse cultivation, tunnel cultivation, and other facility cultivation. The causes of fog generation phenomenon are not precisely known, but include the temperature and humidity inside the greenhouse or tunnel, the temperature and moisture content of the soil inside the greenhouse or tunnel, the amount of solar radiation to the greenhouse or tunnel, and the wet surface of the covering material. Due to subtle effects such as the degree of hydrophilicity, moisture inside the house or tunnel adheres smoothly to the surface of the sheathing material due to temperature changes, and some moisture does not flow, forming a mist near the inner surface of the sheathing material. It is presumed that this is due to the

According to the observations of the present inventors, such a fog generation phenomenon is caused by
It has been found that this occurs near the ground surface in greenhouses or tunnels, near cultivated plants, and near the inner surface of covering materials. Furthermore, the cladding material and the inner surface of the cladding material are cooled by the drop in outside temperature, creating a temperature difference between them and the inside of the house, and when the warm, humid air inside the house moves to the vicinity of the inner surface of the cladding material due to natural convection. It has been found that water vapor that can no longer be contained in the air condenses into minute water droplets, which become mist and spread inside the house or tunnel by natural convection. - If the mist-like minute water droplets that have been generated once again evaporate and disappear during natural convection, the fog will not spread into the house or tunnel, but if the rate of evaporation and disappearance is slow, the fog will not spread into the house or tunnel. It was also found that the entire area was covered in thick fog.

Such fogging phenomenon wets the leaves, stems, flowers, fruits, etc. of useful crops grown in greenhouses or tunnels, causing the occurrence of diseases or even aiding the spread of diseases. Also, if the cultivated crops become wet, the heat required to dry them is disadvantageous, such as the need for more fuel for heating the greenhouse or tunnel. moreover,
There are also negative effects such as a decline in the efficiency of agricultural work due to poor visibility within the area.

To overcome these disadvantages, conventional methods have been to use colored synthetic agricultural resin films or cover the soil inside greenhouses or tunnels with mulching films in order to soften temperature changes inside greenhouses or tunnels. To reduce the amount of water evaporation, improve the irrigation time (for example, watering later in the evening, adjust the area and amount of water to be watered, etc.), improve the irrigation method and equipment, etc. measures have been taken. However, none of these methods was effective in completely suppressing the fog generation phenomenon.

As a technique to improve such drawbacks, Japanese Patent Application Laid-Open No. 57-1
As described in Japanese Patent No. 4648, a method has been proposed in which a surfactant as an antifogging agent and a fluorine-containing surfactant for improving antifogging properties are used in combination. Also, JP-A-59-
Japanese Patent Application No. 80468 also proposes a method of improving fog resistance by blending a copolymerized oligomer of an acrylate or methacrylate containing a terminal polyfluoroalkyl group with another copolymerizable compound.

``Problems to be Solved by the Invention'' However, according to experiments conducted by the present inventors, when an antifogging agent is further combined with a fluorosurfactant or a copolymerized oligomer, agricultural vinyl chloride resin coating It may have a negative effect on the anti-fog property, which is an essential performance for the material, and the anti-fog property will not deteriorate much even if used in the low temperature winter, but if you start using it in the high temperature summer or early autumn. It has been found that the deterioration of anti-fogging properties is accelerated and the durability of anti-fogging may be markedly inferior. Although it is possible to reduce the negative effect on antifogging properties by reducing the amount of fluorosurfactants, etc., the fog prevention effect is not satisfactory, especially when used for a long period of time. Significant decline in sex.

"Means for Solving the Problem" Under such circumstances, the present inventors have developed an agricultural vinyl chloride resin coating material that does not reduce the anti-fog durability and exhibits anti-fog properties for a long period of time. As a result of intensive studies, we found that even when a small amount of fluorine-based surfactant is added, by combining a benzotriazole derivative with a chlorine group, fog prevention can be achieved without impairing anti-fog properties. It was discovered that this material exhibits its properties over a long period of time, and this led to the completion of the present invention.

