JP2001061339A - Cover for field crop - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a field crop cover which can hold water evaporated from the field crops to prevent the deterioration of the qualities of the field crops by the dropping of dew condensation water on the field crops and has a waterproof property, a shading property and an air-permeability to maintain the qualities of the field crops, in a state that the field crops are collected. SOLUTION: This cover for covering field crops in response to the shape of their collected product is obtained by joining a water-holding waterproof sheet 2 for covering a ceiling portion to a shading and air-permeable sheet 3 for covering at least one portion of the side portions. The water-holding waterproof sheet 2 is the laminate of a water-holding layer to a waterproof layer. The water-holding layer is obtained by sticking an acrylic resin to a polyester fiber nonwoven fabric. The waterproof layer comprises a polyolefin laminate cloth.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to waterproofness, water retention,
The present invention relates to a crop cover having light-shielding properties and breathability.

[0002]

2. Description of the Related Art Conventionally, crops such as potatoes and onions are collected in a collection container when they are harvested. However, they are not immediately processed but are transported to a processing plant or marketed after several days while being packed in the collection container. Often shipped. During that time, the collection container is left outdoors and stored in a field or the like, and is often covered with a cover made of a waterproof sheet in order to prevent rain and dew and to shield light. However, during this storage, the waterproof and light-shielding properties are sufficient, but the air permeability is not sufficient, so that a large amount of moisture emanates from potatoes, onions, etc., and dew condensation occurs on the back of the cover due to temperature differences between day and night. In addition, there is a problem that generated water droplets again drop on potatoes, onions and the like, which significantly lowers the quality of agricultural products.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and, in the state of collecting agricultural products, retains water emanating from the agricultural products to prevent dew condensation water from dropping onto the agricultural products and reduce the quality. It is an object of the present invention to provide a crop cover having a waterproof property, a light-shielding property, and an air permeability, and maintaining the quality of the crop.

[0004]

According to the present invention, there is provided, as a means for solving the above-mentioned problems, a cover for covering agricultural products according to the shape of the aggregate thereof, and a water-retentive waterproof sheet for covering a ceiling portion. A light-shielding and breathable sheet that covers at least a part of the side surface is joined, and the water-retaining waterproof sheet is
An object of the present invention is to provide a cover for agricultural products, which is a laminate of a water retention layer in which an acrylic resin is adhered to a nonwoven fabric made of polyester fiber and a waterproof layer made of a polyolefin laminate cloth.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the drawings. FIG. 1 is a perspective view schematically showing a crop cover 1 according to the present invention. Reference numeral 2 denotes a water-retentive waterproof sheet, reference numeral 3 denotes a light-shielding breathable sheet, and reference numeral 4 denotes an eyelet provided for binding a cover.

FIG. 3 shows a container 7 for collecting agricultural crops, which is an example of an object to be covered. FIG. 3 is an explanatory view showing a state where five potatoes 8 are housed in a rectangular container 7 for collecting crops. The object to be covered forms a ceiling part 5 and a side part 6, and when the collection container 7 is covered with the crop cover 1, the ceiling part 5 needs to be covered with the water-retentive waterproof sheet 2. It is necessary that at least a part of the sheet covering the side surface part 6 is the light-shielding and breathable sheet 3.

FIG. 4 shows a state in which the agricultural product cover 1 covers an object in which five collection containers 7 are arranged. The ceiling portion 5 is covered with the water-retentive waterproof sheet 2, and the four side surfaces 6 around the light-shielding and breathable sheet 3 hang down from the ceiling portion 5 to cover the target object. The string is attached to the lower part of the collection container 7 through the eyelets 4 provided at the lower end of the periphery of the crop cover 1 around the four sides thereof, and is fixed.

[0008] However, the agricultural crop cover 1 of the present invention.
The cover covers the crop in accordance with the shape of the aggregate, and is not limited to the above shape, and a cover having a shape corresponding to an arbitrary shape is used. Therefore, the cover may be in the form of a single sheet, or as shown in FIG. 2, may be cut out so as to be easily formed into a rectangular parallelepiped box shape, and further conformed to the rectangular parallelepiped shape by means such as sewing. The present invention is also included in a box-shaped structure.

