JP4902303B2 - Paper agricultural covering - Google Patents

Description

  The present invention relates to a paper agricultural covering material, and in particular, to a paper agricultural covering material using paper as an aggregate, having a function necessary for growing crops and having a strength capable of being expanded by a machine. It is.

  As agricultural materials, covering materials form a big market. By blocking the light, weeding the weeds, adjusting the soil temperature, maintaining soil moisture, preventing soil erosion, preventing fertilizer runoff, controlling the occurrence of pests, The purpose is to help the crops grow.

  At present, polyolefin films such as polyethylene films are the mainstream, and films colored according to applications such as transparent, black, and green are widely used. Polyolefin-based films have advantages such as low cost, light weight, and little deterioration during storage. In addition, there are few problems regarding the growth of crops, and they have become indispensable materials for farmers.

  However, the greatest drawback of polyolefin films such as polyethylene films is that they are not decomposed in the soil. In other words, after use, it is necessary to wind up and collect it with a machine or by hand, and the burden of this collection work is large both physically and financially.

  Moreover, in these collection | recovery operations, a piece will inevitably remain in the soil, and these will remain permanently on the farmland. The incineration disposal that has been permitted so far as the treatment of the coating material after collection has also been prohibited due to the field revision, and the collected used film must be properly processed. This is also a problem at the disposal site, and the cost of disposal is a major problem that directly hits the farmer's management.

  In order to solve this problem, a method of dropping and reusing the soil has been proposed. However, in order to remove the soil completely and to spread this coating material with a machine, the next fiscal year must be taken up properly. There is a big problem that it cannot be used, and the fact is that the reuse is not progressing.

  As a method for solving this problem, development of a coating material using a biodegradable polymer is underway. Actually, many bio-degradable polymer coatings such as starch and polylactic acid have been put on the market. Especially in corn cultivation, which must be collected in the summer, these can be put into the soil as they are. Some of the products have started to be used.

  However, biodegradable polymer coating materials have not yet penetrated the market due to the high price. In the case of biodegradable polymers, degradation progresses during the storage period, and thus has a major problem that it cannot be stocked for distribution, and it must be said that there are still significant hurdles for this practical application. There is no situation.

  Similarly, a lot of paper coating materials are being developed as materials that can be easily decomposed in soil. In particular, in the case of paper, since it does not deteriorate with time even while being stored in a warehouse for distribution, its value as a product is much more advantageous than biodegradable polymers. In fact, paper-based agricultural coatings have already been put into practical use at various agricultural test sites (paper agricultural coatings are commonly referred to as paper multi-sheet or mulching paper) There).

  However, the biggest disadvantage of paper is that it is rapidly deteriorated by sunlight, ultraviolet rays, heat, rain, and wind, and it is severely collapsed in contact with the soil. There is to be. In addition, if there is a defect, it will be easily torn, which makes it difficult to expand with a machine.

In order to solve this problem, a method of adding an antifungal agent and / or an antibacterial agent to the portion in contact with the soil (see Patent Document 1), or flute processing or embossing to reduce the contact area with the soil and decompose The trial which delays (refer patent document 2) etc. is examined. In addition, a proposal has been made to delay decomposition / deterioration of a covering material during the cultivation of agricultural crops by adding a dry oil having a high water resistance / water repellency effect and relatively easy handling to the paper covering material (Patent Document 3). reference).
JP-A-9-205901 Japanese Patent Laid-Open No. 10-94335 JP 2000-116249 A

  However, conventional paper agricultural covering materials have problems in terms of cost, safety, and strength. For example, according to Patent Document 1 and Patent Document 2, both lead to an increase in cost, and the strength corresponding to the cost cannot be obtained. Further, according to Patent Document 3, even if the cost is cleared, it still remains. Since the strength cannot be obtained, it has not been put into practical use.

  Accordingly, an object of the present invention is to provide a paper agricultural covering material that does not impair the function as an agricultural covering material, has high safety, and has a strength capable of machine stretching.

