JPH07163247A - Soil-covering material - Google Patents

Abstract

PURPOSE:To obtain a soil-covering material having excellent weather resistance, composed of a laminated film, etc., having a specific porous polyolefin layer on a substrate and enabling the increase of sugar content and early maturation of fruit by stretching in a state to cover the soil of the part near the root of a fruit tree. CONSTITUTION:This soil-covering material is composed of a laminated film or sheet obtained by laminating a substrate with a porous polyolefin layer produced by forming a film or sheet from a resin composition composed of (A) 100 pts.wt. of a polyolefin resin having a density of <=0.965 g/cm<3> and a melt index of <=10g/10min, (B) 25-400 pts.wt. of a filler such as calcium carbonate surface-treated with a phosphoric acid ester, (C) 0.1-10 pts.wt. of a hindered amine light-stabilizer and (D) 0.1-10 pts.wt. of a benzotriazole, benzophenone or benzoatetype ultraviolet absorber and at least uniaxially drawing the film or sheet in the take-up direction of the film, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is intended to cover the soil at the base of fruit trees for the purpose of increasing the sugar content of fruits and early ripening in the cultivation of fruits such as mandarin oranges, peaches, apples, pears and grapes. The present invention relates to a moisture-permeable soil coating material for spreading, and particularly relates to a soil coating material having excellent weather resistance.

[0002]

2. Description of the Related Art Conventionally, at the time of cultivating fruits, the soil at the base of fruit trees has been covered with a shielding sheet for the purpose of increasing the sugar content of the fruits and accelerating the harvest time. If such a sheet does not have appropriate waterproofness, moisture permeability and breathability,
Heat accumulates on the lower surface of the sheet, which hinders the increase in sugar content of the fruit, and the moisture is not released, resulting in excessive humidity in the soil and root rot.

[0003]

One of the means for solving these problems is to use a material such as a non-woven fabric or the like on which a microporous film made of a thermoplastic resin is attached, as a soil covering material. However, the film had a problem in weather resistance.

[0004]

Therefore, the present inventors have found that a laminated film or sheet obtained by laminating a porous polyolefin layer formed of a resin composition subjected to a specific weathering treatment with a substrate is a soil-covered film. It has suitable moisture permeability and breathability as a material, has excellent weather resistance in long-term use, and is further resistant to scratching and the like in the bonding step with a base material, and has good strength, The present invention has been completed.

That is, the gist of the present invention is that (A) the density on the substrate is 0.965 g / cm ³ or less, and the melt index is 10 g.
100 parts by weight of a polyolefin resin of / 10 min or less,
(B) Filler 25-40 whose surface is treated with phosphate ester
0 parts by weight and (C) hindered amine light stabilizer 0.1
10 parts by weight and (D) a benzotriazole-based or benzophenone-based or benzoate-based UV absorber 0.1-
A soil coating material comprising a laminated film or sheet having a porous polyolefin layer obtained by uniaxially stretching a film or sheet obtained by forming a resin composition comprising 10 parts by weight in at least the taking direction thereof. Exist.

The present invention will be described in more detail below. The polyolefin resin (A) is a homopolymer of ethylene or propylene or a density (ρ) of a homopolymer of ethylene or propylene and a copolymer of ethylene or propylene and another comonomer (a compound having at least one double bond having 4 or more carbon atoms in the molecule).
965 g / cm ³ or less, melt index (MI) 1
Polyolefin thermoplastic resin of 0 g / 10 min (g / 10 minutes) or less, for example, high-density polyethylene, branched low-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, density 0.910 g / cm ³ or less Ultra low density polyethylene, polypropylene, ethylene-
Any of a propylene copolymer, an ethylene-propylene-diene copolymer, an ethylene-methacrylic acid ester or a mixture thereof may be used.

