FR2727975A1 - POLYOLEFIN RESIN WALL FILM AND USE THEREOF IN TREATMENT AND CULTURE PROCESS - Google Patents

Abstract

A polyolefin resin wall film comprising a polyolefin resin, a hindered amine compound, a hydrotalcite-type compound, and a UV absorbing agent which is used to form the walls of a greenhouse or a protected horticulture tunnel which is not damaged by an inorganic sulfur agent applied in the greenhouse or in a tunnel for treating soil and / or plants, a process for treating the soil and / or plants in such a greenhouse or such a tunnel, and a method for growing plants in such a greenhouse or tunnel.

Description

The present invention relates to a wall film made of polyolefin resin

  not being damaged by inorganic sulfur-containing agents for treating soil or plants, a method for treating soil or plants in horticultural greenhouses or tunnels protected by an inorganic sulfur agent and a method of cultivating plants in greenhouses or tunnels for

  protected horticulture which includes such treatment of soils or plants.

  Until now the agricultural films used to build the walls of greenhouses or tunnels in protected horticulture and gardening are films of poly (vinyl chloride), polyolefin resins (for example polyethylene film) or copolymer films ethylene vinyl acetate. In particular, polyvinyl chloride films are widely used in Japan

for this reason.

  The purpose of protected horticulture is to allow planting and cultivation of plants in a season when growing outdoors is impossible or to increase crop productivity in a season when productivity is low, thanks to the artificial maintenance of an atmosphere suitable for crops. To do this, it is necessary to establish conditions such as the amount of light, the temperature, the humidity, the concentration of carbon dioxide, the amount of water, the type of soil, etc., which are compatible with the growth properties of crops, taking into account the economic return. The properties required for a material intended to form the walls of an artificial space such as a greenhouse vary with its use and the applications envisaged, and also according to the type of plants. For example, the main properties of a film used as the main material for the walls of a greenhouse or tunnel or insulation curtain used inside the greenhouse or tunnel include weathering (ie the ability to withstand outdoor use which involves exposure to sunlight for a long time), non-stick properties (to prevent degradation of transparency caused by deposition on the surface internal film of water droplets formed by condensation due to high humidity in the greenhouse or tunnel), heat retention properties (to maintain a high temperature in

  greenhouse at night), and light transmission properties (transparency).

  The growing interest of public opinion on the global protection of the environment is accompanied by a growing interest in polyolefin resin films which can be totally destroyed by combustion without release of toxic gases, unlike in the case of films. poly (chloride of

  vinyl) which, during their combustion, give off hydrogen chloride.

  In addition, polyolefin resin films have mechanical properties (e.g., tear strength, cold resistance, etc.), weather resistance, and thermal stability superior to polyvinyl chloride films. This is why the films now used to form the walls of greenhouses or tunnels consist mainly of resin films.

  polyolefin and no longer by polyvinyl chloride films.

  It has been found that polyolefin resin films that have been widely used in recent years have a serious deterioration in durability due to agrochemicals. Japanese Patent Application Laid-Open No. Kokai No. 175072/1988 discloses an agricultural film containing a thermoplastic resin which contains a hindered amine compound and a hydrotalcite-like compound to impart resistance to agrochemicals such as sulfur-containing agents to the film. organic, organic chlorinated agents

  and organic phosphorus agents.

  In recent years, in accordance with the growing trend to reduce the amounts of agrochemicals used, it is used in increasing amounts of inorganic sulfur compounds very conventional such as the sulphocalcium slurry, the sulfur flower, hydrated sulfur compounds and fumigants based on sulfur to meet consumer demand

  concerning safety and nature protection.

  As in the case of the use of organic agrochemicals, the use of such inorganic sulfur-containing agents often degrades the weatherability of polyolefin resin agricultural films and the agricultural film of the published Japanese patent application Kokai 175072/1988 does not necessarily retain weather resistance

  sufficient when using inorganic sulfuric agents.

  If such a film used in horticulture breaks as a result of deterioration during a significant period such as the fruit period,

  is a serious problem because fruit trees are perennials.

  It is an object of the present invention to provide a polyolefin resin film consisting of an environmentally safe polyolefin resin and useful as a wall film for greenhouses or tunnels for protected horticulture in which inorganic sulfuric agents and

  reduced quantities of organic agrochemicals.

  In a first aspect, the present invention provides a polyolefin resin wall film comprising a polyolefin resin, a hindered amine compound, a hydrotalcite compound and a UV absorber, which is preferably used to form the walls of greenhouses or tunnels used in protected horticulture in which soils and / or plants

  are treated with an inorganic sulfur agent.