  In order to achieve the above object, the present invention includes a drying oil, a semi-drying oil, a wax that is solid at room temperature and has a melting point of less than 100 ° C., and the blending ratio (mass ratio) thereof is drying oil: semi-drying oil: wax = Provided is a paper agricultural covering material comprising an oil or fat composition of 1.0: 1.0 or less: 0.3 or less contained in part or all of paper that can be decomposed in soil.

  Further, in order to achieve the above object, the present invention provides a dry oil, a semi-dry oil and a wax having a melting point of less than 100 ° C. at a part or all of a part of the paper that can be decomposed in soil. Is provided, and the content ratio by mass of the dry oil: semi-dry oil: wax = 1.0: 1.0 or less: 0.3 or less is provided.

  According to the present invention, it is possible to provide a paper agricultural covering material having a high safety and strength capable of machine stretching without impairing the function as an agricultural covering material.

[Paper Agricultural Coating Material According to Embodiment of the Present Invention]
The paper agricultural coating material according to the embodiment of the present invention includes a drying oil, a semi-drying oil, a wax that is solid at room temperature and has a melting point of less than 100 ° C. Oil: wax = 1.0: 1.0 or less: 0.3 or less An oil composition is contained in a part or the whole of paper that can be decomposed in soil. Oil composition containing a drying oil and a semi-drying oil with a compounding ratio (mass ratio) of drying oil: semi-drying oil = 1.0: 1.0 or less is contained in part or all of paper that can be decomposed in soil. Then, the wax may be contained in the oil composition-containing portion of the paper so that the mass ratio with the drying oil is 1.0: 0.3 or less.

  As a result, a part of the paper that can be decomposed in the soil or an arbitrary part of the whole contains a drying oil, a semi-drying oil, and a wax that is solid at room temperature and has a melting point of less than 100 ° C. : Semi-drying oil: wax = 1.0: 1.0 or less: 0.3 or less can be obtained.

(Paper agricultural covering material)
The paper agricultural covering material in the present invention means an agricultural covering material made of paper that can be decomposed in soil. The agricultural covering material in the present invention means a material capable of covering the soil surface of a portion other than the agricultural product in the cultivation of the agricultural product. Agricultural covering material covers the surface of soil other than crops, and has effects such as suppression of weed growth, adjustment of soil temperature, retention of soil moisture, prevention of soil erosion, prevention of fertilizer runoff, and prevention of pests. Therefore, it is used to help grow crops. Moreover, the agricultural coating | covering material in this invention may be called a multi sheet | seat or a mulching.

(Drying oil)
The dry oil refers to those classified as those subject to oxidative polymerization when vegetable oil is used for paints and inks. Definitions are those with an iodine number of 130 or more, and generally include linseed oil, safflower oil, soybean oil, tung oil, grape seed oil, walnut oil, evening primrose oil, coconut oil, hemp seed oil, etc. Examples of this include urushi kernel oil, pomegranate seed oil, tobacco seed oil, and the like. These drying oils can use 1 type (s) or 2 or more types.

(Semi-drying oil)
Semi-drying oil is also the same in the paint field as it does not form a film by oxidation polymerization as easily as drying oil, but it is clearly separated from non-drying oil that usually does not dry at all as polymerization progresses with time. is there. Definitions are those with an iodine value of 100 or more and less than 130, such as sesame oil, cottonseed oil, corn oil, rapeseed oil, rice oil, almond oil, and academically apricot kernel oil, orange seed oil, etc. To do. These semi-drying oils can be used alone or in combination of two or more.

(wax)
The wax is solid at normal temperature and does not have a clear definition. However, in the present embodiment, an organic compound that is solid at normal temperature (about 20 to 35 ° C.) and has a melting point of less than 100 ° C. is defined as wax. Define. Applicable examples include candelilla wax, carnauba wax, rice wax, jojoba oil, wood wax, lanolin, bees wax, montan wax, ceresin, paraffin wax, microcrystalline wax, and hardened castor oil. These waxes can be used alone or in combination of two or more.

