KR20210146358A - Film and Agricultural and Horticultural Facilities - Google Patents

Abstract

A film having a large change in light scattering properties in the range of about 0°C to 40°C is provided. The film has at least one layer comprising a continuous phase and a dispersed phase, and (A) the ratio of the area of the cross-section of the dispersed phase with the equivalent circle diameter of 1 µm to 10 µm among the dispersed phase is 1% with respect to the area of the cross-section of the layer or more and 30% or less, (B) the coefficient of linear expansion ^{satisfies 1.5×10 −4} K ⁻¹ or more and 2.8×10 ⁻⁴ K ⁻¹ or less.

Description

Film and agricultural and horticultural facilities

FIELD OF THE INVENTION The present invention relates to films and agricultural and horticultural facilities.

In Patent Document 1, a transparent resin molded article formed of a resin composition comprising a plurality of resins having mutually different temperature dependence of refractive index, wherein the refractive index difference of these resins at at least one temperature within the operating temperature range is 2 × 10 ^{-2 or less.} is described.

Japanese Laid-Open Patent Publication "Japanese Patent Application Laid-Open No. 2001-123076"

It is calculated|required by a film to prevent the fall of insolation amount throughout the year, as well as to prevent damage to the leaf|foliage etc. of crops resulting from excessive direct sunlight by increasing light scattering property in summer when solar radiation is strong. For this reason, while showing low light scattering property under the low temperature of winter season, it shows high light scattering property under the high temperature of summer, and the film with a large change depending on the temperature of the light scattering property is calculated|required.

The inventors of the present invention have found that the coefficient of linear expansion in a direction perpendicular to the surface of a film having at least one layer comprising a continuous phase and a dispersed phase is within a predetermined range, so that the change in light scattering properties in the film is large and rigidity It found out that this increased, and came to complete this invention.

On the other hand, Reference 1 does not describe the relationship between the coefficient of linear expansion of the entire film and the change in light scattering properties of the film. Moreover, since the transparent resin molded object of the Example described in Cited Document 1 has a small amount of polyethylene added at 5 wt%, it is considered that the coefficient of linear expansion of the entire film is small.

One aspect of the present invention aims to provide a film having a large change in light scattering properties in the range of about 0°C to 40°C and excellent in rigidity.

In order to solve said subject, the film which concerns on one aspect of this invention has at least one layer which consists of a continuous phase and a dispersed phase, and the following (A) and (B) are satisfied;

(A) In the cross section cut in the direction perpendicular to the film surface and parallel to the slow axis in the film plane, the ratio of the area of the cross section of the dispersed phase with the equivalent circle diameter of 1 µm to 10 µm among the dispersed phases is 1% or more and 30% or less with respect to the area of the cross-section of the layer;

(B) the coefficient of linear expansion calculated by the following formula (1) is 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less,

Coefficient of linear expansion = (L _{25 ℃} - L _{0 ℃} )/(25 ℃ - 0 ℃) (1)

Here, L _25° C represents the length of the film in the direction perpendicular to the film surface at 25°C, and L _0°C represents the length of the film in the direction perpendicular to the film surface at 0°C.

Moreover, another preferable aspect of this invention is an agricultural/horticultural facility in which the said film was fully mounted in the agricultural/horticultural facility frame.

ADVANTAGE OF THE INVENTION According to one aspect|mode of this invention, the change of the light scattering property in the range of about 0 degreeC - about 40 degreeC is large, and the film with high rigidity can be provided.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment which concerns on this invention is described in detail.

<Agricultural Film>

An agricultural film according to one embodiment of the present invention is a film having at least one layer comprising a continuous phase and a dispersed phase, and has a coefficient of linear expansion of 1.5 × 10 ^{-4 in a direction perpendicular to the film surface (also referred to as a thickness direction).} It is K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less. The agricultural film according to one embodiment of the present invention can be preferably used as an exterior or interior film of a greenhouse for plant cultivation, a covering material for a tunnel, and the like.

(Coefficient of linear expansion)

In this specification, the coefficient of linear expansion is the ratio of the change amount ΔL of the length to the change amount ΔT of the temperature, and is expressed as ΔL/ΔT. In this specification, the linear expansion coefficient in the perpendicular|vertical direction with respect to the agricultural film surface which concerns on one aspect of this invention is computed by following formula (1).

Coefficient of linear expansion = (L _{25 ℃} - L _{0 ℃} )/(25 ℃ - 0 ℃) (1)

Here, L _25°C is the length of the film in the direction perpendicular to the film surface at 25°C, and L _0°C is the length of the film in the direction perpendicular to the film surface at 0°C. That is, the agricultural film which concerns on one aspect of this invention employ|adopts the thickness of a film as a reference|standard of the length for calculating|requiring a linear expansion coefficient.

The inventors of the present invention, (i) when the film is a single layer, the coefficient of linear expansion in the thickness direction of the layer consisting of the continuous phase and the dispersed phase to be described later, (ii) the layer in which the film consists of the continuous phase and the dispersed phase and other layers When it has, it discovers that the linear expansion coefficient in the thickness direction as the said whole film affects the change of the light scattering property in the said film largely, and has completed this invention.

The agricultural film according to one embodiment of the present invention has a coefficient of linear expansion of 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less in a direction perpendicular to the film surface, and is 1.7 × 10 ^-4 K ^{It is -1} or more, and it is more preferable that it is ^{2.6 x 10 -4} K ^{-1 or less.} When the coefficient of linear expansion is 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less, light scattering property can be increased in the summer reaching around 40 ° C, and light scattering property can be lowered in the winter season reaching around 0 ° C. . Specifically, the haze value can be made high in the summer reaching around 40°C, and the haze value can be made low in the winter season reaching around 0°C. Moreover, the rigidity of a film can be made high because a coefficient of linear expansion is 2.8 x 10 ^-4 K ^{-1 or less.} Specifically, the value of 1% SM mentioned later can be made high. When the linear expansion coefficient of a film ^{becomes smaller than 1.5x10 -4} K- ¹ , the change of the light-scattering property in the temperature range of 0 degreeC - 40 degreeC becomes small. Specifically, the change of the haze value in the temperature range of 0 degreeC - 40 degreeC becomes small. Moreover, when the coefficient of linear expansion of ^{a film becomes larger than 2.8*10 -4} K ^-1 , the rigidity of the said film will become low.

A coefficient of linear expansion is measured using the test piece which cut out the film to the size of 5 mm x 5 mm. The thermomechanical analyzer is set to compression mode, and the test piece is cooled to -15°C or less under the condition of a load of 0.05 N. Then, while heating up to 60 degreeC at a rate of 5 degreeC/min, the length in the direction perpendicular|vertical to the surface in 0 degreeC and 25 degreeC, ie, thickness, is measured, and the linear expansion coefficient is calculated|required from the above-mentioned formula (1) . The measurement of the coefficient of linear expansion is performed in a helium atmosphere. In addition, in the measurement of a coefficient of linear expansion, the thickness of a film is not prescribed|regulated. However, as will be described later, the linear expansion coefficient of the test piece cut out from the film is 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less of the layer consisting of the continuous phase and the dispersed phase in the film. The ratio of the thickness and the material from which the film is made are determined.

In addition, the coefficient of linear expansion of the agricultural film which concerns on one aspect of this invention may just be calculated|required as a coefficient of linear expansion of only the said layer, when the said agricultural film consists only of the layer which consists of a continuous phase and a dispersed phase. Moreover, what is necessary is just to calculate|require as a linear expansion coefficient of the agricultural film which consists of all of those layers, when it is provided with layers other than the layer which consists of a continuous phase and a dispersed phase (namely, other layers mentioned later). That is, the agricultural film according to one aspect of the present invention has at least one layer comprising a continuous phase and a dispersed phase, and has a coefficient of linear expansion in a direction perpendicular to the surface of the film including the layer of 1.5 × 10 ^-4 K ^-1 or more The structure of the layer which a film has is decided so that it may become 2.8 x 10 ^-4 K ^{-1 or less.} Thereby, the change of the haze value in the temperature range of 0 degreeC - 40 degreeC can be enlarged. Agricultural film according to one aspect of the present invention has a linear expansion coefficient of 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less, [continuous phase], [dispersed phase], and [other layers] It can be manufactured by appropriately adjusting the conditions of the raw material and manufacturing method mentioned later in. When the coefficient of linear expansion is 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less, light scattering property can be increased in the summer reaching around 40 ° C, and light scattering property can be lowered in the winter season reaching around 0 ° C. . That is, the change of the light scattering property in the range of about 0 degreeC - about 40 degreeC can be enlarged.

A coefficient of linear expansion can be adjusted so that it may become ^{1.5 x 10 -4} K ^-1 or more and 2.8 x 10 ^-4 K ^-1 or less by appropriately adjusting the following (a) and (b), for example.

(a) Kinds and ratios of components of each phase in the layer comprising the continuous phase and the dispersed phase

(b) The ratio of the thickness of the layer which consists of a continuous phase and a dispersed phase in a film

The details of the relationship between the above (a) and (b) and the coefficient of linear expansion will be described later.

Hereinafter, in this specification, when described as "coefficient of linear expansion", unless otherwise specified, "coefficient of linear expansion" means that it is a coefficient of linear expansion in the direction perpendicular to the film surface calculated by the above formula (1). .

