KR101553562B1 - film for farmer's hut - Google Patents

Abstract

The present invention relates to a film for building an agricultural tent. The film includes an outer layer and a middle layer. The film can additionally include an inner layer. The outer later includes: 28-56 parts by weight of an ethylene vinyl acetate (EVA) copolymer; 28-58 parts by weight of metallocene polyethylene (mPE); 5-15 parts by weight of aluminum; and 9-20 parts by weight of a sunscreen agent. The middle layer formed on the lower side of the outer layer includes: 25-52 parts by weight of the EVA copolymer, 25-52 parts by weight of metallocene liner low-density polyethylene (mLLDPE); 5-15 parts by weight of aluminum; 8-20 parts by weight of a sunscreen agent; 5-10 parts by weight of a ceramic material; 5-10 parts by weight of a heat insulation agent. The inner layer formed on the lower part of the middle layer includes: 25-51 parts by weight of the EVA copolymer, 25-51 parts by weight of low density polyethylene (LDPE); 8-20 parts by weight of a sunscreen agent; 10-15 parts by weight of pigments; and 6-14 parts by weight of a water-repellent agent. The outer and middle layer has evenly distributed amounts of aluminum to roughly block 97% of sunlight excellently by using the aluminum and heat insulation agent. The film also prevents the heat on the ground from traveling upwardly and reflects the heat to the lower side to insulate the heat of the ground. The film blocks the outside temperature from being transferred to the space in the agricultural tent to cool the temperature in the agricultural tent. The snow coming in contact with the film quickly melts to slip off from the agricultural tank and be easily removed.

Description

Film for farmer's hut

More particularly, the present invention relates to a film for agricultural film, and more particularly, to a film for agricultural use, which comprises an ethylene vinyl acetate copolymer (EVA), a metallocene polyethylene (mPE), a metallocene linear low density polyethylene (mLLDPE) and a low density polyethylene , A sunscreen, a ceramic and a thermosetting agent to produce a film for agricultural use which is excellent in light shielding property, heat insulation property and weather resistance and is easy to produce.

The sunlight can be divided into infrared rays, ultraviolet rays and visible rays. Infrared rays are electromagnetic waves that are farther from the end of the red line when dispersing the light emitted from the sun by the prism. The infrared rays have a wavelength of 0.78 ~ 3 nm is called near infrared, 3 to 25 nm is infrared, 25 nm or more is far infrared ray, infrared is stronger than visible light or ultraviolet ray, and it is called heat ray.

Ultraviolet rays are short wavelengths of visible light and are invisible light. It is a collective term of electromagnetic wave with wavelength of about 10 ~ 380nm. It is called chemical ray because it has strong chemical action.

Visible light means light having a wavelength range perceived by the eye, and is an electromagnetic wave having a wavelength in the range of about 380 to 780 nm, which is useful for photosynthesis required by a plant. Particularly, light of 400 to 700 nm is converted into photosynthetic active light (PAR: Photosynthetically Active Radiation).

On the other hand, light in the wavelength range of 100 to 400 nm reduces the leaf area of plants, decreases the rate of photosynthesis, adversely affects most plant species, such as influencing the flowering time and number of days of flowering, Increases the temperature of fruits and leaves, and increases the temperature in the greenhouse.

Agricultural shading covers are used in agricultural facilities, such as vinyl houses for greenhouse cultivation, glass greenhouses, and other facilities such as farmhouses that control certain growth conditions or block or mitigate the effects of external environments, including housing for livestock breeding .

The agricultural light-shielding cover means a cover or screen which is applied or adhered to a facility such as vinyl, glass, or the like capable of transmitting light, for example, to provide a light-shielding effect to a window or glass door of a farming culture.

[0005] In view of the prior art agricultural light-shielding cover,

Korean Patent Publication No. 10-0735153 An agricultural light-shielding screen in an agricultural light-shielding screen and a method of manufacturing the same (July 03, 2007) comprises an aluminum foil having a thickness of 6 to 8 μm; A polyethylene terephthalate (PET) film having a thickness of 23 to 27 占 퐉 formed by pressing on both surfaces of an aluminum foil through a urethane resin having a thickness of 6 to 8 占 퐉; A light-shielding sheet is formed with an ultraviolet shielding film having a thickness of 2 to 5 占 퐉 formed by coating on the surface of a polyethylene terephthalate film, cutting the light-shielding sheet into strips, and then woven into a polyester thread.

The light shielding screen for agricultural use is produced by cutting the light shielding sheet into a strip shape and then weaving it into a polyester yarn in a zigzag manner. The light shielding sheet is cut and woven to reduce the productivity. The urethane resin reduces the flexibility of the product. Discoloration, brittleness, cracking, and the like.

A shading cover for agricultural use (May 27, 2002) is composed of a PE coated paper woven fabric formed on the upper side, a PE woven fabric formed on the lower side of the PE coated woven fabric, And a folding chamber formed by penetrating from the uppermost part to the lower part so that the laminated woven fabrics are laminated with a PE weaving fabric formed at the lower part of the waterproof paper and then integrated with a sewing machine.