(Combination of oil and fat composition)
A combination of drying oil, semi-drying oil and wax is not particularly limited, and there are many combinations. Since these products use natural products as starting materials, prices vary greatly depending on the situation, so it is desirable to change them according to the situation at that time. Among these, from the viewpoint of suitability during the drying operation, it is preferable that the drying oil is a combination of linseed oil, the semi-drying oil is rapeseed oil, and the wax is a paraffin wax.

(Fraction composition of oil and fat composition)
In order to maintain the strength at which mechanical stretching is possible, the blending ratio of the drying oil, semi-drying oil and wax in the oil and fat composition contained in the paper is important. That is, the blending ratio (mass ratio) is set to dry oil: semi-dry oil: wax = 1.0: 1.0 or less: 0.3 or less. Exceeding the upper limit of the semi-drying oil and wax causes problems such as cracking in the drying process. Dry oil: Semi-dry oil: Wax = 1.0: 1.0 or less: More preferably 0.2 or less, and still more preferably, Dry oil: Semi-dry oil: Wax = 1.0: 0.9 or less : 0.15 or less.

  Although a lower limit is not limited, It is preferable that the compounding ratio (mass ratio) is drying oil: semi-drying oil: wax = 1.0: 0.6 or more: 0.03 or more. Since the strength of mechanical stretching decreases as the blending ratio of semi-drying oil and wax approaches 0, it is preferable to set the lower limit value suitable for practical use as described above. There are some differences depending on the application status (content) on paper. Drying oil: Semi-drying oil: Wax = 1.0: 0.6 or more: More preferably 0.05 or more, more preferably drying oil: Semi-drying oil: Wax = 1.0: 0.7 or more : 0.07 or more.

  From the above, it is preferable that the semi-drying oil is 60 to 100 parts by mass and the wax is 3 to 30 parts by mass (mass ratio) with respect to 100 parts by mass of the drying oil. In addition, some pigments may be used for coloring the paper.

(Content of oil and fat composition in paper agricultural covering material)
The content of the oil / fat composition in the paper agricultural covering material is not particularly limited, but is preferably 2 to 20% by mass with respect to the dry mass of the paper, and 2 to 10% by mass. Is more preferable, and 4 to 8% by mass is particularly preferable. When the content of the oil / fat composition in the paper agricultural coating material is within the above range, the coating material can maintain its function as a coating material without being decomposed or degraded during the cultivation of agricultural products. The workability of the stretching is also good. If it is thickly coated, the strength is improved, but the mass of the base paper itself is increased, so that workability may be deteriorated.

  Here, “containing” is not limited to the case of coating on the surface of paper. That is, impregnation, application (coating), spraying, printing, etc. are mentioned as a method of making a paper agricultural covering material contain an oil and fat composition. Industrially, it is preferable to employ a step of drying after printing or impregnation.

  The oil / fat composition is contained in a part or the whole of the paper. A part refers to an end part buried in the soil or a part in contact with the soil.

(paper)
Usable paper is paper made of so-called wood pulp (paper mainly made of cellulose), and is paper that can be decomposed in soil. That is, it is possible to use wood pulp as a raw material, which is dispersed in water, dehydrated and dried, and entangled with fibers. Examples include kraft paper, newspaper, coated paper, high-quality paper, Kent paper, Japanese paper, kenaf paper, and the like. Waste paper pulp may be used. Non-woven fabrics and the like that are pressure-bonded with a synthetic resin-based adhesive that is not decomposed in soil are not desirable because they are not decomposed in farmland.

[Effect of the embodiment of the present invention]
According to the embodiment of the present invention, the following effects can be obtained.
(1) Since it is difficult to be decomposed and deteriorated during the cultivation of agricultural products, the function as a covering material can be maintained during the cultivation of the agricultural products (for example, 1 month to 3 months).
(2) After the crop is harvested, it will be decomposed if buried in the soil, so there is no need for post-harvest collection and disposal of the crop, reducing the burden of collection work.
(3) A paper agricultural covering material having extensibility and strength capable of being mechanically stretched can be provided. By adjusting the ratio of drying oil, semi-drying oil, and wax, the strength of mechanical extension can be adjusted, and the strength can be maintained for a certain period even in contact with the soil during use. Can withstand the use of
(4) Since a drying oil, a semi-drying oil and a wax are contained on a paper base, a biodegradable coating material can be provided at a relatively low cost.
(5) Uses highly safe drying oil, semi-drying oil, and wax, and applies them to the surface of paper to delay decomposition due to contact with the soil and to prevent raindrops from collapsing by rain. Can also be obtained.
(6) It is possible to provide an agricultural covering material that can be easily stocked for distribution.

