JPH0420218A - Agricultural vinyl chloride resin film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to an agricultural vinyl chloride resin film.

More specifically, the present invention relates to an agricultural vinyl chloride resin film that has improved durability against undesirable deterioration phenomena such as discoloration, embrittlement, and reduction in dust resistance caused by stretching outdoors.

``Prior art'' In recent years, farmers cultivating useful plants have widely adopted methods of promoting or suppressing the cultivation of useful plants in greenhouses or tunnels in order to improve profitability. became.

The covering materials for this greenhouse or tunnel include polyethylene film, ethylene-hinyl acetate copolymer film, polyester film, polycarbonate film, hard and soft vinyl chloride resin film,
Glass etc. are used. Among them, soft vinyl chloride resin film is widely used because it has the best overall light transmittance, heat retention, mechanical strength, durability, and workability compared to other synthetic resin films. ing.

However, synthetic resin films used as covering materials for greenhouses or tunnels, including vinyl chloride resins, can be affected by the sun's rays, especially ultraviolet rays, after a year has passed since they have been used as covering materials. Due to this, please be aware of changes over time such as deterioration of appearance and decrease in film flexibility. Furthermore, recent improved agricultural techniques, especially economics,
Labor-saving agricultural techniques are increasingly requiring coating materials to withstand even harsher conditions than in the past.

Therefore, for the purpose of improving weather resistance, a technique of adding and blending an organic phosphate ester or an organic phosphate metal salt to a vinyl chloride resin as a base material to form a film is widely used.

On the other hand, depending on the region and location where soft vinyl chloride resin films are used for agricultural purposes, the dust-proofing of the outside surface of greenhouses or tunnels may deteriorate after two years have passed since the start of use. is significantly reduced, making it unusable.

As a method to eliminate the above drawback, a method has been proposed in which the surface of an agricultural vinyl chloride resin film is coated with a specific resin or paint as described below.

(1) Method of applying acrylic resin (Special Publication Publication No. 46-2
(11) Method of applying fluororesin through an adhesive layer (JP-A-56-86748, JP-A-57-81.55)
(3) Method of applying a mixture of fluororesin and acrylic resin (Japanese Patent Application Laid-Open No. 63-21.1.43, JP-A-46-65161) Publications, Japanese Patent Publication No. 63-236, etc.) However, i) is not sufficient to prevent the plasticizer of the base material from bleed-out to the surface of the molded product, and (ii)
), the fluororesin and the base material were not bonded and integrated in a practically sufficient manner even through the adhesive layer due to the influence of the plasticizer and the like migrating to the adhesive layer.

(iii) was proposed as an improvement to these, but it was found that the interfacial adhesion between the base material and the fluororesin mixture was insufficient, and the acrylic resin and fluororesin were difficult to dissolve, resulting in an opaque coating film. There were drawbacks.

1. Problems to be Solved by the Invention" Under such circumstances, the present inventors have found that undesirable deterioration phenomena such as discoloration, embrittlement, and reduction in dustproof and antifogging properties caused by stretching outdoors are significantly With the aim of providing an agricultural vinyl chloride resin film with improved properties and durability, the present invention has been completed as a result of intensive studies.

``Means for Solving the Problems'' Therefore, the gist of the present invention is to apply acrylic acid or methacrylic acid to one or both sides of a vinyl chloride resin film containing an organic phosphate ester or an organic phosphate metal salt. Acrylic resin [A] obtained by polymerizing a mixture containing 60 parts by weight or more of alkyl esters of 116 and acrylic acid or methacrylic acid alkyl esters
Fluorine-containing acrylic resin (Bl
An agricultural vinyl chloride resin film is characterized in that it is formed with a coating of a composition containing the following two components as main components.

The present invention will be explained in detail below.

(2) Vinyl chloride resin In addition to polyvinyl chloride, vinyl chloride resin refers to a copolymer whose main component is vinyl chloride.

Examples of monomer compounds copolymerizable with vinyl chloride include vinylidene chloride, ethylene, propylene, acrylonitrile, maleic acid, itaconic acid, acrylic acid, methacrylic acid, and vinyl acetate. These vinyl chloride resins may be produced by any of conventionally known production methods such as emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization.

