KR100932707B1 - Strengthened agricultural laminated film and its manufacturing method - Google Patents

Abstract

The present invention relates to an agricultural laminated film, the spunbond non-woven fabric and the breathable film and the mesh reinforcing film laminated to prevent the evaporation of water, to improve the strength, and to maintain the air permeability film. More specifically, the present invention is an adhesive particle is applied in the form of embossed by spraying the molten spray at a high temperature of about 280 ℃ using an amorphous spray on the breathable film, by bonding a spunbonded fabrics and a mesh reinforcement film The adhesive strength is improved, and to provide an agricultural laminated film that can improve the light transmittance.

Agricultural film, nonwoven fabric, spunbond, mesh reinforcement film, hot melt

Description

Strengthened agricultural laminated film and its manufacturing method {REFLECTION FILM FOR CULTIVATING PLANT AND MANUFACTURING METHOD THEREOF}

The present invention relates to a strength-reinforced agricultural laminated film, the spunbond non-woven fabric and mesh reinforcement film and breathable film to prevent the evaporation of moisture, to maintain the air permeability, as well as to the film produced to enhance the strength It is about.

Spunbond nonwoven fabrics are used for disposable medical gowns and gloves because they can act to prevent invasion of bacteria such as bacteria or to prevent contamination. The spunbond nonwoven fabric of this kind may be manufactured using a meltblown method, or the like, and a spunbond nonwoven fabric may be used inside and a meltblown method may be used on the outer cover to composite a web having excellent touch. Recently, the demand for agricultural spunbond nonwoven fabrics is increasing with the explosive use of vinyl houses. Spunbond nonwoven fabric has a large internal space for its structure, so it is easy to mass-produce small items because of its excellent thermal insulation and simple production method.

However, when a spunboard nonwoven fabric made of polyester resin is used as an agricultural vinyl house, the polymer chain is cut by ultraviolet rays and mechanical properties are degraded, or the structure of dyes and pigments present with the polymer chain is destroyed, causing discoloration or discoloration. There is a problem.

In general, the wavelength of the ultraviolet rays to lower the physical properties of the polyester fiber corresponds to 300 ~ 400nm and polyethylene terephthalate itself has some degree of UV protection. It absorbs ultraviolet rays having a wavelength of 320 nm or less and has ultraviolet ray blocking property, but does not have blocking property against ultraviolet rays having a wavelength higher than that. When the wavelength of the ultraviolet ray is 300 to 400nm, the molecular chain of the polymer is most affected, resulting in degradation or durability degradation due to ultraviolet rays.

Therefore, various studies have been conducted to improve the weather resistance of polyester spunbond nonwoven fabrics.

A typical prior art for improving the weather resistance of polyester spunbond nonwovens is the addition of sunscreens in polymerization and spinning processes. However, such a method has a problem in that the amount of the sunscreen is limited, so only the effect of temporarily blocking the UV light can be expected.

For example, when sunscreens are introduced in a fiber spinning process, sunscreens should be selected that do not change their structure even at high temperatures and that the sunscreen properties can be maintained in the final product. Sunscreens with these characteristics are not only rare but also expensive and uneconomical. In addition, there is a problem in that the equipment is complicated because the additional sunscreen is required to be evenly distributed during radiation.

Meanwhile, a method of improving weather resistance by manufacturing a polyester spunbond nonwoven fabric and then immersing it in a solution containing a sunscreen is also known. However, in this case, the sunscreen is stuck to the surface of the spunbond so that the weather resistance improvement effect is not permanent. have.

Therefore, when using a conventional non-woven fabric is weak to moisture, and aging by sunlight, so that after one year the tissue of the resin was destroyed, it was impossible to reuse.

In order to improve this disadvantage, a method of laminating with a breathable film has been disclosed, but a method of laminating with a nonwoven fabric in a molten state when manufacturing a breathable film is disclosed in Korean Patent No. 10-0514905, which is a disadvantage of nonwoven fabric In order to improve the usability for a long time, in order to impart breathability, a process of imparting breathability by passing a breathable film laminated between the nonwoven fabric and the elastic pattern roll and an elastic roll was required. It was difficult to give excellent breathability because it is a state of being fully laminated only as a whole.

In the case of agricultural films, while providing air permeability to the crop, the tensile strength is excellent, and the main function is to provide sufficient sunlight, it was necessary to produce agricultural films to improve this function.

The present invention is applied to the adhesive particles in the form of a spot by melting and spray spraying a solvent-free hot melt adhesive to a breathable film at a high temperature in order to solve the problems of the prior art and the like described above, spunbonded fabrics and mesh By adhering the reinforcing film to improve the adhesive strength, while maintaining the breathability, while preventing the evaporation of moisture, improve the light transmittance, to provide an agricultural laminated film reinforced with strength.

