KR19980086384A - Antimicrobial Vinyl Chloride Resin Composition - Google Patents

Abstract

The present invention provides an antimicrobial vinyl chloride resin composition useful as a molding raw material for an antimicrobial food packaging film. The resin composition is selected from (1) 100 parts by weight of a vinyl chloride resin, (2) 0.01 to 1.00 parts by weight of an antimicrobial inorganic compound selected from an inorganic silver compound and an inorganic zinc compound, (3) a glycerin fatty acid ester and a polyoxyethylene alkyl ether. The resin film obtained by molding the resin composition comprises 0.1 to 5.0 parts by weight of the nonionic surfactant, 20 to 60 parts by weight of the plasticizer and 0.1 to 2.5 parts by weight of the calcium / zinc stabilizer. It has the advantage of exerting a uniform and reproducible antimicrobial performance for a long time.

Description

Antimicrobial Vinyl Chloride Resin Composition

The present invention relates to a vinyl chloride resin composition having an antimicrobial useful as a raw material of a resin film for food packaging, and an antimicrobial vinyl chloride resin film obtained by molding the composition.

Vinyl chloride-based resin films are consumed in large quantities as so-called wrap films used in food packaging materials such as meat, fresh fish, fruits and vegetables, and processed foods in the supermarket market. It is also used in restaurants and homes for the purpose of preserving cooking materials and cooked foods. At the present time, it is desired to provide antimicrobial activity to the wrap film from the viewpoint of increasing consumer hygiene and preventing food poisoning. It is common to add an antimicrobial agent to the vinyl chloride-type resin composition which comprises a wrap film, and the antimicrobial agent uses the antimicrobial inorganic compound containing metal elements, such as silver or zinc, from the standpoint of safety and antimicrobial performance, and uses them as a particle size An antimicrobial agent formed by supporting an inorganic fine powder of about 1 μm is widely used (see Japanese Patent Laid-Open No. 6-287324 and Japanese Patent Laid-Open No. 1-175814).

In these conventional vinyl chloride-based resin composition films containing an antimicrobial agent, antimicrobial particles are mixed and dispersed in the film, and among the mixed and dispersed antimicrobial particles, the microorganisms adhered to the film surface are exposed to the surface of the film. By preventing or contacting the film, the antimicrobial performance is imparted to the object to be exerted.

Therefore, it is preferable to exhibit sufficient antimicrobial activity over the entire surface of the film surface. To this end, it is necessary to make the mixed dispersion state of the antimicrobial powder extremely uniform or to add a large amount of the antimicrobial powder itself. However, adding and mixing these inorganic antimicrobial agents to vinyl chloride-based resins has a drawback that the light resistance of the film is considerably lowered, resulting in deterioration such as discoloration during storage and use. In addition, these antimicrobial agents exert antimicrobial activity only on the particles exposed from the surface of the film. Since the inorganic antimicrobial agent added itself is extremely stable, when added to a vinyl chloride resin composition together with a plasticizer, stabilizer, surfactant, and the like, the metal element components are excessively ionized by reaction with these additives, and as a result, molding There was a problem that the vinyl chloride-based resin composition film obtained by coloring was not colored, or the antibacterial performance was not sufficiently exhibited and thus not stabilized.

In particular, the antimicrobial agent containing silver compound as an active ingredient promotes oxidation of the film itself when the silver component is ionized. As a result, discoloration of the film cannot be suppressed and sufficient antibacterial performance cannot be exhibited. There was a problem that can not maintain a stable antimicrobial performance for a long time.

In addition, when the amount of the antimicrobial agent is added, the transparency of the film is lowered, and the moldability of the resin composition is formed into the film, and the antimicrobial agent is likely to cause plate out in the extruder or the die. As a result, the activity of the resin composition at the time of shaping | molding falls, As a result, the heat decomposition product of resin tends to arise at the time of a vinyl chloride type resin composition or shaping | molding process, and this decomposition product becomes a foreign material, it mixes in a film, and the quality deterioration is reduced. There was a problem that it was not possible to obtain a closed end or a stable molded article.

For this reason, the molded article obtained by using the conventional antimicrobial vinyl chloride-based resin composition described above, in particular, the film was not able to obtain a stable and stable antimicrobial performance over a long period of time, and could not prevent its discoloration or coloring. Therefore, it has been desired to solve the above-mentioned problems with respect to the vinyl chloride resin composition in which a vinyl chloride resin contains silver or zinc compound as an antimicrobial active ingredient, and moldings obtained from the composition, especially packaging films.

The present invention solves the above-mentioned problems and exhibits excellent antimicrobial performance which is stable and stable with respect to the entire surface of the film over a long period of time, and is suitable as a raw material of an antimicrobial vinyl chloride resin which does not cause discoloration or coloring. It is an object to provide a composition.

That is, the antimicrobial vinyl chloride resin composition provided by the present invention

(1) 100 parts by weight of vinyl chloride resin

(2) 0.01 to 1.00 parts by weight of an antimicrobial compound selected from an inorganic silver compound and an inorganic zinc compound, and

(3) A resin composition comprising 0.1 to 5.0 parts by weight of a nonionic surfactant selected from glycerin fatty acid esters and polyoxyethylene alkyl ethers.

In particular, in addition to the above essential components,

(4) 20 to 60 parts by weight of plasticizer and

(5) 0.1 to 2.5 parts by weight of calcium / zinc stabilizer

The vinyl chloride-based resin composition obtained by blending is suitable as a raw material of the antimicrobial resin film.