The linear low-density polyethylene is a copolymer of ethylene and another α-olefin, and is different from the branched low-density polyethylene produced by the conventional high pressure method. The linear low-density polyethylene is, for example, ethylene and about 4 to 17% by weight, preferably about 5 to 15% by weight, of other α-olefins such as butene / hexene, octene, decene, and 4-methylpentene-1. Is copolymerized with a Ziegler-type catalyst or Phillips-type catalyst used for producing medium- and low-pressure method high-density polyethylene. This is a conventional high-density polyethylene having a short branched structure with a copolymerization component, and the density is appropriately reduced by utilizing this short-chain branching to 0.91 to 0.95 g /
The polyethylene having a structure of about ³ cm ³ is more linear than conventional branched low-density polyethylene and more branched than high-density polyethylene. Branched low density polyethylene includes ethylene homopolymers and copolymers of ethylene with other copolymerization components. Examples of the copolymerization component include vinyl compounds such as vinyl acetate, ethyl acrylate and methyl acrylate, and olefins having 3 or more carbon atoms such as propylene, 4-methylpentene-1, hexene and octene. The copolymerization amount of the copolymerization component is 0.5 to 18% by weight, preferably about 2 to 10% by weight. It is preferable that these branched low-density polyethylenes are obtained by radical polymerization by a normal high-pressure method (1000 to 3000 kg / cm ² ) using a radical generator such as oxygen or organic peroxide. .

In the present invention, the melt index (M
I) is JIS which is a reference standard of JIS K 6760.
It is a value measured according to the condition 4 of Table 1 of K 7210. In addition, a heat stabilizer, a pigment, an antistatic agent, a fluorescent agent and the like may be added to the polyolefin resin according to a conventional method. Next, as the filler of the component (B), inorganic and organic fillers are used. As the inorganic filler, calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium sulfate, aluminum hydroxide, zinc oxide, magnesium hydroxide, calcium oxide,
Magnesium oxide, titanium oxide, alumina, mica, asbestos powder, glass powder, shirasu balloon, zeolite,
Silicate clay is used, especially calcium carbonate, talc,
Clay, silica, diatomaceous earth, barium sulfate and the like are preferable.

As the organic filler, cellulosic powder such as wood powder or pulp powder is used. These may be used alone or as a mixture. The average particle size of the filler is 30
Those having a size of not more than μm are preferable, those having a size of 10 μm or less are more preferable, and those having a thickness of 0.2-5 μm are most preferable. The feature of the present invention is that the surface of the filler is treated with phosphoric acid ester. As such a phosphoric acid ester, for example, those represented by the formula (1) are suitable.

[0010]

[Chemical 1] R: alkyl or alkylallyl group (C number is 1 to 3)
0) n: the number of moles of ethylene oxide added (the number of moles is 1 to 3)
0) R ': H or R (CH ₂ CH ₂ O) _n group

The surface treatment of the filler is carried out for the purpose of improving the dispersibility in the resin, the stretchability and the weather resistance, and reflecting the ultraviolet rays which are the causes of deterioration. The treatment amount is 0.5 to 10 parts by weight, preferably 0.5 to 5 parts by weight, and more preferably 1 to 3 parts by weight with respect to 100 parts by weight of the filler.

Component (C) a hindered amine light stabilizer,
Examples of the (D) benzotriazole-based or benzophenone-based or benzoate-based UV absorbers and (E) the metal salts of acidic phosphoric acid esters include various substances. Specifically, for example, (C) hindered amine light stabilizers include Sanol LS-770 and LS-262.
6, the same LS-765 (trade name, all manufactured by Sankyosha), T
inuvin 144, same 622, same 622LD, same 7
70, 120 (trade name, all manufactured by Ciba Geigy), Chimasorb 944FL, 944L
D, 119FL (trade name, all manufactured by Ciba Geigy), ADEKA STAB LA-57, LA-77, L
A-62, LA-67, LA-63, LA-6
8, the same LA-82, the same LA-87 (trade name, all manufactured by Asahi Denka Co., Ltd.), Sumisorb TM-061 (trade name, manufactured by Sumitomo Chemical Co., Ltd.), Cyasorb UV-33.
46 (trade name, manufactured by ACC), Goodrite UV
-3034 (trade name, manufactured by Goodrich Co.) and the like can be mentioned.

Examples of the (D) benzotriazole type ultraviolet absorber include 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,
5-bis (α, α-dimethylbenzyl) phenyl] -2
H-benzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenyl) benzotriazole, 2
-(3-t-Butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5
-Di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole, 2
-(2'-hydroxy-5'-t-octylphenyl)
Examples thereof include benzotriazole.

As the benzophenone type ultraviolet absorber,
2-hydroxy-4-n-octoxybenzophenone,
2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, p
-T-butylphenyl salicylate-2-hydroxy-
4-methoxybenzophenone, 2- (2-hydroxy-
3,5-di-t-butylphenyl) benzotriazole and the like.

