JP2021169618A - Water-soluble film for chlorine agent packaging - Google Patents

Abstract

To provide a water-soluble film for chlorine agent packaging that has high safety and handleability even when used as a chlorine agent packaging material, and can maintain excellent solubility for a long time.SOLUTION: The present invention provides a water-soluble film for chlorine agent packaging for packaging a chlorine agent, where the water-soluble film contains a water-soluble resin, and has a chlorine gas capturing material, which can capture a chlorine gas, on the film surface.SELECTED DRAWING: None

Description

INDUSTRIAL APPLICABILITY The present invention is a water-soluble film for packaging chlorine-based chemicals, which can obtain high safety and handleability even when used as a packaging material for chlorine-based chemicals, and can maintain excellent solubility for a long period of time. Regarding.

In recent years, various chemicals such as pesticides, detergents, and fungicides are sealed and packaged in a water-soluble film, put into water in the same package form at the time of use, and the contents are dissolved or dispersed in water together with the packaging film for use. Many methods have been used. The advantages of such a packaging method are that it can be used without direct contact with dangerous chemicals during use, that a certain amount is packaged so that it does not need to be weighed during use, and that the container or bag in which the chemical is packaged or transported, etc. Post-use processing is unnecessary or simple.
As a raw material for such a water-soluble film for packaging, a partially saponified PVA or a carboxylic acid-modified PVA film has been used. These water-soluble films are easily soluble in cold water, have excellent mechanical strength, and have good performance.

On the other hand, many chemicals such as pesticides, detergents and fungicides for which a water-soluble film for packaging is desired to be used contain chlorine. However, when a chlorine-containing drug is packaged, the solubility of the film decreases over time during packaging, making it insoluble or sparingly soluble during long-term storage, making it difficult to use in this field. There was a problem. In addition, since chlorine-containing chemicals are dangerous to the touch with bare hands, they are usually tableted for the purpose of improving handleability, but they become insoluble or sparingly soluble during the long-term storage. In some cases, it was finally necessary to take it out of the bag at the time of use.

On the other hand, Patent Document 1 discloses a packaging material containing a predetermined amount of polyvinyl alcohol resin, hydrotalcite compounds and zinc oxide as a packaging material for encapsulating a halogen-containing drug.
However, as described in Patent Document 1, when the inorganic compound is added to the film material, the film material is permeated before the halogens reach the inorganic compound, so that the film material is deteriorated first. Further, when the interfacial adhesive force between the inorganic substance and the film material is not sufficient, there is a problem that halogens penetrate deeper into the film through the interface and permeate faster, so that deterioration reaches a deep part at an early stage.

Japanese Patent No. 5143845

INDUSTRIAL APPLICABILITY The present invention is a water-soluble film for packaging chlorine-based chemicals, which can obtain high safety and handleability even when used as a packaging material for chlorine-based chemicals, and can maintain excellent solubility for a long period of time. The purpose is to provide.

The present invention is a water-soluble film for packaging chlorine-based chemicals for packaging chlorine-based chemicals, and has a chlorine-based gas trapping substance containing a water-soluble resin and capable of trapping chlorine-based gas on the film surface. A water-soluble film for packaging chlorine-based chemicals.
Hereinafter, the present invention will be described in detail.

When the present inventors arrange a chlorine-based gas trapping substance capable of trapping chlorine-based gas on the surface of a film containing a water-soluble resin, and use it as a packaging material for a chlorine-containing drug. However, they have found that it is possible to maintain excellent water solubility for a long period of time, and have completed the present invention. Further, the water-soluble film for packaging chlorine-based chemicals of the present invention can realize high film slipperiness and blocking resistance, and can improve mechanical suitability when packaging chlorine-based chemicals.
The details of the present invention will be described below.