The water-retentive waterproof sheet 2 may cover not only the ceiling 5 of the object but also a part of the four side surfaces 6 around the object. Further, the light-shielding and permeable sheet 3 is configured to cover at least a part of the side surface portion 6 of the object, preferably 50% or more of the total area of the side surface portion 6,
More preferably, it accounts for 75% or more. The light-shielding and breathable sheet 3 may cover the entire four side faces 6 as in the present embodiment, but may cover three or two of the four sides, or each side part. A configuration may be adopted in which windows are randomly provided so that the total of the light-shielding and permeable sheets 3 of No. 6 is at least 50% or more. If the proportion of the light-shielding and air-permeable sheet 3 is less than 50%, the air permeability will be insufficient, which is not preferable.

Water-repellent waterproof sheet 2 and light-shielding breathable sheet 3
As a method for joining the two, any of sewing, welding, and bonding using an adhesive can be used.

The water-retentive waterproof sheet 2 is a laminate of a water-retentive layer 10 in which an acrylic resin is adhered to a nonwoven fabric made of polyester fiber, and a waterproof layer 11 made of a polyolefin laminate cloth.

The polyester fiber non-woven fabric constituting the water retaining layer 10 is obtained by entanglement bonding short fibers having a fineness of 0.1 to 10 denier formed with polyester by a known needle punching method, a spunlace method or the like. And a nonwoven fabric made of polyester filaments by a melt blow method, a spun bond method, or the like.
The polyester used is not particularly limited, but preferably has a high melting point such as a homopolyester such as polyethylene terephthalate, and contains a copolymer component as long as the effects of the present invention are not impaired. There may be. The nonwoven fabric preferably has a polyester fiber content of 50% by weight or more, preferably 70% by weight.
The above is more preferable. If the content of the polyester fiber is less than 50% by weight, the nonwoven fabric is crushed by heat at the time of joining by a sandwich lamination method with a waterproof layer described later, and the water retention amount is not preferable.

The acrylic resin is a homopolymer or a copolymer of an alkyl (meth) acrylate, and an α, β-ethylenically unsaturated monomer containing at least one of these and a crosslinkable functional group. And a modified (meth) acrylic acid alkyl ester copolymer obtained by copolymerizing the above.

Specific examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, normal butyl (meth) acrylate, and normal (meth) acrylate. And isopropyl ester.

The α, β-ethylenically unsaturated monomer containing a crosslinkable functional group is specifically, an α, β-unsaturated dicarboxylic acid such as maleic acid, fumaric acid, itaconic acid or the like. Examples thereof include anhydrides or carboxylic acid group-containing monomers such as unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and vinyl acetic acid. Those containing a hydrophilic group such as a carboxyl group are preferable in terms of improving water retention.

As a method for attaching the acrylic resin to the polyester fiber nonwoven fabric, a solvent solution or emulsion of the acrylic resin is attached by a known method such as a dipping method, a roll coating method, a brushing method, a spray method, or the like. Can be. Among the above methods, the roll coating method is preferable because it is easy to handle and uniform adhesion can be achieved.

The amount of the acrylic resin (in terms of solid content) is 5 to 30% by weight with respect to the polyester fiber non-woven fabric.
Preferably, it adheres, more preferably 10 to 20% by weight. If the amount is less than 5% by weight, the water retention effect is inferior. If the amount exceeds 30% by weight, the flexibility is undesirably reduced.

The polyolefin laminate cloth constituting the waterproof layer 11 has a structure in which a polyolefin layer 14 is provided on both sides or one side of a woven fabric 13 formed by weaving drawn yarns made of polyolefin. As the polyolefin used for the drawn yarn, high-density polyethylene or polypropylene having a drawing effect is preferably used. As the fiber form, any of a monofilament, a multifilament, a flat yarn, a split yarn and the like can be used. Among them, a flat yarn which is flexible and has excellent moldability is preferable.

As a method for providing the polyolefin layer 14 on both sides or one side of the woven fabric 13, a known extrusion laminating method is used. Examples of the polyolefin used for the polyolefin layer 14 include low-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-alkyl acrylate copolymer,
Polyolefins commonly used in laminating methods, such as propylene-ethylene copolymers, can be used.