In order to impart flexibility to the vinyl chloride resin serving as the base, 20 to 60 parts by weight are added to 100 parts by weight of the resin.
Parts by weight of plasticizer are incorporated. By adjusting the blending amount of plasticizer within the above range, the desired soft vinyl chloride molded product can be produced.
It can provide excellent flexibility and mechanical properties.

Examples of the plasticizer include phthalic acids such as di-n-octyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, diisodecyl phthalate-1., dioctyl phthalate, and diundecyl phthalate-1.
7 bodies; isophthalic acid derivatives such as dioctyl phthalate;
Adipic acid derivatives such as di-n-butyl adipate-1, dioctyl adipate; maleic acid derivatives such as dibutyl maleate; citric acid derivatives such as tri-n-butyl syl-1-late; itaconic acid derivatives such as monobutyl icconate; butyl Oleic acid derivatives such as oleate; Ricinoleic acid derivatives such as glycerin monolysyllate; Others,
Examples include epoxidized soybean oil and epoxy resin plasticizers.

In the agricultural vinyl chloride resin film of the present invention, an organic phosphate ester or an organic phosphate metal salt is blended with the vinyl chloride resin described in 1.

Examples of organic phosphoric acid esters include triisopropylphenyl bosphate, isodecyl diphenyl phosphate,
Tricresyl bosphate, l-lis(isopropylphenyl) bosphate, tributyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl bosphate, octyldiphenyl phosphate-1, tricylenyl bosphate, etc. Among these, tricresyl phosphate and tricylenyl phosphate are particularly preferred.

The above organic phosphate esters can be used alone or in the form of a composite. Specifically, a composite of an organic phosphoric acid ester and an organic phosphite may be mentioned, and the organic phosphorous ester also includes a phosphonate-based compound such as diphenylphosphonate.

The organic phosphate metal salt is represented by the general formula [I] or [■] (wherein, M means zinc, calcium, barium, magnesium, cobalt or strontium, and R1, R2 and R3 are (respectively means alkyl, aryl, arylalkyl, alkylaryl, or an alkyl group having an ether bond).

Examples of the alkyl group represented by R' isooctyl, 2-ethylhexyl, decyl, isodecyl, lauryl, tridecyl, C1゜~C1ff mixed alkyl, stearyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl,
Examples include 4-methylcyclohexyl group.

Examples of aryl groups include phenyl and naphthyl groups.

Examples of the argyl group include benzyl, β-phenylethyl, α-phenylpropyl, and β-phenylpropyl groups.

Examples of alkylaryl groups include tolyl, xylyl,
Examples include ethylphenyl, butylphenyl, tert-butylphenyl, octylphenyl, isooctylphenyl, tertiary octylphenyl, nonylphenyl, 2,4-di-tert-butylphenyl, and the like.

Examples of the alkyl group having an ether bond include furfuryl, tetrahydrofurfuryl, 5-methylfurfuryl, and α-methylfurfuryl, or methyl, ethyl,
Isopropyl, butyl isobutyl, hexyl, cyclohexylphenyl cellosolve residue; Methyl, ethyl isopropyl, butyl, isobutyl calpitol residue; Triethylene gelcol monomethyl ether, -
Monoethyl ether, -monobutyl ether residue; glycerin 1,2-dimethyl ether, -monoethyl ether, -monobutyl ether residue; glycerin 1,2-dimethyl ether, 1,3-diethyl ether, -1-ethyl- 2-propyl ether residue; nonylphenoxypolyethoxyethyl, lauroxyboriethoxyethyl residue, etc.

Further, the metal represented by M is particularly preferably zinc, calcium and barium.

These organic phosphate esters or organic phosphate metal salts may be used alone or in combination.

In the agricultural film of the present invention, it is most preferable to use an organic phosphate ester and an organic phosphate metal salt in combination in terms of film formation properties and outdoor extensibility.