[Water-soluble resin]
The water-soluble resin according to the present invention is a substance that is a main material of a water-soluble film for packaging chlorine-based chemicals.
Examples of the water-soluble resin include nonionic polymers such as polyvinyl alcohol, polyvinyl acetal, polyacrylamide, polyethylene oxide, polymethylvinyl ether, and polyisopropylacrylamide, sodium polyacrylic acid and its copolymer, and sodium polystyrene sulfonate. , Polyisoprenate sodium copolymer, naphthalene sulfonic acid condensate salt, anionic polymer such as polyethyleneiminzanate salt, dimethylaminoethyl (meth) acrylate quaternary salt alone and copolymer, dimethyldialylammonium chloride Acrylic resin, polyester resin, polyurethane resin, polyether resin, as well as cationic polymers such as monopoly and copolymer, polyamidine and its copolymer, polyvinyl imidazoline, dicyandiamide-based condensate, epichlorohydrin dimethylamine condensate, polyethyleneimine, etc. , Polyalkylene glycol, polyvinylpyrrolidone and its copolymers, starches such as starch, carboxymethyl starch, phosphate starch, cationic starch and derivatives thereof, dextrin, cellulose, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, cellulose such as carboxymethylcellulose. Examples thereof include polysaccharides such as derivatives, cellulose guar gum, xanthan gum, alginic acid, arabic gum, carrageenan, sodium chondroitin sulfate, sodium hyaluronate, chitosan, gelatin and other naturally derived polymers.
Further, the above-mentioned polyvinyl alcohol, modified polyvinyl alcohol obtained by modifying polyvinyl acetal, modified polyvinyl acetal and the like can be mentioned. Of these, polyvinyl alcohol and modified polyvinyl alcohol are preferable.
Further, as the water-soluble resin, a resin to which a hydroxyl group is added may be used. Examples of such a resin include a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, a hydroxyl group-containing polyurethane resin, and a hydroxyl group-containing polyether resin.
The water-soluble resin refers to a resin that dissolves in 95% by weight or more when dissolved in water at 23 ° C.

When polyvinyl alcohol (hereinafter, may be referred to as PVA) is used as the water-soluble resin, the saponification degree of the polyvinyl alcohol has a preferable lower limit of 50 mol% and a preferable upper limit of 100 mol%. By setting the degree of saponification to the lower limit or higher, the physical strength can be more effectively expressed when the film is formed. The degree of saponification of PVA used is appropriately determined by the balance between the physical characteristics of the target film and the water solubility.
The more preferable lower limit of the degree of saponification is 70 mol%, the more preferable lower limit is 80 mol%, and the more preferable upper limit is 99.5 mol%. A more preferred upper limit is 99 mol%.

The degree of saponification is measured according to JIS K6726. The degree of saponification indicates the ratio of units that are actually saponified to vinyl alcohol units among the units that are converted to vinyl alcohol units by saponification.
The method for adjusting the degree of saponification is not particularly limited. The degree of saponification can be appropriately adjusted depending on the saponification conditions, that is, the hydrolysis conditions.

The degree of polymerization of the PVA is not particularly limited, but the preferred lower limit is 300 and the preferred upper limit is 5000. A more preferable lower limit is 500, and a more preferable upper limit is 3000. When the degree of polymerization is not less than the above lower limit and not more than the above upper limit, both the physical characteristics of the film and the film-forming property can be compatible at a high level. The degree of polymerization is measured according to JIS K6726.

The PVA may be a mixture of two or more types of PVA having different degrees of saponification, degree of polymerization, etc., or may be a mixture of a modified product and an unmodified product. By using such a mixed PVA, the resin or modified product having a low degree of saponification exerts the effect of lowering the actual flow start temperature, so that the film-forming temperature can be further lowered. Furthermore, both water solubility and film physical characteristics can be achieved at a higher level.

The polyvinyl alcohol can be obtained by polymerizing a vinyl ester to obtain a polymer and then saponifying, that is, hydrolyzing the polymer according to a conventionally known method. Alkali or acid is generally used for saponification. It is preferable to use alkali for saponification. As the polyvinyl alcohol, only one kind may be used, or two or more kinds may be used in combination.

Examples of the vinyl ester include vinyl acetate, vinyl formate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl versatic acid, vinyl laurate, vinyl stearate, vinyl benzoate and the like. Since it is easy to control the degree of saponification within a suitable range, the polymer obtained by polymerizing the vinyl ester is preferably a polyvinyl ester.

The polymerization method of the vinyl ester is not particularly limited. Examples of this polymerization method include a solution polymerization method, a massive polymerization method, and a suspension polymerization method.

Examples of the polymerization catalyst used when polymerizing the vinyl ester include 2-ethylhexyl peroxydicarbonate (“TrigonoxEHP” manufactured by Tianjin McEIT), 2,2'-azobisisobutyronitrile (AIBN), and t-butyl. Peroxyneodecanoate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-n-propyl peroxydicarbonate, di-n-butylperoxydicarbonate, di-cetylperoxydicarbonate and di-s-butylperoxy Dicarbonate and the like can be mentioned. Only one kind of the above-mentioned polymerization catalyst may be used, or two or more kinds thereof may be used in combination.