In addition, the present invention improves the physical properties of the film by using additives such as UV stabilizers, antioxidants, etc. in the manufacture of breathable film to delay the oxidation by light such as ultraviolet rays, at least 3 to 4 years The purpose of the present invention is to provide an agricultural laminated film that is intended to contribute to the development of agriculture by improving economic efficiency by enabling reuse of precision.

In addition, the present invention is not only the mesh reinforcement film but also made the breathable film of the intermediate layer in the white, as well as the transmittance of the light, by increasing the irradiation amount of sunlight to fruit water by the light reflection effect of the surface pulls the harvest time of the fruit, It aims at improving sugar content.

In addition, the present invention is used by laminating the film in three layers, by laminating a breathable film between the spunbond non-woven fabric and the mesh reinforcement film to not only prevent the evaporation of moisture, but also to improve the film strength to grow weeds and the like. The purpose is to prevent them from doing so.

The present invention relates to an agricultural film, and more specifically, to increase the durability and strength by laminating a spunbond nonwoven fabric, a breathable film and a mesh reinforcement film in three layers, and improves the adhesive strength by using a non-solvent-type hot melt adhesive when laminating The present invention relates to an agricultural film characterized by improving the air permeability and improving the service life of the film compared to a conventional agricultural film.

In more detail, the present invention,

A mesh reinforcing film layer prepared by cross-linking filaments made of polypropylene resin with each other and thermally pressing them together with a polyethylene film or by intersecting a filament having an inner layer made of a high density polyethylene resin and an outer layer made of a low density polyethylene resin;

Solvent-free hot melt adhesive is melt-sprayed on top of the mesh reinforcing film layer hot melt adhesive layer laminated in the form of spots;

Breathable film layer using a compound composition for breathable film comprising a polyethylene-based resin and an inorganic filler, an antioxidant and a UV stabilizer laminated on top of the hot melt adhesive layer;

A hot melt adhesive layer in which a solvent-free hot melt adhesive is melt-sprayed on the top of the breathable film layer and laminated in a spot shape;

A spunbond nonwoven layer laminated on top of the hot melt adhesive layer;

It relates to an agricultural laminated film characterized in that the laminated sequentially.

Hereinafter, each structure of this invention is demonstrated concretely.

1) Spunbond Nonwoven Fabric

In the present invention, the spunbond nonwoven fabric means a nonwoven fabric produced by a conventional spunbond method, but is not limited to any one of resins selected from polyester, nylon, polyethylene, and polypropylene, and more preferably polypropylene resin. It is preferable to use the spun bond which used, and what was manufactured from the nonwoven fabric by the conventional spun bond method is used. More preferably, it is preferable to use a spunbond nonwoven fabric having a thickness of 0.1 to 1 mm, a tensile strength of 5 to 30 kg / 5 cm, and an elongation of 60 to 100% because of excellent strength when laminating as an agricultural film. As a nonwoven fabric which has such a physical property, Toray Saehan Co., Ltd. ZESBON is for example.

In addition, SMS (Spunbond + Melt Blown + Spunbond), SMMS (Spunbond + Melt Blown + Melt Blown + Spunbond), and SSMMS (Spunbond + Spunbond) are a combination of a spunbond nonwoven fabric and a meltblown nonwoven fabric. It is also possible to use nonwoven fabrics such as + meltblown + meltblown + spunbond.

The present invention has a soft texture, such as fiber by using such a spunbond nonwoven fabric, excellent strength, excellent weed suppression effect, there is no need to use herbicide pesticide, there is an effect of reducing the material cost and labor force, excellent breathability Smooth supply of oxygen can achieve the effect of improving the commerciality of the fruit.

However, when using only such a spunbond non-woven fabric is weak to moisture, tearing, and oxidized by light, there is a problem that the strength is weakened, the present invention improves these problems, the agricultural film that can be reused for 3 to 4 years As a result of the research to provide the result, it has been found that laminating the breathable film and the spunbond nonwoven fabric can improve the moisture resistance while maintaining the breathability.

In particular, the present invention was able to improve the strength and resistance to moisture by laminating a spunbond nonwoven fabric and a breathable film, and melted at a high temperature by spraying a non-solvent-type hot melt adhesive at a high temperature and laminated in a spot form for maximum breathability It was found that while maintaining the adhesive strength is improved.

In addition, the present invention was completed by the invention that the production of the breathable film by adding an antioxidant and a UV stabilizer can be further improved the effect of preventing the oxidation by sunlight.

In general, the nonwoven fabric used for agriculture is black, but the color of the spunbond nonwoven fabric in the present invention is advantageous in that the sugar content is increased by increasing the dose of fruit due to the reflection of light. In addition, as the irradiation dose increases, there is an effect that can shorten the fruiting date of the fruit.