The shade for agricultural use is made by cutting paper woven fabric, PE woven fabric into strips, cutting the paper woven fabric, PE woven fabric, and waterproofing paper and laminating them. The paper woven fabric and the PE woven fabric are cut and stitched in strips The surface is not smooth due to the poor productivity, the surface is not smooth, the sunlight is not reflected, the snow is piled up when the snow falls, and the life of the product is short due to the paper weft.

(EVA) and metallocene polyethylene (mPE) in the outer layer and an ethylene vinyl acetate copolymer (EVA) and a metallocene linear copolymer (EVA) in the middle layer. The present invention has been accomplished in order to solve the above- It is possible to mix the aluminum film, the ultraviolet screening agent, the ceramic or the warming agent while specifying the low density polyethylene (mLLDPE), and the one at the same time by mixing the water repellent with the blown film while specifying the ethylene vinyl acetate copolymer (EVA) and low density polyethylene (LDPE) And to provide a film for agricultural film which is easy to produce without interruption of external temperature and water droplet formation in the geothermal heat during the winter season and during the winter season.

The present invention relates to a film for film for agricultural film, which comprises 28 to 58 parts by weight of an ethylene vinyl acetate copolymer (EVA), 28 to 58 parts by weight of metallocene polyethylene (mPE), 5 to 15 parts by weight of aluminum, 9 to 20 parts by weight of a blocking agent; 25 to 52 parts by weight of an ethylene vinyl acetate copolymer (EVA), 25 to 52 parts by weight of a metallocene linear low density polyethylene (mLLDPE), 5 to 15 parts by weight of aluminum, 8 to 20 parts by weight of an ultraviolet blocking agent, To 10 parts by weight, and a warming agent of 5 to 10 parts by weight.

The present invention also relates to a method for producing a water-repellent film, comprising the steps of: 25 to 51 parts by weight of ethylene vinyl acetate copolymer (EVA); 25 to 51 parts by weight of low density polyethylene (LDPE); 8 to 20 parts by weight of an ultraviolet screening agent; 6 to 14 parts by weight of an inner layer.

In the present invention, the aluminum is a powder having a particle size of 300 to 400 mesh.

In addition, the present invention is characterized in that the ultraviolet screening agent is selected from the group consisting of titanium dioxide, zinc oxide, zirconium oxide, glyceryl PABA, Drometrizole, (3-methylbenzylidene) Camphor, Menthyl anthranilate, Benzophenone-3, Benzophenone-4, Benzophenone-4, benzophenone-8, butyl methoxydibenzoylmethane, cinoxate, octocrylene, octyldimethyl PABA, octylmethoxy Octyl methacrylate, octyl methoxy cinnamate, octyl salicylate, octyl triazone, para-aminobenzoic acid, 2-phenylbenzimidazole -5-sulfonic acid, homosalate, drometrizole trisiloxane (Drometrizole Trisiloxane, disodium phenyl dibenzimidazole tetrasulfonate, bis-ethylhexyloxyphenol methoxyphenyl triazine, isoamyl-p-methoxy cinnamate (Isoamyl p-Methoxycinnamate, Oxybenzone Zinc Oxide, Avobenzone, Dioxybenzone, Sulisobenzone, Mexoryl SX, Aminobenzoic acid, , PABA), trolamine salicylate, and Padimate-0 (Padimate-0).

The present invention also relates to a method for producing a ceramic material, wherein the ceramic is selected from the group consisting of alumina, silicon oxide, magnesium oxide, sodium oxide, calcium oxide, titanium dioxide, zirconia ), Silicon carbide. Silicon nitride, barium titanate, and the like.

Also, the present invention is characterized in that the warming agent is a sbestos heat insulating material, a istomaceous earth heat insulating material, a rock wool heat insulating material, a calcium silicate heat insulating material, A magnesium carbonate heat insulating material, a glass wool heat insulating material, and a blast furnace slag heat insulating material.

The present invention also relates to the use of the pigment as a coloring agent in an aluminum pigment, a bronze pigment and a ferric pigment, Carbon black, Cobalt green, Cobalt blue, Yellow ocher, It is also possible to use oxides such as Oxidize red iron, Viridian, Cadmium yellow, Ultra marine blue, TiO2, Iron oxide green and Hansa yellow. Lt; / RTI >

In the present invention, the water repellent agent is any one selected from the group consisting of aluminum, silane, silicone and urethane.

The film for agricultural film of the present invention has an effect that sunlight is shielded from sunlight by secondary light shielding and reflection of primary and middle aluminum layers of the outer layer aluminum because the amount of aluminum is uniform in the outer layer and middle layer.

Further, according to the present invention, when installed for light shielding of the agricultural film, the outside air due to the aluminum in the outer layer and the middle layer is cut off, the geothermal heat is prevented from being moved to the outside by the heat preservative and ceramics in the middle layer, It is effective to prevent the external temperature from being transferred to the inner part of the farmland in the summer, and to cool the temperature inside the farmland.

In addition, the present invention is resistant to heat by nonflammable aluminum, ceramics, and warming agents, and is less damaged by an external impact, has a high strength, and is less prone to wrinkles.