The polyvinyl alcohol includes modified polyvinyl alcohol (modified PVA).
The modified PVA may be a copolymer of the vinyl ester and another monomer, or may be a modified polyvinyl alcohol.
The modified polyvinyl alcohol includes, for example, acetoacetyl-modified polyvinyl alcohol, carboxyl-modified polyvinyl alcohol, sulfonic acid-modified polyvinyl alcohol, olefin-modified polyvinyl alcohol, nitrile-modified polyvinyl alcohol, amide-modified polyvinyl alcohol, pyrrolidone-modified polyvinyl alcohol, and silicon atom. Examples thereof include modified polyvinyl alcohol, and a graft polymer of polyvinyl alcohol and a copolymer of (acrylamide, vinylpyrrolidone, acrylonitrile).
Of these, pyrrolidone-modified polyvinyl alcohol is preferable.

Examples of the other monomers to be copolymerized include olefins, (meth) acrylic acid and salts thereof, (meth) acrylic acid esters, (meth) acrylamide derivatives, N-vinylamides, vinyl ethers, and the like. Examples thereof include nitriles, vinyl halides, allyl compounds, maleic acid and salts thereof, maleic acid esters, itaconic acids and salts thereof, itaconic acid esters, vinylsilyl compounds, polyvinylpyrrolidone, and isopropenyl acetate. As the other monomer, only one kind may be used, or two or more kinds may be used in combination.

Examples of the olefins include ethylene, propylene, 1-butene and isobutene. Examples of the (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, and n-propyl (meth) acrylate. Examples thereof include butyl and 2-ethylhexyl (meth) acrylate. Examples of the (meth) acrylamide derivative include acrylamide, n-methylacrylamide, N-ethylacrylamide, N, N-dimethylacrylamide, (meth) acrylamide propanesulfonic acid and salts thereof. Examples of the N-vinylamides include N-vinylpyrrolidone and the like. Examples of the vinyl ethers include methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether and n-butyl vinyl ether. Examples of the nitriles include (meth) acrylonitrile. Examples of the vinyl halides include vinyl chloride and vinylidene chloride. Examples of the allyl compound include allyl acetate and allyl chloride. Examples of the vinylsilyl compound include vinyltrimethoxysilane.

The preferred upper limit of the amount of modification (ratio of modified constituent units) in the modified polyvinyl alcohol is 25 mol%, and the more preferable upper limit is 20 mol%. A more preferred upper limit is 15 mol%. The preferable lower limit of the modification amount is 2 mol%. Within the above range, both the physical characteristics of the film as a packaging material and the water solubility can be achieved at a high level.

The content of the water-soluble resin used in the present invention is preferably 60 to 99.8% by weight. By setting the above content to 60% by weight or more, sufficient film physical characteristics can be obtained even when used as a packaging material for chlorine-containing chemicals. Thereby, high chemical resistance, particularly high chlorine resistance can be imparted. As the water-soluble resin, a single resin may be used, or several kinds of resins may be mixed, but the total amount of the water-soluble resin should be adjusted so as to be within this range. The more preferable lower limit of the content is 70% by weight, and the more preferable upper limit is 95% by weight. A more preferable lower limit is 80% by weight, and a further preferable upper limit is 92% by weight.

[Chlorine-based gas trapping substance]
The chlorine-based gas trapping substance used in the present invention is not particularly limited as long as it is a substance capable of trapping chlorine-based gas, but an inorganic adsorbent or an inorganic absorbent is preferable. Examples of these substances include layered double hydroxides and silicates. Examples of the layered double hydroxide include carbonates such as hydrotalcites. Examples of the carbonate include anhydrous sodium carbonate and the like. Examples of the silicate include aluminosilicates such as zeolites and silicic anhydride (silica). These are not particularly limited, but in the case of zeolite, a smaller silica / alumina ratio tends to be more preferable, and the ratio is preferably 5 or less, more preferably 3 or less.

The hydrotalcites are compounds having the same crystal structure as hydrotalcite and hydrotalcite.
The hydrotalcites are preferably substances represented by the following formula (1).