2) Compound composition for breathable film

In the present invention, the compound composition for the breathable film may use a composition comprising a polyolefin resin and an inorganic filler, an antioxidant and a UV stabilizer, specifically, based on 100 parts by weight of an inorganic filler, 20 to 250 parts by weight of a polyolefin resin It is preferable to use a composition containing 0.1 to 20 parts by weight of an antioxidant, and 0.1 to 20 parts by weight of a UV stabilizer, and to coat the surface of the inorganic filler to improve the miscibility of the inorganic filler and the polyolefin resin. It is also possible. That is, during the stretching process, while improving the dispersibility of the inorganic filler and the polyolefin, which is a matrix resin, pore generation is promoted in the partially uncoated portion, and thus, many pores are easily expressed while maintaining the existing mechanical properties as a whole. To secure.

In another aspect, the present invention is to provide a breathable film characterized in that the sheet formed by melt molding the obtained compound composition for breathable film is stretched in the range of 1.5 times to 36 times the area draw ratio to form pores.

In addition, the present invention may further add a composition for improving the whiteness of the composition, the breathable film according to the present invention is preferably made of white. In the present invention, it is preferable that not only the spunbond nonwoven fabric but also the breathable film is made of white to accelerate fruit deletion by light reflection and increase the sugar content of the fruit.

In the present invention, the polyolefin resin is a low-density polyethylene, a linear low-density polyethylene, a medium-density polyethylene, and a homopolymer including a high density polyethylene or a copolymer based on ethylene, a polypropylene homopolymer or a copolymer based on propylene and a polybutene Preference is given to using at least one compound selected from the group consisting of:

In the present invention, the inorganic filler is calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, calcium chloride, calcium sulfate, aluminum hydroxide, zinc oxide, magnesium hydroxide, titanium oxide, alumina, mica, asbestos powder, zeolite, One or more selected from the group consisting of clay silicate may be used, and the average particle diameter of the inorganic filler is not limited, but preferably using an average particle diameter of 1 ~ 200㎛ improves the surface smoothness of the film and physical properties during manufacture . If the particle size is less than 1 μm, since the particle size is too small, dispersibility decreases when dispersing with the resin, so that some agglomeration may occur and defects may occur after the film is manufactured. When the film is torn easily may occur.

The coating agent for coating the inorganic filler of the present invention has a compatibility enough to coat a part of the inorganic filler, the weight average molecular weight 30,000 or less produced by extraction by boiling n-hexane when the high-density polyethylene-based resin is prepared, melting An ethylene-based polymer having an index (190 ° C., 2.16 Kg) of 50 g / 10 min or more is used. These ethylene-based polymers usually occur as cakes in the process, but if they are pulverized well, they have a wax-like shape, and due to the inclusion of ethylene-based polymer components with lower molecular weights of hundreds to thousands, they have some flowability even at tens of degrees Celsius. When it reaches about 100 ° C. or more, it has better flowability, and the coating property is expressed to some extent through the mixing and the high speed stirring process for the inorganic filler in the high speed mixer. However, since the ethylene-based polymer is lipophilic, and unlike high-fatty acids having both hydrophilicity and lipophilic property, coating property is poor, it is possible to obtain an inorganic filler having a partially coated structure originally intended, thereby completing the present invention. have.

The ethylene-based polymers generally have a molecular weight distribution due to the resin properties when the high density polyethylene resin is prepared by a Ziegler-Natta catalyst or a chromium catalyst system, and thus a low molecular weight component is naturally produced. Films and containers that require high molecular weight are extracted and removed by boiling n-hexane in that they may adversely affect resin properties. The ethylene polymer obtained in this removal process has a very wide molecular weight distribution. It is a low molecular weight component with no special use, so it is treated as industrial waste and its treatment is very difficult. Recently, a wax manufacturer requiring a narrow range of molecular weight distribution, for example, has been attempted to separate and purify it again. However, it is still economically processed at almost the waste level. Such a very inexpensive, large and stable weight average molecular weight of less than 30,000, ethylene polymer of more than 50g / 10min melt index (190 ℃, 2.16Kg) as a surface modification treatment agent of the inorganic filler as a coating agent suitable for the purpose of the present invention Used.

In another embodiment of the present invention, as a kind of coating agent for the inorganic filler as described above, it is more effective to use a mixture of saturated fatty acids in the range of 5 to 30% by weight of saturated fatty acid in the melting point 40 ~ 80 ℃ range. In other words, saturated fatty acid having low melting point and hydrophilicity simultaneously dissolves at low temperature at the beginning of agitation, and contributes more effectively to dispersion than lipophilic ethylene-based polymers for hydrophilic inorganic fillers. So it is better to use a small amount added. However, when the mixing ratio is more than 30% by weight, the coating property is so good that it is difficult to form a target partial coating structure, and the economy is poor due to the high cost. In addition, when saturated fatty acids exceed the melting point of 80 ° C., an ethylene polymer component having flowability at tens of ° C. first contributes to the initial dispersing phase, and is intended to improve the performance of dispersing promotion even though the economy is poor. Not so desirable. Specific examples of saturated fatty acids in the range of 40 ° C to 80 ° C include lauric acid with a melting point of 45 ° C, myristic acid with two melting points of 54 ° C and 58 ° C, palmitic acid with a melting point of 63 ° C, and stearic acid with a melting point of 71 ° C. Etc. can be mentioned.