In addition, according to the present invention, even when snow falls in the winter season by reflecting the sunlight, the snow contacting with the film for agricultural film melts quickly and slips on itself, and the snow can be easily removed.

In addition, the present invention has an effect that the damage of the agricultural film is small due to easy slip of the snow or easy removal of snow.

Further, the present invention has an effect of being excellent in flexibility and elasticity at room temperature as compared with a film composed only of polyethylene type by ethylene vinyl acetate copolymer (EVA) and having a smooth surface.

Further, the present invention has the effect that water drops are not formed on the inner surface of the film by the water repellent agent in the film.

In addition, the present invention has an effect that ultraviolet rays are blocked by an ultraviolet screening agent in a film, thereby preventing exposure of the worker in the film to ultraviolet rays and preventing oxidation of the film, thereby improving weatherability.

In addition, since the present invention is produced at one time by the production of a film as a blown film and there is no need to sew the film, the production cost is low.

1 is a cross-sectional view of a triple blown film for a film for agricultural use in accordance with the present invention.
2 is a cross-sectional view of a triple-layer film of the present invention.
3: photograph of the outer layer of the film for the present invention.
4: inner layer photograph of the film for the present invention.

Hereinafter, preferred embodiments of the film for agricultural use of the present invention will be described with reference to the accompanying drawings.

The synthetic resin to be used in the present invention is preferably a thermoplastic resin selected from the group consisting of ethylene vinyl acetate copolymer (EVA), metallocene polyethylene (mPE), metallocene linear low density polyethylene (MLLDPE), metallocene-catalyzed linear low density Polyethylene, and low density polyethylene (LDPE).

In general, a synthetic resin film is produced by supplying a synthetic resin chip, which is a raw material of a melting resin, to a hopper of an extruder, melting a synthetic resin chip at 160 to 220 ° C by a heater, extruding the melted resin with a cylinder and an extruding screw, The tube-shaped film that has been expanded by the blowing air of the air ring by the blown film forming apparatus is cooled by the air blown by the blowing air of the air-ring film forming apparatus and is raised into a cylindrical shape to become a cylindrical film, The film is passed between a pair of rollers so that both sides are folded and folded into a two-fold film. One folded side of the two-fold film is cut with a cutting knife and wound around a finally wound winding reel.

At this time, the same number of extruders corresponding to the number of layers of the synthetic resin film is constituted, and the synthetic resin chips of the film layer are supplied for each hopper, and the synthetic resin is melted for each extruder, and each of the melted resins is laminated in a blown film molding machine, The film is cooled by the blowing air of the air ring, folded by the roller, folded by the cutter knife is cut and wound on the take-up reel to form a multi-layer roll film.

Ethylene Vinyl Acetate Copolymer (EVA) preferably has a low vinyl acetate content of 10 wt% or less and is preferably processed at a temperature of 200 ° C or lower. Ethylene and vinyl acetate are copolymerized (hybridized) under high pressure It is obtained by drying and neutralization of excess alkali, and is excellent in gas barrier property, gas barrier property, chemical resistance, surface gloss and rigidity.

The ethylene vinyl acetate copolymer (EVA) is a kind of polyolefin thermoplastic resin produced from a high-pressure polyethylene polymerization apparatus and can be extruded. The EVA is superior in flexibility at room temperature to other types of polyethylene resins, And it can be extruded as thermoplastic. It is used for heavy-wall materials, adhesives for laminate films, etc., and is widely used for agricultural film, food packaging, multilayer film, jelly cup, ketchup bottle, juice box, shrink film, etc. .

Generally, polyethylene (PE) separates crude oil of petroleum and separates naphtha part (100 ~ 200 ℃ effluent part) and decomposes it to produce about 25% of ethylene (Ethylene) In some cases, side chains (side chains: side chains) are formed. The smaller the side chains, the higher the density and the higher the density because of the higher density.

The density of the polyethylene (PE) varies depending on the polymerization method. Depending on the density of the plastic, it may be classified into low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE) , Cross Linking Polyethylene (XLPE), and metallocene Polyethylene (mPE).

The low density polyethylene (LDPE) may be selected from very low density polyethylene (VLDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE) and metallocene linear low density polyethylene (mLLDPE: Metallocene-catalyzed Linear Low Density Polyethylene).

The polymerization of linear low density polyethylene (LLDPE) and high density polyethylene (HDPE) is also called low pressure polyethylene because polymerization is carried out at a lower pressure using a catalyst, whereas low density polyethylene (LDPE) (LDPE), it is also called rigid polyethylene.

The low density polyethylene (LDPE) is tough due to its low melting point (Tm: Melting point) of 105 to 115 ° C, but has excellent processability, flexibility and transparency because the tensile strength is not strong, and the vicat softening point is 80 to 90 ° C. It does not maintain its physical properties at high temperature, it is supplemented with weak heat resistance through crosslinking method and is used as an agricultural film.

The metallocene polyethylene (mPE) is prepared by reacting an alpha -olefin, such as, for example, propylene, butene, hexene or octene, with an alpha-olefin in the presence of a single-site catalyst consisting of two cyclic alkyl molecules bonded to metal atoms of zirconium or titanium As polymers obtained by copolymerization of ethylene, metallocene catalysts usually consist of two cyclopentadiene rings bonded to a metal.