The agricultural film which has the above-mentioned coefficient of linear expansion can be manufactured by adjusting the conditions of a raw material and a manufacturing method suitably. The resin composition used as a general raw material of an agricultural film can be used for the layer which consists of a continuous phase and a dispersed phase contained in an agricultural film (and layers other than the layer which consists of a continuous phase and a dispersed phase). As a raw material for the layer consisting of the continuous phase and the dispersed phase, in particular, at least one selected from a thermoplastic resin serving as the continuous phase, organic particles serving as the dispersed phase, inorganic particles, and a thermoplastic resin different from the thermoplastic resin of the continuous phase is appropriately combined. You can use it. In addition, when the dispersed phase is a thermoplastic resin different from the continuous phase thermoplastic resin, the layer comprising the continuous phase and the dispersed phase has a sea-island structure in which the continuous phase and the dispersed phase thermoplastic resin are phase-separated. The part of the sea-island structure becomes a thermoplastic resin used as a continuous phase, and the part of the figure becomes a thermoplastic resin used as a dispersed phase. A more preferable raw material for a layer comprising a continuous phase and a dispersed phase will be described later in [Layer comprising a continuous phase and a dispersed phase]. As a raw material for layers other than the layer consisting of the continuous phase and the dispersed phase, a general thermoplastic resin may be used, and a polyolefin-based resin is preferably used. also called). The conditions of a more preferable manufacturing method are mentioned later in <The manufacturing method of an agricultural film>.

(Haze value)

In addition, in this specification, a haze value is a value measured using the temperature control haze meter (THM-150TL) made by Murakami Color Technology Research Institute based on JISK7136:2000 for measurement conditions other than temperature. In the present specification, the light scattering property of the film may be evaluated by the haze value.

It is preferable that haze value in 40 degreeC is 45 % or more, and, as for the agricultural film which concerns on one aspect of this invention, it is more preferable that it is 50 % or more. When the haze value in 40 degreeC is 45 % or more, the summer with much solar radiation WHEREIN: The light irradiated to a film can be preferably scattered.

Moreover, in the agricultural film which concerns on one aspect of this invention, the difference of the haze value in 0 degreeC and the haze value in 40 degreeC is, for example, 30 % or more, More preferably, it is 35 % or more, The haze value in 40 degreeC shows the higher value than the haze value in 0 degreeC. Accordingly, it is possible to prevent the light irradiated to the film from scattering in the winter season with a small amount of insolation.

(1% fixed elastic modulus)

The elastic modulus to be determined at 1% is measured using a test piece cut out of the film to a width of 20 mm and a length of 125 mm. In addition, in this specification, the elastic modulus to be set to 1% (1% Secant Modulus, hereinafter abbreviated as 1% SM) is attached to a tensile tester (eg, Shimadzu Corporation, AGS-100B) at a distance between chucks of 5 cm. , It is a value computed by following formula (2) from the load value at the time of 1% elongation measured by pulling at the speed|rate of 5 mm/min.

1% SM = F/S/0.01 (2)

Here, F is the load at the time of 1% elongation of the test piece, and S represents the initial area of the cross section perpendicular to the tensile direction of the test piece. In addition, the initial area is the area before implementing a tensile test.

As for the agricultural film which concerns on one aspect of this invention, it is preferable that 1% SM is larger than 18 Mpa, It is more preferable that it is 20 Mpa or more, It is more preferable that it is 22 Mpa or more.

From a viewpoint of ensuring the light scattering property in the summer reaching|attaining 40 degreeC vicinity, it is preferable that the thickness of a film is 1 micrometer or more, More preferably, it is 30 micrometers or more. It is preferably 500 µm or less, and more preferably 300 µm or less, from the viewpoint of lowering light scattering properties and improving handling properties by reducing the weight of the film in the winter season approaching 0°C. In addition, the thickness of the film described in this paragraph is the thickness of the film that can be measured at about room temperature (23 ° C), and L _{25 ° C. and L 0 °} C. in the formula (1) for obtaining the coefficient of linear expansion are necessarily consistent with it is not

[Layer composed of continuous phase and dispersed phase]

The layer composed of the continuous phase and the dispersed phase is the main layer constituting the agricultural film according to one aspect, and is simply described as a “layer” in the present specification. It shows that it is a layer which consists of a dispersed phase.

In the cross section of the film cut in the direction perpendicular to the film surface and parallel to the slow axis in the plane of the film, the agricultural film according to one aspect of the present invention has an equivalent circle diameter of 1 µm or more and 10 µm in the dispersed phase. It is preferable that they are 1 % or more and 30 % or less with respect to the area of the cross section of a layer, and, as for the ratio of the area of the cross section of the dispersed phase or less, it is more preferable that they are 2 % or more and 25 % or less. In addition, the in-plane slow axis of the said film can be calculated|required using the phase difference measuring apparatus (KOBRA (trademark) series by Oji Instruments Co., Ltd. series etc.) which uses the parallel Nicol rotation method as a measurement principle. When the ratio of the area of the cross-section of the dispersed phase having an equivalent circle diameter of 1 µm or more and 10 µm or less is within the range of 1% or more and 30% or less, light scattering property is improved in the summer when reaching 40°C, and light scattering property in the winter reaching around 0°C. can be made lower.

In the present specification, the dispersed phase means a phase composed of at least one selected from organic particles dispersed in a continuous phase, inorganic particles, and a thermoplastic resin different from the continuous phase thermoplastic resin. The equivalent circle diameter of the dispersed phase means the equivalent circle diameter of the dispersed phase obtained for each observed dispersed phase. In addition, the shape of a dispersed phase is not specifically limited. Here, "circle-equivalent diameter" means the diameter of a circle having the same area as the cross-sectional area of one dispersed phase reflected on the cross-section of the photographed layer, and can be obtained from the image obtained by photographing the cross-section of the agricultural film by the image analysis system .

In the resin composition constituting the layer composed of the continuous phase and the dispersed phase, the mixing ratio of the component constituting the continuous phase and the component constituting the dispersed phase has a coefficient of linear expansion of 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^{− It} adjusts appropriately so that it may become 1 or less. For example, as the ratio of the dispersed phase in the layer comprising the continuous phase and the dispersed phase is decreased, the coefficient of linear expansion can be adjusted to become higher, and the coefficient of linear expansion can be adjusted to become lower as the ratio of the dispersed phase is made higher.

When the total amount of the component constituting the continuous phase and the component constituting the dispersed phase is 100 parts by mass, the content of the component constituting the continuous phase is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, More preferably, it is 65 mass parts or more, Especially preferably, it is 70 mass parts or more. Moreover, content of the component which comprises a continuous phase becomes like this. Preferably it is 98 mass parts or less, More preferably, it is 95 mass parts or less, More preferably, it is 90 mass parts or less, Especially preferably, it is 85 mass parts or less. .

In addition, when the total amount of the component constituting the continuous phase and the component constituting the dispersed phase is 100 parts by mass, the content of the component constituting the dispersed phase is preferably 2 parts by mass or more, more preferably 5 parts by mass or more. , More preferably, it is 10 mass parts or more, Especially preferably, it is 15 mass parts or more. Moreover, Preferably it is 50 mass parts or less, More preferably, it is 40 mass parts or less, More preferably, it is 35 mass parts or less, Especially preferably, it is 30 mass parts or less. When the content of the component constituting the dispersed phase is 50 parts by mass or less, sufficient elongation and breaking strength can be ensured. As the content of the component constituting the dispersed phase is decreased, the coefficient of linear expansion can be adjusted to be higher, and as the content of the component constituting the dispersed phase is increased, the coefficient of linear expansion can be made lower.

[Continuous Award]

It is preferable that a continuous phase contains a thermoplastic resin. The thermoplastic resin may be any thermoplastic resin capable of forming a portion corresponding to a solution in the sea-island structure, and is not limited, but it is preferable that the coefficient of linear expansion is larger than that of the component used to form the dispersed phase. In order to adjust the coefficient of linear expansion of the layer which consists of a continuous phase and a dispersed phase to the above-mentioned range, as a more preferable thermoplastic resin, a polyolefin resin is mentioned. As polyolefin-type resin, an ethylene-type copolymer, a propylene-type polymer, etc. are mentioned, for example.

(Ethylene-based copolymer)

Examples of the ethylene-based copolymer include an ethylene-vinyl ester copolymer, a copolymer of ethylene and an unsaturated carboxylic acid and/or a derivative thereof (hereinafter also referred to as an ethylene-unsaturated carboxylic acid (derivative) copolymer), ethylene -α-olefin copolymer etc. are mentioned. An ethylenic copolymer may be used independently and may use 2 or more types of ethylene-type copolymer together.

The ethylene-vinyl ester copolymer refers to an ethylene-vinyl ester copolymer having, as main monomer units, a monomer unit derived from ethylene and a monomer unit derived from a vinyl ester. The ethylene-vinyl ester copolymer may be a random copolymer of a monomer derived from ethylene and a monomer derived from a vinyl ester, or may be a block copolymer.

As a vinyl ester used as a constituent material of an ethylene-vinyl ester copolymer, it is a vinyl ester of a fatty acid, for example, and the C2-C4 thing of the said fatty acid is mentioned, More specifically, vinyl acetate and vinyl propionate. and the like. In one aspect of the present invention, the ethylene-vinyl ester copolymer may include monomer units derived from two or more types of vinyl esters. Especially, it is preferable that vinyl ester is vinyl acetate.

Specific examples of the ethylene-vinyl ester copolymer having a monomer unit derived from ethylene and a monomer unit derived from a vinyl ester include an ethylene-vinyl acetate copolymer, and an ethylene-vinyl propionate copolymer. In particular, ethylene -Vinyl acetate copolymer (EVA) is used preferably. Moreover, an ethylene-vinyl ester copolymer may be used independently and may use 2 or more types of ethylene-vinyl ester copolymer together.

Moreover, the ethylene-vinyl ester copolymer may contain the monomeric unit derived from monomers other than ethylene and vinyl ester.

