JPS62174243A - Agricultural film - Google Patents

Abstract

PURPOSE:To provide the title film which has excellent tranparency, heat retainability, slipperness and mechanical strength, can be produced with high productivity and inexpensively, by molding a compsn. consisting of an olefin resin and a specified alumina/silica compounding agent. CONSTITUTION:Zeolite is used as a preceursor and treated with an acid to obtain an alumina/silica compounding agent (B) which has a homogeneous chemical composition, is composed of Al2O3 and Sio2 in a molar ratio of 1:1.8-5, has a refractive index of 1.46-1.52 and evenness in paticles, whose primary particle has a well-defened cubic or spherical form and a diameter of 5mu or below as measured with an electron microscope, which is amorphous by X-ray diffractometry and has a BET specific surface area of 100m<2>/g or below and an ignition loss (850 deg.C, 30min) of 30% or below. An olefin resin (A) (e.g., low-density PE) is blended with 0.5-30wt% component B and optionally an antioxidant, a lubricant, an antistatic agent, etc. (c). The resulting compsn. is molded into a film by an inflation method, a calendering machine or a T-die extrusion.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an agricultural film, and more particularly to an agricultural film that has excellent transparency, heat retention, and slipperiness.

(Conventional technology) Conventionally, greenhouse covering films used for greenhouse cultivation include:
Polyvinyl chloride film, polyethylene, and olefin resin film made of ethylene-vinyl acetate copolymer are used, but the latter resin film has inferior heat retention properties compared to the former, so it is suitable for use in the infrared wavelength range. Inorganic additives such as amorphous silica and alumina-silica, which have a light-blocking ability, are added to improve heat retention.

However, known inorganic compound-containing films have uneven surfaces, low transparency, and high friction. It has been proposed to laminate them (Japanese Utility Model Publication No. 52-69447 and Japanese Patent Publication No. 60-37792).

(Problems to be Solved by the Invention) The reason why amorphous silica and alumina-silica particles are used as compounding agents is that their refractive index is within a range similar to that of olefin resins. Therefore, the blended resin composition has excellent transparency, but the actual olefin resin film obtained by blending known amorphous silica or alumina-silica particles has poor transparency. Even if these particles themselves are fine, when they are dispersed in a resin for 1 meter, these particles aggregate to form a large primary particle structure, which causes unevenness on the surface. It is presumed that this will be formed.

However, it can be said that if an olefin resin film filled with an inorganic compound that has excellent transparency, heat retention, and slipperiness even in the middle layer state can be obtained, there will be many advantages in terms of price and productivity. does not require

Therefore, the technical problem of the present invention is to find an inorganic compounding agent for agricultural films that has excellent transparency, heat retention, and slipperiness even in a single layer state when blended with an olefin resin. .

(One Step for Solving the Problems) According to the present invention, an agricultural product formed from a composition containing an olefinic resin and an alumina-silica blending agent of 0.5 to 30% by weight per olefinic resin. In the film for which the alumina-silica compound is Al2O3:
consisting of particles having a composition with a molar ratio of 5iOz in the range of 1:1.8 to 1:5 and having a distinct cubic to spherical primary particle shape and an electron microscopy primary particle diameter of 5 microns or less, Single-nucleus grains are substantially amorphous in terms of X-ray diffraction and have a density of 100 rn'/gJ! An agricultural film is provided having a BET non-surface field of F.

In the present invention, in addition to using the above composition in the form of a single layer film, a surface layer of an olefin resin containing no alumina-silica compound is provided on the surface of a base layer made of this composition, and a laminated film is formed. It can also be used in the form of

(effect) The alumina-silica compound used in the present invention is as follows.

It is obtained by using zeolite as a precursor and treating it with an acid. Although these particles are amorphous in terms of X-ray diffraction, their chemical composition is homogeneous not only between particles but also within the particles, with a molar ratio of Al2O3:SiO of 1.
: Constant within the range of 1.8 to 1:5. Therefore, the refractive index of these particles is constant within the range of 1.46 to 1.52, and there is almost no variation among the particles, which is a remarkable feature of WJ.

Furthermore, since the refractive index of this material is different from that of the olefin resin, it is possible to obtain an olefin resin composition with excellent transparency.

In addition, this alumina-silica compound has a crystal particle shape unique to zeolite, and shows a clear W-cuboid to spherical primary particle shape and an electron microscopy primary particle diameter of 5 microns or more F. This is the first feature, and this means that the compounding agent of the present invention has almost the same particle size and primary particle size, and this compounding agent is in the form of particles in the olefin resin. It has the advantage that it is evenly and finely dispersed, and as a result, there is almost no formation of irregularities on the surface of the produced film.