The metallocene linear low density polyethylene (mLLDPE) is an ethylene polymer which is polymerized in the presence of a metallocene catalyst, which is a metal converted into a cation sandwiched between cyclopentadiene anions, It is an ethylene copolymer with high tensile strength and easy to extrude. It is used for packaging and film production.

The present invention relates to an ethylene vinyl acetate copolymer (EVA), metallocene polyethylene (mPE), polyvinylidene fluoride (PVP), polyvinylidene fluoride (PVP) and the like, in order to shield ultraviolet rays while transmitting about 3% of sunlight using the characteristics of the synthetic resin and to improve heat insulation, weather resistance and durability of the film. , Metallocene linear low density polyethylene (mLLDPE) and low density polyethylene (LDPE) are specified and aluminum, ultraviolet screening agent, ceramic and warming agent are selected and mixed.

(PVA), metallocene linear low density polyethylene (mLLDPE) or low density polyethylene (LDPE) is mixed with the ethylene vinyl acetate copolymer (EVA) resin and aluminum, ultraviolet ray blocking agent, The light was shielded by about 97% to block the geothermal migration in the winter and to block the transfer of the summer 's external temperature to the inside of the paddy field, and it was specified as a film for agricultural film having flexibility and elasticity.

The ethylene vinyl acetate copolymer (EVA), the metallocene polyethylene (mPE), the aluminum and the ultraviolet screening agent are mixed in an appropriate amount and put into a hopper of a first extruder, melted and extruded to become a first molten resin.

The mixture of the ethylene vinyl acetate copolymer (EVA), metallocene linear low density polyethylene (mLLDPE), aluminum, ultraviolet screening agent, ceramic, and heat preserving agent in an appropriate amount is introduced into a hopper of a second extruder, melted and extruded, .

The ethylene vinyl acetate copolymer (EVA), the low density polyethylene (LDPE), the ultraviolet ray blocking agent, the pigment and the water repellent agent are mixed in an appropriate amount and put into a hopper of a third extruder, melted and extruded to become a third molten resin.

The first and second molten resins melted in the first and second extruders flow into the separated molten resin of the film forming apparatus and flow together to form a two-layer film, that is, .

At this time, the first molten resin becomes the outer layer 11 of the film for agricultural film 10, and the second molten resin becomes the film for double-grain film composed of the intermediate layer 12 of the film for agricultural use 10.

The first, second and third molten resins melted in the first, second and third extruders flow into the separated molten resin of the film forming apparatus, respectively, ) And discharged to the outside of the film forming apparatus.

At this time, the first molten resin serves as the outer layer 11 of the film for agricultural film 10, the second molten resin serves as the middle layer 12 of the film for agricultural film 10, (10) composed of the inner layer (13) of the film (10).

The outer layer 11 comprises an ethylene vinyl acetate copolymer (EVA) 28 ~ 58 parts by weight of a metallocene polyethylene (mPE) 28 ~ 58 parts by weight, aluminum 5 - 15 parts by weight, sunscreen 9-20 parts by weight .

When the ethylene vinyl acetate copolymer (EVA) of the outer layer 11 is 28 parts by weight or less, the flexibility of the film is good but the impact strength is decreased. When the amount of the ethylene vinyl acetate copolymer (EVA) is more than 58 parts by weight, the impact strength is good.

When the content of the metallocene polyethylene (mPE) in the outer layer 11 is 28 parts by weight or less, the flexibility of the film is good but the impact strength is decreased. When the content of the metallocene polyethylene is more than 58 parts by weight, the impact strength is good.

When the amount of aluminum in the outer layer 11 is 5 parts by weight or less, the transmittance of sunlight is large and the heat resistance is decreased. When the amount of aluminum is 15 parts by weight or more, the transmittance of sunlight is small, heat resistance is high and reflection (reflection) of radiant heat is good.

When the ultraviolet screening agent of the outer layer 11 is 9 parts by weight or less, the amount of ultraviolet rays transmitted is large and the oxidation of the film is prevented to improve the weatherability. When the amount of the ultraviolet screening agent is 20 parts by weight, the ultraviolet ray shielding is good and the weather resistance of the film is good. .

The intermediate layer 12 is further provided at the lower part of the outer layer 11 for the warmth of the film and the outer layer 11 and the intermediate layer 12 are formed by melting the synthetic resin for each extruder at the time of producing the synthetic resin film, In the blown film forming apparatus, the laminated resin, that is, the two layers of resin is discharged into a single cylindrical film, cooled by the blowing air of the air ring, folded by the rollers and folded by the cutting knife, Layer 11, and an intermediate layer 12 formed thereon.

The middle layer 12 is composed of 25 to 52 parts by weight of an ethylene vinyl acetate copolymer (EVA) 25 to 52 parts by weight of metallocene linear low density polyethylene (mLLDPE), 5 to 15 parts by weight of aluminum, 8 to 20 parts by weight of an ultraviolet screening agent, 5 to 10 parts by weight of ceramic, And 5 to 10 parts by weight of a warming agent.