  In a second aspect, the present invention provides a method for treating soils and / or plants with an inorganic sulfur agent in a greenhouse or

  tunnel for protected horticulture, the walls of which consist of the film

  above. In a third aspect, the present invention relates to a method for growing plants in greenhouses or tunnels for protected horticulture.

  whose walls are constituted by the film above.

  The 2,2,6,6-tetraalkylpiperidine derivatives which preferably have a molecular weight of at least 250 and which carry a substituent at the 4-position are preferred examples of hindered amine compounds which are used according to the present invention. The carboxyl, alkoxy and alkylamino groups are examples of substituents at the 4-position. The piperidine ring

  can carry an alkyl group on the nitrogen atom.

  The following compounds (1) to (22) are specific examples of hindered amine compounds:

0 0

} N i-OC- (CH 2) 8-CO-4 (1)

H3C-N OC- (CH2) 8 -CON-CH3 (2)

A 8 R O

H3C-N O-C-C-C-O-CH3 (3)

C 4H9

(R-CH 2? -OH)

CH2-COO-R

CH-COO-R

I R H (4)

CH-COO-R

CH2-COO-R

  HOCH CH COCH 2 CH - CH (5) OXNC222 22 2 2 \ Q H

ill i O Q

  N-CH2CH2-O-C-CH2CH2-C-O-CH2CH2 O-C-CH2CH2-C (6)

n N t XN - (- CH 2) N (7) N tN NH ii

C H N

N> T A (8)

L 37 H> HN n Ny D H H nl

HCA2 C LLH (9

CH3 CH3 CH3 H

2H CH3 C2H5 - 3

Hx H

CH OCO H -C-O-CH 9

CH X I l I 9 If C H

2 O /

C3 CH3 0 0 CH3 CH3

CH3

CH H3 CH

3 3 0 OC 4H9 CH3

z - x Il_1 / -

CH N C -C-O CH (10)

/ \ CH2

CH3 CH3 CH3 CH

(t) C H C H (t)

4 9 OH 4 9

CH CH CH CH

-C8 H17 (11) N (CH2-C-OH) 3 (14)

CHC H C3 C H3

CH3 H3

II

O-C-C 7H35 SO CH

17 35 (12) (15)

C H3 HCH3 CH03 H CH 3

0 0

he O-C-CH3 o-C-NH

(13) (16)

CH3 H3 CH3 CH3

CH H CH CH3 HCH3

3 33

-CH2 O = C- NH

O-CH2431 - CH

lHNXC0; 3 (20) CH3 tH.3 (17) CH3 H

CH3 N H

CH3H CH3 HH

CH3 CH3

3 3

0 O

i [l It o = c NH

C ----- / C 0 I (21)

C1 V == J1 (18) HN C =

CH 3, CH 3 CH H 3 CH 3 H 3

CH N CH CH N CH N

3 H CH3 3 H 3 CH3 H CH3

R-NH- (CH2) 3N (CH2) 2-N- (CH2) 3-NH-R

R R

CH

CH (22)

(19) H3

(H X _0 - P C4H9 CH3

R = H or N H

3 CH3 N CH

N -N CH3 3

3- CH3

CH 3

C4H H3

  Preferably, the amount of hindered amine compound is at least 0.02% by weight, more preferably at least 0.1% by weight based on the total weight of the polyolefin resin film, from the point of view of the resistance of the film to bad weather. From the point of view of the appearance of the film and the suppression of temper, the amount of hindered amine compound is preferably less than or equal to 5% by weight, more preferably

  less than or equal to 2% by mass.

  The hindered amino compounds can be used

  independently or in a mixture of two or more of them.

  Of the hindered amine compounds listed below,

  above, the compounds of the formulas (6), (7) and (8) are preferred with regard to the

  weather resistance and the appearance of the film obtained.

  The hydrotalcite-type compound is, for example, a compound corresponding to formula (I): M1-x Alx (OH) 2 (An-) x / n.mH2O (1) in which M2 + is a divalent ion of a chosen metal in the group consisting of magnesium, calcium and zinc, x is a number greater than 0 and less than

  0.5, m is a number between 0 and 2 and An- is an n-valent anion.