式（１）中、Ｍ^２＋は、Ｍｇ、Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ、Ｃｕ及びＺｎからなる群から選ばれる少なくとも１種の２価金属イオンを表し、Ｍ^３＋はＡｌ、Ｃｒ、Ｆｅ、Ｃｏ及びＩｎからなる群から選ばれる少なくとも１種の３価金属イオンを表し、Ａ^ｎ−は、ＮＯ_３ ⁻、Ｃｌ⁻及びＣＯ_３ ^２−からなる群から選ばれる少なくとも１種のｎ価陰イオンを表す。ｘは０超過１未満の数を表し、ｎは陰イオンの価数を表し、ｙは水和水の数を表す。

In the formula (1), M ²⁺ represents at least one divalent metal ion selected from the group consisting of Mg, Mn, Fe, Co, Ni, Cu and Zn, and M ³⁺ represents Al, Cr, Fe and Co. and represents at least one trivalent metal ion selected from the group consisting of an ^{in, a} _n-is, ^NO 3 ^_-, Cl - and _CO ³ at least one of n dianion selected from the group consisting of ^2- show. x represents a number exceeding 0 and less than 1, n represents the valence of anion, and y represents the number of hydrated water.

The hydrotalcites are a positively charged bluesite-type basic layer ([M 2 ⁺ _1-x M ^{3 +} _x (OH) ₂ ]) and a negatively charged intermediate layer consisting of anions and interlayer water ([A]. ^{It is a layered structure compound composed of n−} _{x / n} · yH ₂ O]), and maintains electrical neutrality in the entire crystal. Having the structure as described above makes it possible to preferably capture chlorine-based gas.
Examples of the hydrotalcites include Mg _4.3 Al ₂ (OH) _12.6 CO ₃ · mH ₂ O and the like.

The zeolite is a crystalline aluminosilicate and is a substance represented by the following formula (2).

式（２）中、Ｍ^Ｉは１価カチオン、Ｍ^ＩＩは２価カチオンを表す。ｍ及びｎは整数を表し、ｘは１以上の数を表す。

Wherein (2), ^{M I} is a monovalent ^{cation, M II} represents a divalent cation. m and n represent integers, and x represents a number of 1 or more.

As the zeolite, either a hydrophilic zeolite or a hydrophobic zeolite may be used.
The higher the Al / Si ratio, the larger the amount of commutative cations contained in the above-mentioned zeolite, so that the zeolite has high polarity and high hydrophilicity. The preferred Al / Si ratio is 0.4 to 1.0, more preferably 0.8 to 1.0.
As the above-mentioned zeolite, a synthetic zeolite is preferable because the Al / Si ratio is stable. For example, zeolite A: Na ₁₂ (Al ₁₂ Si ₁₂ O ₄₈ ) · 27H ₂ O; Al / Si ratio 1.0, Zeolite X: Na ₈₆ (Al ₈₆ Si ₁₀₆ O ₃₈₄ ) · 264H ₂ O; Al / Si ratio 0.811, Zeolite Y: Na ₅₆ (Al ₅₆ Si ₁₃₆ O ₃₈₄ ) · 250H ₂ O; Al / Si ratio 0. 412 and the like can be mentioned.

The chlorine-based gas trapping substance is preferably in the form of particles. In this case, the preferable lower limit of the average particle size for the chlorine-based gas trapping substance to exert a sufficient effect without falling off from the film surface is 0.1 μm, and the preferable upper limit is 100 μm.
Further, the chlorine-based gas trapping substance preferably has a porous shape.

The chlorine-based gas trapping substance preferably has a NaCl-converted chlorine-based gas trapping ability measured by fluorescent X-rays of 0.15 to 3.0 in comparison with sodium carbonate. This makes it possible to properly supplement the chlorine-based gas. By setting the NaCl-equivalent chlorine-based gas trapping ability to 0.15 or more, it is possible to secure the necessary chlorine-based gas supplementing ability, and by setting the NaCl-equivalent chlorine-based gas trapping ability to 3.0 or less, it is alkaline. Can be prevented from adversely affecting the film due to the action of moisture absorption or the like without becoming very strong. The more preferable lower limit of the NaCl-converted chlorine-based gas trapping ability is 0.2.
The chlorine-based gas trapping ability is calculated by preparing a calibration curve in advance, measuring the amount of chlorine adsorbed on the sample with a fluorescent X-ray, and using the calibration curve to calculate the chlorine concentration in terms of sodium chloride. Then, by dividing the sodium chloride-equivalent chlorine concentration by the sodium chloride-equivalent chlorine concentration obtained for sodium carbonate, the NaCl-equivalent chlorine-based gas trapping ability (compared to sodium carbonate) can be obtained.

The water-soluble film for packaging chlorine-based chemicals of the present invention is not particularly limited as long as it has a chlorine-based gas trapping substance on the film surface. Having on the film surface means that a part or all of the chlorine-based gas trapping substance is exposed on the film surface. Specifically, for example, a surface layer containing the chlorine-based gas trapping substance is provided on the film surface. Examples thereof include a holding state, a state of being attached to the film surface by physical adsorption, and a state of being bonded to the film surface by chemical bonding.

