JPH09174652A - Polyvinyl chloride laminated film for agriculture and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a manufacturing process and prevent stains caused by bleeding of a plasticizer by adding a weathering agent and a drop preventing agent to each of pelletized or powdered polyvinyl chloride resin, adhesive resin and polyolefin resin, putting them in extruders, melting and extruding, thereafter extruding them simultaneously through one extruder die. SOLUTION: A weathering agent and a drop preventing agent are added to each of pelletized or powdered polyvinyl chloride resin 3, adhesive resin 2 and polyolefin resin 1. These are put in respective extruders, melted, and extruded. Thereafter, they are simultaneously extruded through one extruder die. For the weathering agent, a hindered amine or a benzophenone ultraviolet stabilizer is used. For the drop preventing agent, a fatty acid ester is used. Also, a blocking preventing agent is to be added to the polyolefin resin and the polyvinyl chloride resin, and it is preferable that a stearic acid amide and/or an ethylene bisamide is used or these are mixed with a calcium carbonate or a silicon dioxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyvinyl chloride laminated film for agriculture, and more particularly to co-extruding a polyolefin resin such as polyethylene and ethylene vinyl acetate copolymer and a polyvinyl chloride resin.
By adhering in the (on) step, the advantages of transparency, drip-proofing and heat retention of polyvinyl chloride and the stain resistance and durability of polyethylene or ethylene vinyl acetate copolymer can be realized at the same time. The present invention relates to an agricultural polyvinyl chloride laminated film that can be manufactured. Further, the present invention relates to a method for producing such an agricultural polyvinyl chloride laminated film by a single-step coextrusion step.

[0002]

2. Description of the Related Art Typical thermoplastic resins used as agricultural films include polyethylene, polyolefin resins such as ethylene vinyl acetate copolymers, polyvinyl chloride resins and the like. Among them, polyvinyl chloride resin is superior to polyolefin resins such as polyethylene and ethylene-vinyl acetate copolymer in drip-proof property, transparency, heat retention, mechanical strength, and weather resistance, which are characteristics as an agricultural film. However, since the plasticizer is leached out, the surface of the film is contaminated over time. On the other hand, a polyolefin resin such as polyethylene or ethylene-vinyl acetate copolymer has inferior properties such as drip-proof property to polyvinyl chloride resin, but it has excellent film processability, is inexpensive, and is stain resistant. And the cold resistance is extremely excellent.

Therefore, various patents have proposed a method for producing a laminated film for maximizing the film effect by combining only the advantageous properties of the polyvinyl chloride resin and the polyolefin resin. For example, Japanese Patent Laid-Open No. Sho 62
-220552 and JP-A-63-202662, polyvinyl chloride resin and sorbitan fatty acid ester,
Disclosed is an agricultural synthetic resin film in which polyglycerin fatty acid ester, pentaerythritol, etc. are added to improve the drip-proof property. However, these patents are limited to a method for producing a monolayer film which is formed into a flat film by a roll method.

Japanese Patent Laid-Open No. 4-202254 discloses that a film is formed by adding a hydrotalcite compound or the like to a polyvinyl chloride resin for heat retention and plate-out (plate-out) due to leaching of additives during processing. Disclosed is an agricultural film composition which has an improved effect of suppressing a phenomenon that a defect occurs or an additive is deposited on a processing machine. But,
This method is also a technology relating to a flat plate single-layer film for producing a film by a calendar method, and is not related to a coextrusion laminated film.

On the other hand, as another manufacturing technique of a laminated film using a polyvinyl chloride resin, European Patent No. 3302
No. 72 discloses an adhesive film for preventing leaching of a plasticizer by coating a polyvinyl chloride resin layer with a mixture of polyvinyl chloride resin and chlorinated polyethylene, which is also a single step coextrusion method. It has nothing to do with the production of laminated films according to.

[0006] British Patent No. 2024714 also discloses a method for producing an eight-layer film by combining four-layer films. However, since it is a method of coating a heat-fusible resin on an adhesive substrate film, This also has nothing to do with forming a film by the coextrusion process.