Therefore, the film according to the present invention has excellent transparency even in a single layer state, and has the advantage of having a significantly smaller haze (1n degree) than conventional silica, alumina-silica, etc. In addition, 1) the formation of surface irregularities is small, this compound itself has excellent lubricity, and is also remarkably excellent in friction resistance and abrasion resistance, and because it has the aforementioned dispersed structure, it is relatively Even if it is contained in a large amount, there is little decrease in film strength; for example, when the content is 5% by weight, almost no decrease in strength is observed.

It is also important that this compounding agent be essentially amorphous; in the case of crystalline zeolite particles, foaming occurs due to the separation of water from crystallization during film forming, which reduces transparency. Foaming like smoke is also prevented.

Moreover, since the alumina-silica compound used in the present invention is an amorphous material having the above-mentioned chemical composition, it has particularly excellent infrared shielding properties and has an extremely large heat retention effect.

(Description of preferred embodiments of the invention) The alumina-silica resin compound used in the present invention is: A
It has a composition in which the molar ratio of 12O3:5i02 is in the range from 1:1.8 to 1:5, in particular from 1:1.8 to 1:4. If the molar ratio of Ah (h: 5i02) is outside the above range, it will be difficult to form this alumina-silica into η-cuboidal or spherical particles with a clear and constant particle size, and furthermore, it will be difficult to form the alumina-silica into ηcuboidal or spherical particles with a constant particle size. The properties are also inferior to those within the scope of the present invention.

In this alumina-silica-based particles, 850°C
The moisture content, defined as loss on ignition in 30 minutes, is generally below 30%, in particular in the range 10%. This water content varies depending on the manufacturing conditions of the alumina-silica particles, and the water content is in the range of 1 to 30% for particles as-manufactured by the method detailed later, but when dried or As the temperature of calcination increases, the water content gradually decreases.
Silica-based particles are preferred.

In addition to the essential alumina and silica components, the alumina-silica compound used in the present invention contains a small amount of basic components,
In particular, it is permissible to contain an alkali metal component. However, the content of this alkali metal is A 1203:
It is noteworthy that the molar ratio of S i02 is within the same range and is 50% or less, especially 30% or less, of the alkali metal content of a certain zeolite, and the content of basic components is significantly lower than that of zeolite. Should.

Several examples of compositional weights of alumina-silica blends particularly desirable for the purpose of the present invention are shown below.

1st type Al20327~45% 5i0232~55% Na2O0,1~20% H2025% or less 11th type Al2O338~54% 5iOz 32~64% Na2O0,1~20% 820 30% 1st type m AlO247~64% 5i0238~78% Na20Q, I -20% lho 30% or more What is conventionally known is what is called amorphous zeolite. This amorphous zeolite is produced by aging and reacting a composition whose alumina content, silica content, alkali metal content, and water content are within the zeolite-forming range, and stopping the reaction before zeolite crystals begin to crystallize. , alumina part 1
The silica content and the alkali metal content are contained in a ratio of -1,1, which is approximately the same as that of crystalline zeolite. On the other hand, in the formulation used in the present invention, the alkali metal content is significantly lower than that of amorphous zeolite, and in this respect, they can be clearly distinguished.

The alumina-silica resin compound used in the present invention also includes:
Although substantially amorphous in X-ray diffraction, it exists as cubic particles of constant size and shape of 7 g. In the accompanying drawings, Figure 1-A is an X-ray diffraction diagram (α for Cu-) of zeolite A, and Figure 1-B is an X-ray diffraction diagram of the alumina-silica compound used in the present invention. . Furthermore, Figure 2 A is an electron micrograph of A ((j'
? -f4to, ooo magnification), and Figure 2-B is an electron micrograph of this alumina-silica compound (magnification 10,
000 times).

Conventionally, amorphous alumina-silica has been used for example alumina-silica.
In many cases, like silica gel, the primary particles have an amorphous shape, and there are almost no known particles that have a clear cubic or spherical shape as in the present invention.

In the formulation of the present invention, the cubic particles have a primary particle size of less than 5 microns, in particular less than 1 micron, as measured by electron micrograph. From the standpoint of preventing agglomeration of compounding agent particles, this -order particle size is 0.
．． It is desirable that the thickness be 1 micron or more.

