JPH05153869A - Agricultural vinyl chloride-based resin film - Google Patents

Abstract

PURPOSE:To obtain the subject film capable of changing an amount of light introduced into a greenhouse between summer and winter seasons by adding a specific fluorescent agent to a vinyl chloride-based resin to form a film and providing one side of the film with straight channels so as to satisfy a specific condition. CONSTITUTION:One side or both sides of a film comprising 0.01-5 pts.wt. based on 100 pts.wt. vinyl chloride-based resin of a fluorescent agent (preferably oxazole type fluorescent agent) to excite ultraviolet rays are provided with straight channels in such a way that the channels are mutually parallel, angles A and B of two opposing inclined planes of a triangle formed by sections of the channels from the film surface satisfy formula I to formula IV, depth of the channels is 1/50-3/10 thickness of the channels, pitch of the channels is 5-200mum and the whole area of zone of the channel part is >=30% the area of the film surface to give the objective film.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an agricultural vinyl chloride resin film. More specifically, the present invention relates to an agricultural vinyl chloride resin film having a function of controlling the amount of light rays that are incident on a house and are effective for plant growth.

[0002]

2. Description of the Related Art Conventionally, so-called institutional horticulture, in which useful plants are forcibly cultivated in a house or a tunnel, has been widely used and utilized for stable supply of fresh vegetables, fruits, flowers and the like. A vinyl chloride resin film is often used as a material for covering a house or a tunnel for performing such horticulture because of its excellent weather resistance, transparency, heat retention and strength.

However, in the summer, the temperature in the house or the tunnel rises, and the temperature rises above the optimum temperature for plant cultivation. Therefore, usually, a part of the house or the tunnel is opened and ventilated, and a light-shielding net or a frosted cloth is used to prevent the temperature from rising. Such work related to temperature control is performed from before summer to summer, which is very time-consuming.

On the other hand, in winter, the temperature and light rays required for plant growth are often insufficient due to weak light rays, and temperature and light ray replenishment are required to further enhance the forcible cultivation effect. Therefore, it is desired that the inside of the house or the tunnel is dimmed in the summer and brightened in the winter. As a method of adjusting the amount of incident light into the house or the tunnel, it is known to use the principle of a prism to reduce the light in the house in the summer and to increase the light in the winter. In this, for example, one side of a sheet made of a hard resin such as acrylic resin is processed into a sawtooth-shaped cross section so that each of the irregularities serves as a prism. However, hard materials such as acrylic are expensive, and the form of the house is limited to the roof type house. Further, a soft vinyl chloride resin film provided with irregularities of prismatic stripes is also known (for example, Japanese Patent Laid-Open No. 62-22520). There was no.

On the other hand, as a method of efficiently using light,
In order to convert the ultraviolet rays of 380 nm or less, which are not used for plant growth by sunlight, into useful light rays, there is a method of using a fluorescent agent that is excited by ultraviolet rays and converted into light rays on the long wavelength side. When compounded, only a part of the light emitted after the light quality conversion was incident on the house, and the effective use of the light quality conversion was not sufficient.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a vinyl chloride resin film for agriculture, which has a function of reducing the amount of light rays incident on the inside of a house, which are effective for plant growth, in the summer and increasing the light in the winter. The purpose is that.

[0007]

The present inventors have found that the agricultural vinyl chloride resin film intended by the present invention can be obtained by incorporating a fluorescent agent into a film substrate having grooves of a specific shape. Found and completed the present invention. That is,
The gist of the present invention is to provide linear grooves on one surface or both surfaces of a film, and the angles A and B formed by two inclined surfaces which are parallel to each other and which are opposed to each other and which form a triangular cross-section with the film surface are as follows. The relational expression is satisfied, the groove depth is 1/50 to 3/10 of the film thickness, and the groove pitch is 5 to 200 μ.
m or less, and the total area of the groove region occupies 30% or more of the area of the film surface.
0.01 parts by weight of a fluorescent agent excited by ultraviolet rays is used per 0 part by weight.
A vinyl chloride resin film containing 5 to 5 parts by weight.

A ≤ B ≤ 1.5A A + B ≤ 110 ° 10 ° ≤ A ≤ 60 ° 10 ° ≤ B ≤ 90 ° Here, the angles A and B formed by the inclined surface of the groove and the film surface are:
It means the corners A and B in FIG. Hereinafter, the present invention will be described in detail.

In the present invention, the vinyl chloride resin means polyvinyl chloride, a copolymer of vinyl chloride as a main component with other comonomer, or a mixture with these copolymers. The agricultural vinyl chloride resin film of the present invention contains 20 to 60 parts by weight of a commonly used plasticizer per 100 parts by weight of the vinyl chloride resin in order to impart flexibility.