In addition, a vinyl chloride resin composition is particularly preferred in which the nonionic surfactant is a combination of 0.1 to 5.0 parts by weight of a surfactant selected from glycerin fatty acid ester and polyoxy ethylene alkyl ether and 0.3 to 1.0 part by weight of sorbitan fatty acid ester. Do.

Hereinafter, the present invention will be described in detail.

As a vinyl chloride type resin which is a 1st component used for this invention, the homopolymer of vinyl chloride which has an average degree of polymerization of 700-1700, especially 1000-1300 is preferable. In addition to the homopolymer of vinyl chloride, copolymers of vinyl chloride with an olefinic monomer which can be copolymerized therewith, graft copolymers obtained by graft polymerization of vinyl chloride to polymers other than the vinyl chloride polymer, and the like can be used. Since the mechanical properties deteriorate when the content of structural units other than vinyl chloride in the copolymer increases in the copolymer, the copolymer preferably contains 60% by weight or more of the vinyl chloride component. These vinyl chloride resins are used in one type or in combination of two or more types.

The olefin monomer copolymerizable with vinyl chloride may be one having a polymerizable double bond in the molecule, and examples thereof include α-olefins such as ethylene, propylene and butene, vinyl esters such as vinyl acetate and vinyl propionate, Vinyl ethers such as butyl vinyl ether and cetyl vinyl ether, esters of acrylic acid or methacrylic acid such as methyl methacrylate, methyl acrylate, ethyl methacrylate and phenyl methacrylate, aromatic vinyl compounds such as styrene and α-mephilstyrene; Halogenated vinyl compounds other than vinyl chloride such as vinylidene chloride and vinyl fluoride, and N-substituted maleimides such as N-phenyl maleimide and N-cyclohexane maleimide, and the like, and the like. Used in combination of more than one kind.

Polymers other than the vinyl chloride-based polymers used in the production of the graft copolymers described above may be those capable of graft polymerization of vinyl chloride, and for example, ethylene / vinyl acetate copolymers and ethylene / vinyl acetate / carbon monoxide copolymers. Copolymer, ethylene / ethyl acrylate copolymer, ethylene / ethyl acrylate / carbon monoxide copolymer, ethylene / methyl methacrylate copolymer, ethylene / propylene copolymer, acrylonitrile / butadiene copolymer, polyurethane, chlorinated polyethylene, chlorinated polypropylene These etc. are mentioned, These are used by only one type or the combination of two or more types.

The vinyl chloride resin described above may be obtained by any polymerization method such as a suspension polymerization method, suspension polymerization method, solution polymerization method, or bulk polymerization method.

The antimicrobial inorganic compound as the second component constituting the antimicrobial resin composition of the present invention contains silver and / or zinc element as an antimicrobial active ingredient, and is an essential component for imparting antimicrobial performance to the resin composition of the present invention. Alternatively, the zinc compound is preferably supported on an inorganic fine powder carrier. Specifically, a carrier made of zirconium phosphate, titanium phosphate, calcium phosphate, aluminum silicate, or the like, zinc oxide and general formula Ca _1-x Zn _x O or Mg _1-x Zn _x O (x is 0.001 ≦ x ≦ 0.5 Oxide) and the like. In the present invention, one or two or more kinds of these inorganic compounds can be selected and used.

Among the inorganic antimicrobial agents described above, in order to solve the problems of the height and the conventional problems of antimicrobial performance, zirconium phosphate substituted with silver, general formula Ca _1-x Zn _x O or Mg _1-x Zn _x O (x is 0.001≤ more preferably a composite oxide and zinc oxide.

In metal-in and / or zinc in the inorganic compound comprising, as an active ingredient, the composition of what the zirconium phosphate or phosphate titanium by gas is ₃ · nH ₂ O the general formula ^{_{M 1 u A v Zr (PO}} 4) , and M ¹ _u A _v Ti ₂ (PO ₄ ) ₃ nH ₂ O, wherein M ¹ represents a cation selected from silver ions and zinc ions (the ionic value is p), and A represents an alkali metal ion, Cation selected from alkaline earth metal ions, hydrogen ions and ammonium ions (where ionic value is q), u and v are integers satisfying pu + qv = 1, respectively, and n is greater than 0 or 6 Is an integer that does not. More specifically, although what is represented by the following formula is mentioned, it is not limited to these.

Silver or zinc-containing antimicrobial compounds based on these zirconium phosphates or titanium phosphates are alkali metal ions and alkaline earths in a wet method in which phosphate ions and tetravalent ions of zirconium or titanium are reacted in water under normal pressure or pressure. Metal ions, ammonium ions, hydrogen ions and the like can be obtained by a method of replacing silver or zinc ions having antimicrobial activity with respect to zirconium phosphate or titanium phosphate synthesized. In addition, in order to increase the chemical and physical stability, it is preferable to fire the above reaction product at a temperature of 500 to 1000 ° C.

Specific examples of the calcium phosphate gas include hydroxyapatite or tricalcium phosphate gas, specifically, Ag _0.14 Ca _{9. 93} (PO ₄ ) ₃ (OH ₂ ) Ag _0.20 Ca _9.90 (PO ₄ ) ₆ (OH) ₂ and the like.