Commercial products usable as the ethylene-vinyl ester copolymer include, for example, Evatate (registered trademark) (manufactured by Sumitomo Chemical Co., Ltd.), and Sumitate (registered trademark) (manufactured by Sumitomo Chemical Co., Ltd.), Novatec (registered trademark) EVA (manufactured by Nippon Polyethylene Co., Ltd.), Ultrasen (registered trademark) (manufactured by Toso Corporation), Santec (registered trademark) EVA (manufactured by Asahi Chemical Co., Ltd.), EVAFlex (registered trademark) (manufactured by Mitsui DuPont Polychemical Corporation), etc. can be heard

In the ethylene-vinyl ester copolymer, the content of the monomer unit derived from the vinyl ester is preferably 7 mass% or more and 30 mass% or less, more preferably 10 mass% or more and 28 mass% or less, still more preferably is 12 mass% or more and 25 mass% or less.

Further, in the ethylene-vinyl ester copolymer, the content of the monomer unit derived from ethylene is preferably 70 mass% or more and 93 mass% or less, more preferably 72 mass% or more and 90 mass% or less, and still more preferably Preferably, it is 75 mass % or more and 88 mass % or less.

When two or more types of ethylene-vinyl ester copolymers are used together as an ethylene-vinyl ester copolymer, content E of the monomeric unit derived from ethylene in a copolymer is computed by following formula (3).

E (mass%) = (E ₁ W ₁ + E ₂ W ₂ + … + E _m W _m )/(W ₁ + W ₂ + … W _m ) (3)

(However, ethylene-vinyl ester copolymer 1, ethylene-vinyl ester copolymer 2, ... ethylene-vinyl ester copolymer m of m types of ethylene-vinyl ester copolymers are used together (m is an integer of 3 or more), Let the content (mass %) of the monomer unit derived from ethylene in the ethylene-vinyl ester copolymer k be E _k , and the content of the ethylene-vinyl ester copolymer k in the resin composition _{be W k} (k is from 1 to m of integers).)

Similarly, when two or more types of ethylene-vinyl ester copolymers are used together as an ethylene-vinyl ester copolymer, the content E' of the monomer unit derived from the vinyl ester in the copolymer is obtained by the following formula (4) is calculated

E' (mass%) = (E' ₁ W ₁ + E' ₂ W ₂ + ... + E' _m W _m )/(W ₁ + W ₂ + ... W _m ) (4)

(However, copolymer 1, copolymer 2, ... copolymer of m types of copolymer m is used together (m is an integer of 3 or more), and the content of the monomer unit derived from the vinyl ester in the copolymer k ( Let E' _k and content of copolymer k in the resin composition _{be W k} (k is an integer from 1 to m).

In addition, content of the monomeric unit derived from ethylene in an ethylene-vinyl ester copolymer, and content of the monomeric unit derived from vinyl ester can be quantified by the saponification method. More specifically, when the ethylene-based copolymer is an ethylene-vinyl acetate copolymer, it can be quantified according to JIS K 7192: 1999.

The melt flow rate (MFR) of the ethylene-vinyl ester copolymer is preferably 0.05 g/10 min or more and 20 g/10 min or less, and more preferably 0.1 g/10 min or more and 15 g/10 min or less. . The said MFR is measured by A method according to JISK7210:1999 under the conditions of a temperature of 190 degreeC, and a load of 21.18 N.

The ethylene-unsaturated carboxylic acid (derivative) copolymer is an ethylene-unsaturated carboxylic acid (derivative) copolymer having, as main monomers, a monomer unit derived from ethylene and a monomer unit derived from an unsaturated carboxylic acid and/or a derivative thereof. say The ethylene-unsaturated carboxylic acid (derivative) copolymer may be a random copolymer of a monomer derived from ethylene and a monomer derived from an unsaturated carboxylic acid and/or a derivative thereof, or may be a block copolymer.

As an unsaturated carboxylic acid used as a constituent material of an ethylene- unsaturated carboxylic acid (derivative) copolymer, Unsaturated monocarboxylic acids, such as (meth)acrylic acid, a crotonic acid, an isocrotonic acid, 3-butenoic acid; Although unsaturated dicarboxylic acids, such as a maleic acid and a fumaric acid, are mentioned, It is not limited to these. Among these, an unsaturated monocarboxylic acid is preferable, for example, (meth)acrylic acid is preferable. In addition, in this specification, acrylic acid and methacrylic acid are generically referred to as (meth)acrylic acid.

Examples of the unsaturated carboxylic acid derivative used as a constituent material of the ethylenically-unsaturated carboxylic acid (derivative) copolymer include a salt of the above unsaturated carboxylic acid, an unsaturated carboxylic acid ester, an acid anhydride, an unsaturated carboxylic acid amide, and an unsaturated carboxylic acid. Acid imide etc. are mentioned, Preferably they are the salt of unsaturated carboxylic acid, and unsaturated carboxylic acid ester. As a salt of an unsaturated carboxylic acid, a sodium salt, potassium salt, a calcium salt, a zinc salt, etc. of an unsaturated carboxylic acid are mentioned. As unsaturated carboxylic acid ester, Unsaturated carboxylic acid alkyl esters, such as unsaturated carboxylic acid methyl ester, unsaturated carboxylic acid ethyl ester, and unsaturated carboxylate butyl ester; Unsaturated carboxylic acid aryl esters, such as unsaturated carboxylic acid phenyl ester; Unsaturated carboxylic acid glycidyl ester etc. are mentioned.

Specific examples of the ethylene-unsaturated carboxylic acid (derivative) copolymer having a monomer unit derived from ethylene in the present invention and a monomer unit derived from an unsaturated carboxylic acid and/or a derivative thereof include ethylene-(meth)acrylic acid Ethylene-unsaturated carboxylic acid copolymers, such as a copolymer; an ionomer obtained by neutralizing a part or all of the carboxyl groups of an ethylene-unsaturated carboxylic acid copolymer such as an ethylene-(meth)acrylic acid copolymer with a metal ion such as sodium, potassium, calcium or zinc; and ethylene-unsaturated carboxylic acid ester copolymers such as ethylene-(meth)methyl acrylate copolymer, ethylene-(meth)ethyl acrylate copolymer, and ethylene-(meth)butyl acrylate copolymer. In particular, ethylene-( A meth)acrylic acid copolymer, an ethylene- (meth)methyl acrylate copolymer, an ethylene- (meth)ethyl acrylate copolymer, etc. are used preferably. Further, in one aspect of the present invention, the ethylene-unsaturated carboxylic acid (derivative) copolymer may include monomer units derived from two or more types of unsaturated carboxylic acids and/or derivatives thereof.

Specific examples of the ethylene-unsaturated carboxylic acid (derivative) copolymer include the following.

(i) ethylene-unsaturated carboxylic acid copolymer

Nucrel (registered trademark) (ethylene-methacrylic acid copolymer, manufactured by Mitsui DuPont Polychemical Co., Ltd.)

(ii) an ionomer in which some or all of the carboxyl groups of the ethylene-unsaturated carboxylic acid copolymer are neutralized with metal ions

Hymilan (registered trademark) (Ionomer obtained by neutralizing some of the carboxyl groups of the ethylene-methacrylic acid copolymer with zinc ions or sodium ions, manufactured by Mitsui DuPont Polychemicals Co., Ltd.)

(iii) ethylene-unsaturated carboxylic acid ester copolymer

Acrift (registered trademark) (ethylene-methyl methacrylate copolymer, manufactured by Sumitomo Chemical Co., Ltd.), Rexpearl (registered trademark) EMA (ethylene-methyl acrylate copolymer, manufactured by Nippon Polyethylene Co., Ltd.), Rexpearl (registered trademark) EEA (Ethylene-ethyl acrylate copolymer, manufactured by Nippon Polyethylene Co., Ltd.), Lautril (registered trademark) (ethylene-methyl acrylate copolymer or ethylene-butyl acrylate copolymer, manufactured by Alkema Corporation), Elvaroi (registered trademark) AC (ethylene- Any of methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate copolymer, manufactured by DuPont)

The ethylene-unsaturated carboxylic acid (derivative) copolymer may be used independently and may use together 2 or more types of ethylene- unsaturated carboxylic acid (derivative) copolymer.

Content of the monomeric unit derived from the unsaturated carboxylic acid and/or its derivative(s) in an ethylene-unsaturated carboxylic acid (derivative) copolymer is the rigidity of a film, and the light scattering property accompanying a temperature change (0 degreeC - 40 degreeC) From the balance of change of (haze value), Preferably it is more than 10 mass % and 40 mass % or less, More preferably, it is 15 mass % or more and 35 mass % or less, More preferably, it is 20 mass % or more and 30 mass % or less. (However, the mass of the ethylene-unsaturated carboxylic acid (derivative) copolymer is 100 mass%).

Content of the monomeric unit derived from the unsaturated carboxylic acid and/or its derivative(s) in an ethylenically unsaturated carboxylic acid (derivative) copolymer can be measured by the infrared absorption spectrum analysis method.

The content of the monomer unit derived from ethylene in the ethylene-unsaturated carboxylic acid (derivative) copolymer is a balance between the stiffness of the film and the change in light scattering properties (haze value) accompanying a temperature change (0°C to 40°C) From Let the mass of the acid (derivative) copolymer be 100 mass%).

The content of the monomer unit derived from ethylene in the ethylene-unsaturated carboxylic acid (derivative) copolymer is 100, the content of the monomer unit derived from the unsaturated carboxylic acid and/or its derivative measured by infrared absorption spectrum analysis. It is computable by subtracting from mass %.