As the antioxidant, those containing phenol, phosphoric acid and sulfur may be used. Examples of the phenolic antioxidant used include 2,6-di-tert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-di-tert- Butyl-4-hydroxyphenyl) propionate, distearyl (3,5-di-tert-butyl-4-hydroxybenzyl) phosphate, thiodiethylene glycol bis [(3,5-di-tertiary) -Butyl-4-hydroxyphenyl) propionate], 1,6-hexamethylene bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,6-hexa Methylene bis [(3,5-di-tert-butyl-4-hydroxyphenyl) propionamide], 4,4'-thiobis (6-tert-butyl-m-cresol), 2,2'- Methylene bis (4-methyl-6-tert-butylphenol), 2,2'-methylene bis (4-ethyl-6-tert-butylphenol), bis [3,3-bis (4-hydroxy- 3-tert-butylphenyl) butyric acid] glycol ester, 4,4'-butylidene bis (6-tert-butyl-m-cresol), 2,2'-ethylidene bis (4,6-di- Tert-butylphenol), 2,2'-ethylidene bis (4-tert-butyl-6-tert-butylphenol), 1,1,3-t (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, bis [2-tert-butyl-4-methyl-6- (2-hydroxy-3-tert-butyl-5) -Methylbenzyl) phenyl] terephthalate, 1,3,5-tris (2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate, 1,3,5-tris (3 , 5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -2,4 , 6-trimethylbenzene, 1,3,5-tris [(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tetrakis [methylene-3- ( 3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, 2-3-butyl-4-methyl-6 (2-acryloyloxy-3-tert-butyl- 5-methylbenzyl) phenol, 3,9-bis 1,1-dimethyl-2-[(tert-butyl-5-methylbenzyl) propionyloxy] ethyl-2,4,8,10-tetraoxa Spiro [5,5] undecane, triethyleneglycol bis [(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], and the like. .

Examples of the phosphoric acid antioxidant include tris (nonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris [2-tert-butyl-4- (3-tert-butyl) -4-hydroxy-5-methylphenylthio) -5-methylphenyl] phosphite, tridecylphosphite, octyldiphenylphosphite, di (decyl) monophenylphosphite, monodecyldiphenylphosphite, mono (dinonyl Phenyl) bis (nonylphenyl) phosphite, di (tridecyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, di (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-3 Tert-butylphenyl) pentaerythritoldiphosphate, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritoldiphosphite, tetra (tridecyl) isopropylidene-diphenyldiphosphite, tetra (C12-16 mixed alkyl) -4,4'-n-butylidene bis (2-tert-butyl-5-methylphenol) diphosphite, hexa (tridecyl) 1,1,3-tris (2- methyl 4-hydroxy-5-tert-butylphenyl) butane triphosphite, tetrakis (2,4-di-tert-butylphenyl) biphenylene diphosphite, 2,2'-methylene bis (2, 4-di-tert-butylphenyl) octyl) phosphite and the like.

Examples of such sulfur-containing antioxidants include dialkyldithiopropionates [e.g. dilauryl, dimyristyl or distearyl esters of thiodipropionic acid], [beta] -alkylmercaptopropionic acid esters of polyol [e.g. pentaerythritol Tetra (β-dodecylmercaptopropionate)].

In the present invention, the UV stabilizer is 2,2,6,6-tetramethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl-stearate, 2 , 2,6,6-tetramethyl-4-piperidinylbenzoate, N- (2,2,6,6-tetramethyl-4-piperidyl) dodecyl succinic acid imide, 1- (3, 5-di-tert-butyl-4-hydroxyphenyl propionyloxyethyl) -2,2,6,6-tetramethyl-4-piperidyl- (3,5-di-tert-butyl-4 -Hydroxyphenyl) propionate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperi Dill) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) -2-butyl-2- (3,5-di-tert-butyl-4-hydroxybenzyl ) Maloate, N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylene-diamine, tetra (1,2,2,6,6-pentamethyl-4- Piperidyl) butanetetracarboxylate, tetra (2,2,6,6-tetramethyl-4-piperidyl) butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4- Pipe Dill) di (tridecyl) butanetetracarboxylate, bis (2,2,6,6-tetramethyl-4-piperidyl) -di (tridecyl) butanetetracarboxylate, 3,9-bis [1, 1-dimethyl-2- [tris (2,2,6,6-tetramethyl-4-piperidyloxycarbonyloxy) butylcarbonyloxy] ethyl] -2,4,8,10-tetraoxaspero [5,5] undecane, 3,9-bis [1,1-dimethyl-2- [tris (2,2,6,6-tetramethyl-4-piperidyloxycarbonyloxy) butylcarbonyloxy ] Ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, 1,5,8,12-tetrakis 4,6-bis [N- (2,2,6,6- Tetramethyl-4-piperidyl) butylamino] -1,3,5-triazin-2-yl-1,5,8,12-tetrazadodecane, 1- (2-hydroxyethyl) -2, 2,6,6-tetramethyl-4-piperidinol / succinic acid dimethyl ester condensate, N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylene-diamine / Dibromoethane condensates and the like. UV stabilizers have no effect when used in too small amounts and adversely affect the transparency of the film when used in excessive amounts.