The amount of organic phosphate ester or organic phosphate metal salt is:
It is selected within the range of 0.1 to 15 parts by weight, preferably within the range of 0.2 to 10 parts by weight, based on 100 parts by weight of the vinyl chloride resin. If the amount is less than 0.1 part by weight, the weather resistance and dustproof properties of the soft vinyl chloride resin film will not improve. If the amount is more than 15 parts by weight, the transparency of the film will be extremely poor, which is not preferable. 0 within the above range
．． Particularly preferred is a range of 2 to 8 parts by weight.

In addition to the above-mentioned plasticizer, organic phosphate ester, or organic phosphate metal salt, the vinyl chloride resin may include, if necessary, known resin additives that are usually blended into synthetic resins for molding. For example, lubricants, heat stabilizers, ultraviolet absorbers, light stabilizers, antioxidants, stabilizing aids, antistatic agents, antifogging agents, antifungal agents, antialgae agents, inorganic fillers, colorants, etc. are added. be able to.

Examples of lubricants, heat stabilizers, and antioxidants that can be incorporated into the film of the present invention include polyethylene wax, bisamide compounds, liquid paraffin, organic phosphite compounds, and β-diketone compounds.

The above various resin additives can be used alone or in combination.

The amount of the various resin additives mentioned above can be selected within a range that does not deteriorate the properties of the film, usually within a range of 10 parts by weight or less based on 100 parts by weight of the base vinyl chloride resin.

To blend the plasticizer, organic phosphate ester or organic phosphate metal salt, and other resin additives into the vinyl chloride resin that will serve as the base of the film, weigh the necessary amounts of each and use a ribbon blender or hand mixer. A conventionally known compounding machine or mixer such as a blender, super mixer, etc. may be used.

In order to form a film from the resin composition obtained in the above manner, a method known per se, such as a melt extrusion method (T~
(including Gouy method and inflation method), calendar molding method, /8 liquid casting method, etc.

2. Acrylic resin [A] 2-1. Examples of the alkyl esters of the acrylic monomer acrylic acid or methacrylic acid include methyl acrylate, ethyl acrylate, n
-propyl acrylate, 1so-propyl acrylate, n-butyl acrylate, 1sO-butyl acrylate-1~, cyclohexyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, dodecyl acrylate, tridecyl acrylate, stearyl acrylate-1~, etc. C0-C22 alkyl esters of acrylic acid such as - methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, 1so-propyl methacrylate-1, n-butyl methacrylate, 1sO
Examples include alkyl esters of C+ "" C2□ of methacrylic acid such as -butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, decyl methacrylate, dodecyl methacrylate, tridecyl methacrylate, stearyl methacrylate, and the like.

2-2. The blended acrylic resin [A] is obtained by polymerizing a mixture containing 60 parts by weight or more of the alkyl ester of acrylic acid or methacrylic acid described in 2-1. If the amount of the alkyl ester of acrylic acid or methacrylic acid is less than this amount, the water resistance of the formed film will not be sufficient.

In addition, other monomers copolymerizable with the monomers can be blended into the monomer mixture.

Other monomers include α, β-ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, crotonic acid, and icconic acid; , β-ethylenically unsaturated sulfonic acids; 2-acrylamido-2-methylpropanoic acid: α, β-ethylenically unsaturated phosphonic acids; hydroxyl group-containing vinyl monomers such as hydroxyethyl acrylic acid or tsucrylic acid; acrylonitriles ; Acrylamide frequently; Glysodyl esters of acrylic acid or methacrylic acid, etc. Even if these monomers are used alone,
Alternatively, two or more types may be used in combination.