When two or more types of ethylene-unsaturated carboxylic acid (derivative) copolymers are used together as the ethylene-unsaturated carboxylic acid (derivative) copolymer, the content E of the monomer unit derived from ethylene in the copolymer is obtained by the following formula ( 5) is calculated by

E" (mass%) = (E" ₁ W' ₁ + E" ₂ W' ₂ + ... + E" _m W' _m )/(W' ₁ + W' ₂ + ... W' _m ) (5)

(with the proviso that ethylene-unsaturated carboxylic acid (derivative) copolymer 1, ethylene-unsaturated carboxylic acid (derivative) copolymer 2, ... ethylene-unsaturated carboxylic acid (derivative) of m species of ethylene-unsaturated carboxylic acid (derivative) copolymer m Let the acid (derivative) copolymer be used together (m is an integer of 2 or more), and the content of the ethylene-derived monomeric unit in the ethylene-unsaturated carboxylic acid (derivative) copolymer k is E" _k , the resin composition Let the content of copolymer k in W' _k be (k is an integer from 1 to m).

The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid (derivative) copolymer is preferably 0.1 g/10 min or more and 10 g/10 min or less from the viewpoint of processing into a film form. The MFR is measured by method A or method B in accordance with JIS K7120:1999 under conditions of a temperature of 190°C and a load of 21.18 N.

The ethylene-α-olefin copolymer refers to an ethylene-α-olefin copolymer having, as main monomers, a monomer unit derived from ethylene and a monomer unit derived from an α-olefin. The ethylene-α-olefin copolymer may be a random copolymer of a monomer derived from ethylene and a monomer derived from an α-olefin, or may be a block copolymer.

The content of the monomer unit derived from ethylene in the ethylene-α-olefin copolymer is preferably 50 mass% or more and 90 mass% or less, more preferably 55 mass% or more and 85 mass% or less, still more preferably is 60 mass% or more and 80 mass% or less (provided that the mass of the ethylene-α-olefin copolymer is 100 mass%).

The monomer derived from the α-olefin preferably has 3 to 20 carbon atoms, and the ethylene-α-olefin copolymer includes, for example, an ethylene-1-butene copolymer, an ethylene-1-pentene copolymer, An ethylene-1-hexene copolymer, an ethylene-1-heptene copolymer, an ethylene-1-octene copolymer, etc. are mentioned. Among these, an ethylene-1-butene copolymer, an ethylene-1-hexene copolymer, and an ethylene-1-octene copolymer are particularly preferable. Moreover, an ethylene-propylene copolymer may be sufficient as content of the monomeric unit derived from ethylene is 50 mass % or more. As the ethylene-α-olefin copolymer, a copolymer obtained by copolymerizing ethylene and two or more types of α-olefins may be used.

The ethylene-α-olefin copolymer contributes to the provision of a film having excellent strength. From the viewpoint of obtaining a film having high strength, the ethylene-α-olefin copolymer is preferably one in which ethylene and α-olefin are polymerized using a metallocene catalyst.

The following are mentioned as a commercial item usable as said ethylene-alpha-olefin copolymer. Exelene (registered trademark) FX (manufactured by Sumitomo Chemical Co., Ltd.), TAPMER (registered trademark) (manufactured by Mitsui Chemical Corporation), ENGAGE (registered trademark) (manufactured by Dow Chemical), AFFINITY (registered trademark) (manufactured by Dow Chemical), EXACT (trademark) (manufactured by ExxonMobil), Kernel (registered trademark) (manufactured by Nippon Polyethylene Co., Ltd.).

As the ethylene-α-olefin copolymer, an individual ethylene-α-olefin copolymer may be used, or two or more types of ethylene-α-olefin copolymers may be used in combination.

(Propylene-based polymer)

Examples of the propylene-based polymer include a propylene homopolymer, a copolymer of propylene and ethylene and/or an α-olefin having 4 or more carbon atoms, and among these, a copolymer of propylene and ethylene and/or an α-olefin having 4 or more carbon atoms is preferable. do.

The content of the monomer unit derived from propylene in the copolymer of propylene and ethylene and/or an α-olefin having 4 or more carbon atoms is preferably 70 mass% or more and 99 mass% or less (however, propylene and ethylene and/or or the mass of the copolymer of α-olefin having 4 or more carbon atoms is 100 mass%).

When the propylene polymer is a copolymer of propylene and ethylene and/or an α-olefin having 4 or more carbon atoms, the content of monomer units derived from ethylene and/or an α-olefin having 4 or more carbon atoms is preferably 1 mass% or more and 30 mass % or less (however, the mass of the copolymer of propylene and ethylene and/or an ?-olefin having 4 or more carbon atoms is 100 mass%).

The melt flow rate (MFR) of the propylene polymer is preferably 0.05 g/10 min or more and 20 g/10 min or less, and more preferably 0.1 g/10 min or more and 15 g/10 min or less. The MFR is measured by method A according to JIS K 7120:1999 under conditions of a temperature of 230°C and a load of 21.18 N.

The continuous phase may contain, in addition to the thermoplastic resin, at least one additive selected from a light stabilizer, an ultraviolet absorber, an antifogging agent, an antioxidant, an antifog agent, a lubricant, and the like within a range that does not impair the effects of the present invention.

[dispersed phase]

It is preferable that a dispersed phase contains at least 1 component selected from the thermoplastic resin different from the thermoplastic resin of organic type particle|grains, inorganic type particle|grains, and a continuous phase. In the agricultural film according to one aspect of the present invention, the coefficient of linear expansion can be adjusted so that the ratio of the dispersed phase having a circle equivalent diameter of 1 µm or more and 10 µm or less in the layer comprising the continuous phase and the dispersed phase is lowered to become higher. Moreover, it can adjust so that a coefficient of linear expansion may become lower, so that the dispersed phase ratio of 1 micrometer or more and 10 micrometers or less of equivalent circle diameter is made high. It has already been described that the coefficient of linear expansion ^{can be adjusted to be 1.5 × 10 -4} K ^-1 or more and 2.8 × 10 ^-4 K ^{-1 or less.} In addition, the component of the dispersed phase in the layer which consists of a continuous phase and a dispersed phase may be any of organic particle|grains, inorganic type particle|grains, and a thermoplastic resin different from the thermoplastic resin of a continuous phase. The refractive index of the component included in the dispersed phase is not particularly limited, but is preferably 1.50 or more and 1.53 or less, more preferably 1.50 or more and lower than 1.53, still more preferably 1.51 or more and 1.52 or less, and most preferably 1.51 or more and 1.52 or less. do. The refractive index of the component contained in the dispersed phase is 1.50 or more and 1.53 or less, and the linear expansion coefficient is within the above-mentioned range, so that the light scattering property of the film is increased in the summer when the temperature reaches 40 ° C. By making the scattering property low, the difference in the light scattering property depending on the difference in temperature can be increased. In addition, the said refractive index is the value measured using the particle|grain immersion method at room temperature, Here, the 3rd decimal place or less in the value of a refractive index is rounded off.

(organic particles)

As organic particle|grains, crosslinked acrylic particle|grains are mentioned, for example. Examples of the crosslinked acrylic particles include crosslinked copolymer particles of (meth)acrylic acid ester and styrene (crosslinked MMA-St copolymer particles). As (meth)acrylic acid ester, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, etc. are mentioned, Preferably methyl acrylate, methyl methacrylate, or methacryl It is butyl acid, More preferably, it is methyl methacrylate.

The crosslinked copolymer particles of (meth)acrylic acid ester and styrene may be crosslinked copolymer particles containing only monomer units derived from (meth)acrylic acid ester and styrene, and may be particles other than monomer units derived from (meth)acrylic acid ester and styrene. A crosslinked copolymer particle containing a monomer unit may be sufficient. Moreover, in the said (meth)acrylic acid ester and styrene crosslinked copolymer particle|grains, it is preferable that the content rate of the monomeric unit derived from (meth)acrylic acid ester and styrene which occupies for all monomer units is 80 mass % or more.

The content of the (meth)acrylic acid ester-derived monomer unit in the crosslinked copolymer particles of (meth)acrylic acid ester and styrene is preferably 50 to 99 mass%, more preferably 60 to 90 mass% . Moreover, content of the monomeric unit derived from styrene in the crosslinked copolymer particle of the said (meth)acrylic acid ester and styrene becomes like this. Preferably it is 1-50 mass %, More preferably, it is 10-40 mass %. (However, the sum total of the monomeric unit derived from (meth)acrylic acid ester, and the monomeric unit derived from styrene shall be 100 mass %.)

The particles of the crosslinked copolymer of (meth)acrylic acid ester and styrene are prepared by subjecting at least one selected from (meth)acrylic acid ester, styrene, and, if necessary, a monomer component comprising another monomer to a known method such as suspension polymerization. It can be obtained by polymerization by

As a method of obtaining crosslinked acrylic particle|grains, the method of suspension-polymerizing a monomer component with a crosslinking agent is mentioned. As the crosslinking agent, it is preferable to use a compound having two or more unsaturated groups, and specifically, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, divinylbenzene, and the like are mentioned. can

The volume median diameter of the organic particles is preferably 1 µm or more, more preferably 2 µm or more, and still more preferably 3 µm or more from the viewpoint of increasing light scattering properties in the summer reaching around 40°C. Moreover, the said volume median diameter becomes like this. Preferably it is 10 micrometers or less, More preferably, it is 8 micrometers or less, More preferably, it is 6 micrometers or less. The volume median diameter of organic particle|grains is measured by the Coulter counter method. In addition, in order to make the area ratio of the cross section of the dispersed phase having an equivalent circle diameter of 1 µm or more and 10 µm or less fall within the above-mentioned range, the volume median diameter of the component constituting the dispersed phase of the layer comprising the continuous phase and the dispersed phase is 1 µm or more and 10 µm or more. What is necessary is just to adjust the ratio of the following organic particle|grains. For example, the content of organic particles having a volume median diameter of 1 µm or more and 10 µm or less with respect to 100 parts by mass of the component constituting the dispersed phase of the layer consisting of the continuous phase and the dispersed phase is preferably 50 parts by mass or more, and 70 parts by mass or more It is more preferable, and it is still more preferable that it is 90 mass parts or more.