Japanese Patent Publication No. 5-63309 discloses a technique of using an adhesive when adhering a polyvinyl chloride resin sheet or film to a specific substrate. Here, a peeling phenomenon due to leaching of a plasticizer is disclosed. Therefore, an attempt was made to improve the adhesiveness by coating the surface of the polyvinyl chloride film with an electron beam-curable adhesive composition composed of an acrylic acid ester monomer, a methacrylic acid ester monomer, or the like. However, this method is far from the technique of forming a coextrusion film in a single step, and cannot be applied to agricultural films.

[0008]

The object of the present invention is to solve the above-mentioned problems of the prior art, in which a polyvinyl chloride resin is coextruded with a polyolefin resin to produce a film forming a layer. By simplifying the manufacturing process into a single process, the manufacturing cost can be reduced, and a method for manufacturing a polyvinyl chloride laminated film for agricultural use capable of fundamentally preventing contamination due to leaching of a plasticizer, etc. To provide.

In the present invention, a weathering agent and a drip-proofing agent are added to each of polyvinyl chloride resin, adhesive resin and polyolefin resin in the form of pellets or powder, and the mixture is put into each extruder and melt-extruded. The present invention relates to a method for producing a polyvinyl chloride laminated film for agriculture, which comprises coextruding through a die.

Further, the present invention provides (a) a degree of polymerization of about 800-17.
Phthalate-based, adipate-based or phosphate-based plasticizer about 3 parts by weight per 100 parts by weight of polyvinyl chloride resin of 00
Polyvinyl chloride resin containing 0-80 parts by weight, about 0.1-0.4 parts by weight of a Ba / Zn-based and / or phosphorous acid-based heat stabilizer and about 0.9-3.0 parts by weight of a drip-proofing agent. Layer; (b) Weathering agent about 0.
A polyolefin resin layer containing 3-1.0 parts by weight and selected from the group consisting of low-density polyethylene, linear (linear) low-density polyethylene, and ethylene-vinyl acetate copolymer; and (c) low-density polyethylene, direct Chain low density polyethylene, ethylene vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer, or ethylene / butyl acrylate copolymer with at least one unsaturated radically polymerizable polar monomer The present invention relates to a polyvinyl chloride laminated film for agriculture, which comprises an adhesive resin layer grafted as described above and formed between the polyvinyl chloride resin layer and the polyolefin resin layer.

The structure of the present invention will be described in more detail below. As mentioned above, the conventional polyvinyl chloride resin is mainly used for a single layer film, or it is generally used for manufacturing a film by adhering it to another resin by a method other than coextrusion using a coating agent or an adhesive. It was target.

[0012] Further, there has been a trial to manufacture a laminated film using a polyvinyl chloride resin by a single-step coextrusion method, but it failed because the effect could not be improved.
Until now, the biggest reason why laminated films or sheets using polyvinyl chloride resin could not be manufactured by the coextrusion method is that polyvinyl chloride resin is not sufficient for non-polar polymers such as polyolefin resins and other polar polymers. This is because they are not glued. In addition, in order to apply as a co-extrusion laminated film, polyvinyl chloride resin, polyolefin resin, etc. are melted in each extruder by using two or more extruders, and then cast or through one die of tube extrusion type. In this case, it is more difficult to apply the coextrusion process because the adhesive must be instantaneously adhered.

Therefore, in the present invention, an adhesive resin capable of appropriately laminating a polyvinyl chloride resin and a polyolefin resin such as polyethylene or ethylene vinyl acetate copolymer is selected and used, and it exhibits properties suitable as an agricultural film. Selectable weatherproofing agents and dripproofing agents. Such polyvinyl chloride resin, adhesive resin and polyolefin resin and additives are simultaneously melted, co-extruded and laminated through one tube extrusion die or a T-shaped casting die to obtain an agricultural polyvinyl chloride laminate according to the present invention. A film is manufactured.

In order to produce the polyvinyl chloride laminated film for agriculture according to the present invention, first, the components constituting the laminated film, that is, the polyvinyl chloride resin, the polyolefin resin and the adhesive resin are prepared.