In the present invention, as necessary for the compound composition for breathable film, resin additives commonly used, such as plasticizers, lubricants, antistatic agents, pigments, ultraviolet absorbers, anti-fogging agents (anti-fogging agents), anti-foaming An antihaze agent, a heat stabilizer, an antiblocking agent, a dye, a white enhancer, a desiccant, a heat stabilizer, a fluorescent agent, and other heat insulating agents may be added.

The following discloses more specifically aspects of the compound composition for breathable film that can be used in the present invention.

One embodiment used in the present invention is a weight average molecular weight of 5000 ~ 30,000 produced by boiling n-hexane when producing a high-density polyethylene resin based on 100 parts by weight of inorganic filler, melt index (190 ℃, 2.16Kg) 50 ~ 100 parts by weight of an inorganic filler coated with an ethylene polymer obtained by mixing, rapidly stirring and dispersing 1 to 10 parts by weight of an ethylene polymer of 100 g / 10 min and a polyolefin resin having a melt index (190 ° C., 2.16 Kg) of 1 to 10 g / 10 min. 20 to 250 parts by weight, 0.1 to 20 parts by weight of antioxidant, 0.1 to 20 parts by weight of UV stabilizer is used.

In another embodiment, a weight average molecular weight of 5000 to 30,000 and a melt index (190 ° C., 2.16 Kg) of 50 to 100 g / 10 min, which are extracted by boiling n-hexane to produce 100 parts by weight of an inorganic filler, is produced by boiling n-hexane. 100 parts by weight of an inorganic filler coated with an ethylene polymer obtained by mixing, rapidly stirring and dispersing 1 to 10 parts by weight of a mixture composed of 70 to 95% by weight of an ethylene polymer and 5 to 30% by weight of saturated fatty acid having a melting point of 40 to 80 ° C. And a melt index (190 ° C., 2.16 Kg) of 20 to 250 parts by weight of polyolefin resin in the range of 1 to 10 g / 10 min, 0.1 to 20 parts by weight of antioxidant, and 0.1 to 20 parts by weight of UV stabilizer can be used.

3) Mesh reinforcement film

In the present invention, the mesh reinforcement film is a plastic film and a porous film is laminated, and the polyethylene film is adhered to a film prepared in the form of a mesh by thermally compressing the filaments made of polypropylene resin to each other, the present invention is polypropylene Not only can the effect of improving the strength by the mesh can be achieved, the adhesion with the breathable film can be improved by the polyethylene film adhered to one surface. Accordingly, even when heated to a low temperature during thermal bonding, the adhesive was able to achieve improved adhesiveness while maintaining breathability. Examples of such mesh reinforcement films include Nisseki Warifu (trademark, Nisseki Jushi Products Co.), Diacloth (trademark, Diatex Co.), Crenet (trademark, Kurare Co.), or Sofunet (trademark, Shin-nihon Sofu Co.) There is this.

Alternatively, a mesh reinforcing film made by intersecting a filament having an inner layer made of a high density polyethylene resin and an outer layer made of a low density polyethylene resin with each other may be used, wherein the filament may be manufactured in a plate shape or a circular shape. In case of the plate type, the inner layer made of high density polyethylene resin and both sides of the inner layer, that is, the upper and lower parts are made of low density polyethylene resin, and the circular case is made of the inner layer made of high density polyethylene resin and the low density polyethylene resin sheath structure surrounding the same. An example of such a mesh reinforcement film may use the MELTAC series of HAGIHARA.

The mesh reinforcement film has a basis weight of 15 ~ 40g / ㎡, thickness of 0.05 ~ 0.15mm, MD direction tensile strength of 90 ~ 230 N / 5cm, CD direction tensile strength of 90 ~ 230 N / 5cm It is suitable to use the final physical properties.

4) Solvent-free hot melt adhesive

In the present invention, the solvent-free hot melt adhesive is a polyolefin resin selected from polyethylene, polypropylene, polybutylene, ethylene-propylene copolymer, propylene-butylene copolymer, ethylene-propylene-butylene terpolymer Use it.