(Examples 1-4)
The paper-made agricultural coating | covering materials of Examples 1-4 which contained the oil-fat composition of the mixing | blending shown in Table 1 were manufactured as follows.

  The oil and fat composition (coating oil) having the composition shown in Table 1 was prepared in a tank, heated and dissolved above the melting point of each wax, and then mixed well until uniform. The blending ratio of the drying oil, the semi-drying oil and the wax was 80 parts by mass of the semi-drying oil and 10 parts by mass of the wax with respect to 100 parts by mass of the drying oil.

  This oil and fat composition was impregnated on both sides of kraft paper and then dried. In Examples 1-4, the oil and fat composition was 5.0% by mass (Example 1), 6.5% by mass (Example 2), 4.8% by mass (Example 3), and 5% with respect to the base paper. 6 mass% (Example 4) was included.

(Comparative Example 1)
The paper agricultural covering material of Comparative Example 1 containing the oil and fat composition having the composition shown in Table 1 was produced as follows.

In Comparative Example 1, a mixture of non-drying oil candy oil and carnauba wax was impregnated on both sides of kraft paper and then dried. The blending ratio of cocoon oil and carnauba wax was 180 parts by mass of cocoon oil and 10 parts by mass of carnauba wax. The fat and oil composition was included in the base paper in an amount of 58.7% by mass.

  However, the paper agricultural covering material of Comparative Example 1 did not dry at all in the subsequent processing steps, and the oil oozed from the surface of the paper and wound up as it was, so that the oil adhered. This could not be rolled up for a spreading machine and was not very durable.

  In Table 1, safflower oil (manufactured by Nissin Oilio Group, trade name: Nisshinbeni Flower Oil), flaxseed oil (manufactured by Nisshin Oilio Group, trade name: N / B flaxseed oil), soybean oil (Nisshin Oil Product name: Soybean White Oil (S)), Tung Oil (Cosmo Oil Chemical Co., Ltd., Product Name: Tung Oil), Cottonseed Oil (Nisshin Oilio Group, Product Name: Nisshin Salad Oil) Cream cottonseed), rapeseed oil (manufactured by Nisshin Oil Rio Group, trade name: rapeseed white squeezed oil (S)), corn oil (manufactured by Nisshin Oillio Group, trade name: Nisshin Corn Oil), rice oil ( Nisshin Oilio Group Co., Ltd., trade name: Nisshin Kome white squeezed oil) and cocoon oil (trade name: Sakai tempura oil) were used.

(Examples 5-6, Comparative Examples 2-3)
Next, in the combinations of Example 2 in Table 1 (drying oil: linseed oil, semi-drying oil: rapeseed oil, wax: paraffin wax), the blending ratio was changed as shown in Table 2, and Examples 5 to 6 were changed. And the paper agricultural coating | covering material of Comparative Examples 2-3 was manufactured like the said Example and comparative example.

  Comparative Example 2 is an example in which the mixing ratio of semi-drying oil and wax is insufficient (here, an example of non-use), and is a paper agricultural covering material impregnated with only drying oil. Moreover, the comparative example 3 is an example with too many semi-drying oil and wax compounding ratios.

(Strength evaluation)
Table 3 shows the results of analyzing the strength of the paper-made agricultural covering materials produced in the above Examples and Comparative Examples in accordance with Japanese Industrial Standard: Japan Industrial Standard (JIS method). The strength was measured for tensile strength (longitudinal) (JIS P8113), wet tensile strength (longitudinal) (JIS P8135), tear strength (longitudinal) (JIS P8116), and burst strength (JIS P8112).