  The n-valent anion is not limited and preferred examples of this anion are Cl-, Br-, 1-, NO3-, ClO4-, SO42-, Co32-, SiO32-, HPO43-, HB043, PO43-. , Fe (CN) 43-, Fe (CN) 44-, CH3COO-, C6H4 (OH) COO-, (COO) 2-, the terephthalate ion and the naphthalenesulfonate ion, etc. Natural hydrotalcite (Mgo, 75Al0.25 (OH) 2 (CO3) 0.125.0.5H2O), and synthetic hydrotalcite (Mg0 69AlO.31 (OH) 2 (CO3) 0.15.0.54H20 are specific examples of For example, the DHT-4A registered product manufactured by KYOWA Chemical Industries, preferably the amount of hydrotalcite-type compound is at least 0.1% by weight, more preferably at least 0.1% by weight. at least 1% by weight, relative to the total mass of the film in terms of improving the resistance of this film to the weather.As regards the transparency and the mechanical strength of the film, the amount of hydrotalcite-type compound is preferably 25% by weight or

  less, more preferably 10% by mass or less.

  The average particle size of the hydrotalcite compound is preferably 5 μm or less, more preferably 0.05 to 2 μm,

  regarding the transparency of the film.

  The hydrotalcite-like compound may be surface-treated with a higher fatty acid or an alkaline salt of a higher fatty acid to improve its

dispersibility in the resin.

  The UV absorbers of the benzophenone, benzotriazole, benzoate and cyanoacrylate type are examples of UV absorbing agents which are

can use.

  The following compounds of formulas (23) to (31) are specific examples of such UV absorbers:

HO O HO

(1'.N (23) OI C 3 (28)

t -C8Hl?

HO 0 HO

(24) (29)

0CE3 OC8 H 17

(25) Cc c (30) 'lq = (30) c c

COOC2P5

} i t -CsH5ll t -C5H.l (HOO

: 1 N} 1 _.

Fucked (27)

CH3

  The amount of UV absorbing agent is at least 0.01% by weight, more preferably at least 0.05% by weight relative to the total weight of the

  film, from the angle of improving the weather resistance of the film.

  As regards the appearance of the film, in particular the suppression of tarnishing, the UV absorbing agent is preferably present in an amount of 3% by weight or

  less, more preferably 1% by mass or less.

  UV absorbing agents can be used independently or

  in a mixture of two or more of them.

  The polyolefin resins which may be used according to the present invention are, for example, homopolymers of ethylene and of anolefin having 3 to 10 carbon atoms (for example polyethylene, polypropylene), copolymers of ethylene and of an act olefin having 3 to 10 carbon atoms (per

  example ethylene-propylene copolymers, ethylene-but-1-ene, ethylene-4-

  methylpent-1-ene, ethylene-hexene, ethylene-octene), copolymers comprising ethylene and other monomers having a polar vinyl group (for example ethylene-vinyl acetate copolymers, ethyleneacide acrylic, ethylene-methyl methacrylate , ethylene-vinyl acetate-methacrylate

methyl, ionomer resins).

  Of these resins, polyethylene is preferred, particularly low density polyethylene having a density of 0.93 g / cm 3 or less, ethylene-α-olefin copolymers and ethylene-vinyl acetate copolymers containing 30% by mass or less because they have excellent transparency and flexibility and can produce

inexpensive movies.

  The thickness of the polyolefin resin film according to the present invention is preferably at least 0.02 mm from the point of view of the mechanical strength of the film. As regards the possibilities of assembly and application of the film, its thickness is preferably 0.3 mm or less. More preferably, its

  thickness is between 0.03 and 0.2 mm.

  The polyolefin resin of the wall film may contain one or more additives such as an anti-adhesion agent, a heat stabilizer, a weathering agent, a filler, an anti-tarnish agent, a lubricant, a colorant, etc. provided that these additives are not detrimental

  to the objects according to the present invention.

  The anti-adhesion agent is added to the polyolefin resin to prevent the phenomenon whereby the transparency of the film is degraded by the fact that the inner surface of the film is covered with fine droplets of water of condensation, and the agents of this type include solid agents and liquid agents at room temperature (23C). The solid antiadhesive agents are, for example, nonionic surfactants such as fatty acid esters of sorbitan (for example sorbitan monostearate, sorbitan monopalmitate, sorbitan monobhenate), fatty acid esters of glycerol (for example glycerol monolaurate, glycerol monopalmitate, glycerol monostearate, diglycerol distearate, triglycerol monostearate), polyethylene glycol-based surfactants (eg, polyethylene glycol monopalmitate, polyethylene glycol monostearate), alkylphenol adducts, and alkylene oxides, organic acid esters and sorbitan / glycerol condensates. The liquid anti-adhesion agents are, for example, fatty acid esters of glycerol (for example glycerol monooleate, diglycerol monooleate, diglyceryl sesquioleate, tetraglycerol monooleate, hexaglycerol monooleate, glycerol pentaoleate, diglycerol pentaoleate, pentaoleate). tetraglycerol, hexaglycerol pentaoleate, tetraglycerol monolaurate, hexaglycerol monolaurate), esters of fatty acids and sorbitan (e.g.

  sorbitan monooleate, sorbitan dioleate, sorbitan pentaoleate, etc.).