In the water-soluble film for packaging chlorine-based chemicals of the present invention, the content of the chlorine-based gas trapping substance per unit area is preferably ^{0.05 to 3 g / m 2.} By at 0.05 g / m ² or more, it is possible to obtain a sufficient chlorine gas trapping ability, it is 3 g / m ² or less, the heat chlorine gas trapping agent is chlorine drug packaging water-soluble film It is possible to prevent the seal and the like from being hindered. The content of the chlorine-based gas trapping substance per unit area means the amount of the chlorine-based gas trapping substance adhering to the area of the main surface of the water-soluble film for packaging chlorine-based chemicals.
The content of such a chlorine-based gas trapping substance per unit area can be calculated by measuring the weight before and after the adhesion.

In the water-soluble film for packaging chlorine-based chemicals of the present invention, the content per unit area of the chlorine-based gas trapping substance remaining after washing with hexane (B) with respect to the content (A) of the chlorine-based gas trapping substance per unit area. ) Is preferably 0.5 or less. Note that A is calculated from the difference in film weight before and after applying the chlorine-based gas trapping substance.
When the B / A is 0.5 or less, it is important that a large amount of chlorine-based gas trapping substance exists on the surface of the water-soluble film for packaging chlorine-based chemicals. As a result, high chlorine resistance can be obtained, and excellent water solubility can be maintained for a long period of time. The B / A is more preferably 0.3 or less, and further preferably 0.2 or less.

(Plasticizer)
The water-soluble film for packaging chlorine-based chemicals of the present invention preferably contains a plasticizer.
By containing the above-mentioned plasticizer, it is possible to lower the glass transition point and improve the durability at low temperature. Further, by containing the above-mentioned plasticizer, the solubility of the water-soluble film for packaging chlorine-based chemicals in water can be improved.

The above-mentioned plasticizing agent is not particularly limited as long as it is generally used as a plasticizing agent for PVA, and examples thereof include glycerin, diglycerin, diethylene glycol, trimethylolpropane, triethylene glycol, dipropylene glycol and propylene glycol. Polyhydric alcohols, polyethers such as polyethylene glycol and polypropylene glycol, phenol derivatives such as bisphenol A and bisphenol S, amide compounds such as N-methylpyrrolidone, and ethylene oxide in polyhydric alcohols such as glycerin, pentaerythritol, and sorbitol. Examples thereof include added compounds and water. These may be used alone or two or more kinds may be used.
Among the above plasticizers, glycerin, trimethylolpropane, polyethylene glycol, polypropylene glycol, triethylene glycol, dipropylene glycol, and propylene glycol are preferable because they can improve water solubility, and the effect of improving water solubility is particularly large. Therefore, glycerin and trimethylol propane are particularly preferable.

The water-soluble film for packaging chlorine-based chemicals of the present invention preferably contains 3 to 15 parts by weight of the above-mentioned plasticizer with respect to 100 parts by weight of the water-soluble resin. The more preferable lower limit of the plasticizer content is 3.2 parts by weight, and the more preferable upper limit is 13 parts by weight.

The thickness of the water-soluble film for packaging chlorine-based chemicals of the present invention has a preferable upper limit of 100 μm, a more preferable upper limit of 80 μm, and a further preferable upper limit of 75 μm. The preferable lower limit of the thickness of the water-soluble packaging film of the present invention is 10 μm. When the thickness of the water-soluble film for packaging chlorine-based chemicals of the present invention is at least the above lower limit, the strength of the film for packaging chemicals becomes even higher. When the thickness of the water-soluble film for chlorine-based chemical packaging of the present invention is not more than the above upper limit, the packaging property and heat-sealing property of the water-soluble packaging film are further improved, and the processing time is further shortened for production. The sex becomes even higher.

The water-soluble film for packaging chlorine-based chemicals of the present invention is further supplemented with ordinary additives such as a colorant, a fragrance, a bulking agent, a defoaming agent, a release agent, an ultraviolet absorber, a surfactant, and starch as appropriate. It does not matter if it is mixed. In particular, in order to improve the peelability between the metal surface of a film-forming device such as a die or drum and the film-formed film or film stock solution, 0.01 to 5 weight of a surfactant is added to 100 parts by weight of the water-soluble resin. It is preferable to mix in a proportion of parts.

(Manufacturing method of water-soluble film for chlorine-based chemical packaging)
Examples of the method for producing the water-soluble film for packaging chlorine-based chemicals of the present invention include a method of first producing an untreated water-soluble film and then applying a chlorine-based gas trapping substance.

