JPS58138745A - Vinyl chloride resin film for agricultural purpose - Google Patents

Abstract

PURPOSE:A film that is obtained by adding inert solid fine particles with absorption in infrared region of a specific wavelength and a metal salt of phosphoric or phosphorous acid to a vinyl chloride resin containing a plasticizer, thus showing good heat insulation and high resistance to weather. CONSTITUTION:(A) A vinyl chloride resin composition containing a plasticizer is combined with (B) inert solid fine particles with an absorption in the infrared region of 3-16 micron wave length, (C) inert solid fine particles with an adsorption in the infrared region of 16-40 micron wave length and (D) at least one selected wave length from metal salts of phosphoric acid or phosphorous acid with an absorption in a range from 3-40 microns. At least one selected from magnesium carbonate, magnesium silicate and magnesium oxide, as component B and at least one selected from magnesium hydroxide and aluminum hydroxide as component C are combined for use.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an agricultural vinyl chloride resin film, and more specifically, to an agricultural vinyl chloride resin film that has high heat retention and excellent weather resistance. .

In recent years, farmers cultivating useful plants have widely adopted methods of promoting or suppressing cultivation using greenhouses or tunnels for the purpose of improving profitability.

Materials for covering such houses or tunnels include:
Polyethylene film, ethylene-vinyl acetate copolymer film, vinyl chloride resin film, polyethylene terephthalate film, polycarbonate film, etc. are used. Among them, vinyl chloride resin film has better weather resistance, transparency, and
It is used the most because it is excellent in terms of heat retention, strength, cost, etc.

In order for an agricultural synthetic resin film to exhibit excellent heat retention properties, (a) sunlight should be able to pass through the greenhouse or tunnel as much as possible during the day when sunlight is irradiating it; (
b) Minimize the release of the heat accumulated in the soil heated by the sun's rays. It is necessary to have two properties:

A film made of vinyl chloride resin has better heat retention than a polyethylene film or an ethylene-vinyl acetate copolymer film. This is because the vinyl chloride resin film is highly transparent, so sunlight reaches the inside of the house or tunnel and warms the soil.This warmed soil warms the air, and the air flows inside the house or tunnel. It causes natural convection and warms the entire air inside the house or tunnel.
vInfrared region 0''10''-line The infrared spectra of 1 fat film and the radiation energy distribution of /3''Oj blackbody are shown.In Figure 1, curve 1 is agricultural polyvinyl chloride film; is an agricultural polyethylene film, curve 3 is an infrared spectrum line of an agricultural ethylene-vinyl acetate copolymer film, and curve DA is the radiant energy distribution of a 13°C blackbody ()-us or radiation from the ground inside the tunnel. (corresponds to energy distribution).

From Figure 1, agricultural polyvinyl chloride film has a deeper absorption of light at wavelengths in the infrared region than the other two types of films, and in particular, the wavelength at which the radiant energy from the ground reaches its maximum value is around 10 microns. It can be seen that it exhibits particularly deep absorption in the wavelength range of . It is thought that absorption in this wavelength region is related to the four-temperature property of the film.

By the way, in order to find out how much radiant energy from the ground is transmitted by a covering material such as a tunnel or tunnel, calculate the transmittance of the film itself and the radiant energy from the ground for each wavelength in the infrared region. The product may be integrated over the desired wavelength range. When the transmitted energy is calculated for the above three types of commercially available agricultural films (all having a thickness of 0.03 m), the values shown in Table 1 are obtained.

Table 1 Table 1 shows that polyvinyl chloride film has less transmitted energy than polyethylene film and ethylene-vinyl acetate copolymer film.

Furthermore, in the case of polyvinyl chloride film, the transmission energy is in the range of 3 to 16 microns per wavelength, and the wavelength range is 16 to 4! (The value is almost the same as that in the 11 micron range, so in order to further improve the heat retention of this film, the transmitted energy in both wave regions should be
It turns out that it is better to reduce them at the same time.

As described above, methods for reducing transmitted energy in a specific wavelength range include Japanese Patent Publication No. 60 of the Japanese Patent Publication Guartaco No. 60, Japanese Patent Publication No. 4I of the Japanese Patent Publication No. 4I? -/, 3gA3 Publication, JP-A-5S-
y, ytis, etc. have been proposed.

In all of these, inert solid fine particles having an ability to absorb in the infrared region are added to a synthetic resin as a base material, and then formed into a film.

However, it has been found that these conventional techniques have the following problems.

(1) Forming a film by blending silicon oxide, magnesium silicate, etc. that absorb in the infrared region with a synthetic resin raw material,
The coating material comes off from this film, making it unsuitable for long-term use.