The middle layer 12 When the ethylene vinyl acetate copolymer (EVA) is 25 parts by weight or less, the flexibility of the film is good but the impact strength is decreased. When the amount is more than 52 parts by weight, the impact strength is good but the flexibility is decreased.

When the metallocene linear low density polyethylene (mLLDPE) of the middle layer 12 is 25 parts by weight or less, the tensile strength of the film is low, and when it is more than 52 parts by weight, extrusion of the film becomes difficult.

When the aluminum of the intermediate layer 12 is less than 5 parts by weight, the transmittance of sunlight is large and the heat resistance is decreased. When the amount of aluminum is more than 15 parts by weight, the transmittance of sunlight is low, heat resistance is high and reflection of radiant heat is good.

When the amount of the ultraviolet screening agent in the middle layer 12 is less than 8 parts by weight, the amount of ultraviolet rays transmitted is increased to prevent oxidation of the film and improve the weatherability. When the amount of the ultraviolet screening agent is more than 20 parts by weight, do.

When the ceramics of the middle layer 12 is less than 5 parts by weight, the flexibility is good, but the emissivity of far infrared rays is decreased. When the amount is 10 parts by weight or more, adhesiveness and flexibility are lowered, but the surface of the film becomes rough, 13), and the film is resistant to heat by the ceramics and is light, but the damage due to external impact is small, the strength is large, and the occurrence of wrinkles is small.

When the warming agent of the intermediate layer 12 is 5 parts by weight or less, the effect of heat and cold is low. When the content of the middle layer 12 is 10 parts by weight or more, the effect of heat and cold is great, The surface becomes rough.

The inner layer 13 is further provided at the lower part of the middle layer 12 to prevent dew formation of the film and the outer layer 11 and the middle layer 12 and the inner layer 13 are made of synthetic resin for each extruder Each of the molten resins is discharged from the three-layered resin into a single cylindrical film in the blown film forming apparatus, cooled by the blowing air of the air ring, folded by the rollers, and folded by the cutting knife. That is, a roll film formed by winding three layers, that is, the outer layer 11, the middle layer 12 and the inner layer 13, on the take-up reel.

The inner layer 13 is composed of 25 to 51 parts by weight of ethylene vinyl acetate copolymer (EVA), 25 to 51 parts by weight of low density polyethylene (LDPE), 8 to 20 parts by weight of an ultraviolet blocking agent 10 to 15 parts by weight of a pigment, and 6 to 14 parts by weight of a water repellent agent.

When the ethylene vinyl acetate copolymer (EVA) in the inner layer 13 is 25 parts by weight or less, the flexibility of the film is good but the impact strength is decreased. When the content is more than 51 parts by weight, the impact strength is good but the flexibility is decreased.

Ethylene vinyl acetate copolymer (EVA) is used for the outer layer 11, the middle layer 12 and the inner layer 13 to have excellent flexibility at room temperature, excellent elasticity, and smooth surface compared to a polyethylene film.

When the low density polyethylene (LDPE) of the inner layer 13 is 25 parts by weight or less, the tensile strength of the film is low and when it is 51 parts by weight or more, extrusion of the film becomes difficult.

When the amount of the ultraviolet screening agent in the inner layer 13 is 8 parts by weight or less, the amount of ultraviolet rays transmitted is increased to prevent oxidation of the film and improve the weatherability. When the amount is 20 parts by weight or more, do.

When the pigment of the inner layer 13 is less than 10 parts by weight, there is a phenomenon in which the hue of color is not shown well, and when the amount of the pigment is more than 15 parts by weight,

When the water repellent agent of the inner layer 13 is 6 parts by weight or less, water repellency is insufficient. When the water repellent agent is 14 parts by weight or more, water droplets are not formed on the film but the inner layer 13 is not easily adhered to the middle layer 12 have.

Since the outer layer 11, the inner layer 13 and the middle layer 12 are laminated in a blown film forming apparatus at the time of production to form a single film, there is no need to separately laminate or sew the films at the site or after production, .

The composition and compositional ratio of the outer layer 11, the inner layer 13 and the intermediate layer 12 are slightly different from those of the ethylene vinyl acetate copolymer (EVA), aluminum, and the ultraviolet screening agent. Examples thereof include metallocene polyethylene (mPE) (LLDPE), low density polyethylene (LDPE), ceramics, heat preservatives, aluminum, water repellent and pigments.

The above aluminum is sprayed with compressed air while spraying a commonly known molten aluminum, and atomized aluminum particles and aluminum ingots made into fine particles are vigorously stirred while being kept in a semi-molten state in the air, A ball aluminum (Paint grade) and an aluminum foil which are made of powdered granular aluminum, Automized aluminum as a lubrication agent and a ball mill as a dispersing agent, And a stamp aluminum which is made to be powdered by hanging between the crushing rods.

When aluminum has a particle size of 300 mesh or less, the surface roughness of the outer layer 11 and the intermediate layer 12 becomes poor, and aluminum (Al) When the particle size is 400 mesh or more, workability is good, but the cost of processing is high because special precision milling is required.