Further, it is used as a carrier in the aluminum silicate formula ^{_{aM 2 O · Al 2 O 3}} · bSiO 2 · nH 2 O ( wherein, M ² is silver ion or zinc ion ion exchanged with potassium ions, sodium ions, Positive ions such as calcium ions, magnesium ions, iron ions, etc. (a, b are coefficients), and these aluminosilicate compounds may contain silver ions or zinc ions by ion exchange. The content of silver ions or zinc ions in the aluminosilicate compound containing silver ions or zinc ions is preferably in the range of 0.01 to 20% by weight, more preferably in the range of 5 to 20% by weight.

In the composite zinc oxide represented by the general formula Ca _1-x Zn _x O or Mg _1-x Zn _x O, x in the formula is in the range of 0.001 ≦ x ≦ 0.5, preferably in the range of 0.01 ≦ x ≦ 0.3. More preferably, it is the number of the range of 0.05 <= x <= 0.3. If the value of x is less than 0.001, the zinc concentration due to the reaction of zinc ions with hydrogen chloride generated by pyrolysis of vinyl chloride resin when forming a film becomes too low while the concentration of zinc, which is an active ingredient of the antimicrobial action, is too low. Along with the decrease in concentration, it will not be able to exert its antimicrobial performance. Moreover, when the value of x exceeds 0.5, zinc oxide will mix in the said inorganic compound, and the transparency of a film will fall. Among these composite zinc oxides, those represented by Mg _1-x Zn _x O are suitably used in view of the antimicrobial performance of the resin composition, extrusion moldability at the time of film production, less coloring, and the value of x in that case is It is more preferable to exist in the range of 0.03-0.15.

In the present invention, only one kind of the antimicrobial inorganic compound may be used, or two or more kinds thereof may be used in combination. When two or more types are selected and mixed from an antimicrobial inorganic compound containing silver and / or zinc as an active ingredient, the total amount thereof is 0.01 to 1.00 parts by weight, preferably 0.03 to 100 parts by weight of the vinyl chloride resin. It is in the range of 0.20 part by weight. If the added amount is less than 0.01 part by weight, the antimicrobial performance cannot be sufficiently exhibited. On the contrary, if the amount exceeds 1.00 part by weight, the resin film is colored or discolored with time, which is not preferable.

Further examples of specific combinations Ca _1-x Zn _x O or _{Mg 1-x Zn x O (} x in case of using the inorganic compounds in combination of two or more in the present invention is a number that ranges from 0.001≤x≤0.5 It is preferable to use in combination with the compound which uses as a gas the zirconium phosphate containing the complex oxide of zinc represented by (), and silver as an active ingredient.

In the above-mentioned antimicrobial inorganic compound, when the metal active ingredient is silver only, the addition amount thereof is preferably 0.01 to 0.20 parts by weight, more preferably 0.05 to 0.14 parts by weight based on 100 parts by weight of the vinyl chloride resin. In addition, when the metal active ingredient is only zinc, its amount is preferably 0.10 to 1.00 part by weight, more preferably 0.30 to 0.80 part by weight based on 100 parts by weight of the vinyl chloride resin.

In the antimicrobial vinyl chloride resin composition of the present invention, the nonionic surfactant used as the third component is selected from glycerin fatty esters and polyoxy ethylene alkyl ethers. Among the nonionic surfactants described above, glycerin fatty acid esters include glycerin monooleate, diglycerol monooleate and diglycerol oleate. Polyoxyethylene lauryl ether, polyoxyethylene myristyl ether, polyoxyethylene palmityl ether, polyoxyethylene stearyl ether, etc. are mentioned as polyoxyethylene alkyl ether. Ether of the saturated alcohol of 12-18 carbon atoms and polyoxyethylene glycol in 1 molecule is preferable, and among these, polyoxyethylene lauryl ether is more preferable. One type of these nonionic surfactants may be used, or two or more types thereof may be used in combination. The addition amount is 0.5-5.0 weight part with respect to 100 weight part of vinyl chloride resins, Preferably it is 0.8-4.0 weight part, More preferably, it is 1.0-3.0 weight part. If this addition amount is less than 0.5 weight part, antimicrobial performance will not fully be exhibited, and when it exceeds 5.0 weight part, a resin film may be colored or discolor over time, and antimicrobial performance may fall. Moreover, depending on the kind of nonionic surfactant, when used in large quantities, it may fold on the surface of the resin film obtained by shape | molding a resin composition, impairing the efficiency of the packaging operation using this film, and In the molding step, quality problems such as volatilization and vaporization of a part thereof occur.

Among the nonionic surfactants described above, the monoglycerin fatty acid ester itself has an antibacterial action, and also has a function as an antifogging agent of the resin film. It is thought that only one hydroxyl group out of the three hydroxyl groups of glycerin is esterified with a fatty acid group, and the remaining two hydroxyl groups promote the ionization of the metal element of the antimicrobial compound. Specific compounds of the monoglycerine fatty acid esters include monoglycerine caprylic acid ester, monoglycerine caprylic acid ester, monoglycerine lauric acid ester, monoglycerine myristic acid ester, monoglycerine palmitic acid ester, monoglycerine oleic acid ester, monoglycerine And esters with 8 to 18 saturated fatty acids or unsaturated fatty acids in one molecule such as stearic acid ester. Among these, monoglycerol oleic acid ester, monoglycerine millic acid ester and monoglycerine palmitic acid ester It is preferable from the standpoint of antibacterial performance, bleeding volatility from the film surface and odor.