(2) Even if commonly used ultraviolet absorbers, light stabilizers, etc. are added for the purpose of improving this weather resistance, the decline in weather resistance of the film caused by the addition of inert solid particles cannot be suppressed. However, it is difficult to maintain weather resistance at a certain level over long periods of time.

(3) The decrease in weather resistance of the film is proportional to the amount of inert solid particles added, and the heat retention of the film is
The relationship is such that the more the weather resistance is improved, the lower the weather resistance is.

Under such circumstances, the present inventors have discovered that agricultural vinyl chloride, which has high heat retention and excellent weather resistance, has been developed. The resin composition contains (A) one or more types of inert solid fine particles that have an absorption in the infrared region of wavelengths from 3 to 16 microns, and (B) inert particles that have an absorption of 1° in the infrared region of wavelengths from 16 to 410 microns. one or more types of active solid fine particles;
:(0) A film with excellent heat retention, characterized by being formed into a film containing at least one of metal phosphates and metal phosphites that absorb in the infrared region of wavelengths 3 to 5 microns. Found in agricultural vinyl chloride resin films.

The present invention will be explained in detail below.

In the present invention, the vinyl chloride resin refers to ``in addition to polyvinyl chloride, a copolymer containing vinyl chloride as a main component and a monomer copolymerizable with it, and a copolymer containing vinyl chloride as a main component and other monomers that are copolymerizable with it. This meaning includes blends with polymers and copolymers of

The film according to the present invention is formed from a flexible blended vinyl chloride resin composition. In order to obtain a soft blend, 30 to 60 parts by weight of a plasticizer is blended to 100 parts by weight of the vinyl chloride resin.

Preferred plasticizers in the present invention include, for example, di-n
- Hepthalic acid derivatives such as octyl phthalate, dicoethylhexyl phthalate, dibenzyl phthalate, diisodecyl phthalate, didodecyl phthalate, diisodecyl phthalate; isophthalic acid derivatives such as diisooctyl phthalate; adipine such as di-n-butyl adipate, dioctyl adipate, etc. Acid derivatives Maleic acid derivatives such as nitri-n-butyl maleate; citric acid derivatives such as nitri-n-butyl citrate; itaconic acid derivatives such as monobutyl itaconate; oleic acid derivatives such as butyl oleate; ricinol such as glycerin monolysyllate. Acid derivatives; other examples include tricresyl phosphate, epoxidized soybean oil, and epoxy resin plasticizers.

The film according to the present invention contains (A) one or more kinds of inert solid fine particles having absorption in the infrared region of wavelengths 3 to 6 microns, and CB) wavelengths of 16 to q.

One or more types of inert solid fine particles that absorb in the infrared region of microns, and (O) at least one of metal phosphates and metal phosphites that absorb in the infrared region of wavelengths 3 to aO microns. are combined and mixed respectively.

The inert solid fine particles of component (A) that absorb in the infrared region of wavelengths of 3 to 16 microns function to reduce the transmitted energy of light rays in the infrared region of wavelengths of 3 to 16 microns of the film according to the present invention. be.

Preferably used components include magnesium carbonate, magnesium silicate, silicon oxide, aluminum oxide, barium sulfate, calcium sulfate, and the like. These may be used alone or in combination of two or more. Among the examples, magnesium carbonate, magnesium silicate and silicon oxide are particularly preferred.

If the amount of the above component (g) is too small, no improvement in heat retention can be expected; on the other hand, if too much mulberry is added, the weather resistance of the film cannot be maintained at a desirable level, and the film's mechanical This is not preferable because it also reduces the optical properties and transparency of the film. The suitable range for blending is
The range is 5' parts by weight (total of components ~ and component (b) below) based on ioo parts by weight of the vinyl chloride resin.

The wavelength of the elongated component is 16 to 0 microns, and the wavelength of the film is 16 to 4! . It functions to reduce the transmitted energy of light in the micron infrared region.

(Things that can be used as the I9 component include magnesium hydroxide, aluminum hydroxide, calcium hydroxide, etc.)
These may be used alone or in combination of two or more.

If the amount of the component (B) is too small, no improvement in heat retention can be expected, and on the other hand, if it is too large, the track resistance of the film cannot be maintained at a desirable level.
This is not preferable because it also reduces the mechanical properties of the film, the transparency of the film, etc. The preferred blending amount range is the (middle) component and the above (()) per 100 parts by weight of the vinyl chloride resin.
The total amount of component A) is /-/j parts by weight.