  The anti-tarnishing agents are, for example, fluorinated compounds having a perfluoroalkyl group, an o-hydrofluoroalkyl group, in particular fluorinated surfactants, silicon compounds having an alkylsiloxane group,

  in particular surfactants containing silicon.

  The thermal stabilizers are, for example, hindered phenolic compounds (for example 2,6-dialkylphenyl derivatives, 2-alkylphenol derivatives, etc.), sulfur compounds having a thiol bond or a thioether bond involving a sulfur atom. divalent, phosphites

  having a trivalent phosphorus atom.

  Nickel compounds are examples of weathering agents. The fillers are for example constituted by magnesium oxide, calcium oxide, aluminum oxide, silicon oxide, titanium oxide, lithium hydroxide, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, potassium sulphate, magnesium sulphate, calcium sulphate, zinc sulphate, aluminum sulphate, lithium phosphate, sodium phosphate, potassium phosphate, calcium phosphate, magnesium silicate, calcium silicate, aluminum silicate, titanium silicate, sodium aluminate, sodium aluminate potassium aluminate, calcium aluminate, sodium aluminosilicate, potassium aluminosilicate, calcium aluminosilicate, kaolin,

talc and clay.

  The polyolefin resin wall film according to the present invention may be a monolayer film or a multilayer film having two or more laminated layers. In the case of the multilayer film, each layer may comprise the polyolefin resin and at least one of the hindered amine compound, the hydrotalcite type compound and the UV absorbing agent. Resins and additives can be the same or different

in the different layers.

  A multilayer film consisting of a three-layer structure of three different types or a three-layer structure is preferably used.

layers of two different types.

  The outer-facing layer of the greenhouse or tunnel may be subjected to a dust-proofing treatment while the inner-facing layer

  may be subjected to anti-adhesion treatment and / or anti-

  temrnissement. The inner layer may contain a thermal insulation comprising

for example an inorganic filler.

  To impart the anti-adhesive properties, an anti-adhesive coating

  tempering (anti-adhesion coating), which is added to the anti-adhesion agent

  which is incorporated in the resin, can be formed at least on the layer

  turned towards the inside of the greenhouse or tunnel.

  The anti-blocking coating may be for example a coating film consisting of an inorganic oxide sol such as colloidal silica and colloidal alumina such as that described in Japanese Patent Publication Nos. 32668/1974 and 11348/1975. a coating film constituted by a mixture of such an inorganic oxide sol and an organic compound (for example a surfactant or a resin) such as those described in Japanese Patent Publication No. 45432/1988, 45717/1988 and 2158/1989 and in Japanese Unexamined Patent Application Kokai No. 207643/1991, a coating film formed from a liquid comprising a surfactant, a film of a hydrophilic resin (for example poly ( vinyl alcohol), polysaccharides, poly (acid

acrylic, etc.).

  The anti-blocking coating may be formed by applying or laminating a separately formed film to the polyolefin laminate film. The coating application process is not critical and it is possible to form

  two or more anti-tarnish coatings.

  The polyolefin resin film according to the present invention can be produced as follows: Specific amounts of hindered amine compound, hydrotalcite compound, UV absorbing agent and optional additives such as antiadhesive agent the thermal stabilizer, the weathering agent, is incorporated in the polyolefin resin by means of a conventional mixing and kneading apparatus such as a belt mixer, a super mixer, a Banburv mixer or an extruder. screw or two screws. The mixture is then used by a conventional method such as extrusion

  T-die or extrusion-inflation to obtain a film.

  The film according to the present invention is preferably used for

  form the walls of a greenhouse or tunnel used in protected horticulture.

  When an inner curtain is provided in the greenhouse or tunnel, it may be

  formed by the polyolefin resin film of the present invention.