3. Fluorine-containing acrylic resin CB) 3-1゜Perfluoroalkyl group-containing acrylic monomer acrylic acid or methacrylic acid perfluoroalkyl esters include 2.22-trifluoroethyl acrylate , 2,2.2-1-lifluoroethyl methacrylate, 2,2,3.3-tetrafluoropropyl acrylate, 2.2.3.3-tetrafluoropropyl methacrylate, 2.2.3.3.3- Pentafluoropropyl acrylate-1, 2.2, 3.3
．． 3-pentafluoropropyl methacrylate, 1-trifluoromethyl-2,2,2-)lifluoroethyl acrylate, 1-trifluoromethyl-2,2,2-trifluoroethyl acrylate, 2.2.3.3.4 .4
5.5-octafluoropentyl acrylate, 2,2
3, 3.4.4.5.5-octafluoropentyl methacrylate, 22,3,3,4.4-hexafluorobutyl acrylate, 2,2,3,3,4.4-hexafluorobutyl acrylate, 2 -perfluorooctyl ethyl acrylate, 2-perfluorooctyl methacrylate-I., 2-perfluorononylethyl acrylate, 2-perfluorononylethyl methacrylate, and the like. Among these, those in which the number of fluorine atoms in the perfluoro group is 5 or more are particularly preferred.

These may be used alone or in combination of two or more.

3-2. The blended gold fluorine acrylic resin [B] is an alkyl ester of acrylic acid or methacrylic acid described in 2-1 60-9
A mixture containing 5 parts by weight and perfluoroalkyl esters of acrylic acid or methacrylic acid described in 3-1 40
It is obtained by polymerizing a mixture containing ~5 parts by weight.

If the amount of the alkyl ester of acrylic acid or methacrylic acid is less than the above amount, the miscibility with the acrylic resin (Al) will be poor, and the transparency of the film formed will be insufficient, and if it is more than the amount specified in 1. The effect of the coating on dustproofness and weather resistance is not sufficient, which is undesirable.

In addition, other monomers copolymerizable with the monomer described in 2-2 can be blended into the monomer mixture.

4. Polymerization of resin [A] and resin [B] Acrylic resin [A] and fluorine-containing acrylic resin (1
No. 33 is obtained by charging the mixture together with an organic solvent in a polymerization can, adding a polymerization initiator and, if necessary, a molecular weight regulator, and heating and polymerizing with stirring. For polymerization, generally known methods such as suspension polymerization and solution polymerization are employed.

Examples of organic solvents used in polymerization include methanol, ethanol, n-propanol, isopropanol, n-butanol, 5ec-butanol, tert-butanol, n-propanol,
-amyl alcohol, isoamyl alcohol, tert
- Alcohols such as amyl alcohol, n-hexyl alcohol, cyclohexanone; Hensen, toluene,
Aromatic hydrocarbons such as xylene; Acetate esters such as ethyl acetate and butyl acetate; Acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isobutyl ketone, diethyl ketone, 2-hexanone, 3-hexanone, di-n- Ketones such as propyl ketone, diisopropyl ketone, di-n-amyl ketone, cyclohexanone;
There are tetrahydrofuran, etc., and these are one or two types.
Can be used in combination of more than one species. Examples of usable polymerization initiators include radical-generating catalysts such as α,α-abbisisobutyronitrile, hensyl peroxide, and cumene hydroperoxide;
For negative effects, methyl mercaptan, mercaptan,
tert-dodecyl mercaptan, β-mercaptoethanol 5, coating 5-1. Covering polymerized acrylic resin [A] and fluorine-containing acrylic resin CB)
The solid weight ratio of the former is 40 to 99 to the latter 60 to 1 (the total amount of both is 100), and a particularly preferable ratio is 50 to 98 to 50 to 2. . If the blending ratio of the former is higher than this, it is not preferable because the dustproof properties and weather resistance of the formed film cannot be sufficiently improved. On the other hand, if the blending ratio of the former is less than this, the permeability of the formed film will not be sufficient and the cost will be high, which is not preferable because the effect obtained is not large compared to the increase in cost.

In addition to these components, the above coating composition contains auxiliary components such as antioxidants, neutralizers, ultraviolet absorbers, light stabilizers, antistatic agents, pigments, dyes, fungicides, and algaecides. , a foaming agent, a lubricant, etc., and can be used by dispersing and/or melting in an organic solvent.