Examples of the fluorescent agent excited by ultraviolet rays used in the present invention include stilbene type fluorescent agents such as diaminostilbene disulfonic acid derivatives; benzidine derivatives,
Diaminodiphenyl type fluorescent agents such as benzidine sulfonic acid derivatives and diaminofluorene type derivatives; imidazole type fluorescent agents; imidazolone type fluorescent agents; triazole type fluorescent agents; thiazole type fluorescent agents; oxazole type fluorescent agents; coumarin type fluorescent agents; carbostyril. -Type fluorescent agents; naphthalimide-type fluorescent agents; pyrazoline-type fluorescent agents and dihydropyridine-type fluorescent agents, as well as organic fluorescent agents currently on the market, yttrium vanadate-activated europium (YVO ₄ : Eu); strontium phosphate · Magnesium tin activator [(SrMg) ₃ (PO ₄ ) ₂ : S
n], a manganese activator of magnesium fluorogermanate (3.5MgO · 0.5MgF ₂ · GeO ₂ : M
Inorganic fluorescent agents such as n) are particularly preferable, and oxazole type fluorescent agents are particularly preferable. Specifically, for example, the following general formulas (I) to
Examples thereof include compounds represented by formula (III), and particularly, compounds represented by general formula (I)
Compounds represented by are preferred.

[0011]

[Chemical 1]

(In the formula, R ₁ and R ₂ are hydrogen and have 1 to 4 carbon atoms.
Represents an alkyl group or an alkoxy group having 1 to 4 carbon atoms,
R ₃ and R ₄ represent hydrogen or an alkyl group having 1 to 4 carbon atoms,
X and Y represent an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an amino group substituted with an alkyl group having 1 to 4 carbon atoms, an anilino group, or an aryl group. ) The ratio of the fluorescent agent to be mixed with the vinyl chloride resin is generally 100 parts by weight of the vinyl chloride resin to be mixed,
It is 0.01 to 5 parts by weight. If the addition amount is less than 0.01 parts by weight, the fluorescence is weak and the effect of brightening in winter is insufficient, and if it exceeds 10 parts by weight, on the contrary, the self-quenching action occurs and the fluorescence is not exhibited, which is not preferable.

If desired, the agricultural film of the present invention may contain known additives which are usually incorporated in a synthetic resin for molding. These additives are added in a usual amount, for example, 100 parts by weight of vinyl chloride resin,
It can be used in an amount of 10 parts by weight or less. In order to add the above-mentioned compound to the vinyl chloride resin, a usual compounding or mixing technique may be adopted. Specifically, for example, a method using a ribbon blender, a Banbury mixer, a super mixer, or another compounding machine or mixer can be adopted.

In order to produce a film from the composition of the soft vinyl chloride resin thus obtained, a commonly used film production method such as calender molding method, extrusion molding method, inflation molding method, etc. is appropriately used. Can be adopted. In the present invention, in order to form the groove on the surface of the coating material, even if directly processed by laser irradiation,
It is also possible to use ion beam etching, photoetching (combination of photoresist and etching), photoelectroforming (combination of photoresist and electroforming), or a method of embossing after forming an uneven metal mold by cutting or the like.

The shape of the groove can be variously changed by adjusting the shape of the embossing roll and the temperature of the film at the inlet of the sumbossing roll. One of the angles A and B formed by the slope of the groove and the film surface is smaller than a predetermined angle, that is,
When the angles A and B are less than 10 °, the dimming effect in summer and the brightening effect in winter do not occur.

Further, in order to enhance the effect of adjusting the amount of incident light, the angle A and the angle B may be increased, but if the groove width is large, the groove depth also becomes large, so that the physical properties of the film such as impact strength deteriorate. Therefore, the sum of the angle A and the angle B needs to be 110 ° or less. When A ≦ B ≦ 1.5A and no fluorescent agent is added, the effect of brightening in winter is insufficient,
Addition of a fluorescent agent for converting the quality of ultraviolet light fully exerts the brightening effect in winter.

If the groove pitch is less than 5 μm, the inclination angle of the film is not clear and the amount of light is not adjusted, and if the groove depth is less than 1/50 of the film thickness or the groove area If the total area is less than 30% of the area of the film surface, the refraction of light becomes small, and the amount of light incident on the house cannot be adjusted sufficiently. Therefore,
The film groove depth (D in FIG. 1) is 1/50 to 3/10 of the film thickness (T in FIG. 1), the groove bitches (p in FIG. 1) is 5 to 200 μm, and the total groove area The area is 30% or more of the surface area of the film.