The melting characteristics of polyvinyl chloride may greatly change depending on the degree of resin polymerization and the content of the plasticizer. As the degree of polymerization of the polyvinyl chloride resin increases and the content of the plasticizer decreases, the melt tension increases and the melt flow characteristics of the resin deteriorate. Therefore, an appropriate degree of resin polymerization and a plasticizer content are required in the extrusion process. Polyvinyl chloride resin has a degree of polymerization of about 80.
Resins in the range of 0 to 1700 are used alone or in combination,
The content of the plasticizer is about 30-80 parts by weight with respect to 100 parts by weight of the polyvinyl chloride resin, preferably the degree of polymerization of the resin is about 1000-1500, and the content of the plasticizer is about 40-7.
The condition must be 0 parts by weight. If the polymerization degree of the polyvinyl chloride resin is about 800-1200, which is relatively small, adjust the plasticizer content to about 30-60 parts by weight, and the resin polymerization degree is about 1300-1700. In the case of a large amount, it is preferable to add the content of the plasticizer at 50-80 parts by weight.

In the present invention, the plasticizer is DOP or DIN.
P, DIOP, DUP, DA _7-9 P, DA _9-11 P, DH
Phthalate system such as P, DOA, DHA, D
Adipate such as INA, DIDA, DUA
Phosphate system such as TCP, TXP, etc. is used. The above plasticizers are used alone or in combination of two or more.

Even if the degree of polymerization of the resin and the content of the plasticizer are appropriate conditions, there is a shear stress generated from the rotation of the screw and the inside of the die in the extruder, and the resin in the extruder and the die is Since there is a residence time, it is preferable to add an appropriate amount of heat stabilizer for heat stability. As the heat stabilizer, a Ba / Zn liquid or powder heat stabilizer and / or a phosphite heat stabilizer is used, and the content thereof is preferably about 0.1-4 parts by weight.
Further, when a tin-based heat stabilizer is mixed and added with a phosphorous acid-based heat stabilizer, higher heat stability can be obtained. In addition, it is preferable to add a lubricant in order to improve the melt flowability of the resin inside the extruder. As the lubricant, zinc stearate or calcium stearate is preferably added in the range of 0.4 parts by weight or less.

The polyolefin resin that adheres to the polyvinyl chloride resin eventually functions to protect the polyvinyl chloride resin from the external environment. As the polyolefin resin, one kind or two or more kinds are selected and used from the group consisting of low density polyethylene, linear low density polyethylene, and ethylene vinyl acetate copolymer. Among them, the low-density polyethylene has a melt index (melt index) of about 0.1-6.0 g / 10 min.
index), having a density of about 0.915-0.925 g / cc,
In the case of linear low density polyethylene, it is about 0.2-4.0 g / 1.
Melt index of 0 min., About 0.900-0.935
It has a density of g / cc and ethylene vinyl acetate copolymer is 1
Vinyl acetate content of -20% by weight and about 0.2-6.0 g / 1
It preferably has a melt index of 0 min. In each of the above-mentioned low-density polyethylene, linear low-density polyethylene, and ethylene-vinyl acetate copolymer, the density and the content of vinyl acetate are not so important, but the melt index is within an appropriate range (for example, 6.0 g / 10 min.). If it exceeds, there will be a difference in melt flowability with the polyvinyl chloride resin,
Coextrusion becomes difficult. In addition to the above resins, a high density polyethylene resin can be used for the coextrusion laminated film, but its use is limited because it has a drawback that the transparency of the laminating agent is impaired at the time of use and the commercial value is lost.

Various adhesive resins are used to bond the above-mentioned polyvinyl chloride resin and polyolefin resin.
Preferably low density polyethylene, linear low density polyethylene, ethylene vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer, ethylene / butyl acrylate copolymer, ethylene / methacrylate copolymer, etc. At least one kind of radically polymerizable unsaturated polar monomer
t) resin. Here, the radical-polymerizable unsaturated polar monomer is an ethylenically unsaturated carboxylic acid such as acrylic acid, methylacrylic acid, fumaric acid, itaconic acid, ethylacrylic acid, maleic acid, maleic anhydride, or an anhydride thereof. Is. At this time, the rate of grafting the polar monomer is preferably about 0.1-10% by weight, and the melt index of the final resin is preferably about 0.3-10 g / 10 min. Young, melt index 10g / 1
If it exceeds 0 min., A difference in the melting characteristics between the polyvinyl chloride resin and the polyolefin resin will occur during extrusion processing, making simultaneous extrusion difficult.