Examples of solvents include aliphatic hydrocarbons such as heptane and cyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene; alcohols such as methanol, ethanol, isopropyl alcohol, and polyoxyethylene glycol; and halogenated hydrocarbons. Chloroform, tetrachlorinated hydrocarbons, chlorhenzene, etc.; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone; esters such as methyl acetate, allyl acetate, ethyl stearate; amines such as trimethylamine, diphenylamine, hexamethylene diamine, etc. Examples include dimethylformamide, dimethylacetamide, dioxane, diethyl ether, diethylene dithioglycol, diacetone alcohol, hendinitrile, dimethyl sulpoxite, etc., and these can be used alone or in combination of two or more.

5-2, Film formation To form a film on the surface of a vinyl chloride resin film,
Various known methods are applied depending on the shape of the molded product.

For example, when forming a film in a solution state, a doctor blade coating method, a gravure roll coating method, an air knife coating method, a reverse roll coating method, a dip coating method, a curtain roll coating method, a spray coating method,
A coating method such as a rond coat method is used.

In addition, when forming the coating composition described in 5-1 as a single coating in addition to the solution state, a coextrusion method, an extrusion coating method, an extrusion lamination method, and a lamination method are used. When a coating method is used as a film forming method, drying methods for the solvent include, for example, natural drying method, hot air drying method,
There are infrared drying methods, far infrared drying methods, etc., but the drying speed,
The hot air drying method is advantageous from the viewpoint of safety. The temperature conditions in this case are in the range of 50 to 150°C, and the time is 10
It is best to choose between seconds and 15 minutes.

In the present invention, the thickness of the coating formed on the surface of the base film is preferably 1/10 or less of the thickness of the base film. If the thickness of the coating is more than 1/10 of the base film, there is a difference in flexibility between the base film and the coating, so phenomena such as peeling of the coating from the base film are likely to occur, and cracks may occur in the coating. This is undesirable because a phenomenon occurs in which the strength of the base film decreases.

In addition, before applying the above coating composition, the surface of the soft vinyl chloride resin film may be washed with alcohol or water, subjected to plasma discharge treatment or corona discharge treatment, or undercoated with another paint or a primer. Pretreatment such as the following may be performed.

When the agricultural vinyl chloride resin film according to the present invention is actually used for agricultural purposes, when the coating is formed on only one side, the side on which this coating is provided will be the outside of the greenhouse or tunnel. Use it as follows.

“Examples” 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 5, Comparative Examples 1 to 5 1.
．． 400) 100 parts by weight Diocnal phthalate 50 Epoxidized soybean oil 3 Barium-zinc composite liquid stabilizer 1.5 Barium stearate
0.2〃Zinc stearate 0
．． A resin composition consisting of 4-solhitane laurate 1.524-dihydroxyhenduphenone 0.5 was prepared, and an organic phosphate ester or an organic phosphate metal salt of the type and amount shown in Table 2 was blended. .

After stirring and mixing each formulation for 10 minutes using a supermimicr, the mixture was kneaded on a mill roll heated to 80'C to a thickness of 0. ] A 5 mm base film was prepared.

■、Ekuhada p-thread l] u-L-LIJL In a reactor equipped with a thermometer, a stirrer, a reflux condenser, and a nozzle for adding raw materials, 70 parts by weight of methyl ethyl ketone, 30 parts by weight of toluene, and 1 part by weight of benzoyl peroxide. 0.0 parts by weight and 100 parts by weight of a mixture of each monomer shown in Table 1 were charged, and while stirring in a nitrogen gas stream, 0.5 parts by weight of benzoyl peroxide was added at 70°C for 3 hours. The reaction was continued at the same temperature for about 3 hours to obtain resins a''-c, which are acrylic resins.

70 parts by weight of methyl ethyl ketone was added to a reactor similar to ■.
] - 30 parts by weight of toluene, 1.0 parts by weight of benzoyl peroxide, and 100 parts by weight of the mixture of each monomer shown in Table 1 were charged, and the mixture was further heated at 80°C for 3 hours while stirring in a nitrogen gas stream. Benzoyl peroxide f was obtained.