Furthermore, the amorphous alumina-silica particles t used in the present invention have a BET specific surface area of 1 oorn'/g or more, particularly 50rn'/g or less, in relation to having the above-mentioned particle morphology and particle size characteristics. have That is, while known amorphous alumina silica has a specific surface area that is considerably larger than room''/g, the alumina-solikake cubic particles of the present invention have an extremely small specific surface area and are difficult to knead with resin. In addition to being easy to mold, there is little tendency to increase the melt viscosity when molding into a film, and it has excellent moldability.

Furthermore, the formulation particles used in the present invention have a bulk density in the relatively large range of 0.3 to 0.7 g/cc in conjunction with their cubic shape and relatively large primary particle size. 1. For example, the bulk density is 1.5 times that of known silica-based antiblocking agents, and it is extremely easy to blend into resins.

The amorphous alumina-silica blend particles of the present invention are made of crystalline zeolite having a cubic particle morphology under conditions in which the crystal structure is substantially destroyed but the particle morphology is not substantially stacked. It is produced by neutralizing with acid to remove the alkali metal content in the zeolite.

As the raw material crystalline zeolite, zeolite A, zeolite

The acid to be used may be either an inorganic acid or an organic acid without particular restriction, but economically speaking, hydrochloric acid and sulfuric acid are preferred.

Acids such as nitric acid and phosphoric acid are used. These acids are used in the form of dilute aqueous solutions for the neutralization reaction with the crystalline zeolite.

When an acid is added to an aqueous slurry of crystalline zeolite, the pH naturally shifts to the acidic side as the acid is added, but after the addition is complete, the pH of the liquid shifts to the alkaline side again, resulting in a constant pH of -.
There is a tendency to saturate the value. This saturated pH is 1, that is, the stable pH is 7.0 to 3.0. In particular, it is desirable for the purpose of the present invention to neutralize to a range of 6.5 to 4.0.

When this pH is higher than the E range, Zeolite I.
It becomes difficult to effectively remove the alkali content therein and make it amorphous. On the other hand, when the pH is lower than the above range, the alumina content in the zeolite also tends to be eluted, making it difficult to leave cubic particles in the form. MFM to use
is more than 50% of the alkaline content in the zeolite, especially 70%
It must be sufficient to remove % or more.

Amorphous alumina-silica cubic particles obtained by eluting and removing alkaline components through acid treatment are cancer-free,
If necessary, it is washed with water, dried, or further fired if desired to obtain a resin compound.

Olefin resins Olefin resins are mainly composed of α-olefin homopolymers, copolymers of α-olefins, or α-olefin intermediates, and other polymers (including copolymers including breadth polymers) are used. Examples of polymers or polymer blends containing two or more of these include, but are not limited to, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene- These include butene-1 copolymer, ethylene-propylene-butene terpolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ion i! bridge ethylene copolymer (ionomer), etc. However, low-density polyethylene and ethylene-vinyl acetate copolymers with a vinyl acetate content of 0.5 to 25!1f% are preferred.These ethylene polymers generally have a melt flow rate of 0.1 to 10 g/10 min. It is preferable to have a rate.

Compositions and Films In the present invention, it is preferable to incorporate an alumina-silica compounding agent in an amount of 0.5 to 30% by weight, especially 1 to 10% by weight, based on the olefin resin.If the amount is less than the range E, heat retention is improved. If the amount is not sufficient or exceeds the above range, the mechanical properties of the film will deteriorate.

Of course, this composition contains ingredients that are known per se.

For example, antioxidants, lubricants, antistatic agents, etc. may be added according to known formulations.

This composition is kneaded in a roll-type or Banbury-type mixer or extruder, and then subjected to a method known per se, such as an blown film-forming method, a calendar film-forming method, or a T-die film-forming method. Form it into a film. The thickness of the film is not particularly limited, but is generally in the range of 20 to 100 mm.

The film of the present invention sufficiently achieves the intended purpose with a single layer,
Although the desired effect is achieved, if desired, a surface layer of an olefin resin containing no compounding agent can be provided on the base layer made of the composition. This lamination can be performed by a :P method known per se, such as a coextrusion method, an extrusion coating method, or a sandwich lamination method. The thickness of the surface layer can range from 10 to 20 microns.

(Operations and Effects of the Invention) According to the present invention, an agricultural film of olefin resin having excellent transparency, heat retention, and slipperiness even in a single layer state can be obtained, and this film can be produced at low cost and with high productivity. It becomes possible to provide the In addition, there is no decrease in film strength that occurs when inorganic additives are added! It has the advantage of being able to maintain a high level of mechanical strength.