As the benzoate type ultraviolet absorber,
2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate and the like can be mentioned. Examples of the metal salt of (E) acidic phosphate ester include stearyl acid phosphate, magnesium stearyl phosphate, aluminum stearyl phosphate, calcium stearyl phosphate, zinc stearyl phosphate, and barium stearyl phosphate.

Among them, hindered amine light stabilizers, particularly Tinuvin 622 and 622LD (dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate of dimethyl succinate). , Chimasorb 944FL, and 944LD
(Poly [{6- (1,1,3,3-tetramethylbutyl), amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4 -Piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}]), a benzophenone-based UV absorber, especially 2-hydroxy-4-n-
Octoxybenzophenone is preferred. Zinc stearyl phosphate is preferable as the metal salt of the acidic phosphoric acid ester.

Sufficient weather resistance can be imparted by using a hindered amine-based light stabilizer and a benzotriazole-based, benzophenone-based, or benzoate-based UV absorber, but by further using a metal salt of an acidic phosphoric acid ester, The weather resistance can be maintained for a longer period of time. In the present invention, when the following plasticizer (F) and radical generator (G) are used in combination, the strength of the porous film or sheet is improved, and scratches and the like are prevented in the step of laminating with the base material described below. Therefore, it is preferable.

The plasticizer of component (F) has a molecular weight of 100 or more, preferably 350 or more, particularly 350 to 1500, having an ester bond or an amide bond in the molecule, and a boiling point at atmospheric pressure of 200 ° C. or more, preferably 250. ℃ or more,
Particularly, a compound having a melting point of 250 to 700 ° C. and a melting point of 100 ° C. or lower, preferably 50 ° C. or lower, particularly −100 ° C. to 10 ° C.

For example, an ester of a carboxylic acid having 6 or more carbon atoms and an alcohol having 5 or more carbon atoms or an aliphatic amide having 10 to 25 carbon atoms which satisfies the above physical properties can be mentioned. Among them, an ester of an aromatic carboxylic acid and an aliphatic alcohol having 6 or more carbon atoms, preferably an aromatic dicarboxylic acid or an aromatic tricarboxylic acid and an ester of an aliphatic alcohol having 6 to 18 carbon atoms, particularly an aromatic dicarboxylic acid Carbon number 8
An ester with an aliphatic alcohol of -15 and an ester of an aromatic tricarboxylic acid with an aliphatic alcohol with 6-18 are suitable.

Specific examples of these compounds include, for example, stearic acid amide, oleic acid amide, triisodecyl trimellitate, trioctyl trimellitate, diisodecyl phthalate, dioctyl phthalate,
Examples include dipentaerythritol-2-ethyl-hexanoic acid ester. Most preferably, trioctyl trimellitate, diisodecyl phthalate, and dipentaerythritol-2-ethylhexanoate are used.

When the melting point is higher than 100 ° C., the effect of improving the tear strength by modification with a radical generator is small, and when the boiling point is lower than 200 ° C., smoke and foaming during molding process lower the molding / stretchability. Further, when the molecular weight is small, bleeding of the plasticizer from the film is rapid, which is not preferable.

Next, if necessary, the radical generator of the component (G) used in the present invention has a decomposition temperature of 130 to 300 ° C., preferably 160 to 260, which has a half-life of 1 minute.
Those in the range of ° C are preferable, for example, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-bis (t
-Butylperoxy) -3-hexyne, α, α'-bis (t-butylperoxyisopropyl) benzene, dibenzoyl peroxide, di-t-butyl peroxide-
Examples include peroxides such as 2,5-dimethylhexane-2,5-dihydroperoxide. Most preferably,
2,5-dimethyl-2,5-bis (t-butylperoxy) -3-hexyne can be mentioned.

In the present invention, the filler (B) is 25 to 400 with respect to 100 parts by weight of the polyolefin resin (A).
Parts by weight, preferably 100 to 300 parts by weight, especially 130
~ 250 parts by weight and additives (C), (D), (E)
0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, particularly 0.3 to 3 parts by weight are compounded. The ratio of the filler (B) is 1
If the amount is less than 00 parts by weight, the stretched film will not have sufficient pores and the degree of porosity will be low. On the other hand, if the proportion of the filler exceeds 400 parts by weight, the kneadability, dispersibility, film or sheet moldability will be poor, and the surface strength of the stretched product will be reduced.