On the other hand, in order to apply it as an agricultural film, it is necessary to add a weathering agent so that the film will not be photooxidized even if it is exposed to agricultural land for about one year. As a weathering agent, HALS (Hindered Amine Light Stabi)
lizer) or a benzophenone type ultraviolet stabilizer is used, and the amount thereof is preferably about 0.3-1.0 parts by weight. On the other hand, it is more effective to add the ultraviolet stabilizer only to the polyolefin resin, or evenly add it to all three layers of the polyolefin resin, the adhesive resin and the polyvinyl chloride resin.

Then, a drip-proofing agent must be added so that water drops do not stay on the film surface. At this time, a fatty acid ester-based drip-proofing agent is preferable as the drip-proofing agent, and the addition amount thereof is about 0.9-3.0 parts by weight. On the other hand, the drip-proof agent may be added to all of the polyolefin resin, the adhesive resin and the polyvinyl chloride resin, or may be added to only two resins, but the drip-proof property when added only to the polyvinyl chloride resin Compared with, there is no significant increase effect on drip resistance.

On the other hand, when a laminated film is made of polyvinyl chloride and made of a tube extruded film, the double film is eventually wound together on a take-up roll.
At this time, it is preferable to add an antiblocking agent because the film is not easy to use if the film has poor opening properties. There are many types of anti-blocking agents, but if 0.4 parts by weight or more of an inorganic substance such as calcium carbonate or silicon dioxide is added, there is a risk of gel formation on the film surface, so exhibiting slipping property and anti-blocking property. It is preferable to add stearic acid amide and / or ethylenebisstamide of the amide series which can be used, or to use them in combination with calcium carbonate or silicon dioxide. The amount of anti-blocking agent used is preferably 0.2-1.0 parts by weight. Such antiblocking agent need not be added to the adhesive resin, but should be added to the polyolefin resin and polyvinyl chloride resin.

The various resins and additives thus selected are manufactured into a coextrusion laminated film for agriculture through a tube extrusion die or a T-shaped casting die through a coextrusion machine having three or more extruders. To be done.

The polyvinyl chloride laminated film having the above resin composition and additive composition can be used not only to produce a flat film by a usual calendering method but also to produce a tube extruded film by an inflation method.

The agricultural polyvinyl chloride laminated film according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic view of a polyvinyl chloride laminated film for agriculture according to the present invention, in which reference numeral 1 is a polyolefin resin layer, 2 is an adhesive resin layer, and 3 is a polyvinyl chloride resin layer. According to FIG. 1, the polyvinyl chloride laminated film for agriculture manufactured by the manufacturing method of the present invention comprises (a) a phthalate type, an adipate type, or 100 parts by weight of a polyvinyl chloride resin having a degree of polymerization of about 800-1700. About 30-80 parts by weight of phosphate plasticizer, Ba / Zn system and / or
Alternatively, a polyvinyl chloride resin layer (3) containing about 0.1-0.4 parts by weight of a phosphorous acid-based heat stabilizer and about 0.9-3.0 parts by weight of a drip-proofing agent; (b) about 0 parts of a weathering agent. A polyolefin resin layer (1) selected from the group consisting of low-density polyethylene, linear low-density polyethylene, and ethylene-vinyl acetate copolymer, including 0.3-1.0 parts by weight; and (c) low-density polyethylene, Linear low-density polyethylene, ethylene vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer or ethylene / butyl acrylate copolymer with at least one radically polymerizable unsaturated polar monomer The adhesive resin layer (2) is formed by grafting and is formed between the polyvinyl chloride resin layer (3) and the polyolefin resin layer (1).