(Example) The excellent effects of the present invention will be specifically explained below using examples.

Reference Examples 1 and 2 The zeolite used in this reference example is a 4A type zeolite synthesized by the following method.

As the silicic acid content, a fine particle silicic acid gel obtained by acid-treating acid clay from Nakajo, Niigata Prefecture, which is a smectite group clay mineral, was selected.

Acidic clay from Nakajo, Niigata Prefecture, has a moisture content of 45% in its natural state.
The main components are 5i0272.1 and Al2O3 in dry matter weight percent (drying at 110°C).
14,2,Fe2033.8? , MgO3, 25°C
aO1,o[l, loss on ignition was 3.15. This raw acidic mound was formed into a cylinder shape with a diameter of 5 mm and a length of 5 to 20 mm, and an amount equivalent to 765 g in terms of dry matter was collected into 51 conical beakers, and two 50% by weight sulfuric acid solutions were added. Addition, heating to 90℃, treatment time 7
After choosing a time and treating the two grains with acid, the sulfate of the basic component that reacted with the sulfuric acid was removed using a decantation method using a dilute sulfuric acid solution and water, followed by washing with water until the sulfuric acid was removed. A granular acid-treated product on an acidic ridge was obtained.

Next, in order to produce zeolite, the granular acid-treated product produced in the above steps was first put into a household mixer (11 manufacturing units) in order to distribute the particle size to a suitable state as a synthetic raw material.
ami + t-1VA-853 type), water was added so that the solid content concentration was 20% by hair volume, and the mixture was stirred and crushed for 20 minutes.
Next, the mixture was classified using a 200-mesh wire mesh and pulverized for 3 hours in a 7-cross ball mill to obtain a slurry of acid-treated clay whose particle size had been adjusted.

The particle size distribution (z) was kept constant at Jl, and the results are shown in Table 1 below.

Table 1 In addition, chemical composition analysis (based on 110°C dry matter!] 1% by weight) of the acid-treated viscosity slurry obtained here was conducted,
The results are shown below.

Burning 8 reduction state 3.93.5iO294,+9, Al2Ch
1.05.

Fe2030. +5, C:aQ O,49, to g(l
As the manufacturing conditions for the O,lQ zeolite, first, the following molar ratio was selected based on the chemical resistance as the composition molar ratio.

Na2O/5i02 = 1.2 Si02/Ah (h = 2.0 H2O/Na20 = 35 In order to achieve the above required composition molar ratio, alumina is added to the slurry of the acid-treated product with viscosity, where it is insufficient. The alkali content necessary for the reaction and the water essential for the reaction are added to the reprint reagent alkali aluminate solution (Ml composition Na2O21,
0! , Al2O3 (18.8%)) and water were mixed to achieve the desired mixing ratio as described above, and this mixed solution was mixed in 11! The slurry of the acid-treated product and the purified mixture were placed in a 10-liter stainless steel container. When the raw materials are mixed by stirring, this mixed system passes through a gel-like state for ~ hours and is obtained as a homogeneous slurry. Next.

When heated to 95°C and stirred for 3 hours, crystal grains of alkali aluminosilicate (zeolite) are formed. After crystal formation, the reaction product containing crystals and the reaction mother liquor were aged at the above temperature for 2 hours and then filtered.
Separate the filter cake, collect the reaction product, and add 4 parts of ion-exchanged water to 1 part by weight of the dried product. After addition and mixing at a star ratio of □'L811 and stirring to form a homogeneous slurry, this lJ liquid was separated again by the sieve method. At this time, the pH of the ψ solution was 12.5. The primary particle diameter of this product as measured by a scanning electron microscope was approximately 0.5 mm. In addition, it was confirmed by X-ray diffraction that it was 4A type zeolite (Reference Example-
1).

After dispersing 515 g of this 4A type zeolite (>+iJ cake 10100O anhydride) in 5 ml of dilute sulfuric acid adjusted to pH 2, it was prepared using a high-speed stirrer attached to 200 g of dilute sulfuric acid. ; Pour L dilute sulfuric acid into L container at the same time. The amount of dilute sulfuric acid used was 1721, and the pH at time T, the end of the injection, was 5.8. Next, it was heated to 50"C and held for 1 hour, and then washed with water and dried.
After firing at 50°C for 2 hours, the mixture was pulverized using an atomizer to obtain an amorphous aluminosilicate. Table 2 shows the physical properties of this product.