In the case of the fine powder of aluminum, combustion starts at about 400 ° C., and when it comes into contact with water, acid, or alkali, there is danger of spontaneous ignition due to moisture or moisture. (EVA), metallocene polyethylene (mPE) or metallocene linear low density polyethylene (mLLDPE) by vacuum deposition before mixing and melting in the resin, Used to cover.

If aluminum is excessively contained in any one of the outer layer 11 and the middle layer 12, the amount of the synthetic resin of the ethylene vinyl acetate copolymer (EVA) and the metallocene polyethylene (mPE) of the outer layer 11 may become excessively small, (EVA) and the metallocene linear low density polyethylene (mLLDPE) of the ethylene / vinyl acetate copolymer (12) is excessively small, which makes it difficult to produce the film.

That is, when the amount of aluminum in the intermediate layer 12 is included in the outer layer 11, the amount of aluminum is at most 30 parts by weight in the intermediate layer 12, so that the surface of the middle layer 12 is passed over, The amount of aluminum of 10 to 30 parts by weight is uniformly dispersed in the outer layer 11 and the middle layer 12 in order to smooth the production of the film of the outer layer 11 and the middle layer 12, Thereby allowing the light to shade.

The solar light is firstly shielded by the aluminum of the outer layer and sunlight not primaryly shielded is shielded by outer layer and middle layer aluminum by about 97% of sunlight due to secondary light shielding .

When the film for agricultural film 10 is shaded with about 97% of the sunlight and transmitted by about 3% by the aluminum, the geothermal heat is prevented from moving to the outside of the upper part of the agricultural film in winter It is reflected to the inside of the farmland and the warmth of the geothermal heat is good. In summer, the outside temperature of the farmland is blocked from being transferred to the inside of the farmland, so that the inside of the farmland is cooled and the wrinkle of the film is small. Is small and the strength becomes large.

Even if the sun is reflected by the aluminum film (10) sunlight in the winter season, the snow contacting with the film for the sake film melts quickly and slips itself on the soda film or the snow easily.

In general, ultraviolet rays are divided into three regions according to wavelength, ultraviolet C (UV-C) at a wavelength of 200-290 nm, ultraviolet B (UV-B) at a wavelength of 290-320 nm, The wavelength is classified as ultraviolet A (UV-A).

Ultraviolet C (UV-C) passes through the ozone layer and disappears without reaching the surface of the earth. Ultraviolet B (UV-B) penetrates into the epidermis of the skin and is mostly absorbed in the epidermis, (UV-A) penetrates into the dermis of the skin causing damage to the skin, especially the skin that is constantly exposed to sensitive skin or sunlight Skin cancer, wrinkles, and melanin formation, leading to skin aging and skin irritation.

Among the above ultraviolet screening agents, the inorganic ultraviolet screening agent is also called a physical screening agent and protects ultraviolet rays from reacting to human skin by scattering light in the wavelength range of ultraviolet ray region. Organic ultraviolet ray blocking agent is also called chemical blocking agent and absorbs the wavelength range of ultraviolet ray region It protects UV rays from reacting to human skin, and depending on the kind of blocking agent, it can cause cloudiness due to high covering ability due to high refractive index of the material itself.

The ultraviolet screening agent may be an ethylene vinyl acetate copolymer (EVA), a metallocene polyethylene (mPE) or a polyvinylidene fluoride (PVP) by vacuum deposition before using the powder having an average particle size of 0.01 to 2 탆, Metallocene linear low density polyethylene (mLLDPE) and low density polyethylene (LDPE) are coated and used.

In the present invention, ultraviolet rays are blocked by an ultraviolet ray blocking agent in the film, and workers in the film are prevented from being exposed to ultraviolet rays, thereby protecting the skin caused by ultraviolet rays and blocking the disease, thereby being free from ultraviolet rays.

The ultraviolet screening agent may be selected from inorganic ultraviolet screening agents and organic ultraviolet screening agents which are generally known and include inorganic ultraviolet screening agents such as titanium dioxide, zinc oxide, zirconium oxide, and glyceryl PABA, , Drometrizole, Digalloyl Trioleate, 3- (4-Methylbenzylidene) Camphor, Menthyl anthranilate, Benzo Benzophenone-3, benzophenone-4, benzophenone-8, butyl methoxydibenzoylmethane, cinoxate, octocrylene, Octyl triazone, para-aminobenzoic acid, 2-ethylhexyl methacrylate, octyl methoxycinnamate, octyl salicylate, octyl triazone, Phenylbenzimidazole-5-sulfonic acid (2-Phe 5-sulfonic acid, homosalate, drometrizole trisiloxane, disodium phenyl dibenzimidazole tetrasulfonate, bishexylhexyloxyphenol methoxy But are not limited to, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Isoamyl p-Methoxycinnamate, Oxybenzone Zinc Oxide, Avobenzone, Dioxybenzone Among the organic sunscreens such as Sulisobenzone, Mexoryl SX, Aminobenzoic acid (PABA), Trolamine Salicylate and Padimate-0, Use any one or more selected.