As examples of commercial products of the organic particles, Techpolymer (registered trademark) MSX series, Techpolymer (registered trademark) SSX series (above, manufactured by Sekisui Chemical Industry Co., Ltd.), Art Pearl (registered trademark) G series, Art Pearl ( Registered trademark) GS series (above, manufactured by Negami Kogyo Co., Ltd.), Gantz Pearl (registered trademark) GSM series (above, manufactured by Aika Kogyo) etc. are mentioned.

(inorganic particles)

Examples of the inorganic particles include glass particles, kaolin, and aluminosilicate (zeolite).

Glass particles are particles _{containing silicon dioxide (SiO 2} ), boron oxide (B ₂ O ₃ ), aluminum oxide (Al ₂ O ₃ ), sodium oxide (Na ₂ O), calcium oxide (CaO), and oxide At least one inorganic compound selected from the group consisting of zinc (ZnO) may be included. The glass particles may further contain additional inorganic compounds and additives as needed. Specifically, in addition to the above inorganic compounds, zirconium oxide, magnesium oxide, strontium oxide, lanthanum oxide, yttrium oxide, gadolinium oxide, bismuth oxide, antimony oxide, tantalum oxide, niobium oxide, tungsten oxide, magnesium carbonate, silicon nitride , aluminum nitride, aluminum oxynitride, magnesium fluoride, calcium fluoride, sodium fluoride, lithium fluoride, iron, and other common inorganic compounds as necessary are mixed appropriately to prepare an agricultural film within the range of the coefficient of linear expansion described above. have.

The shape of each inorganic particle is not particularly limited, and inorganic particles of various shapes such as spherical (eg, glass bead), fibrous (eg, chopped fiber, milled fiber), and flake shape can be used. .

When the inorganic particles are spherical, their volume median diameter is preferably 1 µm or more, more preferably 2 µm or more, and still more preferably 3 µm from the viewpoint of increasing light scattering properties in the summer reaching around 40°C. More than that. Moreover, the said volume median diameter becomes like this. Preferably it is 10 micrometers or less, More preferably, it is 8 micrometers or less, More preferably, it is 6 micrometers or less. The volume median diameter of a particle is measured by the laser diffraction method. In addition, in order to make the area ratio of the cross section of the dispersed phase having an equivalent circle diameter of 1 µm or more and 10 µm or less fall within the above-mentioned range, the volume median diameter of the component constituting the dispersed phase of the layer comprising the continuous phase and the dispersed phase is 1 µm or more and 10 µm or more. What is necessary is just to adjust the ratio of the following inorganic type particle|grains. For example, the content of inorganic particles having a volume median diameter of 1 µm or more and 10 µm or less with respect to 100 parts by mass of the component constituting the dispersed phase of the layer consisting of the continuous phase and the dispersed phase is preferably 50 parts by mass or more, and 70 parts by mass or more It is more preferable, and it is still more preferable that it is 90 mass parts or more.

When the inorganic particles are fibrous, the aspect ratio is not particularly limited, but from the viewpoint of increasing light scattering properties in the summer reaching around 40° C., those having an aspect ratio of 1 to 500 are used, and those having an aspect ratio of 1 to 100 are more preferably used. , an aspect ratio of 1 to 50 is more preferably used.

In addition, the inorganic particle may be surface-treated with surface treatment agents, such as a coupling agent.

(The thermoplastic resin of the dispersed phase different from the thermoplastic resin of the continuous phase)

The thermoplastic resin that can be included in the dispersed phase may be any thermoplastic resin capable of forming a portion corresponding to the degree in the sea-island structure in the thermoplastic resin serving as the continuous phase, and a thermoplastic resin having a smaller coefficient of linear expansion than the thermoplastic resin used in the continuous phase. It is preferable to use a resin. When an olefin resin is used for the thermoplastic resin used as a continuous phase, for example, polyvinyl alcohol (PVOH), non-crosslinked acrylic resin such as polymethyl methacrylate, methyl methacrylate-phenyl methacrylate copolymer, etc. , a cyclic olefin copolymer (COC), and the like.

The dispersed phase is an infrared absorber, a light stabilizer, an ultraviolet absorber, an antifogging agent, and an oxidation phase within a range that does not impair the effects of the present invention, other than at least one selected from organic particles, inorganic particles, and a thermoplastic resin different from the continuous phase. At least one additive selected from an inhibitor, an antifouling agent, and a lubricant may be included.

As said infrared absorber, a hydrotalcite compound and lithium aluminum composite hydroxide are mentioned. Specific examples of the hydrotalcite compound include natural hydrotalcite and trade names: DHT-4A (manufactured by Kyowa Chemical Industry Co., Ltd.), Magcria (manufactured by Toda Kogyo Co., Ltd.), Magcera (registered trademark) 1 (Kyowa Chemical Industry Co., Ltd.) Chemical Industry Co., Ltd. make), Star Bace (trademark) HT-P (made by Sakai Chemical Industry Co., Ltd.), etc. are mentioned. Specific examples of the lithium-aluminum composite hydroxide include OPTIMA-SS (manufactured by Toda Kogyo Co., Ltd.) and Mizukarak (registered trademark) (manufactured by Mizusawa Chemical Industry Co., Ltd.).

In one embodiment of the present invention, the hydrotalcite compound may be used alone, or the lithium aluminum composite hydroxide may be used alone. Or you may use both together.

As said light stabilizer, the hindered amine compound which has the structure of Unexamined-Japanese-Patent No. 8-73667 is mentioned, for example. Specifically, trade names: Tinuvin (registered trademark) 622, Kimasorb (registered trademark) 944, Kimasorb (registered trademark) 119 (above manufactured by BASF), Hostabine (registered trademark) N30, Hostabine (registered trademark) ) PR-31 (above, manufactured by Clariant), Saiyasorb (registered trademark) UV3529, Saiyasorb (registered trademark) UV3346 (above, manufactured by Cytec), and the like.

Furthermore, the hindered amine compound which has the structure of Unexamined-Japanese-Patent No. 11-315067, Unexamined-Japanese-Patent No. 2001-139821, WO2005/082852, and Unexamined-Japanese-Patent No. 2009-530428 is mentioned. Specifically, trade names: NOR371 (manufactured by BASF), ADEKA STAB (registered trademark) LA-900 (manufactured by ADEKA Corporation), ADEKASTAVE (registered trademark) LA-81 (manufactured by ADEKA Corporation), Hostabine (registered trademark) NOW (manufactured by Clariant Co., Ltd.) is mentioned.

Moreover, as a light stabilizer, the ethylene-cyclic aminovinyl compound copolymer which has a monomeric unit based on ethylene and a monomeric unit based on a cyclic aminovinyl compound is also mentioned. Examples of such an ethylene-cyclic aminovinyl compound copolymer include those having the structure described in Japanese Patent Application Laid-Open No. 2002-265693.

0.01-3 mass % is preferable, as for content of the light stabilizer contained in the resin composition which comprises the layer which consists of a continuous phase and a dispersed phase, 0.05-2 mass % is more preferable, 0.1-1 mass % is especially preferable. However, the mass of the resin composition shall be 100 mass %.

Examples of the ultraviolet absorber include 2-hydroxybenzophenones, 2-(2'-hydroxyphenyl)benzotriazoles, benzoates, substituted oxanilides, cyanoacrylates, triazines, and the like. can be heard

Examples of the 2-hydroxybenzophenones include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5, 5'-methylenebis(2-hydroxy-4-methoxybenzophenone) etc. are mentioned.

Examples of 2-(2'-hydroxyphenyl)benzotriazoles include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxyl-3',5'-di Tertiary butylphenyl)benzotriazole, 2-(2'-hydroxyl-3',5'-di-tertiary butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxyl-3'- Tertiary butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-tertiary octylphenyl)benzotriazole, 2-(2'-hydroxyl-3', 5'-dicumylphenyl)benzotriazole, 2-(2-hydroxy-3,5-ditertiary pentylphenyl)benzotriazole, 2,2'-methylenebis(4-tertiary octyl-6-benzo triazolyl)phenol, 2-(2'-hydroxy-3'-tertiary butyl-5-carboxyphenyl)benzotriazole, etc. are mentioned.

Benzoates include phenyl salicylate, resorcinol monobenzoate, 2,4-ditertiary butylphenyl-3',5'-ditertiary butyl-4'-hydroxybenzoate, 2,4 -ditertiary amylphenyl-3',5'-ditertiary butyl-4'-hydroxybenzoate, hexadecyl-3,5-ditertiary butyl-4-hydroxybenzoate, etc. are mentioned.

As substituted oxanilides, 2-ethyl-2'-ethoxyoxanilide, 2-ethoxy-4'- dodecyloxanilide, etc. are mentioned.

Examples of the cyanoacrylates include ethyl-α-cyano-β,β-diphenyl acrylate and methyl-2-cyano-3-methyl-3-(p-methoxyphenyl)acrylate. have.

Examples of the triazines include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol, 2-[4,6-bis(2) ,4-Dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)phenol, 2-(2-hydroxy-4-octoxyphenyl)-4,6-bis( 2,4-ditertiary butylphenyl)-s-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-s-triazine, 2-(2-hydroxyl -4-propoxy-5-methylphenyl)-4,6-bis(2,4-di tertiary butylphenyl)-s-triazine etc. are mentioned.

Preferably, they are 2-(2'-hydroxyphenyl) benzotriazoles, More preferably, 2-(2'-hydroxy-3'-tertiary butyl-5'-methylphenyl)-5-chlorobenzo triazole and 2-(2-hydroxy-3,5-ditertiary pentylphenyl)benzotriazole are mentioned.