The gist of the present invention is to use 1.5 to 5 parts by weight of an antifog agent made of a sorbitan surfactant and 0.0 parts by weight of a fluorine-containing compound per 100 parts by weight of a vinyl chloride resin.
01 to 0.5 parts by weight, and 1.0 to 0.5 parts by weight of 0-hydroxyphenylhensito IJ7duyl derivative having a chlorine group.
There is an agricultural vinyl chloride resin film containing 5.0 parts by weight.

The present invention will be explained in detail below.

In the present invention, the vinyl chloride resin refers to polyvinyl chloride, a copolymer mainly composed of vinyl chloride with other comonomers, a mixture thereof, or a mixture of these with other polymers or copolymers.

As the sorbitan surfactant used as an antifogging agent in the present invention, sorbitan monopalmitate, sorbitan monostearate, or alkylene oxide adducts thereof are preferable.

The amount of antifogging agent added to the base resin can be the same as that used for conventional agricultural vinyl chloride resin films, and is 1. It can range from 5 to 5 parts by weight.

In the present invention, the fluorine-containing compound may be a conventionally used fluorine-based surfactant or
Copolymerized oligomers of unsaturated esters containing 20 polyfluoroalkyl groups with other copolymerizable compounds can be used.

Examples of the fluorine-based surfactant include compounds represented by Hani.

RfCONH(CJ,0)nH RfCON(Cz41tO)nR RfCON(CzHaO)nl( (Cu2O)nR RfCON(CJnO)nR (CJaO)nR RfSOzNII(C21'1.O) nRRfSO,
N(Cu2O)nll RfSOzN(CJ,0)nR RfSOzN(CzH,0)nH (CJsO)nR RfSOzN(C,H,0)nR (CzHnO)nR RfCHzCHCHtO(Cu2O)nRH Next - RFC) 12ci(2SC H2CHCH20( Cu2O
)r+RH RfSO□17(J12CH,0H CI(,CH,01( 1?fS02NCH2CH(01()C3H70COC
H(OH)CI(20)1 (wherein Rf represents a linear or branched polyfluoroalkyl group, R represents an alkyl group, and n represents a natural number.

) The polyfluoroalkyl group contained in the fluorine-containing compound used in the present invention preferably has 6 to 12 carbon atoms.

Examples of copolymerized oligomers include the following.

Copolymerized oligomer (1) CFs(CFz), 5OJ(C)li) (CL)A0COC(CHt) = CL and CHsOCOCH=C
Hz and lo(CHCHO)sOcOcH=cHz Copolymerized oligomer (2) CFj (Ch) 6 (CH ri 20COC(CL)
= CH2 and CzHsOCOCH= C1 (with z)
10(CHCHO)20COCH=C11, copolymerized oligomer (3
) CF3 (CFz) ficONH (CHI) 20C
OC(C)13) = CHz and CH5OcOcH=
CHt and HO (CHCHO) + oOcOcH=
Copolymerized oligomer (4) CF x (CF t) @ (CHz) zOcOcH with a molecular weight of 2000, which was polymerized with CHt at a charge weight ratio of 1:1.
= COz and C3H70COCH-CI (! and) 1
Copolymerized oligomer (5) CPsCF(CFi)6C)lzcH(OH)CHzO, which was polymerized with 0(CHCHO)+0COCH=CJ at a charge weight ratio of 1:0.1:1.
COC)l=cHz and CF3 CzHsOCOCH= CHz)to(CHCHO)
30COCII=CII2, preparation weight ratio 1:0
．． The fluorine-containing compound used in the present invention is a copolymerized oligomer having a molecular weight of 6000 and polymerized at a ratio of
Each can be used alone, or two or more types can be used in combination.

The amount of this fluorine-containing compound added to the vinyl chloride resin coating material can be changed depending on the type of fluorine-containing compound to be blended, the type of the base vinyl chloride resin, etc. (However, plasticizer is not included in the calculation. The same applies hereinafter) 0.01 part by weight or more, 0.
5 parts by weight or less is sufficient, and the preferred range of blending amount is 0.5 parts by weight or less.
02 to 0.2 parts by weight.

Further, in the present invention, as the 0-hydroxyphenylhencytriazole derivative having a chlorine group, specifically, a compound represented by the following general formula (1) is preferable.