The water-retentive waterproof sheet 2 of the present invention is formed by laminating the water-retentive layer 10 and the waterproof layer 11.
The laminating method includes a pre-formed water retaining layer 10 and a waterproof layer 1.
1 may be laminated using an adhesive or the like,
It is preferable to provide a sandwich laminate layer 12 and a laminate between the waterproof layer 11 and the known sandwich laminate method. (See Fig. 5)

The light-shielding and air-permeable sheet 3 is a sheet having light-shielding properties and air-permeability, and is made of a plain weave or a weft using a drawn yarn made of a thermoplastic resin such as nylon, polyester, polyvinyl chloride or polyolefin. A mesh sheet woven by leno weave or the like is preferred.
Various forms such as flat yarn, split yarn, and monofilament can be adopted as the form of the drawn yarn. The weaving density of the mesh sheet is not particularly limited, but is preferably a dense tissue having light-shielding properties and having fine gaps having appropriate air permeability. It is preferable to improve the light shielding property by blending a coloring pigment such as carbon black into the drawn yarn. The light-shielding rate of the light-shielding and breathable sheet 3 is preferably from 50 to 97%, more preferably from 60 to 95%. Shading rate is 50
%, The light-shielding effect is reduced and discoloration of agricultural products is caused, which is not preferable. If the light-shielding ratio is more than 97%, air permeability is reduced, which is not preferable.

The thermoplastic resin used in the present invention includes an antioxidant, a lubricant, an ultraviolet absorber, a light stabilizer, a flame retardant, an antistatic agent, a pigment within a range not departing from the gist of the present invention depending on the purpose of use. Further, additives such as an inorganic filler, an organic filler, a crosslinking agent, a foaming agent, and a nucleating agent may be blended.

[0023]

EXAMPLE 1 Polyester staple fiber (melting point = 25)
4 ° C) using a spunlace molding machine with a basis weight of 10
A spunlace nonwoven fabric of 0 g / m ² was formed. An aqueous emulsion of acrylic acid ethyl ester (solid content = 45% by weight) was attached to the nonwoven fabric using a gravure coater and dried to form a water retention layer 10 having a finish weight of 110 g / m ² .

On the other hand, high density polyethylene (MFR = 2 g)
/ 10 min, density = 0.958 g / cm ³ ) to form a flat yarn having a single yarn fineness of 1000 d, and a flat woven fabric 13 was obtained with a driving density of 10 × 10 yarns / inch. On one side of the woven fabric 13, a low-density polyethylene (MFR = 12 g / 10 min, density = 0.
917 g / cm ³ ) to form a waterproof layer 11 having a thickness of 30 μm provided by an extrusion lamination method.

Next, the woven fabric 1 of the water retention layer 10 and the waterproof layer 11
The water-retentive waterproof sheet 2 was obtained as a laminate having a 50 μm sandwich laminate layer 12 provided between the three sides by the sandwich laminate method using the low-density polyethylene.

The water retention layer 10 was flattened and impregnated with water with a spoid, and the water content immediately before the formation of a water film on the surface was defined as the water retention volume. The water retention was 232 g / m ² , indicating good water retention.

In order to form the light-shielding and breathable sheet 3, a high-density polyethylene (MFR = 1.1 g / 10 mi)
n., a density of 0.951 g / cm ³ ) and a fineness of 300 d using a composition obtained by adding 0.3% by weight of carbon black.
And a flat yarn having a fineness of 1000 d were formed. Using this monofilament as a warp and a flat yarn as a weft, a light-shielding breathable sheet 3 which is a mesh sheet woven with a driving density of 8 × 14 yarns / inch in length and width was obtained. The light-shielding and breathable sheet 3 had a light-shielding ratio of 90% and a basis weight of 80 g / m ² .

Next, the water-retentive waterproofing sheet 2 was placed in a 2 × 6
m, and the light-shielding and breathable sheet 3 is placed around the four sides of the sheet.
The pieces were joined by a width of 5 m, adjusted to a rectangular shape of 5 × 9 m, all edges were turned around, and eyelets 4 were cast at intervals of 60 cm to obtain a crop cover 1.