  Sulphocalcium slurry, sulfur flower, hydrated sulphurants, sulfur fumigants, and lime and sulfur aerosols are examples of inorganic sulfur compounds that are used primarily as bactericides or insecticides to treat soil. and / or plants, as described in the document "AGROCHEMICAL HANDBOOK-1985" edited by AGROCHEMICAL HANDBOOK- 1985 EDITORIAL COMMIITEE (published by NIPPON SHOKUBUTSU BOUEKI KYOKAI in 1985. According to this document, it is assumed that, when used As inorganic sulphidic agents, as bactericides, they form fine particles of sulfur which act as a bactericidal constituent, and their functional mechanism is based on blocking the electron transfer system of a pathogenic fungus by sulfur, so that the synthesis of ATP in the fungus is inhibited resulting in death of the fungus.The use of sulfur-containing agents as a bactericide is published in France in 1851 in the form of sulphocalcium porridge. As a spectrum of action, they have bactericidal effects on rust and mildew and insecticidal effects on mites and insects. They are often applied to fruit trees such as apple trees, persimmon trees, walnut trees, pear trees, peach trees, grapevines, orange trees and also strawberries, melons, watermelons, vegetables such as mushrooms. cucumbers, hops, wheat, roses, chrysanthemums, weights, tea, pine, blackberries, turf. This document describes their applications and methods of use in more detail. In the present invention, the treatment of soils and / or plants with an inorganic sulfuric agent means the spraying of the inorganic sulfur agent at least once in a greenhouse or tunnel for protected horticulture whose walls are constituted by the film in question. polyolefin resin according to the present invention. The inorganic sulfuric agent can be sprayed before or after the start of plant cultivation. The inorganic sulfuric agent may be applied in a process and in amounts identical to those conventionally employed. A typical process and quantity are described in

document cited above.

  According to the present invention, the method for cultivating greenhouse or tunnel plants for protected horticulture comprises treating the soil and / or plants with the inorganic sulfur agent at least once in the greenhouse or tunnel for protected horticulture whose walls are constituted by the resin film of

  polyolefin according to the present invention.

  The inorganic sulfuric agent includes sulfur and is used to

  reduce the number of sprays of organic agrochemicals.

  In particular, the sulfur fumigation by electric heating is very effective to reduce the amount of organic agrochemicals used in the cultivation of roses (mildew or mites), strawberries (mildew, mites or gray rust), chrysanthemums (white rust) . In addition, the sulphocalcic slurry is preferably used for the cultivation of fruit trees such as the

  persimmon, the vine, the orange tree, for example.

  When the polyolefin resin film according to the present invention is used as a material for the walls of a greenhouse or tunnel for the cultivation of plants, it does not suffer from the deterioration of the weather resistance which is normally caused by Inorganic sulfuric agents that are sprayed in the greenhouse or tunnel to treat the soil and / or plants, so that it is possible to reduce the amounts of organic agrochemicals used in the process.

greenhouse or tunnel.

  In arboriculture, if the film is broken as a result of deterioration during important periods of growth such as the fruit formation period, there is a very serious problem because the fruit trees are perennial plants. When the polyolefin resin film according to the present invention is used, the plants can be stably grown for a long time. In addition, the present invention allows the cultivation of strawberries, melons, watermelons, cucumbers, roses, potted flowers, ferns, for example by reducing the amount of organic agrochemicals through

  Sulfur fumigation by electric heating.

  In addition, the film according to the present invention can be used as

malting film.

  We will give in the following non-limiting examples intended to

  describe the present invention in more detail.

  The atmospheric resistance test was carried out as follows: A test specimen of JIS 1 dumbbell film was immersed for 24 hours in a sulphocalcium slurry (27.5% aqueous solution of calcium polysulphide). from HOKKO Chemical Industries) which was diluted with seven times its volume of water, after which the test piece was washed with water and dried. The specimen was aged in a Sunshine Weather-O-meter (manufactured by SUGA TEST INSTRUMENTS) at a

  black panel temperature of 63C for different durations.

  Then, the specimen was subjected to a tensile test to measure the elongation (%), and the duration of the atmospheric resistance test for which the elongation was reduced to half the elongation of the specimen. specimen before aging (half-life or period of resistance to atmospheric agents) was noted. A long period reflects a good resistance to atmospheric agents. In this test, a period or half-life of resistance to

  1000 h atmospheric agents is an acceptable threshold.