The test method in this example was as follows.

(1) Packing density Based on JIS-K 6220.

(2) Specific surface area: 0.
5～o、e gPut in a weighing bottle and dry at constant temperature of 150℃μ
Dry for 1 hour in a refrigerator and immediately weigh the sample accurately. This sample was placed in an adsorption sample tube (2 to 5 m1) and heated to 200°C, degassed until the degree of vacuum within the adsorption sample tube reached 10'ff1mHg, and after being left to cool, it was placed in liquid nitrogen at approximately -196°C. Place the sample tube in front of the eye and set Pn2/Po” 0.05 to 0.30 (Pn2:
The amount of N2 gas adsorbed is measured at 4 to 5 points between the nitrogen gas pressure (po: atmospheric pressure at a constant time of 11 and 13). Then, convert the adsorption amount of N2 gas after subtracting the dead volume to the adsorption amount at 0°C and 1 atm, and substitute it into the BH3 formula to obtain Vm [ml/g]
(indicates the amount of nitrogen gas adsorption required to form a monomolecular layer on the sample surface).

The specific surface v1s is determined by the following equation.

S = 4.35XVa+ [nf/g] (3) Oil absorption J Is- -5101.

(4) Whiteness According to J.A5-P-8101.

(5) Particle size sample for electron microscopy Take an appropriate amount of fine powder onto a sample plate, coat it with a metal coating device (Hitachi model E-101 ion sputter) and use it as a photographic sample. Using a scanning electron microscope (Hitachi S-570), the field of view is changed to obtain four 10,000x electron micrograph images suitable for primary particle measurement using a conventional method. Six representative particles were selected from among the cubic particle images in the field of view, and the length of the - side of each cubic particle image was measured using a scale, and the length was expressed as the primary particle diameter in Examples herein.

(8) Xi! The crystallinity sample obtained by a-diffraction was passed through a standard sieve of 200 a+esh in advance, and dried together with the standard and sample (UCC Na-A type zeolite standard and sample) in a constant temperature drying oven at 105°C x 3 hrs'il. Thereafter, the mixture is allowed to cool in a desiccator, subjected to Jlll determination of X-ray diffraction, and the degree of crystallinity is calculated according to the F formula.

(Apparatus) Rigaku Denki X-ray diffractometer goniometer PMG-s2 Rate meter ECP-D2 (Measurement conditions) Target Cu Filter Ni Voltage 35kV Current 20mA Count full scale 4X103 C/S Time constant 1 sec Chart speed 1cm/ l1in Scanning speed 1°/win Diffraction angle 10 Slit 1] 0.15 m++*Measurement range
2θ=20°~32″Na-A zeolite crystallinity=100 (7) Particle size distribution Seishin Enterprise Micron Fortcycer 5KN-100
Measurement was carried out using Type 0.1 A 0.2% aqueous solution of sodium pyrophosphate was used as the dispersion medium. At the beginning of measurement, adjust the zero point and swing width of the recorder using only the dispersion medium. The amount of light transmitted through the blank is adjusted to log 1.95 of the recording paper.

The sample dispersion liquid was prepared as follows.

Take 100ml of dispersion medium in a 200ml beaker, add 15mg of sample, and add SK Disperser (,
Disperse for about 2 hours using a TFI 9-wave disperser). On this occasion,
Stir with a stirrer while waiting. After dispersion is completed, the liquid is cooled or heated until it reaches a predetermined temperature. This dispersion liquid is poured into the glass cell up to the marked line while maintaining a uniformly dispersed state. When the cell is set in the cell holder and the light source lamp is turned on, if the pen of the recorder is between log 1.3 and log 1.4, the concentration of the dispersion liquid is appropriate. log
If it is less than 1.3, it is too thick, logl, and if it is more than 4, it is too thin, so re-preparation is performed.

A111 constant is carried out under the conditions that the maximum particle size is 30 g.

Reference example 3 Sodium silicate solution (composition 5i0218.0%, Na2
0B, 2%) j 670g and aluminium powder solution (composition AI?Or, 13.4%, Na2O13, o$)
A homogeneous slurry of aluminosilicate alkali gel was prepared by gradually adding and mixing 2,000 g and 1,550 g of wood in a 10-gram stainless steel container with high speed stirring.

When this aluminosilicate alkali gel slurry is heated to 95° C. without stirring and reacted with stirring for 5 hours, aluminosilicate alkali (zeolite) crystal particles are generated.