These monoglycerol fatty acid esters can be produced by esterification reaction of glycerin with fatty acids or transesterification reaction of glycerin with fats and oils. The reaction product obtained in such a reaction is usually a mixture of monoglycerides, diglycerides, triglycerides and unreacted glycerin, and monoglycerides are obtained by distilling this mixture by molecular distillation.

In addition, a surfactant other than it, for example, sorbitan fatty acid ester, may be added in order to impart good automatic packaging suitability to the molded film in combination with the above nonionic surfactant. Examples of the sorbitan fatty acid esters include sorbitan laurate, sorbitan oleate, sorbitan palmitate, sorbitan stearate, and sobitan linoleate. Sorbitan esters of saturated fatty acids or unsaturated fatty acids having 12 to 18 carbon atoms in one molecule are mentioned, and among these, sorbitanate and sorbitan laurate are preferable.

The addition amount of this sorbitan fatty acid ester is good in the range of 0.3-1.0 weight part with respect to 100 weight part of vinyl chloride resin, Preferably it is 0.5-0.95 weight part, More preferably, it is good in the range of 0.6-0.8 weight part. If this addition amount is less than 0.3 weight part, automatic packaging suitability will not improve, but when it exceeds 1.0 weight part, the antimicrobial property of a resin composition will fall.

In addition, the above-mentioned glycerin fatty ester, polyoxyethylene alkyl ether and sorbitan fatty acid ester are suitable for the prevention of coloration of the molded article and stabilization of the antimicrobial performance of which the HLB value thereof is 6.0 or less or 8.0 or more, but is outside the above range. Since non-ionic surfactants tend to promote the ionization of silver or zinc in the antimicrobial inorganic compounds as the second component in the antimicrobial vinyl chloride resin composition, such nonionic surfactants can be used to exhibit the antimicrobial performance of the resin film within a short time. It is valid to use. Non-ionic surfactants having an HLB value outside the above range contain the above-mentioned sorbitan monolaurate, but when added thereto, the added amount thereof is 1.0 parts by weight or less based on 100 parts by weight of vinyl chloride resin in the sense of suppressing excessive ionization. It is necessary to do

The plasticizer as the fourth component used in the resin composition of the present invention (A) an adipic acid alkyl ester plasticizer having an alkyl group having 8 or more carbon atoms, (B) an aliphatic alcohol having 10 or less carbon atoms in one molecule It is preferable to use the plasticizer which belongs to at least 2 group from the 3 groups of the mixed adipic acid ester plasticizer obtained by reaction of two or more types and adipic acid, and (C) epoxidized vegetable oil type plasticizer suitably. Especially, as the combination, the 3 group of (A) and (B) and (C), the 2 group of (A) and (C), or the combination of the 2 group of (B) and (C) is preferable.

Specific examples of the plasticizers of the (A) group include diotanadirate, i.e., alcohols having 8 carbon atoms in one molecule, such as diesters of n-octane and 2-ethyl hexane alcohol and adipic acid, diisononyl adipate, and di Isodecyl adipate etc. are mentioned, Among these, diisononyl adipate is preferable. Plasticizers of group (B) are n-hexyl alcohol (C ₆ ), n-heptyl alcohol (C ₇ ), n-octyl alcohol (C ₈ ), n-nonyl alcohol (C ₉ ) and n-decyl alcohol (C ₁₀ Mixed esters obtained in the reaction of two or more aliphatic alcohols selected from a) and adipic acid, and specific examples thereof include C _6,8 adipate, C _8,10 adipate, C _7,9 adipate, and C _{6,8 And 10} adipates, and among these, C _6,8,10 adipates are preferred. Specific examples of the plasticizer of group (C) include epoxidized soybean oil, epoxidized castor oil, epoxidized amide oil, epoxidized safloor oil, and the like. Among these, epoxidized soybean oil is preferable.

It is preferable to use these (A), (B), and (C) group plasticizers in the combination mentioned above, and if the usage-amount is in the range of 20-60 weight part in total amount with respect to 100 weight part of vinyl chloride-type resins, Preferably it is good to set it in 25-50 weight part. If the amount of the plasticizer is less than 20 parts by weight, the processability of the resin composition and the properties of the obtained film are deteriorated, which is unsuitable for practical use. If the amount of the plasticizer exceeds 60 parts by weight, the antibacterial performance is lowered, which is not preferable. In addition, the amount of plasticizer of group (C) is preferably used in an amount of 10 to 30 parts by weight within the above range, and the amount of plasticizer of group (A) and / or (B) is used for the plasticizer of group (C). What is necessary is just to make the difference between the usage-amount and the total plasticizer amount. As a plasticizer which can be used other than the above, the polyester plasticizer of the molecular weight 1000-3000 is mentioned.

The calcium / zinc stabilizer as the fifth component is composed mainly of calcium fatty acid salts and zinc fatty acid salts, and specific examples of the fatty acids constituting the salts include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and lycid. Noluic acid, 2-ethylhexanoic acid, isodecanoic acid, neodecanoic acid, etc. are mentioned, In the calcium salt, calcium benzoate is mentioned besides these salts. In the present invention, at least one selected from the group of the above-mentioned fatty acid calcium and fatty acid zinc is selected and used in combination.