  In addition, although the same paper is used for all the base papers, since the amount of the oil and fat composition contained is different, each strength is a value converted by basis weight (mass per unit area). Each strength is represented by a numerical value corresponding to 100 as the raw data value of the raw paper.

As a result, as shown in Table 3, the paper agricultural covering materials of the Examples all have wet tensile strengths that are important as indicators of durability against rain and wind during outdoor cultivation, exceeding the base paper. Some paper agricultural coverings were more than doubled. In addition, with respect to other strengths, the paper agricultural covering material of the example was stronger than the strength of the base paper or approximately the same as the strength of the base paper, and was strong enough to be used as an agricultural covering material.
From the above, it can be seen that the paper agricultural covering material of the example is extremely useful when cultivated in an outdoor environment.

  Compared to this, in Comparative Example 2 that does not use semi-drying oil and wax (insufficient blending ratio), as shown in Table 3, the tear strength is remarkably reduced, which is less than half that of the base paper. Only numerical values were obtained. If the tear strength is lowered, it cannot be stretched by a machine, and even if it is stretched, it presents a large defect that is easily torn due to the wind. Further, in Comparative Example 3 in which the mixing ratio of the semi-drying oil and the wax is too large, the tear strength is remarkably reduced, the film cannot be stretched by a machine, and the film formed on the surface seems to be wrinkled. Admitted.

(Field test)
In an actual radish field, using the coating material produced in Example 2 (Example 6), a spreading test, a cultivation test from sowing to harvesting, and a decomposition test in soil were performed.

  In the radish field, the coating material of Example 2 (Example 6) was stretched by Malchar, but it was possible to stretch without breaking even in 100m stretching.

  In addition, the radish was cultivated for 60 days from sowing to harvesting using the coating material of Example 2 (Example 6). As shown in FIG. 1 (photo), weed growth was suppressed without problems until harvesting. However, the coating material can be used without being damaged.

  Furthermore, after harvesting the radish in autumn, the covering material of Example 2 (Example 6) was buried in the soil. The covering material was decomposed and disappeared cleanly in the spring.

It is a photograph showing the result of a field test.

Claims (8)

  Including dry oil, semi-dry oil, wax that is solid at room temperature and has a melting point of less than 100 ° C., and its blending ratio (mass ratio) is dry oil: semi-dry oil: wax = 1.0: 1.0 or less: 0.3 A paper agricultural covering material comprising the following oil-and-fat composition in part or all of paper that can be decomposed in soil.   A part of or all of the paper that can be decomposed in the soil contains a drying oil, a semi-drying oil, and a wax that is solid at room temperature and has a melting point of less than 100 ° C. Oil: wax = 1.0: 1.0 or less: 0.3 or less, a paper agricultural covering material.   3. The paper according to claim 1, wherein the blending ratio or the content ratio is dry oil: semi-dry oil: wax = 1.0: 0.6 or more: 0.03 or more. Agricultural covering material.   The drying oil is one or more selected from the group consisting of linseed oil, safflower oil, soybean oil, tung oil, grape seed oil, walnut oil, evening primrose oil, coconut oil and hemp seed oil The paper agricultural covering material according to any one of claims 1 to 3.   The said semi-drying oil is 1 type, or 2 or more types chosen from the group which consists of sesame oil, cottonseed oil, corn oil, rapeseed oil, rice oil, and almond oil, The any one of Claim 1 thru | or 4 characterized by the above-mentioned. The paper agricultural covering material as described in the item.   The wax is one or two selected from the group consisting of candelilla wax, carnauba wax, rice wax, jojoba oil, wood wax, lanolin, bees wax, montan wax, ceresin, paraffin wax, microcrystalline wax, and hardened castor oil. The paper agricultural covering material according to any one of claims 1 to 5, wherein the covering material is a seed or more.   The paper farming according to any one of claims 1 and 3 to 6, wherein the paper contains 2 to 20% by mass of the oil and fat composition with respect to the dry mass of the paper. Coating material.   The paper agricultural coating according to claim 2, wherein the paper contains the drying oil, the semi-drying oil, and the wax in a total amount of 2 to 20% by mass with respect to the dry mass of the paper. Wood.