If the proportion of the additives (C), (D) and (E) is less than 0.1 part by weight, the weather resistance after long-term use will be insufficient. On the other hand, if the proportion of the additives exceeds 10 parts by weight, bleeding after forming the film or sheet becomes excessive, which is not preferable, and the effect of improving durability is also small. The usage ratio of the hindered amine light stabilizer and the benzotriazole-based, benzophenone-based, or benzoate-based UV absorber is 1 to 50:50 to 1, preferably 1.
-10: 10 to 1 When the metal salt of acidic phosphoric acid ester is used, the usage ratio is 1 to 50:50 to 1, preferably 1 to 1 with respect to the hindered amine light stabilizer.
It is 0:10 to 1.

When the plasticizer (F) and the radical generator (G) component are used in combination, the plasticizer (F) is 1 to 100.
Parts by weight, preferably 2 to 50 parts by weight, particularly 2 to 30 parts by weight, and the radical generator (G) is 0.0001 to 0.1.
It is desirable to blend in a range of 0.005 to 0.07 part by weight, preferably 0.005 to 0.05 part by weight.

When the amount of the plasticizer (F) is less than 1 part by weight, the effect of improving the tear strength is not obtained, and when it is more than 100 parts by weight, the kneading property and the dispersibility are deteriorated and the film formability is lowered and the stretchability is secured. Can not. Radical generator (G) is 0.0001
Is selected from the range of 0.1 to 0.1 parts by weight. If it is less than this range, the tear strength cannot be improved by the synergistic effect with the plasticizer, and if it is more than this range, the melt index becomes too low. However, it is not preferable because film breakage is likely to occur during film formation, and roughening of the film surface occurs.

In the present invention, polyolefin resin (A), filler (B), additives (C), (D),
(E), plasticizer (F), and radical generator (G)
Usually, for example, by the following method I or II, they are mixed at the above-mentioned ratio, then kneaded and pelletized, and then inflation-molded to obtain an unstretched film. Method I: A polyolefin resin, a filler, additives, a plasticizer, and a radical generator are mixed and kneaded using a kneader such as an extruder or a Banbury mixer, then pelletized, and inflation molding is performed using the pellets. To do.

Method II: A large amount of radical generator 0.3-2% (3000-20000 pp) is added to a polyolefin resin.
m) is mixed and melt-kneaded into pellets at a temperature at which the radical generator hardly reacts with the polyolefin and at a temperature equal to or higher than the melting point of the polyolefin to prepare a master batch. A filler, additives, and a plasticizer are mixed, kneaded, and then pelletized, and inflation is formed using the pellets.

When the polyolefin resin is kneaded with the radical generator under heating (preferably at a temperature not lower than the half-life of the radical generator is 10 minutes) according to the method shown in I or II above, crosslinking by the radical generator is carried out. A reaction occurs, the polyolefin is intermolecularly coupled, a high molecular weight component is increased, and a modified polymer having a reduced melt index is obtained. This modified polymer is more likely to be oriented in the lateral direction during inflation molding as compared with the polymer before modification, and thus the film thus obtained is significantly improved in tensile strength and impact strength when stretched. .

Polyolefin resin, additives, plasticizer,
To mix the radical generator and the filler, a drum, a tumbler type mixer, a ribbon blender, a Henschel mixer, a super mixer or the like is used, but a high speed stirring type mixer such as a Henschel mixer is preferable, and polyethylene is Usually, it is preferable to supply in the form of powder having a particle size of 10 to 150 mesh, especially 20 to 60 mesh. The kneading of the obtained mixture is carried out using a known kneading device such as a screw extruder, a twin screw extruder, a mixing roll, a Banbury mixer, a twin screw type kneader.

In the present invention, the thickness of the composition obtained above is usually 10 to 10 by an inflation method or a T-die method.
200μ unstretched film or thickness 200-400μ
The unstretched sheet is molded, and then this unstretched film or sheet is stretched. Inflation molding is usually carried out with a blow-up ratio (BUR) of 2-8.