50 to 55% by weight of at least one polyolefin resin selected from polyethylene, polypropylene, polybutylene, ethylene-propylene copolymer, propylene-butylene copolymer, ethylene-propylene-butylene terpolymer, petroleum resin (C5 Petroleum resin, C5 / C9 petroleum resin, C9 petroleum resin, hydrogenated C5 petroleum resin, hydrogenated C5 / C9 petroleum resin, hydrogenated C9 petroleum resin, etc.), terpene-based resins (hydrogenated phenolated terpene resins, phenolized terpene resins, hydrogenated terpene resins) Etc.), 40 to 45 wt% of any one or more adhesive enhancers selected from rosin resins (rosin resins, hydrogenated rosin resins, esterified rosin resins, hydrogenated esterified rosin resins, aromatic base oils, naphthenic oils) , Paraffin-based oil may contain 5 to 10% by weight of at least one softening oil selected from.

When applying the hot melt adhesive according to the present invention by spray coating method in the form of spots in the breathable film to maintain the oxygen permeability to the maximum, it was possible to improve the adhesion compared to the conventional grid-like adhesive method.

In addition, the solvent-free hot melt adhesive is applied by using a spray after melting and heating to 200 ℃ or more, preferably 250 ~ 300 ℃.

5) Preparation of Film Laminate

Referring to Figure 1 with respect to a method for manufacturing the agricultural laminated film according to the present invention,

A) The extruder melt-extruded compound composition for breathable film in a pellet state, and the original sheet obtained through a T-die or a circular die is stretched at least 1.5 times the area stretching ratio at a temperature of not less than the glass transition point or less than the melting point, and the breathable film (10) Preparing a;

B) melting and spray-spraying a solvent-free hot melt adhesive 20a on one surface of the stretched breathable film 10;

C) adhering the mesh reinforcing film (30a) to the surface on which the hot melt adhesive (20a) is applied in the breathable film (10);

d) rolling using a roller 40a;

e) spray-melting and spraying a solvent-free hot melt adhesive 20b on the opposite side to which the mesh reinforcing film 30a is adhered in the breathable film 10;

f) adhering the spunbond nonwoven fabric 30b to the surface to which the hot melt adhesive 20b is applied;

g) rolling using a roller 40b;

It is characterized by being manufactured by.

In more detail with respect to the production method, in the preparation of the compound composition for breathable film is kneading the mixture obtained by adding and mixing a polyolefin resin, an antioxidant, a UV stabilizer and a common additive to the inorganic filler, a conventionally known device For example, a conventional single screw extruder, a twin screw extruder, a mixing roll, a balm mixer, a kneader, etc. are performed suitably. The kneaded compound composition is then pelletized. The compound composition is put into a hopper to form a disc sheet according to a conventional film forming apparatus and molding method by extrusion processing. If inflation molding using a circular die or extrusion molding with a tee die is appropriately employed, good. Next, the original sheet molded by the extrusion method is uniaxially stretched in the range of 1.2 times to 6.0 times, preferably 1.5 times to 5 times, at a temperature between the glass transition point and the melting point or less. At this time, if the elongation point is less than the free point, the film cannot be stretched and elongated before the elongation exceeds the yield point. If the elongation point is exceeded, it is impossible to obtain satisfactory breathability due to the flow of the molecular chain. In addition, when the draw ratio is less than 1.2 times, sufficient air permeability cannot be obtained, and when the draw ratio is more than 6 times, breakage phenomenon occurs frequently during stretching and a film cannot be stably obtained. Subsequently, biaxial stretching is performed within the same stretching temperature and elongation conditions as in the case of the monoaxial stretching to obtain a biaxially stretched breathable film. As described above, even a uniaxially stretched film which is not uniaxially stretched but uniaxially stretched, a film meeting the object of the present invention can be obtained. That is, the breathable film according to the present invention can be produced by either uniaxial or biaxial stretching, and it is preferable to stretch the total area stretching ratio to be in the range of 1.5 to 36 times. If the area draw ratio is less than 1.5 times, sufficient air permeability cannot be obtained, the film is hard, and the touch is degraded. If the area is over 36 times, the air permeability is excellent, but there is a possibility that the mechanical strength is significantly degraded. In order to improve the dimensional stability, the film after extending | stretching may heat-fix.

In addition, the breathable film obtained by the present invention may be subjected to a known embossing treatment in order to improve the feel and appearance.

Next, spray-free solvent-free hot melt adhesive 20a is applied to one surface of the manufactured breathable film 10. At this time, a small spot-type adhesive is formed on the surface of the breathable film by spray application, and thus does not interfere with breathability. It will be possible to improve. The mesh reinforcement film 30a released from the roller is adhered to the surface on which the hot melt adhesive is applied, and is rolled by the roller 40a to be bonded.

Next, after spray coating the hot melt adhesive 20b on the opposite side in the same manner as above, the spunbonded nonwoven fabric 30b released from the roller is adhered and pressed by the roller 40b and finally wound on the winding roller 50. It is wound.

This manufacturing method produces three layers of agricultural laminated film in which a mesh reinforcement film and a spunbond nonwoven fabric are laminated on both sides of a breathable film, and has excellent adhesive strength without impairing breathability by spray-spraying a solvent-free adhesive. It is possible to achieve the durability and tensile strength by the spunbond nonwoven fabric of both sides.