Moreover, it is preferable to comprise the ratio of fatty acid calcium and fatty acid zinc at the weight ratio which makes 40%-70% of fatty acid calcium, and 30%-60% of fatty acid zinc, and the addition amount of an antimicrobial inorganic compound in the resin composition of this invention. In many cases, increasing the composition ratio of the fatty acid zinc is effective in preventing the coloring of the resin composition and imparting activity during molding processing. When the composition ratio of the fatty acid zinc is 30% by weight, coloring becomes easy and the activity of the resin composition during molding is insufficient. On the other hand, when the composition ratio exceeds 60 weight%, the balance with the zinc component of an antimicrobial inorganic compound may fall, and it may become difficult to obtain stable antimicrobial performance.

In addition, it is arbitrary to use the above-mentioned calcium / zinc-based stabilizer in combination with other stabilizers, and as such a usable stabilizer, organic phosphates such as trisnonyl phenyl phosphate, 2,2'-methylene bis (4 Phenols such as -metal-6-t-butylphenol), alcohols such as tridecyl alcoholdipropylene glycol, polypropylene glycol, synthetic paraffins, solvents such as synthetic isoparaffin, petroleum hydrocarbons, stearyl yl yl ylmyl and palmityl benzoyl methane And beta -diketone compounds such as dehydroacetic acid and the like can be exemplified.

The amount of the stabilizer as the fifth component is in the range of 0.1 to 2.5 parts by weight, preferably in the range of 0.5 to 2.0 parts by weight, and more preferably in the range of 0.8 to 1.5 parts by weight with respect to 100 parts by weight of the vinyl chloride resin. to be. If this addition amount is less than 0.1 weight part, the thermal stability of a resin composition will become inadequate and it cannot shape | mold into a film. On the other hand, when this addition amount exceeds 2.5 parts by weight, not only the transparency of the film is lowered but also the antimicrobial performance of the antimicrobial resin composition may be unstable, which is not preferable.

Various well-known additives can be mix | blended with the resin composition of this invention other than said 1st component-5th component. Such additives include lubricants such as higher fatty acids such as stearic acid, isostearic acid and 12-hydroxystearic acid, polyethylene, synthetic paraffin, mixed esters of adipic acid / high fatty acid of pentyl erythritol, polyglycerin fatty acid esters, Nonionic surfactants, hydrotalcite compounds and the like other than the third component such as sorbitan fatty acid esters, polyoxyethylene aliphatic alcohol acetates, and polyoxyethylene sorbitan fatty acid esters can be used. These addition amounts are used in the range of 0.1-5.0 weight part with respect to 100 weight part of vinyl chloride-type resins, respectively.

The antimicrobial vinyl chloride resin composition of the present invention comprising the above first to fifth components has a water content of 0.005 to 0.300% by weight, preferably 0.01 to 0.20% by weight, more preferably 0.030 to It is preferable to exist in the range of 0.150 weight%. The water content in the resin composition is preferably adjusted in accordance with the molding conditions so that the water content of the film obtained by molding the resin composition within the above range is 0.001% by weight to 0.100% by weight. If the moisture content is in the above range, the ionization of silver and / or zinc does not affect the quality of the antimicrobial effect, the extrudability, and the appearance of the molded product.

The greatest effect of the present invention is to stably and stably exhibit the antibacterial performance of the resin composition obtained by the antimicrobial inorganic compound containing silver and / or zinc as an active ingredient for a long time, and at the same time, the metal component is oxidized so that the resin composition It is possible to prevent coloration or discoloration of the metal, but when the moisture content exceeds 0.300% by weight, ionization of the metal component is promoted, antimicrobial performance is stabilized for a long time and does not become constant and the metal component is oxidized. It becomes easy to become and causes coloring and discoloration. If the amount is less than 0.005% by weight, ionization of the metal element is insufficient, and there is a concern that the antibacterial performance in the initial stage of the use of the molded product is particularly low. Therefore, when the water content of the resin composition is in the above range, ionization of the metal element is appropriate, and molded articles, particularly wrap films, formed using the resin composition can exhibit stable antibacterial performance from the beginning of use. The present inventors have experimentally found that the above-mentioned effect by this specific water content is exhibited together with the effect of the nonionic surfactant which is an essential component.

It is preferable that the said water content rate is measured and calculated | required by what is called a Can fischer method (JIS K 0113). The outline of the measuring method is as follows. First, 1 g of the resin composition powder as a sample is accurately weighed on a scale in a clean and dried powder collector. After being weighed and weighed, the sample is quickly fed from the powder collector into the sample boat of the water vaporizer. At that time, the sample boat is burned in an empty state without a sample for 1 minute in the outer cylinder portion of the heating furnace and then for one minute in the heating furnace, and then cooled to 50 ° C. or lower in the outer cylinder portion of the heating furnace. The sample boat which the sample listened to is sent to a heating furnace, heated to 180 degreeC, vaporized water is sent into a suitable cell using nitrogen gas as a carrier, and the moisture content is measured. In that case, a titration cell is made anhydrous by the following method. The water in the titration cell is gently shaken and moved to be absorbed by the electrolyte solution (liquid iodide ion, sulfur dioxide, and pyridine dissolved in methanol) without flowing the carrier gas, and the titration cell is returned to the stirring portion to stir and blank is removed. . This operation is repeated 2 to 3 times, so that the titration rate (background) at the time of titration at the end point is set to less than 0.2 µg / sec.