(0) Component wavelength 3-tio micron infrared region
Metal phosphates and metal phosphites with absorption in 1 are:
It functions to improve the weather resistance of the film containing the components (a) and (b) above, and to reduce the transmitted energy of light in the wavelength range of 3 to 41 □ microns.

The (') component has the general formula MIH, PO,, M! II
HPO,,M'H,FO,,MJllPOa,"H"
It is a compound represented by ``a s''(''*''a)* (in the formula, M means a metal component, 〇 means monovalent, ■ means divalent), etc., and the M component includes barium, calcium, etc. , zinc, lead, aluminum, nickel, etc. are suitable.

These (0) components may be used alone or in combination of two or more.

The blending amount of component (0) is unfavorable because if there is too little residue, the weather resistance of the film cannot be improved to a desirable level, whereas if there is too much residue, there will be a lot of spraying out from the film and the transparency will be reduced. In addition to this, it also causes a lot of dust to adhere, which is not desirable. The suitable range of blending amount is (A)
It is preferable to set it in the range of 0.0/-/ with respect to the total weight of the component and (B) component (12i)%f = Q-'""
'o).

The film according to the present invention contains the above-mentioned components (A) to (0), and in addition, if necessary, a lubricant, a heat stabilizer, an antistatic agent, an antifogging agent, an ultraviolet absorber, a pigment, and a dye. Various resin additives such as these can be blended.

Examples of lubricants or heat stabilizers that can be incorporated into the film of the present invention include polyethylene wattles, liquid paraffin, stearic acid, zinc stearate, fatty alcohols, calcium stearate, barium stearate, barium ricinoleate, and dibutyltin. Laurate, dibutyltin malate, etc. cause irritation.

As the antistatic agent or antifogging agent that can be blended, nonionic surfactants are preferred, and specifically sorbitan surfactants such as sorbitan monostearate, sorbitan monopalmitate, and sorbitan monobenzoate; glycerin Glycerin-based surfactants such as monolaflate, diglycerin monopalmitate, and glycerin monostearate: Polyethylene glycol-based surfactants such as polyethylene glycol monostearate and polyethylene glycol monopalmitate: Fullylene oxide adducts of alkylphenols; Examples include esters of sorbitan/glycerin condensates and organic acids.

Examples of the ultraviolet absorber include phenyl salicylate-based, cyanoacrylate-based, benzoate-based, benzophenone-based, and benzotriazole-based ultraviolet absorbers. Examples of pigments and dyes include titanium oxide, silica, ultramarine blue, and phthalocyanine blue.

These various resin additives can be selected in the usual amount, for example, within the range of S parts by weight or less per ioo parts by weight of the vinyl chloride resin.

Component (A) or 0 is added to the base vinyl chloride resin.
) components and, if necessary, various resin additives, etc., are compounded using ordinary compounding techniques and mixing techniques, such as pump blenders, Bamba* mixers, super mixers, and other compounders and mixers. After mixing, it is possible to form a film.

In order to form a vinyl chloride resin composition into a film, methods known per se, such as melt extrusion, solution casting, and calendering, may be employed. The film may be transparent or may have many small irregularities (embossed) on its surface.

If the thickness of the film according to the present invention is too thin, the strength will be insufficient, which is undesirable.On the other hand, if the film is too thick, it will be difficult to form the film, and the subsequent handling (cutting the film and joining it into a house shape) will be difficult. (including the work of spreading it onto the house frame), etc., so it is preferable to set it in the range of 0.03 to 0.2.

The film according to the present invention has the following effects:
. Agricultural L015 value level N6, Ruo,
1) The film according to the present invention contains inert solid fine particles that absorb heat rays, so it can absorb wavelengths of 3 to 4 I emitted from soil.
It does not emit light (heat rays) in the infrared region in the θ micron range outside the house or tunnel, and has excellent heat retention.

■ As inert solid particles that absorb heat rays, components (A) and (B) with different absorption wavelength ranges are used together, so the transmitted energy can be reduced over the entire range of infrared rays with wavelengths of 3 to 4 microns. I can do it. The amount of inert solid fine particles to be blended can be smaller than that in the conventional case where a single compound is used alone.

■ Since the film according to the present invention contains component (C) in addition to component (A) and CB), it is significantly more effective than conventional films that contain only inert solid particles that absorb heat rays. Shows excellent weather resistance.