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the technical scope of the present invention is not limited to the following Examples. Example 1 Polyvinyl chloride resin (P-1, manufactured by Hanwha Sogo Chemical Co., Ltd.)
To 100 parts by weight of 300 (degree of polymerization 1300)), 60 parts by weight of DOP (manufactured by Hanwha Sogo Chemical Co., Ltd.) was used as a plasticizer. As additives for improving thermal stability, 0.3 parts by weight of Ba / Zn type thermal stabilizers BZ-150T and BP-251S (both manufactured by Songwon Sangyo Co., Ltd.) were added. And TM-700N which is a tin-based heat stabilizer
1.0 parts by weight and PI-318 which is a phosphorous acid type heat stabilizer
Was added in an amount of 2.0 parts by weight. 0.1 parts by weight of zinc stearate and calcium stearate (both manufactured by Songwon Sangyo Co., Ltd.) were added as lubricants. UV531 (manufactured by Cytec) was added as a weather resistance agent in an amount of 0.5 part by weight, and sorbitan fatty acid ester was added as a drip-proof agent in an amount of 2.0 parts by weight. Furthermore, ethylene bis steamide (Henkel) as an anti-blocking agent
Was used in an amount of 0.5 part by weight. As the adhesive resin, a resin obtained by grafting about 2.0% by weight of acrylic acid on an ethylene vinyl acetate copolymer is used, and the melt index is 6.
It was 0 g / 10 min. As a weather resistance agent, 0.55 parts by weight of UV531 was added like a polyvinyl chloride layer. As a polyolefin resin, the melt index is 0.8 g /
A low density polyethylene (manufactured by Hanwha Sogo Chemical Co., Ltd.) having a density of 10 min. And a density of 0.920 g / cc was used. 0.553 parts by weight of UV531 was added as a weathering agent, and 0.2 parts by weight of calcium carbonate was added as an antiblocking agent. Selected resins and additives are shown in Table 1 below.
A three-layer film was produced through a co-extruder for a three-layer tube extruded film. The size of each extruder is 30mm, 40m
The tube extrusion die had a diameter of 75 mm. Adjust the expansion ratio to 2.0 and the film thickness to 0.0
8 mm. The processing temperature is 1 cylinder temperature of each extruder.
The die temperature was adjusted to 60-180 ° C and 190-210 ° C. The thickness ratio for each layer is 0.05 m for the inner polyvinyl chloride layer.
The screw rotation speed of each extruder was adjusted so that m, the middle layer of acrylic acid-grafted vinyl acetate copolymer resin layer was 0.015 mm, and the outer layer of low-density polydensity polyethylene layer was 0.015 mm.

Table 1. Resin layer resins conditions inner polyvinyl polyvinyl chloride for polyvinyl chloride laminate (polymerization degree: 1300) 100 parts by weight of DOP 60 parts by weight BZ-150T 0.3 parts by weight BP-251S 0.3 part by weight TM-700N 1.0 parts by weight PI-318 2.0 parts by weight Zinc stearate 0.1 parts by weight Calcium stearate 0.1 parts by weight UV531 0.5 parts by weight Sorbitan fatty acid ester 2.0 parts by weight Ethylene bisstamide 0 .5 parts by weight Middle layer Acrylic acid graft Base material: Ethylene vinyl acetate copolymer Vinyl acetate copolymer (Vinyl acetate content: 20wt%, Melt index: 20g / 10min) Grafter: Acrylic acid Graft ratio: 2.0% Melt index : 6.0 g / 10 min UV531: 0.5 parts by weight Outer layer Low density polyethylene Melt index: 0.8 g / 10 min Degrees: 0.920g / cc UV531: 0.5 parts by weight CaCO _3: 0.2 parts by weight

Polyvinyl chloride 3 produced in Example 1 above
-Layer film, single-layer flat plate film made of polyvinyl chloride resin (manufactured by Hanwha Sogo Chemical Co., Ltd.), and single-layer film made of low-density polyethylene resin (manufactured by Ilshin Chemical Co., Ltd.)
The various physical properties of were compared and tested as follows. (1) The mechanical properties of the film include tensile strength, stretching degree, and tear strength, which are determined by the universal tester 1122 (Universal Test).
er 1122) (Instron)
Measured according to STM D882. (2) The optical property of the film is Hazegrad XL-211 (Ha
zegrad XL-211) (Pacific Scientific Co.) to ASTM D1
Haze was measured according to 003. At this time, each film was left in the open field and then measured with time. (3) The weather resistance of the film is evaluated by an artificial weathering acceleration tester, an ultraviolet condenser (UV condenser) (Atlas).
FS40 UV lamp is used, the temperature and time of UV irradiation is 60 ° C for 8 hours, and the temperature and time of cooling are 40 ° C for 4 hours. The number of days to reach 50% of the rate value was measured. (4) For the drip-proof property of the film, a frozen and constant temperature water bath was used. For the film to be tested, a beaker having an inlet diameter of 15 cm was filled with about 2/3 of water. Beaker tilts about 15 °
I made it diagonal. The temperature of the outside of the beaker film and the temperature of the water inside the beaker are set to -4 ° C, 20 ° C for 4 hours, 5 ° C,
A cycle was placed at 40 ° C. for 8 hours, and the number of days was measured until 10% or more of the film surface area contained water droplets. (5) Adhesive strength is 10 cm in length and 25 mm in width with tape with excellent adhesion to polyvinyl chloride layer and low density polyethylene resin layer.
Universal tester 1122
(Instron Co.) was used to clip both sides of the tape, and the adhesive strength was measured while the speed was reduced to 200 mm / min. At this time, the conditions for measuring the adhesive strength were that the film was left in an oven at 50 ° C. and then measured over time. The results of testing the physical properties of the polyvinyl chloride laminated film by the above method are shown in Table 2 below.