A ultraviolet absorber is used individually or in 2 or more types. 0.001-3 mass % is preferable and, as for content of the ultraviolet absorber contained in the resin composition which comprises the layer which consists of a continuous phase and a dispersed phase, 0.005-1 mass % is more preferable. However, the mass of the resin composition shall be 100 mass %.

Examples of the antifogging agent include sorbitan fatty acid esters such as sorbitan monopalmitate, sorbitan monostearate, sorbitan monopalmitate, sorbitan monomontanate, sorbitan monooleate and sorbitan dioleate, and alkylenes thereof. Sorbitan surfactants such as oxide adducts, glycerin monopalmitate, glycerin monostearate, diglycerin distearate, triglycerin monostearate, tetraglycerin dimontanate, glycerin monooleate, diglycerin monooleate, Glycerin fatty acid esters and alkyls thereof, such as diglycerin sesquioleate, tetraglycerin monooleate, hexaglycerin monooleate, hexaglycerin trioleate, tetraglycerin trioleate, tetraglycerin monolaurate, and hexaglycerin monolaurate Glycerin-based surfactants such as renoxide adducts, polyethylene glycol-based surfactants such as polyethylene glycol monopalmitate and polyethylene glycol monostearate, alkylene oxide adducts of alkylphenols, sorbitan/glycerin condensates and esters of organic acids; Polyoxyethylene (2 moles) stearylamine, polyoxyethylene (4 moles) stearylamine, polyoxyethylene (2 moles) stearylamine monostearate, polyoxyethylene (4 moles) laurylamine monostearate, etc. Nonionic surfactants, such as polyoxyethylene alkylamine and its fatty acid ester, are mentioned. These may be used independently and may use 2 or more types together.

Examples of the antioxidant include so-called hindered phenol compounds such as 2,6-dialkylphenol derivatives and 2-alkylphenol derivatives, and trivalent phosphorus atoms such as phosphite compounds and phosphonite compounds. The phosphorus ester compound contained is mentioned. These antioxidants may be used independently and may use 2 or more types together. In particular, from the viewpoint of color stabilization, it is preferable to use a hindered phenol-based compound and a phosphorus-based ester compound in combination.

Examples of the antifouling agent include a fluorine compound having a perfluoroalkyl group, an ω-hydrofluoroalkyl group, etc. (especially a fluorine-based surfactant), and a silicone-based compound having an alkylsiloxane group (especially a silicone-based surfactant). have. Specific examples of the fluorine-based surfactant include Unidyne (registered trademark) DSN-403N, DS-403, DS-406, DS-401 (trade name) manufactured by Daikin Kogyo Co., Ltd., Suflon (trade name) manufactured by AGC Semichemical Co., Ltd. Registered trademark) KC-40, AF-1000, AF-2000 (trade name), etc. are mentioned, As a silicone type surfactant, SH-3746 (trade name) by Tore Dow Corning Co., Ltd. is mentioned. These may be used independently and may use 2 or more types together. 0.01-3 mass % is preferable, as for content of the antifogging agent contained in the resin composition which comprises the layer which consists of a continuous phase and a dispersed phase, 0.02-2 mass % is more preferable, 0.05-1 mass % is especially preferable. However, the mass of the resin composition shall be 100 mass %.

[Other floors]

The agricultural film which concerns on one aspect of this invention may be a film which has only the layer which consists of a continuous phase and a dispersed phase, and the film which has layers other than the layer which consists of a continuous phase and a dispersed phase may be sufficient as it. As one of the preferable aspects of the film of this invention, the multilayer film in which the intermediate|middle layer which consists of a continuous phase and a dispersed phase exists between two polyolefin resin layers is mentioned. By this layer structure, the advantage that the intensity|strength of a film can be improved is acquired.

The two polyolefin resin layers in said multilayer film may be same or different. More specifically, as a structure of said multilayer film, 2 types 3 layers, 3 types 3 layers, 3 types 4 layers, 4 types 4 layers, 4 types 5 layers, 5 types 5 layers, etc. can be illustrated.

When a multilayer film consists of 4 or more types of layers, it may have a layer different from any of the layer which consists of a continuous phase and a dispersed phase, and a polyolefin resin layer, and may have three or more layers of polyolefin resin layers. Moreover, there may be two or more layers which consist of a continuous phase and a dispersed phase.

For example, when the polyolefin-based agricultural film is a 5-layer film, the polyolefin-based resin layer is A, and the intermediate layer composed of a continuous phase and a dispersed phase is B, when a layer different from A and B is C, C/A/B/ Any of A/C, A/B/A/C/C, A/A/B/A/A, A/A/B/B/A, A/B/A/B/A, etc. may be sufficient.

Moreover, when the film which concerns on one aspect of this invention is a multilayer film which consists of three layers, as for ratio of the thickness of each layer, a linear expansion coefficient is 1.5 x 10 ^-4 K ^-1 or more and 2.8 x 10 ^-4 K ^-1 or less. to be adjusted appropriately. For example, the linear expansion coefficient can be made higher by making high the ratio of the thickness of the layer which consists of a continuous phase and a dispersed phase with respect to the thickness of the whole agricultural film. For example, when the agricultural film according to one aspect consists only of a layer consisting of a continuous phase and a dispersed phase, it is preferable to set the thickness of the film within the range of 1 μm or more and 500 μm or less as already described, but the agricultural film is a multilayer film In this case, from the viewpoint of the balance between the temperature sensitivity of 0°C and 40°C and the strength of the film, the thickness of the multilayer film is in the range of 1 µm or more and 500 µm or less, and a polyolefin-based resin layer/a layer consisting of a continuous phase and a dispersed phase It is preferable that the ratio of the thickness with / polyolefin resin layer is 1/2/1 - 1/4/1.

The polyolefin-based resin layer constituting the multilayer film contains a polyolefin-based resin. As polyolefin-type resin, the polyolefin-type resin mentioned above in [continuous phase] can be used. Polyolefin-type resin may use only 1 type and may use 2 or more types together.

The polyolefin-based resin layer may contain, if necessary, a light stabilizer, an ultraviolet absorber, an antifogging agent, an antioxidant, an antifogging agent, a lubricant, an anti-blocking agent, an antistatic agent, a pigment, etc., organic particles, inorganic particles and The layer composed of the continuous phase and the dispersed phase can be distinguished from the layer composed of the continuous phase and the dispersed phase in that it does not contain at least one component selected from a thermoplastic resin different from the thermoplastic resin of the continuous phase.

The film according to one embodiment of the present invention may have an antifogging coating layer as one surface layer or on both surfaces. As such an antifogging coating film layer, the antifogging layer which consists of an inorganic colloid, and the antifogging coating film layer containing an inorganic colloid and binder resin are mentioned.

The inorganic colloid imparts hydrophilicity to the surface of the hydrophobic polyolefin-based resin film, and is usually used in the form of a sol in which the inorganic colloid is dispersed in a liquid dispersion medium such as water. Specifically, a silica sol and an alumina sol are mentioned, A silica sol is preferable.

As binder resin, a polyurethane-type resin, an acrylic-type resin, an acrylic modified polyurethane-type resin, polyester-type resin, an epoxy resin etc. are mentioned, for example.

The binder resin is usually used as an aqueous emulsion in which the resin is dispersed in water or a mixed solvent of water and an aqueous solvent such as alcohol.

As for the antifogging coating film layer, the antifogging layer containing silica and binder resin is preferable. Moreover, as binder resin, a polyurethane-type resin, an acrylic resin, and an acrylic modified polyurethane-type resin are preferable.

As a preferable silica, the spherical thing whose average particle diameter is 5-100 nm is mentioned.

When the sum total of the silica and binder resin contained in an antifogging coating film layer is 100 mass %, content of silica is 30-70 mass %, It is preferable that content of binder resin is 30-70 mass %, content of silica It is this 50-65 mass %, and it is more preferable that content of binder resin is 35-50 mass %. When there is too little content of silica, sufficient antifogging effect cannot be acquired but conversely, when there is too much, a film may become cloudy and the light transmittance under low temperature may be reduced.

The antifogging coating layer containing silica and binder resin can be carried out, for example as shown below, and can be formed. An aqueous emulsion containing a binder resin, an aqueous silica sol containing silica, and water serving as a dispersion medium are mixed and stirred to obtain a coating solution. Next, an antifogging layer can be formed by apply|coating this coating liquid using a well-known means and drying it. Specific examples of the application means include bar coating, gravure coating, reverse coating, brush coating, spray coating, kiss coating, die coating, and dipping. As a drying means, hot air drying is mentioned, for example.

0.3-1.5 micrometers is preferable and, as for the thickness of the coating film which consists of silica and binder resin, 0.5-1.2 micrometers is more preferable.

In order to improve coatability, the said coating liquid can contain silicone type surfactant and a fluorine type surfactant. As a silicone type surfactant, polyether modified silicone oil is mentioned, for example.

Moreover, you may add a crosslinking agent, an optical stabilizer, and a ultraviolet absorber to the said coating liquid as needed.

The antifogging coating film layer may be formed as one surface layer of the said film, and may be formed as both surface layers. Moreover, a single-layer film may be sufficient as an antifogging layer, and the multilayer film of two or more layers may be sufficient as it.

<Facilities for Agricultural and Horticultural Use>

In the agricultural and horticultural facilities covered with the agricultural film according to one aspect of the present invention, the light scattering property of the film is high in the summer when the temperature reaches around 40 ° C. In addition, in winter when the temperature reaches around 0°C, the film has low light scattering properties, so that sufficient direct sunlight can be sent to the crops. It can be used throughout the year and can send a stable amount of light. The above agricultural and horticultural facilities are preferably used for cultivation of spinach, tomatoes, green onions, cucumbers, strawberries, and the like.

