JP4242579B2 - Cover sheet for fumigation - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet used for fumigating trees such as conifers such as pine, wood, processed products such as pallets and cases, packaging materials, fruits, grains, soil, and the like.
[0002]
[Prior art]
In recent years, pine damage caused by pine worms such as the pinewood beetle has become a worldwide problem.
Therefore, various methods have been proposed as measures against pine worms. One of them is fumigation treatment using a fumigant.
Pines withered by pine worms are cut down and collected, and then fumigated for about two weeks. At this time, the gas discharged from the fumigant is covered with a fumigation sheet so as not to leak outside.
In addition, fruits and grains are put in boxes, bags, etc., and in a stacked state, they are covered with sheets and subjected to fumigation.
Furthermore, about a soil, a fumigant and soil are mixed and a sheet | seat is covered on it and a fumigation process is performed.
[0003]
[Problems to be solved by the invention]
The fumigation process is often performed in the mountains, and the work of collecting and cleaning the fumigation sheet requires a great deal of labor and expense. For handling sheets that may have a fumigant attached. Needed great care.
Therefore, a sheet using a biodegradable resin that can be decomposed only by being buried in soil has been attracting attention. However, the weather resistance is not sufficient, and there has been a problem that the fumigant leaks due to the deterioration of the sheet and the fumigated material gets wet in the rain.
[0004]
[Means for Solving the Problems]
The present invention has been made to solve the above problems, and the invention according to claim 1 is characterized in that the ultraviolet absorbent is 0.05 to 5 parts by weight with respect to 100 parts by weight of the biodegradable aliphatic polyester resin. A sheet formed from a resin composition formed by adding 0.1 to 10 parts by weight of an inorganic filler and 0.01 to 3 parts by weight of a light stabilizer, and used when fumigating a fumigated material A fumigation coating sheet,
The invention described in claim 2 is a fumigation coated sheet having a thickness of 0.05 to 0.3 mm in addition to the structure described in claim 1 .
[0006]
Biodegradable aliphatic polyesters are one or more of glycol components such as ethylene glycol, 1,4-butanediol and hexanediol, and one of aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid and sebacic acid. Polyesters comprising more than one species; Lactone polymers such as poly (ε-caprolactone) and poly (β-propiolactone); 3-hydroxybutyrate, 3-hydroxypropionate, 4-hydroxybutyrate, 3-hydroxy A homopolymer or copolymer of a hydroxyalkanoate such as valerate, 3-hydroxyoctanoate, 5-hydroxyvalerate and the like . These aliphatic polyesters can be used alone or in combination.
[0007]
Examples of the ultraviolet absorber used in the present invention include salicylic acid esters, benzotriazoles, hydroxybenzophenones, acrylonitrile substitution products, and the like. These ultraviolet absorbers can be used alone or in admixture of two or more. Specifically, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-ethoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5,5′-methylenebis (2-hydroxy 2-hydroxybenzophenones such as -4-methoxybenzophenone); 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butyl) Phenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-tert-) Octylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-dicumylphenyl) 2- (2′-hydroxyphenyl) benzotriazoles such as nzotriazole, 2,2′-methylenebis (4-tert-octyl-6-benzotriazole) phenol; phenyl salicylate, resorcinol monobenzoate, 2,4 Benzoates such as di-tert-butylphenyl-3 ′, 5′-di-tert-butyl-4′-hydroxybenzoate, hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate; 2-ethoxy Oxanilides such as -4'-dodecyl oxanilide; cyanoacrylates such as ethyl-α-cyano-β, β-diphenyl acrylate, methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate Is mentioned.
These ultraviolet absorbers may be used alone or in combination of two or more.
[0008]
The fumigation covering sheet covers the fumigated material outdoors, and depending on the type of fumigated material, it needs to be covered with the fumigation covering sheet for almost one year. At that time, it is necessary to fix the sheet by placing a weight on the edge of the sheet so that the fumigation covering sheet is not blown off by wind or the like, or the fumigant gas does not leak out.