The ceramic may be a pulverized ceramic powder having a mesh size of 300 to 400 mesh and a ceramic having a particle size of 300 to 400 mesh may be a general pulverizer. When the ceramic has a particle size of 300 mesh or less, the outer layer 11 and the middle layer 12) The surface roughness of the film is poor, and when the particle size is 400 mesh or more, the workability is good, but the processing cost is high because special precision milling is required.

The ceramic is composed of oxides, carbides, and nitrides formed by combining metal elements such as silicon (Si), aluminum (Al), titanium (Ti), and zirconium (Zr) with oxygen, carbon, nitrogen, Silica, magnesium oxide, sodium oxide, calcium oxide, titanium dioxide, zirconia, and silicon carbide. Silicon nitride, barium titanate, and the like.

The ceramic powder is prepared by pulverizing a ceramic with a pulverizer to a particle size of 300 to 400 mesh, and then mixing the powder with alumina, silicon oxide, magnesium oxide, sodium oxide, calcium oxide, Titanium dioxide, zirconia, silicon carbide. Silicon nitride, and barium titanate to prepare a ceramic powder.

The warming agent may be selected from the group consisting of sbestos heat insulating material, istomaceous earth heat insulating material, rock wool heat insulating material, calcium silicate heat insulating material, magnesium carbonate a carbonate heat insulating material, a glass wool heat insulating material, and a blast furnace slag heat insulating material.

In order to increase the heat insulation efficiency when the present film 10 for agricultural film is used for the sake of the present invention, it is preferable that the heat retaining agent is formed by conducting or radiating the inner and outer heat of the agricultural film, Thereby preventing external heat from being transmitted to the inside, thereby providing a heat-shielding effect and a cold prevention effect.

The room temperature of the concentrated film is intercepted by the main heating agent of the middle layer and absorbed into the room so that the room temperature of the concentrated film does not decrease even during the winter season.

The present invention shields about 97% of the sunlight by the aluminum of the outer layer 11 and the middle layer 12 and the middle layer 12 of the middle layer 12 to block the upward movement of the geothermal heat in winter It is reflected to the lower part and the warmth of the geothermal heat is good, and in the summer, the outside temperature is blocked from being transferred to the inside of the farm to cool the inside of the farm.

The pigments include coarse particles or generally known metallic pigments, inorganic pigments and organic pigments in powder form. The metallic pigments include aluminum pigments, bronze pig pigments and ferric pigments. The inorganic pigments include carbon black, Cobalt green, Cobalt blue, Yellow ocher, Oxidize red iron, Viridian, Cadmium yellow and Ultra marine. blue, titanium dioxide (TiO2) or iron oxide green, and the organic pigment is selected from the group consisting of Hansa yellow.

The pigment is powdered and used to coat ethylene vinyl acetate copolymer (EVA) or low density polyethylene (LDPE) by vacuum deposition before the powder is mixed and melted in the resin, or mixed and melted in the resin in powder form.

The color of the middle layer 13 is determined by the pigment and the preferred color of the middle layer 13 is different from that of the pigment. Therefore, the pigment can be colored in various colors.

The water repellent agent may be a commonly known water repellent agent and an oil repellent agent. The water repellent agent may be a water repellent agent and an oil repellent agent. The water repellent agent may be selected from the group consisting of aluminum, silane, silicone or urethane, (EVA) or low density polyethylene (LDPE), or mixed and melted in the resin in powder form.

Even if the present invention is used for the agricultural film due to the water repellent agent, water droplets are not formed on the inner surface of the film even during the winter season.

Since the aluminum, ultraviolet screening agent, ceramic, heat preserving agent, pigment or water repellent agent powder may be aggregated together, a dispersant may be further added to prevent the particles from aggregating in the composition uniformly. But the present invention is not particularly limited thereto and any dispersant conventionally used in this field can be used.

The compositions for Examples 1 to 6 of the film for the present invention are shown in Table 1 below.

Composition status division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6
Outer layer

EVA 37 45 55 32 41 50 mPE 37 45 55 32 41 50 aluminum 7 11 14 6 9 12 Sunscreen 11 15 19 10 13 17

Middle layer


EVA 33 40 49 28 37 44 mLLDPE 33 40 49 28 37 44 aluminum 7 11 14 6 9 12 Sunscreen 11 15 19 9 13 17 ceramic 6 9 9 5 7 8 Warming agent 6 9 9 5 7 8

Inner layer

EVA - - - 29 38 47 LDPE - - - 29 38 47 Sunscreen - - - 10 14 18 Pigment - - - 10 12 14 Water repellent agent - - - 8 10 12

The compositions according to Examples 1 to 6 were mixed, melted and extruded into a film, irradiated with light on the extruded film for agricultural film to measure the amount of heat on the front and rear sides of the film, The light transmittance was evaluated.

Light transmittance (%) = [(heat quantity before film permeation-heat quantity after film permeation) / heat quantity before film permeation] × 100

The measured light transmittances for Examples 1 to 6 are shown in Table 2 below.