(In the formula, R' and R2 are a hydrogen atom or a carbon atom number of 1
~8 linear or branched alkyl groups or chlorine atoms, and Yl and Yl represent hydrogen atoms or chlorine atoms. ) More specifically, for example, 2-(2'-hydroxy-5
゛-methylphenyl)-5,6-cyclohenzotriazole, 2-(2'-hydroxy-5゛-tbutylphenyl)-5-chlorohenzo) IJ azole, 2-(
2"-hydroxy-3'5"-butylphenyl)
-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-1-butyl-5methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3
”, 5°-dichlorophenyl)hencytriazole, 2
-(2''-hydroxy-4',5'-dichlorophenyl)benzotriazole and the like.

The amount of these benzotriazole derivatives added to the base resin can be in the range of 0 to 5.0 parts by weight.

The vinyl chloride resin base material constituting the agricultural vinyl chloride resin film according to the present invention may contain various usual resin additives, such as plasticizers, lubricants, heat stabilizers, light stabilizers, Antioxidants, colorants, etc. can be included in conventional amounts.

Suitable plasticizers that can be used include, for example, phthalic acid derivatives such as di-n-octyl phthalate, di-2-ethylhexyl phthalate, dibenzyl phthalate, diisodecyl phthalate, didodecyl phthalate, and diisodecyl phthalate; Isophthalic acid derivatives; Adipic acid derivatives such as di-n-butyl adipate and dioctyl adipate; Maleic acid derivatives such as di-n-butyl maleate; Citric acid derivatives such as trilobyl citrate; Itaconic acid derivatives such as monobutyl itaconate Oleic acid derivatives such as butyl oleate; Ricinoleic acid derivatives such as glycerin monolysyllate; Other examples include tricresyl phosphate, epoxidized soybean oil, and epoxy resin plasticizers.

Examples of the lubricant or heat stabilizer include polyethylene wax, liquid paraffin, methylenebishigher fatty acid amide, stearic acid, zinc stearate, fatty alcohol, calcium stearate, barium stearate, barium ricinoleate, diptyltin dilaurate, and diptyltin. Examples include simalate, organic phosphate metal salts, organic phosphite compounds, phenols, and β-diketone compounds.

As the light stabilizer, various compounds that are commonly added to agricultural vinyl chloride films can be used. Specifically, for example, 4-acetoxy-2゜2.6.6-titramethylpiveridine, bis(2,2,6,6-tetramethyl-4-piperidyl)adipate, tris(2,2,6
,6-tetramethyl-4-piperidyl)benzene-1,
3,5-tricarboxylate, tetrakis(2,2,
6,6-tetramethyl-4-piperidyl)propane-1
, 1,2,3-tetracarboxylate and other hindered amine compounds.

As an antioxidant, 2,6-tert-butyl-
4-methylphenol, 22゛-methylenebis(6-t
ert-butyl-4-ethylphenol), dilaurylthiodipropionate, and the like.

Examples of colorants include phthalocyanine blue, phthalocyanine green, Hansa yellow, alizarin lake,
Examples include titanium oxide, zinc white, ultramarine blue, permanent red, quinacridone, and carbon black.

These resin additives may be contained in a small amount of 10 parts by weight or less per 100 parts by weight of the vinyl chloride resin base material.

In order to blend an antifogging agent, a fluorine-containing compound, a hensitriazole derivative, and various resin additives, if necessary, into the vinyl chloride resin that serves as the base material, conventional blending techniques and mixing techniques such as a ribbon blender, a Banbury mixer, and a supermarket are used. Can be mixed by mixer or other blender mixer. In order to form a film from a vinyl chloride resin, a method known per se, such as a melt extrusion method, a solution casting method, a calender method, etc., may be employed.

If the thickness of the agricultural vinyl chloride resin film according to the present invention is too thin, the strength will be insufficient, which is undesirable.On the other hand, if it is too thick, it will be difficult to make the film into a film, and the subsequent handling (cutting the film and joining it into a house shape) is not desirable. 0.03 to 0.2 as it causes inconvenience to the work (including the work of expanding the greenhouse), etc.
It is preferable to set it in the range of mm.

Moreover, the agricultural vinyl chloride resin film according to the present invention is
Similar to conventionally used agricultural covering materials, it can be spread over agricultural and horticultural facilities such as greenhouses and tunnels, and used for cultivating useful plants.