Table 2. Physical Properties of Polyvinyl Chloride Laminated Film PVC PVC LDPE Item Laminated Film Single Layer Flat Plate Single Layer Film Tensile Strength Horizontal 290 280 250 (kg / cm ² ) Vertical 280 270 220 Stretch Ratio Horizontal 420 320 320 450 (%) Vertical 360 350 350 350 Tear strength Horizontal 69 58 75 (kg / cm ² ) Vertical 65 50 72 72 Days of weathering * 79 68 62 Number of days of drip ** 86 89 71 Haze (%) 0 days 2.8 2.0 8.5 Changes after 15 days 6.3 15.4 9.7 After 30 days 7.8 21.8 11.3 After 60 days 9.4 41.5 14.9 Adhesive strength 0 days Not measurable with complete adhesion Not applicable (kg / 25mm) 7 days later 〃 〃 15 days later 〃 〃 30 days later 〃 〃 * Weather resistance days: The number of days that the residual stretching ratio of the film after UV irradiation by UV condensation is 50% of the initial stretching ratio ** Drip-proof days: until 10% of water drops stay on the film Days Irumu thickness: 0.08mm

From Table 2 above, the polyvinyl chloride laminated film according to the present invention is superior or equivalent in transparency, drip-proofness and weather resistance to other monolayer films, and the advantages of each resin used are maximized. I was able to confirm that. Therefore, the polyvinyl chloride laminated film for agriculture according to the present invention can maximize the respective advantages of the polyvinyl chloride resin and the polyethylene or the polyolefin resin such as the ethylene vinyl acetate copolymer. By manufacturing the laminated film in one extrusion step, there is an advantage that the manufacturing cost can be greatly reduced as compared with the case where the polyvinyl chloride laminated film is manufactured by the existing coating method.

[Brief description of the drawings]

FIG. 1 is a schematic view of a polyvinyl chloride laminated film for agriculture according to the present invention.

[Explanation of symbols]

 1 Polyolefin resin layer 2 Adhesive resin layer 3 Polyvinyl chloride resin layer

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location B32B 27/32 B32B 27/32 Z C08K 5/00 KGP C08K 5/00 KGP C08L 27/06 LES C08L 27/06 LES // B29K 27:06 B29L 7:00 9:00 (72) Inventor Wang Ki-Hyun, Daejeong, Kwangyuk-si, South Korea, Shinsung 152-1, Derim Duore Apartment 108 Dong 803, Ho (72) Inventor, Li Jaeho, Daejeon Gwangyok-si Yusung Shinsung-dong 152-1 Derimdule Apartment 107 Dong 1102ho (72) Inventor Yong Kyung-jun South Korea Daejeong-gwangyuk-sung Shinsung-dong 152-1 Derimdule Apartment 110dong 407ho

Claims (18)