  The elongation (%) was calculated according to the following formula:

  Elongation (%) = [(distance between reference marks (mm) at break-up-

  distance between the reference marks (mm) before the tensile test) x 100] / (distance between the reference marks (mm) before the tensile test) Example 1 To an ethylene-vinyl acetate copolymer (trade mark EVATATE H 2020, manufactured by Sumitomo Chemical Co., vinyl acetate content: 15% by weight), 0.6% by weight of a hindered amine compound (A) was added (trade name: TINUVIN 622-LD manufactured by Ciba-Geigy), 8.0% by weight of a hydrotalcite-type compound (registered trademark: DHT 4A manufactured by KYOWA Chemical Industries), 0.1% by weight of a UV absorbing agent (deposited: SUMISORB 130 manufactured by Sumitomo Chemical Co.), 0.1% by weight of an antioxidant (R) (registered trademark: IRGANOX 1010 manufactured by Ciba-Geigy), 1.4 % by mass of monoglycerol monostearate and 0.6% by weight of diglycerol distearate as anti-quenching agents and 0.2% by weight of stearic acid amide as a lubricant (mass percentages being based on the total resin composition) and then kneaded using a Banbury mixer at 130 ° C. for 5 minutes. Then, the mixture was pelletized with a pelletizer to obtain pellets of the composition. This composition is called

"resin composition (1)".

  Separately, to an ethylene-vinyl acetate copolymer (trade name: EVATATE D 2011 manufactured by Sumitomo Chemical Co., vinyl acetate content: 5% by weight), was added 0.6% by weight of amine compound hindered (A), 0.1% by weight of UV absorbing agent (trade name: SUMISORB 130 manufactured by Sumitomo Chemical Co.), 0.1% by weight of antioxidant (R), 1, 4% by weight of monoglycerol monostearate and 0.6% by weight of diglycerol distearate as anti-tarnish agents, and 0.2% by weight of stearic acid amide as a lubricant (the percentages of mass being based on the total resin composition) and then kneaded using a Banbury mixer at 130 ° C. for min. Then, the mixture was pelleted by means of a pelletizer to obtain pellets of the composition. This composition is

  called "resin composition (2)".

  By using the resin composition (1) as an intermediate layer composition and the resin composition (2) as an outer layer composition, a laminated film comprising a 60 μm thick interlayer and outer layers each 20 nm thick (total thickness 100 μm) using an extrusion-inflation machine and the film obtained was subjected to the atmospheric resistance test. The

  The results, presented in the following table, are excellent.

  Examples 2, 3 and 4 A laminated film was produced in the same manner as in Example 1, except that the composition was modified as shown in the table, and the resulting film was subjected to the atmospheric resistance test. The results, presented in the table, are excellent for these

three examples.

Example 5

  A laminated film was produced in the same manner as in Example 1, except that 0.1% by weight of a surfactant was added to each of the resin compositions (1) and (2). fluorine (trademark: UNIDAIN DS 403 manufactured by DAIKIN Industries) and submitted

  film obtained in the atmospheric resistance test. The period or half

  The atmospheric resistance life was greater than 1000 h. Comparative Examples 1 to 4 A laminated film was produced in the same manner as in Example 1, except that the composition was modified as shown in the table, and the resulting film was subjected to atmospheric resistance test. The results, which were mediocre for all the examples

  Comparatives 1 to 4 are shown in the table.

  When the specimens have not been immersed in the aqueous solution of sulphocalcium slurry, their periods of resistance to atmospheric agents

  were greater than 1000 h, except in Comparative Example 3.

Example 6

  In a greenhouse whose long side was turned to the south and whose walls were made of the polyolefin resin film of Example 1, grapes (DELAWARE) were cultivated from February to August 1994 in Shimane prefecture, Japan. by spraying a sulfocalcic slurry solution (diluted with 20 times its volume of water) once in February in an amount of 100 liters per 991.7 square meters. In August, specimens were taken from the south facing wall film and subjected to a tensile test in the same manner as in the atmospheric resistance test. Tensile strength and elongation rates were found to be

  greater than 90%, and no deterioration was observed.

  Comparative Example 5 The same test as in Example 5 was carried out except that the film of Comparative Example 1 was used. The film broke at

  contact with the frame of the greenhouse.

Example 7

  In a greenhouse whose long side was oriented to the south and whose wall was formed by the polyolefin resin film of Example 1, strawberries (TOYONOKA) were cultivated from October 1993 to May 1994 in the prefecture of Gifu , Japan, carrying out fumigations of sulfur-containing agent (registered trademark: SHIN KONADEN manufactured by the company TOKAI BUSSAN) by electric heating in the following manner: A fumigation apparatus was provided for 100 m3 of greenhouse and fumigation was carried out of the sulfur agent for 8 hours each day. The total quantity

  sulfur fumigant used was 50 g for two months.