As an agricultural/horticultural facility provided with the agricultural film which concerns on one aspect of this invention, the greenhouse for plant cultivation, a tunnel, etc. are mentioned, for example. Agricultural and horticultural facilities WHEREIN: Said agricultural film is fully mounted in the facility frame for agricultural and horticultural use, for example.

In addition, when the agricultural film according to one embodiment of the present invention is installed in an agricultural and horticultural facility, for example, the agricultural film is caught and broken in an agricultural and horticultural facility frame for installation in an agricultural and horticultural facility. One of the advantages is that it is very easy to handle. Therefore, using the agricultural film which concerns on one aspect of this invention, the method of electric installation in an agricultural/horticultural facility, and the agricultural/horticultural facility which are fully mounted using the agricultural film are also the scope of the present invention.

[organize]

The agricultural film which concerns on the aspect 1 of this invention has at least 1 layer which consists of a continuous phase and a dispersed phase, and the following (A) and (B) are satisfied;

(A) In the cross section cut in the direction perpendicular to the film surface and parallel to the slow axis in the film plane, the ratio of the area of the cross section of the dispersed phase with the equivalent circle diameter of 1 µm to 10 µm among the dispersed phases is 1% or more and 30% or less with respect to the area of the cross-section of the layer;

(B) the coefficient of linear expansion calculated by the following formula (1) is 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less,

Coefficient of linear expansion = (L _{25 ℃} - L _{0 ℃} )/(25 ℃ - 0 ℃) (1)

Here, L _25° C represents the length of the film in the direction perpendicular to the film surface at 25°C, and L _0°C represents the length of the film in the direction perpendicular to the film surface at 0°C.

The agricultural film according to the second aspect of the present invention is the agricultural film according to the first aspect, wherein the continuous phase contains a thermoplastic resin.

Further, the agricultural film according to the third aspect of the present invention is the agricultural film according to the second aspect, wherein the thermoplastic resin is a polyolefin-based resin.

Moreover, the agricultural film which concerns on aspect 4 of this invention is an agricultural film in any one of said aspect 1-3 whose refractive index of the component contained in the said dispersed phase is 1.50 or more and 1.53 or less.

Moreover, the agricultural/horticultural facility which concerns on the 5th aspect of this invention is the agricultural/horticultural facility in which the agricultural film in any one of said aspects 1 - 4 was integrated in the agricultural/horticultural facility frame.

Example

Hereinafter, the Example of this invention is shown. In addition, the test method in an Example and a comparative example is as follows.

[Test Methods]

<Coefficient of linear expansion>

A 5 mm x 5 mm test piece was cut out from the film, set in a thermomechanical analyzer (product name: TMA402 F1 Hyperion (manufactured by NETZSCH)) set in compression mode, the load was set to 0.05 N, and the test piece was heated to -15°C. It cooled down to the following. Then, the length in the direction perpendicular|vertical to the surface in 0 degreeC and 25 degreeC, ie, thickness, was measured, heating up to 60 degreeC at a rate of 5 degreeC/min. In addition, the measurement was performed in helium atmosphere.

_{From the lengths (thickness) L 0° C.} and L _25° C. in the direction perpendicular to the surface of the test piece at 0° C. and 25° C. obtained above, the coefficient of linear expansion was calculated by the following formula (1).

Coefficient of linear expansion = (L _{25 ℃} - L _{0 ℃} )/(25 ℃ - 0 ℃) (1)

The said operation was implemented about 2 points|pieces in a film, and the average value was made into the coefficient of linear expansion of the said film.

<Ratio of the area of the cross-section of the dispersed phase with a circle equivalent diameter of 1 µm or more and 10 µm or less to the area of the cross-section of the intermediate layer>

The film was cut in a direction perpendicular to the film surface and parallel to the slow axis in the plane of the film. Using an optical microscope (the Nikon Corporation make, ECLIPSE (trademark) LV100DA-U) was used, the observation magnification was set to 500 times, and the image of two arbitrary points of the cross section of the film was acquired. The length in the direction parallel to the slow axis of the cross-sectional image of the film, described in the Examples described later, was 238 mu m equivalent to the actual dimension. In addition, the slow axis of the film was calculated|required at the wavelength of 586 nm using the retardation measuring apparatus (The Oji Instruments Co., Ltd. make, KOBRA (trademark)-WPR).

Next, using an image analysis system (manufactured by Nireco Co., Ltd., LUZEX (registered trademark)-AP), in a cross-sectional image of the film, a dispersed phase having an equivalent circle diameter with respect to the area of the cross-section of the intermediate layer of 1 µm or more and 10 µm or less The ratio of the area of a cross section (Hereinafter, it may describe as a dispersed phase ratio of 1 micrometer or more and 10 micrometers or less of an equivalent circle diameter) was calculated|required. The ratio of the dispersed phase with an equivalent circle diameter of 1 µm or more and 10 µm or less was determined for the cross-sectional images at two points, and the average value was taken as the dispersed phase ratio of the film with an equivalent circle diameter of 1 µm or more and 10 µm or less.

<Haze value>

It measured at 0 degreeC and 40 degreeC using the Murakami Color Technology Research Institute product temperature control haze meter (THM-150TL). Measurement conditions other than temperature were based on JISK7136:2000.

<1% SM> (unit: MPa)

A test piece having a width of 20 mm and a length of 125 mm was cut out, mounted on a tensile tester (manufactured by Shimadzu Corporation, AGS-100B) at a distance between chucks of 5 cm, pulled at a rate of 5 mm/min, and elongated by 1%. was calculated by the following formula (2).

1% SM = F/S/0.01 (2)

Here, F is the load at the time of 1% elongation of the test piece, and S represents the initial area of the cross section perpendicular to the tensile direction of the test piece.

In addition, about the film manufactured by the inflation molding machine, when MD direction is made into a tensile direction, and when TD direction is made into a tensile direction, measurement was performed about each.

[ingredient]

The materials used are shown below.

In addition, MFR described below corresponds to the value measured by A method or B method according to JISK7210:1999 under the conditions of the load 21.18N at predetermined temperature.

Ethylene-based copolymers:

(1) Ethylene-methyl methacrylate copolymer (hereinafter referred to as EMMA-1)

MFR (190°C, 21.18 N, method A) 7 g/10 min

Content of the monomer unit derived from ethylene 75 mass %, content of the monomer unit derived from methyl methacrylate (MMA) 25 mass % (Let the mass of EMMA-1 be 100 mass %)

(Acrift (registered trademark) WK307 manufactured by Sumitomo Chemical Co., Ltd.)

(2) Ethylene-methyl methacrylate copolymer (hereinafter referred to as EMMA-2)

MFR (190°C, 21.18 N, method A) 2 g/10 min

Content of the monomer unit derived from ethylene 80 mass %, content of the monomer unit derived from methyl methacrylate (MMA) 20 mass % (Let the mass of EMMA-2 be 100 mass %)

(Acrift (registered trademark) WH206-F manufactured by Sumitomo Chemical Co., Ltd.)

(3) Ethylene-methyl methacrylate copolymer (hereinafter referred to as EMMA-3)

MFR (190°C, 21.18 N, method A) 2 g/10 min

Content of the monomer unit derived from ethylene 90 mass %, content of the monomer unit derived from methyl methacrylate (MMA) 10 mass % (Let the mass of EMMA-3 be 100 mass %)

(Acrift (registered trademark) WD201-F manufactured by Sumitomo Chemical Co., Ltd.)

(4) Ethylene-methyl methacrylate copolymer (hereinafter referred to as EMMA-4)

MFR (190°C, 21.18 N, method B) 450 g/10 min

Content of the monomer unit derived from ethylene 68 mass %, content of the monomer unit derived from methyl methacrylate (MMA) 32 mass % (Let the mass of EMMA-4 be 100 mass %)

(Acrift (registered trademark) CM5022 Sumitomo Chemical Co., Ltd.)

(5) Ethylene-vinyl acetate copolymer (EVA) (hereinafter referred to as EVA-1)

MFR (190°C, 21.18 N, method A) 7 g/10 min

The content of the monomer unit derived from ethylene is 72 mass%, and the content of the monomer unit derived from vinyl acetate (VA) is 28 mass% (Let the mass of EVA-1 be 100 mass%)

(Smitate (registered trademark) KA-30 manufactured by Sumitomo Chemical Co., Ltd.)

(6) Ethylene-1-hexene copolymer (hereinafter referred to as ER-1)

MFR (190°C, 21.18 N, method A) 3.2 g/10 min

(Exelene (registered trademark) FX307 manufactured by Sumitomo Chemical Co., Ltd.)

Propylene-based polymers:

(1) Propylene-ethylene random copolymer (hereinafter referred to as rPP-1)

MFR (230 °C, 21.18 N, method A) 1.5 g/10 min

(Noverene (registered trademark) S131 manufactured by Sumitomo Chemical Co., Ltd.)

Polyolefin-based resin:

(1) Polyethylene resin (PE) (hereinafter referred to as PE-1)

MFR (190°C, 21.18 N, method A) 0.5 g/10 min

(Exelene (registered trademark) GMH GH030 manufactured by Sumitomo Chemical Co., Ltd.)

(2) Polyethylene resin (PE) (hereinafter referred to as PE-2)

MFR (190°C, 21.18 N, method A) 0.4 g/10 min

(Exelene (registered trademark) GMH GH051 manufactured by Sumitomo Chemical Co., Ltd.)

particle :

(1) OMicron (registered trademark) NP5-P0 (glass beads manufactured by Sovitec) (hereinafter referred to as particle-1)

Volume median diameter = 5 μm (laser diffraction method)

Refractive Index (23℃) = 1.51

(2) OMicron (registered trademark) NP3-P0 (glass beads manufactured by Sovitec) (hereinafter referred to as particle-2)

Volume median diameter = 3 μm (laser diffraction method)

Refractive Index (23℃) = 1.51

(3) Crosslinked methyl methacrylate-styrene copolymer particles (hereinafter referred to as particle-3)

Volume median diameter = 5 μm (Coulter counter method)

Refractive Index (23℃) = 1.51

(Tec Polymer (registered trademark) MSX-5Z manufactured by Sekisui Chemical Industry Co., Ltd.)