Moreover, although the addition amount of a ultraviolet absorber is 0.05-5 weight part with respect to 100 weight part of biodegradable aliphatic polyester resin mentioned above, since the coating sheet for fumigation is used outdoors, it is ultraviolet rays. When the amount of the absorbent added is small, the deterioration of the sheet is promoted. In particular, biodegradation is likely to occur in the portion of the sheet that is in contact with the ground or buried in the soil. When the sheet is deteriorated by ultraviolet rays, the sheet deteriorates, the sheet strength is weakened and the sheet is broken by wind or the like, or the deteriorated portion is likely to be biodegraded, and the fumigation sheet has a hole or the like. Arise. In particular, when used for soil fumigation, the problem of UV degradation is serious, and if the fumigation sheet is perforated or if the sheet becomes thin and the gas permeability increases, the gas generated from the fumigant will increase. Not only will it leak out and the fumigation process will not be sufficient, but it will also sprinkle toxic gas around it. In addition, there is a problem that rain enters from the hole in the sheet and the material to be fumigated gets wet. Furthermore, in the case of pine, before the fumigant is completely dried, the pine worms enter and lay eggs, which must be fumigated again, which requires great effort.
Even if the amount of the ultraviolet absorber added is too large, the durability against ultraviolet rays is not so much improved for the cost.
[0009]
In the coating sheet for fumigation of the present invention, 0.01 to 3 parts by weight of a light stabilizer is added with respect to 100 parts by weight of the biodegradable aliphatic polyester resin , and each is obtained alone by using in combination with an ultraviolet absorber. An improvement in weather resistance is observed. When the amount of the light stabilizer added is too small, the weather resistance is not so different from that of a fumigation coated sheet containing 5 parts by weight of an ultraviolet absorber. In addition, when the amount of the light stabilizer added is too large, the weather resistance is not significantly improved for an increase in cost.
[0010]
Examples of the light stabilizer used in the present invention include 2,2,6,6-tetramethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 2,2, 6,6-tetramethyl-4-piperidylbenzoate, N- (2,2,6,6-tetramethyl-4-piperidyl) dodecylsuccinimide, 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-piperidyl) sebacate, bis (1,2,2,6,6, -penta Til-4-piperidyl) -2-butyl-2- (3,5-di-tert-butyl-4-hydroxybenzyl) malonate, N, N′-bis (2,2,6,6-tetramethyl-4 -Piperidyl) hexamethylenediamine, tetra (2,2,6,6-tetramethyl-4-piperidyl) butanetetracarboxylate, bis (2,2,6,6-tetramethyl-4-piperidyl) di (tridecyl) Butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-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-tetraoxysaspiro [ , 5] undecane, 3,9-bis {1,1-dimethyl-2- [tris (1,2,2,6,6-pentamethyl-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-biperidyl) Butylamino] -1,3,5-triazin-2-yl} -1,5,8,12-tetraazadodecane, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4 -Piperidinol / dimethyl succinate condensate, 2-tert-octylamino-4,6-dichloro-s-triazine / N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylene Diamine Compounds, N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hindered amine light stabilizers such as hexamethylenediamine / dibromoethane condensate and the like.
[0011]
Moreover, 0.1-10 weight part of inorganic fillers are added with respect to 100 weight part of biodegradable aliphatic polyester resin . If the amount of the inorganic filler added is small, the sheet is blocked when heat is applied to the sheet, and it becomes difficult to unwind the fumigation-coated sheet. If the amount of the inorganic filler added is too large, the mechanical strength such as the tear strength is lowered, and it is likely to break by hitting a branch or the like during use, or to be easily broken by wind or the like.
[0012]
Examples of the inorganic filler that can be used in the present invention include talc, silica, feldspar, calcium carbonate, aluminum hydroxide, and hydrotalcite.
[0013]
The resin composition used in the present invention may contain a plasticizer, a pigment, an antioxidant, a lubricant, an antistatic agent, a colorant, an inorganic filler, an organic filler such as starch, and the like as necessary. good.