Preferably, the blow-up ratio is 3 to 6, and the height of the frost line is 5 to 2 of the diameter of the annular slit of the die.
It is carried out under the condition of a range of 0 times. If the blow-up ratio is lower than the above range, the tensile strength and impact strength of the film are lowered, and if it is higher than the above range, the bubble molding stability is lowered. Further, if the height of the frost line is lower than the above range, the tensile strength of the film is lowered, and if it is higher than the above range, the bubble molding stability is lowered, so that the above range is preferable.

The unstretched film or sheet formed by the inflation method is then uniaxially stretched in the machine direction (the film take-up direction). The roll stretching method is usually employed for the uniaxial stretching, but the uniaxial direction (the take-up direction) may be emphasized by the tubular stretching method.
Further, the stretching treatment may be performed in one stage or in multiple stages of two or more stages. The product formed by the T-die method is subjected to longitudinal uniaxial stretching or biaxial stretching.

The stretching treatment is performed at 100 ° C. from the melting point of the resin composition.
It is preferable to carry out in the range of a low temperature to a temperature 20 ° C lower than the melting point, particularly a temperature of 90 ° C lower than the melting point of the resin composition to a temperature 50 ° C lower than the melting point. Occurrence occurs, and at temperatures higher than this range, the porosity of the film tends to decrease.

The draw ratio is preferably 1.2 to 8 times. It should be noted that heat treatment after stretching can stabilize the dimensional accuracy of the film, and surface treatment such as known corona treatment and flame treatment can be performed. The thus obtained porous film or sheet constituting the porous polyolefin layer of the present invention has high surface strength and tear strength and has no stretching unevenness, and therefore can be suitably used. Especially, the thickness is 1
In the case of a porous film having a thickness of 00 μ or less, for example, 15 to 50 μ, the bending resistance in both the longitudinal direction and the lateral direction is 50 mm or less, preferably 10 to 35 mm, and the water vapor transmission rate is 1500 g / m ^3.
・ 24 hours or more, preferably 2500 to 5000 g / m
Air permeability of 3000sec / 100cc at ³ / 24hr
Or less, preferably 2000 sec / 100 cc or less,
The surface strength is the following formula (2)

[0036]

## EQU00001 ## Surface strength [kg] .gtoreq.35.times.film thickness [mm] (2) Preferably, formula (2 '),

[0037]

## EQU00002 ## Surface strength [kg] .gtoreq.50.times.film thickness [mm] (2 ') is satisfied, and tear strength is expressed by the following formula (3).

[0038]

## EQU00003 ## Tear strength [g / sheet] .gtoreq.1500.times.film thickness [mm] (3) Preferably, formula (3 '),

[0039]

## EQU00004 ## A film satisfying the tear strength [g / sheet] .gtoreq.1800.times.film thickness [mm] (3 ') is obtained, which is preferable. As the base material for providing the above-mentioned porous polyolefin layer,
Any material may be used as long as it has air permeability so as not to impair the physical properties of the porous film or sheet, and may be, for example, paper, a split cloth made of split yarn, or a non-woven fabric, a woven fabric,
A net-like material having a basis weight of about 10 to 30 g / m ² is preferably used.

The porous polyolefin layer and the base material are laminated through an adhesive layer or by thermocompression bonding.
Usually, the adhesive layer or the thermocompression bonding part is partially provided between the porous polyolefin layer and the substrate. Specifically, for example,
There is a method in which the above porous film or sheet and a substrate such as paper or non-woven fabric are attached to each other with a hot melt adhesive or the like. At this time, the adhesive is partially provided, but it can be arbitrarily performed such as staggered spotting or line attachment at appropriate intervals.

Other bonding methods include a method of partially thermocompressing a porous film or sheet and a polyolefin split cloth or non-woven fabric, and a method of partially laminating the porous film or sheet and a substrate with a layer of low density polyethylene or the like. A method such as extrusion laminating through the method can be used. The thus obtained laminated film or sheet of the present invention has good mechanical strength and can be industrially advantageously produced. Also, since it is waterproof, and has good moisture permeability and air permeability, this laminated film or sheet can be spread as a multi-sheet on the soil at the root of the fruit tree to increase the sugar content of the fruit and accelerate the growth and harvest. It can be done, and because the heat and moisture of the bottom surface of the seat are released well, there is no root rot.