In addition, as a method of making the water content in a resin composition into the said specific range, what is necessary is just to make the sum total of the water content in each component added to be the water content rate in the said range, or the degassing process in the preparation method of the composition described below. It is achieved by appropriately carrying out, but more specifically, it is relatively easy to adjust the water content of the vinyl chloride resin composition of the present invention by adjusting the water content of the calcium / zinc-based stabilizer and can be used as a highly accurate method. The adjustment method of the water content in a bistable agent is performed by controlling the amount of water removal in the dehydration reaction at the time of synthesize | combining the calcium salt and zinc salt of the higher fatty acid which are the main components of a stabilizer.

The vinyl chloride resin composition according to the present invention uses a mixing device such as a Henschel mixer, a ribbon blender, a naphtha mixer, or the like, and a plasticizer or the like is added to the vinyl chloride resin at a temperature of 90 to 140 ° C. due to heat generation during mixing. It can obtain by the conventionally well-known dry blend method which makes it absorb.

In this invention, it is preferable to add the antimicrobial inorganic compound as a 2nd component with respect to the basic mixture which consists of components other than that previously prepared by the dry blending method, for example, to mix and disperse | distribute uniformly. This method is effective to prevent the following closure. When an antimicrobial inorganic compound is initially added at the time of dry blending, the closed end at the time of extrusion molding is encouraged. This is because plasticizers, stabilizers and the like are also absorbed in the antimicrobial inorganic compound particles, or the surface thereof is covered so that the active effect is excessively large and stable kneading characteristics are not obtained. In addition, the molded film is easily colored, and the degree of coloring is also strong. As described above, magnesium ions and calcium ions are easily released from magnesium oxide or calcium oxide due to the effects of plasticizers absorbed onto or covering the surface of the antimicrobial inorganic compound particles, and these ions are vinyl chloride during extrusion molding. In order to capture the chlorine in the hydrogen chloride generated by the thermal decomposition of the system resin, it appears as the color of the compound.

And mixing of an antimicrobial inorganic compound can be performed by injecting an antimicrobial inorganic compound into a mixer, and disperse | distributing and mixing uniformly, when cooling a dry blended base mixture.

The vinyl chloride resin composition thus obtained can be formed into a film by a melt extrusion method, but a conventionally known method such as a T-die method or an inflation method may be employed.

Although the thickness of the film obtained by the present invention depends on the use, a range of 5 to 100 µm is preferable, and if the thickness is less than 5 µm, when the film is stretched when used, holes are formed in the portion where the antimicrobial particles are present. It is liable to be damaged or breakage, and the heat resistance at the time of heating with a microwave oven after food packaging, etc. is brought down, and a practical closure occurs. On the other hand, if the thickness of the film exceeds 100 µm, the number of antimicrobial particles to be exposed on at least a portion of the film surface becomes smaller than the added amount, so that sufficient antimicrobial performance cannot be exhibited and the mechanical properties of the film are not suitable for packaging. . For this reason, the film thickness is preferably in the range of 5 to 50 µm, more preferably 5 to 30 µm, in terms of antibacterial performance and packaging suitability.

Hereinafter, the present invention will be described in more detail with reference to experimental examples, but the present invention is not limited to these experimental examples. Test items and test methods performed on the antimicrobial vinyl chloride resin composition and the resin film obtained by molding the same in the following Experimental Examples are as follows.

1. Plate Outlet Test

The resin composition was kneaded for 5 minutes using two 6-inch rolls with a roll temperature of 150 ° C, and the contamination of the surface of the roll by the antimicrobial inorganic compound was visually observed, and the results were expressed by the numerical values of 1 to 5 steps. And the smaller the numerical value, the smaller the plate outer part is, and 3 or more are rejected.

2. Water content measurement

It measured by the Karl Fischer method (JIS K 0113) using the apparatus shown below.

(Device)

Whole quantity titration type moisture measuring apparatus CA-06 (Mitsubishi Chemical Corporation, brand name)

Moisture Vaporizer VA-06 (Mitsubishi Chemical Corporation, brand name)

Karl Fischer reagent Acromicron AX (manufactured by Mitsubishi Chemical Corporation, trade name)

Acami micro CUX (Mitsubishi Chemical Corporation, brand name)

3a. Coloring test I

The resin composition was kneaded for 2 minutes using two 6-inch rolls having a roll temperature of 150 ° C., and then pressed at 190 ° C. to prepare a sheet having a thickness of 50 μm. The color tone of the obtained sheet | seat was measured with the color difference meter (made by Sugashion Co., Ltd.). In addition, when a value or b value is 10% or more, a resin composition is unsuitable as a raw material of a packaging film.

3b. Coloring test II

The resin composition was kneaded for 2 minutes using two 6-inch rolls having a roll temperature of 150 ° C., and then pressed at 165 ° C. to prepare a sheet having a thickness of 50 μm. The obtained sheet was kept in a UV tester, and the change in color tone over time was measured by a color tone colorimeter.

The hue is assumed to be no quality problem as long as the a value is 2.5% and the b value is within 2.5% of the initial value.

(Device)

UV tester: made by Suga Shikiki

Long type built-in tester STANDARD UVLONG-LIFE FADE MATER

Hue color difference meter

4a. Antimicrobial Performance Test I

The test piece prepared in the same manner as in the coloring test I was used for the antibacterial performance test against E. coli. The test was carried out by the "film adhesion method", and the reduction rate of the viable cell count when the test results of the resin composition of each test example were compared with the test results of the control sample prepared in the same manner except that no antibacterial agent was added. (%) Is indicated. In addition, the reduction rate of less than 99.8% is insufficient antibacterial performance.