Light transmittance (%) division Wavelength (nm) Example 1 Example 2 Example 3 Example 4 Example 5 Example 6
UV-rays
200 1.7 1.5 1.2 1.8 1.6 1.5 300 2.1 1.7 1.2 2.2 1.9 1.5 400 2.1 1.7 1.1 2.3 1.8 1.4
infrared ray
1,000 27.3 25.6 24.8 28.7 26.8 26.5 2,000 30.3 28.2 27.5 30.5 28.3 28.3 3,000 34.6 32.0 30.8 36.8 33.3 31.6

The light transmittance of the present invention was 1.1 to 2.3% in ultraviolet rays, and the ultraviolet rays were well shielded, and the infrared rays were transmitted at 24.8 to 36.8%.

The compositions according to Examples 1 to 6 were mixed and melted and extruded into a film to evaluate physical properties of the extruded film for agricultural film.

(1) Melt index

Gt; 190 C < / RTI > and 2.16 kg under the conditions of ASTM D1238.

(2) Density

It was measured by Density Gradient Column according to ASTM D1505 method.

(3) Coefficient of dynamic friction

The coefficient of dynamic friction of the film surface was measured by the ASTM D1904 method.

(4) Bending test

The flexural modulus of the specimen of the KS M3008 standard was measured with an Instron 4400 series Instron 4400 series at a span distance of 50 mm and a crosshead speed of 2.5 m / min.

(5) Tensile test

Tensile strength was measured under the conditions of a load cell of 50 kgf in Instron 4400 series manufactured by INSTRON UTM as a test piece of KS M3006 standard.

(6) Impact strength

Izod impact strength was measured on a rectangular test piece (63 mm x 12 mm x 5 mm) using an impact tester (Model 863, Ueshima Seisakusho Co., Ltd.) according to JIS K7110 standard.

(7) Film appearance

The appearance of the film was evaluated qualitatively by the inventor in terms of sensory evaluation. When the appearance of the film was smooth, there was no protrusion in the outer surface of the film. In the case where the surface was not smooth, it was usually expressed as defective when there was a slight protrusion in the outer surface of the film .

The physical properties measured for Examples 1 to 6 are shown in Table 3 below.

Evaluation results of film properties division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Melt Index
(MI: g / 10 min) 4.0 to 5.9 3.7 to 5.3 3.1 ~ 4.9 4.6 to 8.4 4.2 to 8.0 2.8 to 7.5 Density (g / cm3) 0.961 to 0.994 0.978 to 1.010 0.992 to 1.240 0.988 to 0.998 0.744 to 0.997 0.823 to 1.211 Coefficient of friction 0.90 0.78 0.67 0.85 0.71 0.59 Flexural modulus
(Kgf / cm2) 13,062 14,223 15,288 13,874 13,450 14,427 The tensile strength
(Kgf / cm2) 342 374 388 361 350 379 Impact strength
(J / m) 61 74 86 70 79 81 Film appearance Good Good Good Good Good Good

The melt index of the present invention is 2.8 to 8.4 g / 10 min. The density is 0.744 to 1.211 g / cm 3. The coefficient of dynamic friction is 0.90 or less. The flexural modulus is 13,062 kgf / cm 2 or more. The tensile strength is 342 kgf / And the appearance of the film was good. Thus, the film for agricultural use of the present invention was superior to the film comprising only the polyethylene-based film as a whole.

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Therefore, the scope of the present invention should not be construed as being limited to the embodiments described, but should be determined by equivalents to the appended claims, as well as the following claims.

10: film for concentration film 11: outer layer
12: middle layer 13: inner layer

Claims (8)

In the film for agricultural film,
28 to 58 parts by weight of ethylene vinyl acetate copolymer (EVA), 28 to 58 parts by weight of metallocene polyethylene (mPE), 5 to 15 parts by weight of aluminum of 300 to 400 mesh powder, 9 to 20 parts by weight of an ultraviolet screening agent And an outer layer including a part of the outer layer;
25 to 52 parts by weight of ethylene vinyl acetate copolymer (EVA), 25 to 52 parts by weight of metallocene linear low density polyethylene (mLLDPE), 5 to 15 parts by weight of aluminum of 300 to 400 mesh size powder, To 20 parts by weight, a ceramic layer having a particle size of 300 to 400 mesh and 5 to 10 parts by weight of a thermal insulating material;
25 to 51 parts by weight of an ethylene vinyl acetate copolymer (EVA), 25 to 51 parts by weight of a low density polyethylene (LDPE), 8 to 20 parts by weight of an ultraviolet blocking agent, 10 to 15 parts by weight of a pigment and 6 to 14 parts by weight of a water- Wherein the inner layer is formed of a film containing a metal oxide.
delete delete delete The method according to claim 1,
The ceramic may be selected from the group consisting of alumina, silicon oxide, magnesium oxide, sodium oxide, calcium oxide, titanium dioxide, zirconia, silicon carbide silicon nitride, silicon carbide, silicon nitride, and barium titanate.
The method according to claim 1,
The warming agent may be selected from the group consisting of a sbestos heat insulating material, a rock wool heat insulating material, a glass wool heat insulating material and a blast furnace slag heat insulating material. Wherein the film comprises at least one film.
delete delete

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