The object to be covered is a potato 8 harvested in a field and, as shown in FIG. 3, is stored for about 1 ton in a collection container 7 of 1.7 × 1.1 m in length and 1.4 m in height. The collection containers 7 are arranged in a row and covered with the crop cover 1 obtained earlier, and as shown in FIG. 4, a string is passed through eyelets 4 provided around the four sides of the cover and tied to the lower portion of the collection container 7. Fixed. The water-retentive waterproof sheet 2 is the water-retentive layer 1
0 covered the ceiling part 5 of the collection container 7 such that the waterproof layer 11 was on the inside and the waterproof layer 11 was on the outside, and the light-shielding and breathable sheet 3 covered the side parts 6. The water escaping from the potato 8 stored in this manner for four days is absorbed by the water-retentive waterproof sheet 2 or eliminated due to ventilation of the cover side surface 6 due to ventilation, so that there is no dripping to the potato 8 due to condensation. In addition, there was no discoloration due to the effects of light shielding and ventilation, no stuffiness due to temperature rise, and no deterioration in potato 8 quality was observed.

Example 2: The nonwoven fabric used in Example 1 was adhered and dried using a gravure coater with an aqueous emulsion of acrylic acid ethyl ester (solid content: 45% by weight) to give a finish weight of 125 g / m2. ² water retention layer 10
Was carried out in the same manner as in Example 1 except that was formed. The water retention amount of the water retention layer 10 measured in the same manner as in Example 1 was 280 g / m ² , indicating good water retention, and thus could be suitably used as the agricultural crop cover 1.

Comparative Example 1 The procedure of Example 1 was repeated except that the acrylic resin was not attached to the nonwoven fabric made of polyester fiber. The amount of water retained was measured in the same manner as in Example 1. However, since the polyester fibers did not penetrate the water,
It was unsuitable as 0 and was not preferable as the crop cover 1.

Comparative Example 2: A basis weight 10 consisting of a cotton blend of 50% by weight rayon short fibers and 50% by weight polyethylene short fibers.
The procedure was performed in the same manner as in Example 1 except that the acrylic resin was not adhered to the nonwoven fabric of 0 g / m ² . Since the rayon short fibers were crushed during sandwich lamination, the water retention amount of the water retention layer 10 measured in the same manner as in Example 1 was 80 g / m.
² was poor in water retention, and was unsuitable as the crop cover 1.

[0033]

As described above, the cover for agricultural products of the present invention is provided with a waterproofing sheet for preventing rain and dew on agricultural products stored outdoors by a combination of a water-retaining waterproof sheet and a light-shielding air-permeable sheet. A light, high-strength cover for agricultural products that has water resistance, does not become stuffy due to temperature rise due to light-shielding effect and ventilation effect, and water radiating from agricultural products is retained in the water retention layer that constitutes the water-retaining waterproof sheet. Can be covered without deteriorating the quality of the potato, and is particularly suitably used as a potato cover.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a crop cover according to the present invention.

FIG. 2 is a perspective view schematically showing a modification of FIG.

FIG. 3 is an explanatory view showing a state in which five collection containers accommodating potatoes are arranged in the collection container.

FIG. 4 is an explanatory diagram showing a state in which the collection container of FIG. 3 is covered with the crop cover of the present invention and connected with a string.

FIG. 5 is a schematic sectional view of the water-retentive waterproof sheet of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Agricultural crop cover 2 Water-retentive waterproof sheet 3 Light-shielding air-permeable sheet 4 Eyelet 5 Ceiling 6 Side surface 7 Collection container 8 Potato 9 String 10 Water-retaining layer 11 Waterproof layer 12 Sandwich laminate layer 13 Woven cloth 14 Polyolefin layer

Claims (1)

[Claims] 1. A cover for covering agricultural products according to the shape of the aggregate thereof, comprising a water-retentive waterproof sheet covering a ceiling portion and a light-shielding breathable sheet covering at least a part of a side portion, The agricultural product cover, wherein the water-retentive waterproof sheet is a laminate of a water-retentive layer in which an acrylic resin is attached to a nonwoven fabric made of polyester fiber and a waterproof layer made of a polyolefin laminate cloth.