4b. Antimicrobial Performance Test II

Regarding the resin composition of a typical formulation, a film having a thickness of 8 µm by the inflation method and a film having a thickness of 13 µm by the T-die method was prepared, and antibacterial performance test against Escherichia coli, Staphylococcus aureus, Salmonella and enteritis Vibrio was performed. Was carried out. In addition, there is also an experimental example that carried out only the antibacterial activity against E. coli.

In the test, the number of viable cells after storage at 35 ° C. for 24 hours was measured by the “film adhesion method”. Three samples were used to evaluate the deviation of n = 3 (reproducibility of antibacterial performance). And when a bacterium was not detected on the sample surface, the result was shown as "10". Test conditions are as follows.

(1) Escherichia coli IFO 3972 (E. coli)

Staphylococcus aureus IFO 12732 (Staphylococcus aureus)

Salmonella enteritidis IFO 3313

Vibrio parahaemolyticus RIMD 2210100 (enteritis vibrio)

(2) badge

NA badge: Normal agar badge [manufactured by Aesop Chemical Co., Ltd.]

NB medium: Normal non-ion medium containing 0.2% meat concentrate [Aei Kagaku Co., Ltd.]

1/500 NB medium: The pH is adjusted to 7.0 ± 0.2 by diluting NB medium 500 times with purified water.

1/200 NB medium: pH adjusted to 7.0 ± 0.2 by diluting NB medium 200 times with purified water.

SCDLP Medium: SCDLP Medium [manufactured by Aesop Chemical Co., Ltd.]

SA badge: Standard agar badge [manufactured by Aesop Chemical Co., Ltd.]

In addition, 3% of salt was added to the medium used for enteritis vibrio bacteria.

(3) Preparation of bacterial liquid

Test bacteria incubated in NA medium at 37 ± 1 ° C. for 16 to 24 hours were inoculated again in NA medium and incubated at 37 ± 1 ° C. for 16 to 24 hours. The cultured bacteria were uniformly dispersed in E. coli, Staphylococcus aureus and Salmonella in 1/500 NB medium, and enteritis vibrio in 1/200 NB medium, respectively, to adjust the number of bacteria per 1 ml to 105 to 106.

(4) Preparation of Sample

The sample was cut into the size of about 5 cm x 5 cm, and the sample was lightly wiped with the cotton wool which infiltrated 99.5% ethanol.

(5) Test operation

0.5 ml of bacterial solution was added dropwise to each of three samples, and a polyethylene film was put thereon to make a close contact. These were stored under conditions of 35 ± 1 ° C. and relative humidity of 90% or more. In addition, plasticshall was used as a control sample and tested in the same manner.

(6) livestock count

After 24 hours of storage, 10 ml of SCDLP medium was used to wash live bacteria from the sample, and the number of viable bacteria in the washed solution was measured by agar plate culture method (35 ° C., 48 hours incubation) using SA medium. The viable cell count of sugar was calculated.

Experimental Examples 1 to 31

In each experiment, 100 parts by weight of homopolymerized polyvinyl chloride resin (average degree of polymerization 1300), the same as below, three kinds of plasticizers, 25 parts of diisononyl adipate and 10 parts of C _6,8,10 mixed alkyl adipate And 13 parts of epoxidized soybean oil, 1.0 part of calcium / zinc stabilizer, 0.3 part of stearic acid, 0.5 part of polyglycerin fatty acid ester and 0.5 part of sorbitan fatty acid ester, and one or two types of monoglycerin fatty acids selected from ④ and ⑤ below. The predetermined amount of ester was thrown into 20 liter Henschel mixer, and it stirred and mixed, and mixing and stirring were stopped when the mixing temperature rose to 115-120 degreeC, and the basic mixture was obtained.

Then, the basic mixture is immediately transferred to a 20-liter cooling mixer equipped with a cooling device, and a predetermined amount of one or two or more kinds of antimicrobial inorganic compounds (antibacterial agents) selected from the following ① to ③ are respectively added to the mixture and stirred. The mixture was cooled to complete the stirring at the time when the resin temperature was lowered to 70 to 80 ° C to obtain a resin composition.

Antimicrobial inorganic compound ① ... · Ag _0.05 H _0.65 Na _0.30 Zr ₂ (PO ₄ ) ₃

Antimicrobial inorganic compounds ② ... Ag _0.30 H _0.45 Na _0.25 Zr ₂ (PO ₄ ) ₃

Antimicrobial inorganic compound ③ ... Ag _0.03 (NH ₄ ) Zr ₂ (PO ₄ ) ₃

Monoglycerin Fatty Acid Ester ④ ·· Monoglycerine Oleic Acid Ester

Monoglycerin Fatty Acid Ester ⑤ Monoglycerin Palmitate

Tables 1a to 1e below show the kinds of the antimicrobial inorganic compounds and the monoglycerin fatty acid esters in Experimental Examples 1 to 31, the respective compounding amounts, the plate out test, the coloring test I and the antimicrobial test I. Tables 2a to 2d show the results of the antimicrobial test II against Escherichia coli, Staphylococcus aureus, Salmonella and Enteritis Vibrio in some experimental examples together with the thicknesses used in the experiments for each type of microorganism.