[0014]
As a method for forming the fumigation sheet, a forming method such as a calendering method, an extrusion method, or an inflation method can be used.
[0015]
The thickness of the fumigation sheet is preferably 0.05 to 0.3 mm, particularly preferably 0.1 to 0.2 mm.
When the thickness of the sheet is less than 0.05, the sheet tends to be broken and hit easily. If the thickness of the sheet is less than 0.1 mm, biodegradation is likely to proceed, and depending on the weather and soil quality, there may be holes in the part that is in contact with the ground before the fumigation work is completed, or the sheet is thin. As a result, the gas permeability is increased and the sealing performance may be impaired.
When the thickness of the sheet is greater than 0.3 mm, the sheet becomes heavy, and handling tends to be difficult, and flexibility tends to be low, making it difficult to perform the sealing operation. When the thickness of the sheet is greater than 0.2 mm, it takes time for biodegradation and tends to increase the time remaining in the environment.
[0016]
The fumigation work is performed after covering the fumigated material with the sheet of the present invention so that the gas does not leak or the fumigated material does not get wet in the rain.
The fumigation method is carried out by volatilizing or spraying the fumigant in the sheet. As a method of volatilizing, there are a method of natural evaporation and a method of heating a fumigant.
[0017]
【Example】
As an example, a sheet having a thickness of 0.1 mm was molded by an extrusion method using a T-die molding machine with the formulation described in Table 1.
The biodegradation residual rate was evaluated by burying a sheet cut to 10 cm × 10 cm in the soil in the field (Soil 1) and in the soil in the mountains of Nagano Prefecture (Soil 2), The weight residual rate after the year was measured.
A sheet of A4 size was horizontally fixed with a wooden frame at a distance of 20 cm from the ground, and the sheet left for half a year was visually evaluated. The neglected place is in Ashikaga Factory No. 1 at Achilles Corporation. The evaluation criteria are as follows.
○ There is no particular change in appearance. △ The sheet is partially torn × It is torn greatly, and even if it is broken by hand, two 6cm x 6cm films are overlapped, and 1kg weight is put on, 4 at 90 ° C Heating was performed for an hour, and blocking resistance was evaluated. The evaluation criteria are as follows.
○ Easy to peel △ Some resistance to peeling × Not peeled at all 【0018】
[Table 1]
* 1: Cell Green PH7 (manufactured by Daicel Chemical Industries)
* 2: Bionore # 1001 (made by Showa Polymer Co., Ltd.)
* 3: Bionore # 3001 (made by Showa Polymer Co., Ltd.)
* 4: Rakuti # 5000 (manufactured by Shimadzu Corporation)
* 5: Degree of polymerization 1400, 45 parts by weight of DOP added * 6: Vinyl acetate content 10% by weight
* 7: Biosorb 130 (benzophenone UV absorber; manufactured by Kyodo Yakuhin Co., Ltd.)
[0019]
As a comparative example, a sheet having a thickness of 0.1 mm was molded by an extrusion method using a T-die molding machine with the formulation described in Table 2.
The biodegradation residual rate and the evaluation of the sheet after the fumigation work were evaluated by the same method as in the examples.
[0020]
[Table 2]
* 1 to 7 are the same as in Table 1. [0021]
【The invention's effect】
The fumigation sheet of the present invention can greatly reduce the cost and labor of collecting and cleaning the fumigation coated sheet by adopting the above-described configuration, and the fumigant leakage due to deterioration of the sheet during the fumigation process. In addition, it is possible to prevent the fumigated material from getting wet by rain.

Claims (2)

It is obtained by adding 0.05 to 5 parts by weight of an ultraviolet absorber, 0.1 to 10 parts by weight of an inorganic filler , and 0.01 to 3 parts by weight of a light stabilizer with respect to 100 parts by weight of a biodegradable aliphatic polyester resin. A coating sheet for fumigation, which is a sheet obtained by molding a resin composition and is used when fumigation is performed on a material to be fumigated. The coating sheet for fumigation according to claim 1 , which has a thickness of 0.05 to 0.3 mm.