"Effects of the Invention" The agricultural vinyl chloride resin film according to the present invention has the following particularly remarkable effects, and its industrial utility value is extremely large.

(1) In the greenhouse or tunnel in which the agricultural vinyl chloride resin film according to the present invention is spread, fog generation near the inner surface of the film is effectively suppressed, as is clear from the examples below, and it can be used for a long period of time. However, there is little decrease in fog-proofing properties, and its suppressive effect is extremely strong.Even in late autumn and winter, when fog has traditionally been said to occur frequently, fog generation can be virtually completely suppressed, making it possible to suppress the occurrence of fog. It has a remarkable effect on preventing disease outbreak and spread. Therefore,
There is no need to pay close attention to irrigation, etc. as in the past.

(2) The agricultural vinyl chloride resin film according to the present invention not only has an effect of suppressing fog generation, but also has excellent antifogging properties and antifogging durability, and is useful for the facility cultivation of useful plants.

Hereinafter, the present invention will be explained in detail based on examples.
The present invention is not limited to the following examples unless it exceeds the gist thereof.

Examples 1 to 3, Comparative Examples 1 to 3 Polyvinyl chloride (degree of polymerization = 1300) 100 parts by weight Dioctyl phthalate 45 Tricresyl phosphate 5 Epoxy resin 2Ba-Zn liquid stabilizer
2Ba-Zn powder stabilizer
1 was used as the basic composition, and the antifogging agent shown in Table 1, a fluorine-containing compound, and an 0-hydroxyphenylbenzotriazole derivative having a chlorine group were blended therein and mixed in a super mixer. The mixture was fed to a calender molding machine heated to 180°C, and formed into a film by a conventional method to a thickness of 0.
Six types of 1 ran films were created.

A fog generation test and an antifogging property evaluation were performed on the above six types of films using the following methods.

The results are shown in Tables 2 and 3.

(1) Fog generation test: Six pipe houses with a width of 5.4 m, a ridge height of 3 m, and a depth of 15 m were constructed in a field in Shigeken-Shigun, and each building was coated with one of the above films. The degree of fog generation was evaluated for 5 days (October 30 to November 3, 1989) one month after covering the pipe house with the film, and for 5 days four months after the film was covered (1990). (January 29th to February 2nd) and for five days six months after coating (March 26th to March 1990).
I went there on the 30th of the month.

The numerical values of "fog generation evaluation" have the following meanings.

“1”: No fog is observed inside the house, or a slight amount of fog is generated only near the inner surface of the film.

"2" ...There is fog throughout the house, but 15
Condition in which the back of the house m ahead can be clearly identified.

``3'' ... A slightly thick fog has formed throughout the house, and 15
A state where it is not possible to clearly identify the back of the house m ahead.

``4'': The entire house was covered in fog, making it impossible to discern the back of the house from 15 meters away.

The second value is the average of the values for the five days during which the fog formation situation was observed.
Shown in the table.

(2) Evaluation of anti-fog properties A field in Nagoya City, Aichi Prefecture with a width of 2 m, a height of 2 m, and a depth of 3
The six types of films mentioned above were coated on a single-roof type house with a height of 0 m on September 22, 1989, and on another house of the same type on October 27, 1989, and the anti-fogging properties of each film were observed with the naked eye. ,
evaluated. The results are shown in Table 3.

The numerical values of "antifogging performance evaluation" have the following meanings.

“1”: Water adheres in a thin film and no water droplets are observed.

"2": Water is attached in a thin film, but slightly large water droplets are observed.

"3": A state in which small water droplets are observed to be partially attached.

"4": A state in which fine water droplets are observed on the entire inner surface of the film.

\ ゛＼ No. table \

Claims (1)

[Claims] (1) Per 100 parts by weight of vinyl chloride resin, 1.5 to 5 parts by weight of an antifogging agent consisting of a sorbitan surfactant, 0.01 to 0.5 parts by weight of a fluorine-containing compound, and chlorine groups. An agricultural vinyl chloride resin film containing 1.0 to 5.0 parts by weight of o-hydroxyphenylbenzotriazole derivatives.