The method for producing the untreated water-soluble film is not particularly limited, but a method of casting a water-soluble resin solution containing a water-soluble resin, a plasticizer, and a solvent on a support member and drying the film can be used. Specific examples thereof include a solution casting method (casting method).
Further, a molding method such as a method of performing a step of extruding into a thin film by a mold after melting with an extruder may be used. As a specific molding method, known molding methods such as extrusion molding, inflation molding, injection molding, blow molding, vacuum molding, pressure molding, compression molding, and calendar molding can be used. Of these, it is preferable to use a solution casting method or an extrusion molding method.
Examples of the method for applying the chlorine gas trapping substance include a simple sprinkling method, an electrostatic adsorption method, a roll coating method, a spin coating method, a screen coating method, a fountain coating method, a dipping method and a spray method.

Examples of the method of applying the chlorine-based gas trapping substance include a method of laminating a surface layer containing the chlorine-based gas trapping substance on an untreated water-soluble film and spraying a dispersion liquid containing the chlorine-based gas trapping substance. Methods, methods such as immersing an untreated water-soluble film in a dispersion, spraying a chlorine-based gas trapping substance on the untreated water-soluble film, spraying a chlorine-based gas trapping substance, and crimping with a roll or the like. Can be mentioned.
Examples of the method of laminating the surface layer containing the chlorine-based gas trapping substance on the untreated water-soluble film include a method of applying and drying a dispersion liquid containing the chlorine-based gas trapping substance, and a chlorine-based gas trapping substance. Examples thereof include a method of laminating a surface layer film containing.

The water-soluble film for packaging chlorine-based chemicals of the present invention can be suitably used for packaging chlorine-based chemicals. By using the water-soluble film for packaging chlorine-based chemicals of the present invention, it is possible to prevent the water-soluble property from decreasing with time and maintain excellent water-soluble property for a long period of time.
The chlorine-based chemicals refer to chemicals that release chlorine-based gases such as chlorine gas, hypochlorous acid gas, and hydrogen chloride under the conditions of 23 ° C. and 50% humidity. Specific examples thereof include dichloroisocyanuric acid, sodium dichloroisocyanuric acid, trichloroisocyanuric acid, sodium hypochlorite, calcium hypochlorite, trichloronitromethane and the like.
In addition, examples of the chlorine-based chemicals include pesticides, detergents, fungicides, water treatment agents, chlorinating agents, deodorants and the like.

According to the present invention, even when used as a packaging material for chlorine-based chemicals, high safety and handleability can be obtained, and chlorine-based chemical packaging water capable of maintaining excellent solubility for a long period of time. Soluble films can be provided.

Hereinafter, embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Example 1)
100 parts by weight of pyroridone-modified polyvinyl alcohol (PVP-modified PVA, degree of polymerization 1000, degree of saponification 95.8 mol%, amount of pyrrolidone modification 4 mol%), 5 parts by weight of plasticizer (trimethylolpropane), and 400 parts by weight of water are mixed. Then, a pyrrolidone-modified PVA-containing resin composition was obtained. The obtained pyrrolidone-modified PVA-containing resin composition was coated on an OPP film using a baker-type film applicator, dried in an 80 ° C. warm air circulation oven for 30 minutes, and then the OPP film was peeled off. As a result, a water-soluble film having a thickness of 50 μm was obtained.
Using a powder spray device (manufactured by Nikka, "K-III"), the obtained water-soluble film is water-soluble so that the content of hydrophilic zeolite per unit area is 1.9 g / m ^2. Hydrophilic zeolite (surface adduct) was sprayed on the front surface and the back surface of the sex film to obtain a water-soluble film for packaging. As the hydrophilic zeolite, molecular sieve 5A (manufactured by Union Showa Co., Ltd., structure: Na ₈ Ca ₂ [(AlO ₂ ) ₁₂ (SiO ₂ ) ₁₂ ] · 27H ₂ O, average particle size: 10 μm or less, average pore size : 0.42 nm) was used.

The NaCl-equivalent chlorine-based gas trapping ability (contrast with sodium carbonate) of the hydrophilic zeolite used was measured by the following method.