  In the period above, mildew, gray rust and mites

have been completely avoided.

  In May, samples were taken of the south wall wall film and these samples were subjected to the tensile test in the same manner as in the atmospheric resistance test. Both the tensile strength and elongation maintenance rates were

  greater than 90% and no deterioration was observed.

  Comparative Example 6 The same test as in Example 6 was carried out except that the film of Comparative Example 1 was used.

  Both traction and elongation were about 40%.

Board

  Ex. N Intermediate layer Outer layers Amine-to-hindered Amines Half-life of steric agent Steric agent Resistance agent Absorbing AB resin Absorbent AB resin Compound to agents (type)% in% in inorganic UV (type)% in% in Inorganic UV atmospheric mass mass (% by mass) (mass%) mass mass (mass%) (mass%) (h) 1 a (0.60 --- X ((0.1 () A (8) , 0) b 0 (, 60 --- X (0.1 ()) ---> 1000 2 c 0.60) Y (0.07) A (8, () c 0.60 - Y (0) , 07) A (2.0)> 1) 000 3 to 0.35 0.45 _ A (3, 0) d 0.35 0.45 X (0.30) A (3.0)> 1000) 4 b 0.35 0.45 X (0.20) A (3.0) h 0.35 0.45 X (0.20) A (3.0)> 1000 C. 1 to 0.60 - - - A (8.0 () b 0.60 --- --- --- 700 C.2 to 0.60 - X (0.10) ___ b 0), 60 --- X (0, 10) - 450 C.3 a --- --- Y (0.10) A (8.0) b --- --- Y (0.10)) A (2.0) <300 ° C .4 b 0.35 0.45 X (0), 20) B (3,)) b 0.35 0.45 X (0.20) B (3, 0) 500 Remarks Resin to: EVATATE H2020 (copolymer ethylene vinyl acetate manufactured by Sumitomo Chemical Co., vinyl acetate content

% by mass).

* Resin b: EVATATE D2011 (ethylene-vinyl acetate copolymer manufactured by Sumitomo Chemical Co., vinyl acetate content 5%

in mass).

  Resin c: SUMIKATHENE F208-0 (low density polyethylene manufactured by the

Sumitomo Chemical Co.).

  Resin d: SUMIKATHENE L FA201-0 (linear low density polyethylene (ethylene-but-1-ene copolymer) manufactured by Sumitomo

Chemical Co.).

  Hindered amine A: TINUVIN 622-LD (manufactured by Ciba-Geigy). B: CHIMASORB 944-LD (manufactured by

Ciba-Geigy company).

  UV absorbing agent X: SUMISORB 130 (hydroxybenzophenone type UV absorbing agent manufactured by the company

Sumitomo Chemical Co.).

  UV absorbing agent Y: SUMISORB 300 (hydroxybenzotriazole type UV absorbing agent manufactured by the company

Sumitomo Chemical Co.).

  Inorganic Compound A: DHT-4A (synthetic hydrotalcite manufactured by the

  KYOWA Chemical Industries).

  Inorganic Compound B: SNOW MARK SP-10 (Crushed Natural Silica)

  made by KINSEI MATEC).

  Reference Example 1 To an ethylene-vinyl acetate copolymer (registered trademark EVATATE H 2020 manufactured by Sumitomo Chemical Co., vinyl acetate content: 15% by weight), 0.3% by weight of compound was added. hindered amine (A) (trade name: TINUVIN 622-LD manufactured by Ciba-Geigy), 3.0% by weight of hydrotalcite-type compound (trade name: DHT 4A manufactured by KYOWA Chemical Industries), 0.1% by weight of UV absorbing agent (trade name: SUMISORB 130 manufactured by Sumitomo Chemical Co.), 0.1% by weight of antioxidant (R) (registered trademark: IRGANOX 1010 manufactured by Ciba company -Geigy), 1.4% by weight of monoglycerol monostearate and 0.6% by weight of diglycerol distearate as anti-quenching agents and 0.2% by weight of stearic acid amide as lubricant (the mass percentages being based on the total resin composition) and kneaded the mixture obtained in a Banbury mixer at C for 5 min. The mixture was then pelletized with a pelletizer to obtain pellets of the composition. This composition is called

"resin composition (a)".