After crystal formation, the mixture was aged at the above temperature for 2 hours, and the reaction Lq liquid was separated in the same manner as in the above method, and the filtrate cake was collected.

To this filter cake, 4 parts by weight of ion-exchanged water was added per 1 part by weight on a dry matter basis, mixed and stirred to form a homogeneous slurry, and the mother liquor was separated by a filter method. This operation was performed three times.

The primary particle diameter of this material was approximately 2.3 microns as measured using a single-shield WJ microscope. Furthermore, it was confirmed by X-ray diffraction that it was a 4A type zeolite.

Approximately 1000 g of this 4A type zeolite cake was adjusted to pH
After dispersing in 5 ml of dilute sulfuric acid prepared in Example 2, the mixture was treated in the same manner as in Reference Example 1 in a 200-degree vessel equipped with a high-speed stirrer.

The properties of the obtained product are shown in Table 1.

The amorphous aluminum silicate gel used in Reference Example-4 was prepared by the method described in F.

Sodium silicate solution (composition 5iO219,8!, Naz
Aluminum sulfate solution (Al
10% as 2Ch) 1000g and 5000g of water about 3
Gradually add and mix over a period of 0 minutes to make a homogeneous aluminosilicate gel slurry, react for 3 hours under heating at 95°C, then filter for 7 hours, separate the ψ liquid, and thoroughly wash with ion-exchanged water. After that.

The filtered cake was dried in a constant temperature dryer at 110'C, pulverized,
A predetermined powder amorphous aluminum silicate gel was prepared by classification.

The measured properties are shown in Table 1.

Example 1 The following No. 1
The alumina-silica compounding agents shown in the table were compounded according to the methods shown in Table 2, melt-kneaded in an extruder at a temperature of 150'0, and then pelletized.

The pellets were fed into an extruder and formed into a film with a thickness of 70 microns under conditions of a melting zone of 160°C, a temperature of 170°C, and an expansion ratio of 2.0.

The following physical properties were measured for each film obtained.

Haze According to ASTM-D-1003.

Tensile strength at break According to AS'rM-D-838-587.

A semi-cylindrical tunnel coating with a diameter of 20 cm was formed on the ground using a heat-retaining sample film, and the temperature at night (3 a.m.) at the center of the ground was measured.

It is expressed as a temperature difference (ΔT) based on the temperature of a polyethylene film containing silica-alumina particle bundles.

Abrasion resistance According to ASTM-D-1044.

The results obtained are shown in Table 2.

Example 2 Both surfaces of the film of Sample 2 of Example 1 were extrusion coated with the low-density polyethylene used in the practical mold without any compounding agents applied thereto to a thickness of 20 microns.

The degree of haze of this laminated film was 8.7%.

[Brief explanation of drawings]

Figure 1-A is an X-ray diffraction diagram of zeolite A, Figure 1-B
Figure 1 shows an X-ray diffraction diagram of the alumina-silica compound used in the present invention. Figure 2A shows an electron micrograph of zeolite A (magnification 1).
Figure 2-B is an electron micrograph (10,000x magnification) of the alumina-silica compound used in the present invention. Patent Applicant: Mizusawa Chemical Industry Co., Ltd. - Hand Thread Sales Negative 11 Original Book (Method)
(April 8, 1986

Claims (2)

[Claims] (1) Olefin resin and 0.5 per olefin resin
An agricultural film formed from a composition containing 30% by weight of an alumina-silica compound, wherein the alumina-silica compound is Al_2O_3:SiO
consisting of particles having a composition in which the molar ratio of _2 is in the range of 1:1.8 to 1:5 and having a distinct cubic to spherical primary particle shape and an electron microscopy primary particle diameter of 5 microns or less, An agricultural film characterized in that the particles are substantially amorphous in terms of X-ray diffraction and have a BET specific surface area of 100 m_3/g or less. (2) Olefin resin and 0.5 per olefin resin
Agriculture comprising a laminate of a base layer made of a composition containing 30% by weight of an alumina-silica compound and a surface layer of an olefin resin not containing the compound applied on the surface of the base layer. In the film for which the alumina-silica compound is Al_2O_3:SiO
consisting of particles having a composition in which the molar ratio of _2 is in the range of 1:1.8 to 1:5 and having a distinct cubic to spherical primary particle shape and an electron microscopy primary particle diameter of 5 microns or less, An agricultural film characterized in that the particles are substantially amorphous in terms of X-ray diffraction and have a BET specific surface area of 100 m^2/g or less.