[0042]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to these examples without departing from the gist thereof. Example 1 (1) Linear low density polyethylene {melt index (MI): 1.0 g / 10 minutes, flow ratio: 19, density (ρ): 0.921 g / cm ³ , copolymerization component: 1-butene, 80 parts by weight of a product obtained by pulverizing a copolymerization amount: 10% by weight, melting point: 120 ° C.} into a powder of 40 mesh and low density polyethylene of high pressure method (MI = 2.0 g / 10 min, density 0.924 g / cm ³ 20 parts by weight of (1) was stirred and mixed in a Henschel mixer to obtain a polyolefin resin.

Next, 2.5 parts by weight of a hindered amine light stabilizer (trade name: TINUVIN 622LD, manufactured by Ciba Geigy) and an ultraviolet absorber (trade name: CYAO) were added.
RBUV-531, manufactured by American Cyanamid)
1.8 parts by weight of metal salt of acidic phosphoric acid ester (trade name: LBT-1830, manufactured by Sakai Chemical Industry Co., Ltd.)
Parts by weight, 10 parts by weight of dipentaerythritol-2-ethylhexanoate, 2,5-dimethyl-2,5-
Bis- (t-butylperoxy) -3-hexyne was added to 0.
02 parts by weight were added and mixed with stirring.

Further, 170 parts by weight of calcium carbonate surface-treated with phosphoric acid ester (Plysurf A208B 2% treated by Daiichi Kogyo Seiyaku Co., Ltd.) was added and mixed with stirring. The mixture thus obtained was mixed with a twin-screw kneader DSM-
65 (Double Screw Mixer, manufactured by Japan Steel Works, Ltd.) was kneaded and granulated. 40 this
Inflation molding with mmφ extruder, thickness 70
A film having a thickness of μm was formed. The extrusion conditions are as follows.

[0045]

[Table 1] Cylinder temperature: 170-190-210-2
30 ° C. Head, die temperature: 200 ° C. Die diameter: 100 mm Pulling speed: 8 m / min Blow-up ratio: 3 Frost line height: 700 mm Folding diameter: 471 mm

The film thus obtained was slit in the take-up direction and uniaxially stretched by a roll stretching machine.
The stretching conditions were as follows.

[Table 2] Stretching temperature: 60 ° C. Stretching ratio: 2.0 times Speed after stretching: 11.0 m / min Film thickness after stretching: 35 μm

The physical properties of the obtained film were evaluated as follows, and the results are shown in Table 1. 1) Water vapor transmission rate: According to ASTM E26-66 (E). 2) Tear strength: According to JIS P 8116, the pulling direction of the film is measured, and the strength per sheet is determined by g.

3) Surface strength: Film sample 100 m
Cut into squares of mx 100 mm, and have an inner diameter of 80 mm 2.
It is fixed by sandwiching it with a sheet of donut holding ring. A round bar with a thickness of 20 mm in the center of the film, with a radius of 10 m at the tip
A hemispherical plunger of m is pushed at a speed of 500 mm / min, the pressing distance when the film is broken is the elongation, and the strength at that time is the surface strength.

4) Formability: It was judged visually by the following criteria. ◎: Bubble stable, no die line ○: Bubble stable, die line △: Film width variation ×: Unmoldable

5) Stretchability ⊚: No cutting, uniform stretching, no stretching unevenness ○: No cutting, stretching unevenness, almost no Δ: No cutting, stretching unevenness, slightly ×: Cutting or stretching unevenness is large

(2) A nylon spunbonded nonwoven fabric (unit weight: 15 g / m ² ) is used as a substrate, and the hot melt resin is applied in a staggered manner on the nonwoven fabric, and the porous film obtained in the above (1) is used. Were laminated to obtain a laminated film of the present invention. The obtained laminated film was spread with the substrate surface facing downward so as to sufficiently cover the roots of the peach tree at the time of flowering.
After that, normal cultivation was carried out for about 4 months, and the sugar content of the obtained fruits was measured with a Brix sugar content meter. Further, the tear strength and surface strength of the used porous film were measured. The results are shown in Table 2.

Example 2 100 parts by weight of the same polyolefin resin (mixture) used in Example 1 was surface-treated with phosphate ester (Daiichi Kogyo Seiyaku Co., Ltd., Plysurf A208B 2% treatment) to give calcium carbonate. A laminated film was obtained in the same manner as in Example 1 except that 130 parts by weight and 40 parts by weight of zinc oxide were used. The results are shown in Tables 1 and 2.