In addition, the agricultural film of the present invention is made of one side is white, the other side is made of black, so that the black side to the bottom surface, and the white side to face the sky, the reflection of sunlight and fruit By reflecting light into the water to increase the growth of the fruit, the effect of preventing the evaporation of moisture on the bottom is improved.

5) process of forming emboss

According to the present invention, the embossed film may be formed by passing the agricultural laminated film laminated in the three layers through a roller on which an emboss is formed. When embossed on the surface, when packaging fruits such as fruit, friction with the surface of the fruit is reduced, oxygen is transferred to the surface to allow the fruit to breathe, thereby improving safety during storage.

Agricultural paper according to the present invention can prevent the loss of soil and prevent flowers, fruit trees and pestilence, and durable and less aging in moisture and sunlight, can be reused for about 3-4 years, water evaporation occurs in summer It can be prevented, and it is laminated with three layers to increase the strength, so that weeds can be prevented from growing, and one side of the film is made of white to reflect sunlight coming to the floor, so the reflected light on the bottom surface is not affected by fruit water. Concentration increases fruit growth and increases the sugar content of the fruit. In addition, the increased amount of sunlight can shorten the harvesting date.

Hereinafter, the present invention will be described with reference to the following examples for specific description of the present invention, but the present invention is not limited to the following examples.

Example 1

1) Preparation of breathable film

Untreated calcium carbonate (made by Omiya, calcium carbonate (A)) with an average particle diameter of 1.7 μm, and Samsung Total Chemical Co., Ltd. has a very wide weight average of the molecular weight distribution produced by extraction with boiling n-hexane. A fine pulverized product of an ethylene polymer (ethylene polymer (A)) having a molecular weight of 8,500 and a melt index (190 ° C., 2.16 Kg) of 95 g / 10 min was prepared as a sample. First, calcium carbonate (A) is added to the Henschel mixer, and ethylene-based polymer (A) is gradually added at a compounding ratio of 3 parts by weight of ethylene-based polymer (A) to 100 parts by weight of calcium carbonate (A). After stirring at high temperature for 30 minutes, a sample of calcium carbonate (A) having a structure partially coated with an ethylene polymer (A) was finally obtained.

Linear low density polyethylene (SK Co., Ltd., FT811, polyolefin resin (A) having a melt index (190 ° C., 2.16 Kg) of 2.7 g / 10 min and a density of 0.932 g / cm ³ based on 100 parts by weight of the inorganic filler (I) in the Henschel mixer. )) Polyolefin with 50 parts by weight and 50 parts by weight of commercially available isotactic polypropylene (isotactic pentad fraction by ¹³ C-NMR is 0.962, 135 ° C., intrinsic viscosity η 1.62 in tetralin solution) Resin (A) was added and mixed with 5 parts by weight of tris (nonylphenyl) phosphite as antioxidant and 5 parts by weight of 2,2,6,6-tetramethyl-4-piperidyl stearate as UV stabilizer. Then, it was injected into a twin screw extruder having a screw diameter of 130 mm and melt extruded to obtain a compound composition for breathable film in a pellet state. The obtained compound composition was put into a hopper and the disc sheet was shape | molded using the tee-die molding machine of a screw diameter of 130 mm. The molded disc sheet was uniaxially stretched 2.5 times at a stretching temperature of 70 ° C. to prepare a breathable film having a basis weight of 30 g / m 2.

2) Manufacture of agricultural laminated film

After spray-coating a solvent-free hot melt adhesive (DM-7035, manufactured by National Starch Co., Ltd.) at 280 ° C. on both sides of the manufactured breathable film, and spraying on a surface, one side of the mesh reinforcing film (warifu HS24, Nisseki Co., Japan) was bonded, and spunbond nonwoven fabric (Toray Saehan Co., Ltd. Jessbone (50 g / m 2) was bonded and rolled through a roller to integrate.

As a result, peeling was impossible, and as a result of measuring moisture permeability according to JIS Z0208, it was measured at 5732 gday / m 2 and showed excellent moisture permeability.

1 is a process chart for manufacturing the agricultural laminated film according to the present invention

<Description of Drawing Major Symbols>

10: breathable film 20a, 20b: hot melt adhesive

30a: mesh reinforcement film 30b: spunbond nonwoven fabric

40a, 40b: roller 50: winding roller

Claims (13)