■, Mukaiya Castle on the side - Blend acrylic resin [A] and fluorine-containing acrylic resin [B] of the type and amount shown in Table 2, and add methyl ester to the mixture so that the solid content is 20% by weight. Spray ketone was added to obtain a coating composition.

The coating composition described above was applied to one side of each base film prepared by the method described in AiJ using a #5 bar coater. The applied film was held in ozone at 130°C for 1 minute to volatilize the solvent.

The amount of coating on each film obtained was approximately 3g1rd.

The performance of the film was evaluated in the following manner and the results are shown in Table 2.

Initial Appearance The appearance of the film was observed with the naked eye. The evaluation criteria are as follows.

◎...Colorless and with excellent transparency.

○: Slightly white, but transparent.

△: White and semi-transparent.

×...Things that are cloudy and devitrified.

Flexibility of the coating Each film was cut into 5 cm width and 15c+n length,
It was folded back alternately at 2 cm intervals in the direction perpendicular to the length direction. In this state, a load of 2 kg was applied from above and the sample was left in a constant temperature bath maintained at 15°C for 24 hours. Then, the load was removed, the folds of the film were stretched out, and the appearance of the film was observed with the naked eye. The results are shown in Table ψ. The evaluation criteria for this test are as follows.

◎ ...No change is observed in the coating at the crease.

△...Cracks are observed in the film at the crease.

×: Significant cracks are observed in the coating at the creases.

The 10 types of films tested for outdoor expansion were installed in a roof-type house (frontage 3 m, depth 5 m, ridge height 1.5 m) in a test field in Shigun, Mie Prefecture.
, a roof slope of 30 degrees) was coated with the coated surface facing the outside of the greenhouse, and an expansion test was conducted for two years from April 1983 to March 1990.

The stretched film was subjected to an external appearance test and the elongation retention rate of the film was measured by the following method, and the dust resistance of the film during the stretching test was evaluated.

Appearance of the film: Appearance observed with the naked eye.

The evaluation criteria are as follows.

◎...No changes in appearance such as discoloration are observed.

○...Some changes in appearance such as slight discoloration are observed.

／\　... Items with significant changes in appearance such as discoloration.

×: Discoloration is observed on the entire surface.

Elongation retention rate of film: means a value calculated by the following formula.

Dust resistance: means the value calculated using the following formula.

*Direct light transmittance at a wavelength of 555 mμ (manufactured by Hitachi, EPS-20 model used) The measurement results were displayed as follows.

◎...The light transmittance after expansion is 90% or more of that before expansion.

○...The light transmittance after expansion is in the range of 70 to 89% of that before expansion.

Δ...The light transmittance after stretching is in the range of 50 to 69% of that before stretching.

×: The light transmittance after stretching is less than 50% of that before stretching.

＼ ＼ "Effects of the Invention" As is clear from the examples above, the present invention has the following effects, and its agricultural utility value is extremely large.

(1) Even when the agricultural vinyl chloride resin film according to the present invention is stretched outdoors for a long period of time, there is little discoloration, deterioration in physical properties, or deterioration in dust resistance, and it can be used for a long period of time.

(2) The agricultural vinyl chloride resin film according to the present invention has excellent adhesion between the base film and the coating derived from a specific acrylic resin coating composition formed on its surface, so that the coating can be peeled off. It is difficult to clean and can withstand long-term use.

Patent applicant: Mitsubishi Kasei Vinyl Co., Ltd. Representative Patent Attorney Hase J (1 other person)

Claims (1)

[Claims] (1) On one or both sides of a vinyl chloride resin film containing an organic phosphate ester or an organic phosphate metal salt,
Acrylic resin [A] obtained by polymerizing a mixture containing 60 parts by weight or more of alkyl esters of acrylic acid or methacrylic acid, 60 to 95 parts by weight of alkyl esters of acrylic acid or methacrylic acid, acrylic acid or methacrylic acid Perfluoroalkyl esters of 40~
An agricultural vinyl chloride resin film on which a film of a composition whose main components are fluorine-containing acrylic resin [B] obtained by polymerizing a mixture of 5 parts by weight is formed.