The films of Examples 1-4 and Comparative Example 1 provided with the layer of the resin composition were manufactured, and it evaluated.

[Example 1]

75 mass % of EMMA-1 and 25 mass % of particle-2 are mixed, used in a laboplasto mill (manufactured by Toyo Seiki Seisakusho Co., Ltd.), and kneaded for 5 minutes under conditions of a temperature of 150° C. and a rotational speed of 60 rpm, and the resin A composition was obtained. The said resin composition was press-molded at 150 degreeC, and the 100-micrometer-thick film was obtained by press-cooling at 10 degreeC after that. Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Example 2]

A resin composition and a film were obtained in the same manner as in Example 1 except that EMMA-2 was used instead of EMMA-1 and particle-1 was used instead of particle-2. Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Example 3]

45 mass % of EVA-1, 20 mass % of ER-1, 20 mass % of rPP-1, and 15 mass % of particle-3 were mixed, and the mixture was supplied to a laboplasto mill (manufactured by Toyo Seiki Seisakusho Co., Ltd.), temperature It knead|mixed for 5 minutes on the conditions of 150 degreeC and rotation speed of 60 rpm, and obtained the resin composition. The said resin composition was press-molded at 150 degreeC, and the 100-micrometer-thick film was obtained by press-cooling at 30 degreeC after that. Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Example 4]

<Master Batch>

A master batch composed of 50 parts by weight of EVA-1 and 50 parts by weight of particle-3 was used. This master batch was referred to as MB-1.

<Production of film>

A 3-layer inflation molding machine (Pla Co., Ltd.) comprising an inner layer extruder (40 mm extruder), an intermediate layer extruder (40 mm extruder), an outer layer extruder (40 mm extruder), and a 100 mmφ die (1.2 mm lip gap) Koh) was used to shape a three-layer tubular film.

Specifically, the material of the polyolefin-based resin composition for the outer layer is put into the extruder for the outer layer, the material of the resin composition for the intermediate layer of Example 4 is put into the extruder for the intermediate layer, and the material of the polyolefin-based resin composition for the inner layer is fed into the extruder for the inner layer. and after melt-kneading with each extruder, the discharge amount is adjusted so that the inner layer is 30 µm, the intermediate layer is 90 µm, and the outer layer is 30 µm (total thickness is 150 µm) from a 100 mm dia die, and each molten layer was extruded and cooled to obtain a three-layer tubular film. At this time, the extruder of the inner layer and the outer layer was set to 160 degreeC, and the extruder and the die|dies of the intermediate|middle layer were set to 150 degreeC.

In addition, the material of the polyolefin resin composition for outer layers was PE-1 and PE-2, and, as for the compounding quantity, PE-1 was 50 mass %, and PE-2 was 50 mass %. Moreover, the material of the resin composition for intermediate|middle layer of Example 4 is EVA-1, ER-1, rPP-1, and MB-1, and, as for the compounding quantity, EVA-1 is 30 mass %, and ER-1 is 20 mass. %, rPP-1 was 20 mass%, and MB-1 was 30 mass%. The material of the polyolefin-based resin composition for the inner layer was the same as that of the polyolefin-based resin composition for the outer layer.

Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Example 5]

<Production of film>

The material of the polyolefin resin composition for outer layer was PE-1 and PE-2, and, as for the compounding quantity, PE-1 was 50 mass % and PE-2 was 50 mass %. Moreover, the material of the resin composition for intermediate|middle layer of Example 5 is EVA-1, ER-1, rPP-1, and MB-1, and, as for the compounding quantity, EVA-1 is 10 mass %, and ER-1 is 40 mass. %, rPP-1 was 20 mass%, and MB-1 was 30 mass%. The material of the polyolefin-based resin composition for the inner layer was the same as that of the polyolefin-based resin composition for the outer layer. Other than that, it carried out similarly to Example 4, and obtained the multilayer film of 3 layers.

Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Comparative Example 1]

A resin composition and a film were obtained in the same manner as in Example 2 except that EMMA-3 was used instead of EMMA-2. Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Comparative Example 2]

50 mass % of EMMA-1, 25 mass % of EMMA-4, and 25 mass % of particle-1 are mixed, and it uses to the laboplasto mill (made by Toyo Seiki Seisakusho Co., Ltd.), temperature 100 degreeC, and rotation speed 60 rpm It kneaded for 5 minutes under conditions, and obtained the resin composition. The said resin composition was press-molded at 100 degreeC, and the 100-micrometer-thick film was obtained by press-cooling at 10 degreeC after that. Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Comparative Example 3]

<Master Batch>

49.2 parts by mass of EMMA-2, 50 parts by mass of particle-1, and 0.8 parts by mass of Irganox (registered trademark) 1010 (manufactured by BASF) as an antioxidant were supplied to an intensive mixer (manufactured by Nippon Roll Co., Ltd.), and 5 at 160°C The masterbatch for the resin composition for intermediate|middle layers was obtained by supplying and extruding and pelletizing the mixture obtained by minute mixing to a 65 mm (phi) single screw extruder (made by Nippon Steel Works). This master batch was referred to as MB-2.

<Production of film>

A 3-layer inflation molding machine (Pla Co., Ltd.) comprising an inner layer extruder (40 mm extruder), an intermediate layer extruder (40 mm extruder), an outer layer extruder (40 mm extruder), and a 100 mmφ die (1.2 mm lip gap) Koh) was used to shape a three-layer tubular film.

Specifically, the material of the polyolefin-based resin composition for the outer layer is put into the extruder for the outer layer, the material of the resin composition for the intermediate layer of Comparative Example 3 is put into the extruder for the intermediate layer, and the material of the polyolefin-based resin composition for the inner layer is fed into the extruder for the inner layer. and melt-kneaded with each extruder, then from a 100 mm dia die, the discharge amount is adjusted so that the inner layer becomes 50 µm, the intermediate layer becomes 50 µm, and the outer layer becomes 50 µm (total thickness is 150 µm), and each molten layer was extruded and cooled to obtain a three-layer tubular film. At this time, the extruder of the inner layer and the outer layer was set to 160 degreeC, and the extruder and the die|dies of the intermediate|middle layer were set to 150 degreeC.

In addition, the material of the polyolefin resin composition for outer layers was PE-1 and PE-2, and, as for the compounding quantity, PE-1 was 50 mass %, and PE-2 was 50 mass %. Moreover, the material of the resin composition for intermediate layers of Comparative Example 3 was EMMA-2 and MB-2, and, as for the compounding quantity, EMMA-2 was 50 mass %, and MB-2 was 50 mass %. The material of the polyolefin-based resin composition for the inner layer was the same as that of the polyolefin-based resin composition for the outer layer.

Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

[Comparative Example 4]

<Production of film>

The material of the polyolefin resin composition for outer layer was PE-1 and PE-2, and, as for the compounding quantity, PE-1 was 50 mass % and PE-2 was 50 mass %. Moreover, the material of the resin composition for intermediate layers of Comparative Example 4 was EMMA-1 and MB-2, and, as for the compounding quantity, EMMA-1 was 50 mass % and MB-2 was 50 mass %. The material of the polyolefin-based resin composition for the inner layer was the same as that of the polyolefin-based resin composition for the outer layer. Other than that, it carried out similarly to the comparative example 3, and obtained the 3-layer multilayer film.

Table 2 shows the coefficient of linear expansion of the obtained film, the ratio of the dispersed phase with an equivalent circle diameter of 1 µm to 10 µm, the haze value at 0°C and 40°C, and the value of 1% SM at 23°C.

Moreover, as for the agricultural film, if the linear expansion coefficient is 1.5 x 10 ^-4 K ^-1 or more and 2.8 x 10 ^-4 K ^-1 or less, the change in haze value in the temperature range of 0 ° C. to 40 ° C., that is, more than 25 ° C. It was confirmed that the change in haze value extended to a high temperature range was large. Moreover, it was confirmed that the value of 1% SM in 23 degreeC was also high that a coefficient of linear expansion was 2.8 x 10 ^-4 K ^{-1 or less.}

Industrial Applicability

The film according to the present invention can be suitably used as a covering material or the like in a greenhouse for plant cultivation or an agricultural and horticultural facility such as a tunnel.

Claims (5)

A film which has at least one layer which consists of a continuous phase and a dispersed phase, and satisfy|fills following (A) and (B);
(A) In the cross section cut in the direction perpendicular to the film surface and parallel to the slow axis in the film plane, the ratio of the area of the cross section of the dispersed phase with the equivalent circle diameter of 1 µm to 10 µm among the dispersed phases is 1% or more and 30% or less with respect to the area of the cross-section of the layer;
(B) the coefficient of linear expansion calculated by the following formula (1) is 1.5 × 10 ^-4 K ^-1 or more and 2.8 × 10 ^-4 K ^-1 or less,
Coefficient of linear expansion = (L _{25 ℃} - L _{0 ℃} )/(25 ℃ - 0 ℃) (1)
Here, L _25° C represents the length of the film in the direction perpendicular to the film surface at 25°C, and L _0°C represents the length of the film in the direction perpendicular to the film surface at 0°C. The method of claim 1,
The continuous phase is a film comprising a thermoplastic resin. 3. The method of claim 2,
The thermoplastic resin film is a polyolefin-based resin. 4. The method according to any one of claims 1 to 3,
The refractive index of the component included in the dispersed phase is 1.50 or more and 1.53 or less. The agricultural and horticultural facility in which the film in any one of Claims 1-4 was fully mounted in the agricultural/horticultural facility frame.