  Separately, to an ethylene-vinyl acetate copolymer (trade name: EVATATE D 2011 manufactured by Sumitomo Chemical Co., vinyl acetate content: 5% by weight), was added 0.3% by weight of amine compound hindered (A), 0.1% by weight of UV absorbing agent (trade name: SUMISORB 130 manufactured by Sumitomo Chemical Co.), 0.1% by weight of antioxidant (R), 1, 4% by weight of monoglycerol monostearate and 0.6% by weight of diglycerol distearate as anti-quenching agents, and 0.2% by weight of stearic acid amide as a lubricant (the percentages of mass being based on the total resin composition) and the resulting mixture was kneaded in a Banbury mixer at 130 ° C. for 5 minutes. The mixture was then pelletized with a pelletizer to obtain pellets of the composition. This composition is called

"resin composition (b)".

  By using the resin composition (a) as an intermediate layer composition and the resin composition (b) as the outer layer composition, a laminated film comprising a 60 μm thick interlayer and layers was formed. outer layers each 20 μm thick (100 μm total thickness) by means of an extrusion-inflation machine, and the film obtained was subjected to the atmospheric resistance test without immersing the film in the reaction solution. sulphocalcic porridge. The half-life of resistance to atmospheric agents was 950 h. Reference Example 2 A laminated film was produced in the same manner as in Reference Example 1, except that no UV absorbing agent was used, and this film was subjected to atmospheric resistance test without immersing it in the sulphocalcic slurry solution. The period of resistance to atmospheric agents was 900 h. As shown by the results of Reference Examples 1 and 2, when the films were not exposed to the inorganic sulfur agent, the atmospheric resistance was substantially the same in the presence or absence

UV absorbing agent.

  Comparing Example 1 and Comparative Examples, it is found that the UV absorbing agent has a significant effect on the maintenance of atmospheric resistance when the films have been exposed to the inorganic sulfur agent.

Claims (14)

  A polyolefin resin wall film, characterized in that it comprises a polyolefin resin, a hindered amine compound, a hydrotalcite compound and a UV absorbing agent and in that it is used to form the walls of a greenhouse or tunnel in protected horticulture   with treatment of the soil and / or plants with an inorganic sulfur agent.   Film according to claim 1, characterized in that the amount of said hindered amine compound is 0.02 to 5% by weight, the amount of said hydrotalcite-type compound is 0.1 to 25% by weight and the the amount of said UV absorbing agent is 0.01 to 3% by weight based on the total mass of the film. 3. Film according to claim 1, characterized in that it has a   multilayer structure comprising at least two layers.   4. Film according to claim 3, characterized in that it comprises three layers. Film according to claim 2 or 3, characterized in that said polyolefin resin is constituted by at least one resin selected from the group consisting of polyethylene, ethylene-act-olefin copolymers and   ethylene-vinyl acetate copolymers.   Film according to claim 5, characterized in that said polyolefin resin is a low density polyethylene having a density of 0.93 g / cm3 or less. 7. Film according to claim 1, characterized in that said inorganic sulfuric agent is constituted by at least one agent selected from the group consisting of the sulphocalcic slurry, the sulfur flower, a hydrated sulfur agent, an agent   fumigated sulfur and an aerosol of lime and sulfur.   8. Process for treating soils and / or plants with an inorganic sulfur agent in a greenhouse or tunnel for protected horticulture whose walls are constituted by a film of polyolefin resin, characterized in that said   film is a film according to any one of claims 1 to 7.   9. A method for cultivating plants in a greenhouse or tunnel for protected horticulture whose walls are constituted by a film of polyolefin resin, characterized in that it comprises the treatment of the soil and / or plants at least once with a inorganic sulfuric agent and in that said film   is a film according to any one of claims 1 to 7.   10. The method of claim 9, characterized in that said plants are fruit trees.   11. The method of claim 9, characterized in that said plants are strawberries, melons, watermelons, cucumbers, roses or chrysanthemums.   12. Use of a film according to any one of claims 1 to   7, characterized in that said film is used to form the walls of a greenhouse or tunnel for protected horticulture with soil treatment and / or plants at   less once with an inorganic sulfur agent.   13. Use according to claim 12, characterized in that said   plants grown in said greenhouse or said tunnel are fruit trees.   14. The use according to claim 12, characterized in that said plants cultivated in said greenhouse or said tunnel are strawberry plants, melons,   watermelons, cucumbers, roses or chrysanthemums.