(Measurement of NaCl-equivalent chlorine-based gas trapping ability)
3%, 10%, and 20% of crushed sodium chloride were mixed with 100 mg of a hydrophilic zeolite sample, placed in a sample container for fluorescent X-ray fluorescence (capacity 0.5 mL), and from the obtained measurement results, sodium chloride was measured on the x-axis. The fluorescence X-ray intensity (cps / μA) per unit current and unit time of chlorine was set on the y-axis, and a calibration curve was prepared. A calibration curve was prepared in the same manner for crushed sodium carbonate.
Next, 50 mg of a hydrophilic zeolite sample was placed in a sample container for fluorescent X-rays (volume 0.5 mL), and the mixture was sealed in a 500 mL glass airtight container together with 15 g of trichloroisocyanuric acid. After heating the above closed container in a circulation type oven at 60 ° C. for 24 hours, the sample container was taken out, mixed again, and the amount of chlorine adsorbed on the sample was measured by fluorescent X-ray. The measured fluorescent X-ray intensity (cps / μA) per unit current and unit time of chlorine was calculated to the sodium chloride-equivalent chlorine concentration using a calibration curve.
By dividing the sodium chloride-equivalent chlorine concentration obtained for each sample by the sodium chloride-equivalent chlorine concentration obtained for sodium carbonate, the sodium chloride-equivalent chlorine concentration standardized with sodium carbonate was obtained and used as the chlorine-based gas trapping ability.
The fluorescent X-ray intensity was analyzed under the following conditions using a fluorescent X-ray analyzer (manufactured by Shimadzu Corporation, equipped with EDX-800HS, Si (Li) semiconductor detector).
X-ray tube: Rh tube (25W)
Measurement X-ray: Kα
Applied voltage: 20kV
Filter: Aluminum Measurement time: 100 seconds Atmosphere: Vacuum measurement diameter: 5 mm

(Examples 2 to 4, 8)
The following substances were used in place of the hydrophilic zeolite (Molecular Sieve 5A), and a water-soluble film for packaging was obtained in the same manner as in Example 1 except that the content per unit area was changed to the amount shown in Table 1.
Example 2: Hydrophobic zeolite (manufactured by Union Showa Co., Ltd .: Abcents 3000, average particle size: 5 μm, average pore size: 0.6 nm)
Example 3: Hydrotalcite (manufactured by Kyowa Chemical Industry Co., Ltd .: DHT-4A, structure: Mg _4.3 Al ₂ (OH) _12.6 CO ₃ · mH ₂ O, average particle size: 0.45 μm)
Example 4: Sodium carbonate anhydride (manufactured by Tokuyama Corporation: crushed light ash, structure: Na ₂ CO ₃ , average particle size: 5 μm)
Example 8: Crushed silica (manufactured by Ryumori Co., Ltd .: CMC-12S, structure: SiO ₂ , average particle size: 5 μm)

(Example 5)
Partially saponified polyvinyl alcohol (polymerization degree 1300, saponification degree 88) instead of 100 parts by weight of pyrrolidone-modified polyvinyl alcohol (PVP-modified PVA, degree of polymerization 1000, saponification degree 95.8 mol%, pyrrolidone modification amount 4 mol%) 0.0 mol%, 4 wt% aqueous solution viscosity 14 mPa · s) 100 parts by weight was used. Further, a water-soluble film for packaging was obtained in the same manner as in Example 1 except that the content of hydrophilic zeolite per unit area was 2.1 g / m ^2.

(Examples 6 and 7)
A water-soluble film for packaging was obtained in the same manner as in Example 1 except that the content of hydrophilic zeolite per unit area was changed to the amount shown in Table 1.

(Comparative Example 1)
The 50 μm-thick water-soluble film (before spraying the hydrophilic zeolite) produced in Example 1 was used as the film of Comparative Example 1.

(Comparative Example 2)
The 50 μm-thick water-soluble film (before spraying the hydrophilic zeolite) produced in Example 5 was used as the film of Comparative Example 2.

(Comparative Example 3)
100 parts by weight of pyrrolidone-modified polyvinyl alcohol (PVP-modified PVA, degree of polymerization 1000, degree of saponification 95.8 mol%, amount of pyrrolidone modification 4 mol%), 5 parts by weight of plasticizer (trimethylol propane), hydrophilic zeolite (molecular sieve) 5A) 2 parts by weight and 400 parts by weight of water were mixed to obtain a pyrrolidone-modified PVA-containing resin composition. The obtained pyrrolidone-modified PVA-containing resin composition was coated on an OPP film using a baker-type film applicator, dried in an 80 ° C. warm air circulation oven for 30 minutes, and then the OPP film was peeled off. As a result, a water-soluble film having a thickness of 50 μm was obtained.