A mesh reinforcing film layer prepared by cross-linking filaments made of polypropylene resin with each other and thermally pressing them together with a polyethylene film or by intersecting a filament having an inner layer made of a high density polyethylene resin and an outer layer made of a low density polyethylene resin; Solvent-free hot melt adhesive is melt-sprayed on top of the mesh reinforcing film layer hot melt adhesive layer laminated in the form of spots; Stacked on top of the hot melt adhesive layer, the weight average molecular weight of 5000 ~ 30,000 produced by boiling n-hexane to produce a high density polyethylene resin based on 100 parts by weight of inorganic filler, melt index (190 ℃, 2.16Kg) 50 100 parts by weight of an inorganic filler coated with an ethylene polymer obtained by mixing, rapidly stirring and dispersing 1 to 10 parts by weight of an ethylene polymer having a content of 100 g / 10 min and a polyolefin having a melt index (190 ° C., 2.16 Kg) of 1 to 10 g / 10 min. Breathable film layer using a compound composition for breathable film comprising 20 to 250 parts by weight of resin, 0.1 to 20 parts by weight of antioxidant, 0.1 to 20 parts by weight of UV stabilizer; A hot melt adhesive layer in which a solvent-free hot melt adhesive is melt-sprayed on the top of the breathable film layer and laminated in a spot shape; A spunbond nonwoven layer laminated on top of the hot melt adhesive layer; Strength laminated agricultural paper, characterized in that the laminated sequentially. The method of claim 1, The mesh reinforcement film has a basis weight of 15 ~ 40g / ㎡, thickness of 0.05 ~ 0.15mm, MD direction tensile strength of 90 ~ 230 N / 5cm, CD direction tensile strength of 90 ~ 230 N / 5cm Strengthened agricultural laminated film, characterized in that. delete delete The method of claim 1, The inorganic filler is calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, calcium chloride, calcium sulfate, aluminum hydroxide, zinc oxide, magnesium hydroxide, titanium oxide, alumina, mica, asbestos Strength reinforced agricultural laminated film, characterized in that at least one selected from the group consisting of, zeolite, clay silicate. The method of claim 1, The polyolefin resin is a group consisting of homopolymers or copolymers based on ethylene, polypropylene homopolymers or copolymers based on low density polyethylene, linear low density polyethylene, medium density polyethylene, and high density polyethylene, and polybutene Strength-enhanced agricultural laminated film, characterized in that at least one compound selected from. The method of claim 1, Said breathable film layer is obtained by stretching the original sheet melt-molded compound composition for breathable film in the range of 1.5 times to 36 times area stretch ratio, the strength reinforced agricultural paper. The method of claim 1, The solvent-free hot melt adhesive is characterized in that any one or more polyolefin resin selected from polyethylene, polypropylene, polybutylene, ethylene-propylene copolymer, propylene-butylene copolymer, ethylene-propylene-butylene terpolymer Agricultural laminated film reinforced with strength. The method of claim 8, The solvent-free hot melt adhesive is 50 to 55% by weight of at least one polyolefin resin selected from polyethylene, polypropylene, polybutylene, ethylene-propylene copolymer, propylene-butylene copolymer, ethylene-propylene-butylene terpolymer 40 to 45% by weight of at least one adhesive enhancer selected from petroleum resins, terpene resins, and rosin resins, and 5 to 10% by weight of at least one softening oil selected from aromatic oils, naphthenic oils, and paraffinic oils. Strengthened agricultural laminated film, characterized in that it comprises a. The method of claim 1, The spunbond nonwoven fabric is a strength-reinforced agricultural paper, characterized in that the nonwoven fabric by a spunbond method using any one resin selected from polyester, nylon, polyethylene, polypropylene. The method of claim 10, The spunbond nonwoven fabric has a thickness of 0.1 to 1 mm, tensile strength of 5 ~ 30 kg / 5cm, elongation is reinforced agricultural laminated film, characterized in that 60 to 100%. A) It is in a pellet state, and the weight average molecular weight of 5000 ~ 30,000 produced by boiling n-hexane when producing high density polyethylene resin with respect to 100 parts by weight of inorganic filler, melt index (190 ℃, 2.16Kg) 50 ~ 100g / 10min 100 parts by weight of an inorganic filler coated with an ethylene polymer obtained by mixing, stirring and dispersing 1 to 10 parts by weight of an ethylene polymer and a melt index (190 ° C, 2.16 Kg) of polyolefin resin 20 to 250 in a range of 1 to 10 g / 10 min. The original sheet obtained through melt extrusion of a compound composition for breathable films comprising 0.1 parts by weight, 0.1 to 20 parts by weight of an antioxidant and 0.1 to 20 parts by weight of a UV stabilizer in an extruder, has a glass transition point or more and a melting point or less. Drawing a breathable film by stretching at least 1.5 times to 36 times the area draw ratio under temperature; B) spray-melting a solvent-free hot melt adhesive on one surface of the stretched breathable film; C) adhering the mesh reinforcement film to the surface on which the hot melt adhesive is applied in the breathable film; d) rolling using a roller; e) spray-melting a solvent-free hot melt adhesive on the opposite side to which the mesh reinforcing film is bonded in the breathable film; f) adhering the spunbond nonwoven fabric to the surface to which the hot melt adhesive is applied; g) rolling using a roller; Method of producing a laminated film for agriculture reinforced with strength, characterized in that it has a. The method of claim 12, After the step f) using the embossing roller to form an embossing roller further comprising the method of manufacturing a strengthened agricultural laminated film characterized in that it further comprises.

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