Experimental Examples 32-172

In each experiment example, the vinyl chloride resin composition was prepared as follows. First, (a) diisononyl adipate (hereinafter, abbreviated as DINA) of the amount shown in Tables 3a to 3o as a plasticizer with respect to 100 parts of homopolymerized polyvinyl chloride resin having an average degree of synthesis of 1300, (B) C _{6 3 types of, 8,10} adipate (hereinafter abbreviated as C _6,8,10 A) and (c) epoxidized soybean oil (hereinafter abbreviated as ESO), 1.0 part of Ca-zn-based stabilizer, Tables 3a to 3o Two or three kinds of diglycerin monooleate (HLB value: 4.3), polyoxyethylene lauryl ether (HLB value: 12.0) and sorbitan monolaurate (HLB value: 7.6) in the amounts indicated in 0.4 part of nonionic surfactant and isostearic acid were added, it was put into a 20-liter Henschel mixer, stirred and mixed, and mixing and stirring were stopped at the time when the mixing temperature rose to 115-120 degreeC, and the basic mixture was obtained. .

Next, this basic mixture is transferred to a 20 liter cooling mixer equipped with a cooling device, and one or two or more types of antimicrobial inorganic compounds (antibacterial agents) in amounts shown in Tables 3a to 3o selected from the following ①-③. Was added, and the mixture was cooled by mixing and stirring to stop the stirring at the time when the resin temperature was lowered to 70 ° C to 80 ° C to obtain an antimicrobial resin composition.

Antimicrobial Inorganic Compounds ① ... Ag _0.20 H _0.75 Na _0.05 Zr ₂ (PO ₄ ) ₃

Antimicrobial inorganic compound ② ... Mg _0.9 Zn _0.1 O

Antimicrobial inorganic compound ③ ··· ZnO

Thus, about the antimicrobial resin composition obtained by the mixing | blending ratio shown to Table 3a-Table 3o, the measurement of water content rate, coloring test II, and antimicrobial performance test I were performed, and the result was shown to Table 3a-Table 3o. In addition, some of these antimicrobial resin compositions were selected to carry out antimicrobial performance test II, and the results are shown in Tables 4a to 4d for each type of microorganism.

TABLE 1a

TABLE 1b

TABLE 1c

TABLE 1d

TABLE 1e

TABLE 2a

TABLE 2b

TABLE 2c

Table 2d

TABLE 3a

TABLE 3b

TABLE 3c

Table 3d

Table 3e

Table 3f

Table 3g

Table 3h

TABLE 3i

TABLE 3j

Table 3k

TABLE 3L

[Table 3m]

TABLE 3n

Table 3o

TABLE 4a

TABLE 4b

TABLE 4c

Table 4d

The present invention solves the above-mentioned problems and exhibits excellent antimicrobial performance which is stable and stable with respect to the entire surface of the film over a long period of time, and is suitable as a raw material of an antimicrobial vinyl chloride resin which does not cause discoloration or coloring. It is an object to provide a composition.

Claims (7)

(1) 100 parts by weight of vinyl chloride resin, (2) 0.01 to 1.00 parts by weight of an antimicrobial inorganic compound selected from an inorganic silver compound and an inorganic zinc compound, (3) 0.1 to 5.0 parts by weight of a nonionic surfactant selected from glycerin fatty acid esters and polyoxyethylene alkyl ethers, (4) 20 to 60 parts by weight of plasticizer and (5) An antibacterial vinyl chloride resin composition comprising 0.1 to 2.5 parts by weight of a calcium / zinc stabilizer. The antimicrobial vinyl chloride resin composition according to claim 1, wherein the vinyl chloride resin is a homopolymer of vinyl chloride having an average degree of polymerization of 1,000 to 1,300. The method of claim 1, wherein the antimicrobial inorganic compound is zirconium phosphate substituted with silver, general formula Ca _1-x Zn _x O or Mg _1-x Zn _x O (x is a number in the range of 0.001≤x≤0.5) An antimicrobial vinyl chloride resin composition selected from composite oxides and zinc oxides. The antimicrobial vinyl chloride resin composition according to claim 1, wherein the nonionic surfactant is a glycerin fatty acid ester selected from monoglycerine oleic acid ester, monoglycerine myristic acid ester, and monoglycerine palmitic acid ester. 2. The aplasticizer according to claim 1, wherein the plasticizer is (a) an aflic acid alkyl ester plasticizer having an alkyl group having 8 or more carbon atoms, (b) two or more aliphatic alcohols having 10 or less carbon atoms in one molecule, adipic acid, An antimicrobial vinyl chloride resin composition selected from mixed adipic acid ester plasticizers and (C) epoxidized vegetable oil based plasticizers obtained in the reaction. The antimicrobial vinyl chloride resin composition according to claim 1, wherein the calcium / zinc stabilizer is composed of fatty acid calcium and fatty acid zinc, and the weight ratio is 30% to 60% of fatty acid zinc relative to 40% to 70% of fatty acid calcium. The antimicrobial vinyl chloride resin composition according to claim 1, wherein the nonionic surfactant is a combination of 0.1 to 5.0 parts by weight of a nonionic surfactant selected from glycerin fatty acid ester and polyoxy ethylene alkyl ether and 0.3 to 1.0 part by weight of sorbitan fatty acid ester. .