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

Example 1-da, Comparative Examples 1-9 Polyvinyl chloride (〒=/4I00) 10
0 parts by weight Dioctyl 7 Talley)
so tt tricresyl phosphate
5 parts by weight epoxy resin (product name: 1liP
-821'') / #Barium-zinc liquid stabilizer /J #Barium stearate O, CO I Zinc stearate 0.4I #Sorbitan monopalmitate gradient is the basic composition, and the types and types shown in Table 1 are added. Amounts of components (A), (B) and (0) were blended and mixed by stirring for 10 minutes using a super mixer. Each mixture was fed into a calender heated to tts°C and formed into films by a conventional method to produce 13 types of films with a thickness of 00OS.

The 13 types of films mentioned above were evaluated for weather resistance, heat retention, and jetting properties using the following methods. The evaluation results are shown in Table 2.

(1) The test film was made of weather-resistant Nagoya cloth from Aichi Prefecture, and was placed outdoors facing south.
And, it is extended on a pedestal tilted at 4IS degrees with respect to the ground.
After exposure to sunlight (September 1988), changes in the appearance of each film were observed and evaluated with the naked eye.

The evaluation results of "weather resistance" each have the following significance.

○・・・・・・No change 0×・・・・・・Slight brown spots are observed △
......Δ× where brown spots are observed...
...We constructed 13 open-air tunnel frames, each 2m wide and 2m long, in a field in Mie-Shigun, where many brown spots are observed, and covered each of these tunnels with a film. Measurement of the temperature inside the tunnel at night.

The temperature measurement period was 10 days from March 1st to March 10th, 1920.

The temperature was measured every hour from 6:00 pm to 6:00 am of the next day, and the temperature during this period was averaged to give the daily average value, and the daily average value for the 1 day was shown as the average value. .

(3) Ejection properties Each film was left in a room for 6 months, and the surface of the film was lightly touched with a fingertip, and judgment was made based on the mark left on the surface of the film.

The evaluation criteria were as follows: 0 0... Almost no finger marks were observed on the surface.

△・・・・・・Some finger marks are observed.

×・・・・・・Things that leave significant finger marks.

In the next table, the following becomes clear.

The film according to the present invention, which contains the three components (A) to 9, not only has excellent weather resistance but also excellent heat retention, and there is extremely little ejection of additives onto the film surface.

Even if the film contains three components, if the amounts of the three components are not balanced (Comparative Example 1, Comparative Example 6, and Comparative Example 7), the film will not have excellent both ltil properties and heat retention properties. However, if the film containing only the - component (Comparative Example 3, Comparative Example IO) and the film containing two components (Comparative Example: 1) are also excellent in both weather resistance and heat retention, it is a fortune-telling.

[Brief explanation of the drawing]

Figure 1 shows the currently commercially available thickness 0.0! ; Infrared spectra of agricultural synthetic resin film of H and 1! ”
(:) Shows the radiant energy distribution of a black body. In the figure, l is the infrared spectrum curve of agricultural polyvinyl chloride film, c is the infrared spectrum curve of agricultural polyethylene film, 3 is the agricultural ethylene-vinyl acetate copolymer cylinder curve, and da is black at 13°C. Each shows the radiant energy distribution of the body. Applicant Mitsubishi Monsanto Chemicals Co., Ltd. Agent Patent attorney Whether necessary - (1 other person) ■ I□

Claims (1)

[Scope of Claims] (1) A salt ear vinyl resin composition containing a plasticizer, and (A) one or more types of inert solid fine particles having absorption in the infrared wavelength range of 3 to 16 microns. , 0) one or more types of inert solid fine particles that absorb in the infrared region of wavelengths 16 to 1IO microns; (0) metal phosphates and phosphorous acid that absorb in the infrared region of wavelengths 3 to 4 IIO microns; Vinyl chloride resin film O for commercial use with excellent heat retention, characterized by being formed into a film by blending at least one of metal salts [2] Magnesium carbonate, magnesium silicate as component (A) and silicon oxide, and at least one of magnesium hydroxide and aluminum hydroxide as the middle component. Vinyl chloride resin film. (3) A patent characterized in that the metal component of the metal phosphate or metal phosphite as the component in (0) is selected from calcium, barium, zinc, lead, or aluminum. A vinyl chloride resin film for industrial use according to claim (1). (4) The blending amount of component (A) and component (B) is the sum of the two components per 100 parts by weight of vinyl chloride resin.
/! The agricultural vinyl chloride resin film according to claims (1") to (2), characterized in that the amount is within the range of 1 part by weight. (5) (Blend of 9 components) The amount is 0.0 relative to the total amount of component (A) and component (B).
The agricultural vinyl chloride resin film according to claims (1) to (2), characterized in that the polyvinyl chloride resin film has a ratio of /-/.