[Claims] 1. A pellet or a powdered polyvinyl chloride resin, an adhesive resin, and a polyolefin resin, to which a weathering agent and a drip-proofing agent are added, and the mixture is put into each extruder and melt-extruded. A method for producing a polyvinyl chloride laminated film for agriculture, which comprises coextruding through an extrusion die. 2. The weathering agent is a HALS or benzophenone-based UV stabilizer, and the addition amount thereof is about 0.3.
The method according to claim 1, wherein the amount is 1.0 part by weight. 3. The method according to claim 1, wherein the weather resistance agent is added only to the polyolefin resin or to all of the polyvinyl chloride resin, the adhesive resin and the polyolefin resin. . 4. The method according to claim 1, wherein the drip-proofing agent is a fatty acid ester-based drip-proofing agent, and the addition amount thereof is about 0.9-3.0 parts by weight. 5. The drip-proofing agent is added only to the polyvinyl chloride resin or to two or more resins selected from polyvinyl chloride, adhesive resins and polyolefin resins, The method according to claim 1 or 4. 6. The method according to claim 1, wherein an antiblocking agent is further added to all of the polyvinyl chloride resin, the adhesive resin and the polyolefin resin. 7. The stearic acid amide and / or ethylenebisstamide is used as the antiblocking agent, or is mixed with calcium carbonate or silicon dioxide and used in an amount of 0.2-1. Method according to claim 6, characterized in that it is 0 parts by weight. 8. The method according to claim 6, wherein the antiblocking agent is added to the polyvinyl chloride resin and the polyolefin resin. 9. The polyvinyl chloride resin is about 800-1.
It has a degree of polymerization of 700 and further contains about 30-80 parts by weight of a phthalate-based, adipate-based or phosphate-based plasticizer and B.
a / Zn heat stabilizer and / or phosphorous acid heat stabilizer of about 0.
Method according to claim 1, characterized in that it comprises 1-0.4 parts by weight. 10. The polyvinyl chloride resin further contains 0.4 parts by weight or less of zinc stearate or calcium stearate as a lubricant.
The described method. 11. The adhesive resin is low density polyethylene, linear low density polyethylene, ethylene vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, ethyl / methyl acrylate copolymer, ethylene / butyl acrylate copolymer. Alternatively, at least one kind of radically polymerizable unsaturated polar monomer is grafted onto an ethylene / methacrylate copolymer, and the polar monomer is acrylic acid, methyl acrylic acid, fumaric acid, itaconic acid, ethyl acrylic. Acid, maleic acid, maleic anhydride and those selected from the group consisting of these anhydrides,
The method of claim 1, wherein the polar monomer is grafted at a rate of about 0.1-10% by weight. 12. The olefin resin is selected from the group consisting of low density polyethylene, linear low density polyethylene, and ethylene acetic acid copolymer.
The described method. 13. The polyolefin resin as a low density polyethylene having a melt index of about 0.1-6.0 g / 10 min. And a density of about 0.915-0.925 g / cc. The method according to claim 12. 14. The polyolefin resin as a linear low-density polyethylene having a melt index of about 0.2-4.0 g / 10 min. And a density of about 0.900-0.935 g / cc. 13. The method according to claim 12. 15. The polyolefin resin having a vinyl acetate content of about 1-20% by weight as an ethylene-vinyl acetate copolymer and a melt index of about 0.2-6.0 g / 10 min. The method according to claim 12. 16. The method according to claim 1, wherein a tube extrusion die or a casting die is used in the production of the laminated film. 17. A phthalate-based resin, based on 100 parts by weight of (a) a polyvinyl chloride resin having a degree of polymerization of about 800-1700,
Adipate-based or phosphate-based plasticizer About 30-8
A polyvinyl chloride resin layer containing 0 parts by weight, about 0.1-0.4 parts by weight of a Ba / Zn-based and / or phosphorous acid-based heat stabilizer and about 0.9-3.0 parts by weight of a drip-proofing agent; b) a polyolefin resin layer containing about 0.3-1.0 parts by weight of a weathering agent and selected from the group consisting of low density polyethylene, linear low density polyethylene and ethylene vinyl acetate copolymer; and (c) low density polyethylene. , Linear low-density polyethylene, ethylene vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer or ethylene / butyl acrylate copolymer, at least an unsaturated polar monomer capable of radical polymerization. An agricultural polyvinyl chloride laminated film, comprising one or more kinds of grafted polyvinyl chloride resin layers and an adhesive resin layer formed between the polyvinyl chloride resin layer and the polyolefin resin layer. Beam. 18. The polyvinyl chloride resin layer further comprises a weathering agent and an antiblocking agent, the polyolefin resin layer further comprises a dripproofing agent and an antiblocking agent, and the adhesive resin layer further comprises a weathering agent and a dripproofing agent. The film according to claim 17, which further comprises an agent.