Further, the agricultural vinyl chloride resin film according to the present invention is preferably improved in addition to the dustproof property on the outside of the film. In order to improve the dustproof property, it is preferable to form a dustproof film based on a solvent paint, a water-soluble paint or an ultraviolet curable paint.

[0019]

EXAMPLES The present invention will be described in detail below based on examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. I. Production of film (reference example) Polyvinyl chloride (average degree of polymerization = 1300) 100 parts by weight Dioctyl phthalate 45 〃 Tricresyl phthalate 5 〃 Epoxy resin plasticizer 1 〃 Ba-Zn liquid stabilizer 1 〃 Ba-Zn Powder stabilizer 1 〃 barium stearate 0.2 〃 zinc stearate 0.4 〃 sorbitan monostearate 2.0 〃 benzophenone-based UV absorber 0.1 〃 with the basic composition and the fluorescent agent shown in Table 1 Blended and mixed with a super mixer. This mixture was supplied to a calendar roll heated to 180 ° C. to form a film having a thickness of 0.1 mm.

II. Groove formation Photo-etching (when grain pitch is 20 and 50) or cutting (grain pitch is 100, 150)
And 250), the embossing roll having a diameter of 210 mm and the surface shape shown in FIG. 2 and the grain pitch and grain depth shown in Table 1 are used.
The film produced in the above-mentioned I heated to 10 ° C. was passed between water-cooled embossing rolls so as to have a pressure of 0.5 kg / cm, thereby forming a groove on one surface.

The surface shape of the obtained film was measured by a three-dimensional surface roughness meter (TOPO-3D) manufactured by Matsu Trading Machine Co., Ltd., and the area ratio of the groove area was calculated by the power spectrum.

III. Evaluation of Film The film of the present invention having the groove formed in II on the roof portion of the gable type model house shown in FIG. I made something that was stretched so that it was parallel to the direction. As a control, a house having the same shape was formed by spreading the film having no groove formed in I. On the inner floor surface of each house, three photon sensors (manufactured by Koito Industry Co., Ltd. IKS-25) were installed at intervals of 1 m in the direction perpendicular to the ridge. Each house was arranged so that the ridges face east-west.

The measurement was carried out on a sunny day in September 1991 at a farm in Aichi Prefecture. In that case, assuming the winter solstice and the summer solstice, the incident angle of the sunlight to the house at the time of south-central time was the winter solstice and the summer solstice. The house was tilted north-south so that it was at the same angle as the sun.
The measurement data is displayed as a relative value when the amount of light incident on the control house is 100 at the time of the south central time.

The impact strength of the obtained film was measured with a puncture manufactured by Toyo Seiki Co., Ltd. Table 1 shows each measurement result.

[0025]

[Table 1]

[0026]

INDUSTRIAL APPLICABILITY The agricultural film of the present invention has the effect of reducing the amount of light incident on a house in summer and increasing it in winter.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example of the film of the present invention, where T is the film thickness, A and B are the angles between the inclined surface of the groove and the film surface, p is the groove pitch, and D is the groove. Depth is shown respectively.

FIG. 2 is an embossed throw used in Examples and Comparative Examples.
Is a schematic cross-sectional view of the surface of ₁And θ₂Is tilted
Corners, p represents pitch, and D represents emboss depth.

FIG. 3 is a schematic diagram of a model house used for evaluation of a film in the examples, where 1 is a house, 2 is the sun at the time of south central time, and 3, 3'and 3 '' are photon sensors. To 4,4 '
Is a test film stretched on the roof, 5 and 5'are house walls, 6 is a light irradiation angle setting device, and 7 is the ground.

Claims (1)

[Claims] 1. Angles A and B formed by linear grooves on one side or both sides of a film, which are parallel to each other, and each of two opposing inclined surfaces of a triangle formed by the groove cross section form a film surface. Satisfying the formula, A ≤ B ≤ 1.5A A + B ≤ 110 ° 10 ° ≤ A ≤ 60 ° 10 ° ≤ B ≤ 90 °, and the groove depth is 1/50 to 3/10 of the film thickness. The groove pitch is 5 to 200 μm, the total area of the groove area accounts for 30% or more of the area of the film surface, and 0.01 to 100 parts by weight of the vinyl chloride-based resin contains 0.01 to 100 μm of a fluorescent agent excited by ultraviolet rays. A vinyl chloride resin film for agriculture containing 5 parts by weight.