(evaluation)
(1) Water solubility (solubility)
The obtained film was allowed to stand at 20 ° C. and 50% RH for 15 hours or more, and then cut into 3 × 1.5 cm test pieces. Then, the weight (Ws) of the test piece was measured, the test piece and 12 ml of water were put into a 20 ml container, and then the test piece and 12 ml of water were shaken at 180 rpm for 10 minutes.
Further, after filtering with a weighed stainless steel 200 mesh filter (Wm), the mesh filter was dried at 80 ° C. for 1 hour. Then, the weight (Wt) of the mesh filter after standing at 23 ° C., 50% RH, and 15 hours or more was measured, and the dissolution rate was measured from the following formula.

Dissolution rate (%) = [Ws- (Wt-Wm)] / Ws × 100 (%)

(2) Chemical resistance The obtained film was allowed to stand at 20 ° C. and 50% RH for 15 hours or more, and then cut into 8 × 14 cm test pieces. Next, a tablet of trichloroisocyanuric acid (φ30 mm × 15 mm 30 g) was wrapped with a 6 × 12 cm non-woven fabric (PE & PP), further wrapped with a test piece, and the three sides of the test piece were sealed with a width of 1 cm to obtain a measurement sample. rice field.
The obtained measurement sample was placed in a 500 ml sealed container and allowed to stand at 60 ° C. for 24 hours, then the measurement sample was taken out and a tablet of trichloroisocyanuric acid was taken out from the measurement sample. Next, the chemical resistance of the central portion of the test piece in the measurement sample was evaluated by performing the same measurement as in "(1) Water solubility (solubility)".
The chemical resistance was also evaluated in the same manner when the measurement sample was "standing at 60 ° C. for 48 hours".

(3) Surface adduct content ratio before and after cleaning with organic solvent The obtained film was wiped with a waste cloth using hexane, and from the difference in film weight before and after wiping, the unit of surface adduct remaining after washing with organic solvent. The content (B) per area was measured. Next, the ratio (B / A) of the surface adduct to the content (A) per unit area before washing with hexane was calculated. Note that A was calculated from the difference in film weight before and after spraying the surface adduct.

According to the present invention, even when used as a packaging material for chlorine-based chemicals, high safety and handleability can be obtained, and chlorine-based chemical packaging water capable of maintaining excellent solubility for a long period of time. Soluble films can be provided.

Claims (10)

A water-soluble film for packaging chlorine-based chemicals for packaging chlorine-based chemicals.
Contains water-soluble resin,
A water-soluble film for packaging chlorine-based chemicals, which comprises a chlorine-based gas trapping substance capable of capturing chlorine-based gas on the film surface. The chlorine-based chemical packaging water according to claim 1, wherein the chlorine-based gas trapping substance has a NaCl-converted chlorine-based gas trapping ability measured by fluorescent X-rays of 0.15 to 3.0 in comparison with sodium carbonate. Soluble film. The water-soluble film for packaging chlorine-based chemicals according to claim 1 or 2, wherein the chlorine-based gas trapping substance is in the form of particles. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2 or 3, wherein a surface layer containing a chlorine-based gas trapping substance is provided on the film surface. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2 or 3, wherein the chlorine-based gas trapping substance is attached to the film surface by physical adsorption. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2, 3, 4 or 5, wherein the content of the chlorine-based gas trapping substance per unit area is 0.05 to 3 g / m ^2. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2, 3, 4, 5 or 6, wherein the chlorine-based gas trapping substance contains a substance represented by the following formula (1).

In the formula (1), M ²⁺ represents at least one divalent metal ion selected from the group consisting of Mg, Mn, Fe, Co, Ni, Cu and Zn, and M ³⁺ represents Al, Cr, Fe and Co. and represents at least one trivalent metal ion selected from the group consisting of an ^{in, a} _n-is, ^NO 3 ^_-, Cl - and _CO ³ at least one of n dianion selected from the group consisting of ^2- show. x represents a number exceeding 0 and less than 1, n represents the valence of anion, and y represents the number of hydrated water. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the chlorine-based gas trapping substance contains a substance represented by the following formula (2).

Wherein (2), ^{M I} is a monovalent ^{cation, M II} represents a divalent cation. m and n represent integers, and x represents a number of 1 or more. The B / A indicating the content (B) per unit area of the chlorine-based gas trapping substance remaining after washing with hexane is 0.5 or less with respect to the content (A) per unit area of the chlorine-based gas trapping substance. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2, 3, 4, 5, 6, 7 or 8. The water-soluble film for packaging chlorine-based chemicals according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9, wherein the water-soluble resin is polyvinyl alcohol.