Example 3 100 parts by weight of the same polyolefin resin as used in Example 1 was added to phosphoric acid ester (Daiichi Kogyo Seiyaku Co., Ltd.).
A laminated film was obtained in the same manner as in Example 1 except that 150 parts by weight of calcium carbonate and 20 parts by weight of titanium oxide surface-treated with Plysurf A212C (treated with 2.5%) were used. The results are shown in Tables 1 and 2.

Comparative Example 1 A laminated film was obtained in the same manner as in Example 1 except that calcium carbonate as a filler, which was not surface-treated, was used. The results are shown in Table 1 and Table 2.
Shown in.

[0055]

[Table 3]

[0056]

[Table 4]

[0057]

EFFECTS OF THE INVENTION The laminated film or sheet of the present invention has good moisture permeability and air permeability and excellent weather resistance. Therefore, by using it as a soil coating material during fruit tree cultivation, it is possible to improve the sugar content of fruits. Can be done.

Claims (4)

[Claims] 1. A (A) density of 0.965 g / cm on a substrate.
³ or less, 100 parts by weight of a polyolefin resin having a melt index of 10 g / 10 min or less, (B) 25 to 400 parts by weight of a filler surface-treated with a phosphate ester, and (C)
A film or sheet obtained by forming a resin composition comprising 0.1 to 10 parts by weight of a hindered amine light stabilizer and (D) 0.1 to 10 parts by weight of a benzotriazole-based or benzophenone-based or benzoate-based UV absorber. A soil coating material comprising a laminated film or sheet having a porous polyolefin layer obtained by uniaxially stretching in at least the take-up direction. 2. The porous polyolefin layer has a (A) density
0.965 g / cm ³Below, melt index 10g
100 parts by weight of a polyolefin resin of / 10 min or less,
(B) Filler 25-40 whose surface is treated with phosphate ester
0 parts by weight, (C) hindered amine light stabilizer 0.1 to
10 parts by weight and (D) benzotriazole type or benzo
Phenone-based or benzoate-based UV absorber 0.1-1
0 parts by weight, and (E) metal salts of acidic phosphoric acid ester.
Obtained by molding a resin composition comprising 1 to 10 parts by weight
Place the film or sheet in at least its take-up direction.
A product obtained by axial stretching, wherein
The soil coating material described. 3. The porous polyolefin layer has a (A) density
0.965 g / cm ³Below, melt index 10g
100 parts by weight of a polyolefin resin of / 10 min or less,
(B) Filler 25-40 whose surface is treated with phosphate ester
0 parts by weight, (C) hindered amine light stabilizer 0.1 to
10 parts by weight and (D) benzotriazole type or benzo
Phenone-based or benzoate-based UV absorber 0.1-1
0 parts by weight, (F) ester bond or amide in the molecule
A molecular weight of 100 or more having a bond, a boiling point of 200 ° C. under normal pressure
Above, 1 to 100 parts by weight of a plasticizer having a melting point of 100 ° C. or less, and
(G) Radical generator 0.0001 to 0.1 part by weight
Or sheet obtained by molding the resin composition comprising
Uniaxially stretched in at least its take-up direction
The soil covering material according to claim 1, which is a thing. 4. The (A) density of the porous polyolefin layer
0.965 g / cm ³Below, melt index 10g
100 parts by weight of a polyolefin resin of / 10 min or less,
(B) Filler 25-40 whose surface is treated with phosphate ester
0 parts by weight, (C) hindered amine light stabilizer 0.1 to
10 parts by weight and (D) benzotriazole type or benzo
Phenone-based or benzoate-based UV absorber 0.1-1
0 parts by weight, and (E) metal salts of acidic phosphoric acid ester.
1 to 10 parts by weight, (F) an ester bond in the molecule or
Molecular weight of 100 or more with amide bond, boiling point at normal pressure 2
1 to 100 weight of plasticizer having a melting point of 100 ° C. or higher and 00 ° C. or higher
Parts and (G) radical generator 0.0001 to 0.1 weight
Or a film obtained by molding a resin composition comprising
Obtained by uniaxially stretching the sheet in at least its take-up direction
The soil cover according to claim 1, wherein the soil cover is
Covering material.