JP3509046B2 - Vinyl chloride sheet with moisture resistance - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] Vinyl chloride resin is excellent in balance of physical properties and cost performance among various resins. The present invention relates to packaging materials for foods, pharmaceuticals and the like. 2. Description of the Related Art Halogen-containing resins such as vinyl chloride resins, when subjected to heat molding, are deteriorated in physical properties and color tone mainly due to thermal decomposition mainly due to dehydrohalogenation, resulting in extremely poor quality. Invite profit. To avoid such disadvantages,
It is necessary to add one or several kinds of heat stabilizers at the time of processing the sheet to suppress deterioration in the processing step. For such a purpose, a heat stabilizer in which an organic phosphite, a phenolic compound, or an epoxy compound is added to a combination of metal compounds such as lead, cadmium, barium, and zinc has been used. However, since metals such as cadmium, lead, and barium are highly toxic and are likely to cause problems during use or disposal, etc., cadmium, lead, and barium-based metal compound stabilizers are used without using calcium-zinc-based metals. A heat stabilizer in which an organic phosphite, a phenolic compound, and an epoxy compound are added to a combination of compounds is used. However, cadmium, lead, and barium-based metal compound stabilizers have been used to prevent thermal decomposition caused by dehydrohalogenation, the resulting heat resistance, and the ability to prevent initial coloration (a phenomenon in which color is initially applied to the heat history during processing). There is a disadvantage that it is inferior to the contained stabilizer. In order to solve these drawbacks, β-diketone compounds represented by the following general formula have been used as heat stabilizers, particularly as an initial coloring inhibitor, as calcium-zinc metal compound stabilizers, and their effects have been reduced. (JP-A-52-47)
948). R-CO-CHX-CO-R (wherein, X represents a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, and R represents an alkyl group or an aryl group) However, in recent years, the size and speed of calendar equipment have been increased. Due to the combination of calcium-zinc-based metal compound stabilizers and other organic phosphites, epoxy compound diketone compound stabilization aid alone, thermal stability is insufficient, further heat resistance persistence, and initial coloring prevention properties It has been demanded. [0004] Calcium compounds are used because they have the effect of not decomposing thermally, and zinc compounds are used because they have the effect of being difficult to discolor at the initial stage.
However, calcium compounds have a problem that initial coloring is easy, and zinc compounds must be used together to prevent initial coloring. When zinc compounds are contained, they are called zinc burning (zinc burning) during sheet processing. There has been a problem that rapid thermal decomposition occurs, which causes decomposition and blackening within a short period of time, resulting in poor heat resistance. The problems of zinc burning are polyhydric alcohols such as mannitol, sorbitol, pentaerythritol and dipentaerythritol, hydrotalcite, zeolites, oxides (calcium and magnesium), and hydroxides (calcium and magnesium).
The problem can be solved by adding a co-stabilizer represented by an inorganic salt such as However, the polyhydric alcohol substance has a relatively short stabilization time, and a zinc compound to be added for preventing initial coloring is taken into its structure, and the initial coloring tends to be poor. [0005] Hydrotalcite compounds having a specific crystal structure are used as stabilizers for halogenated resins. The hydrotalcite compound has an effect of capturing and stabilizing and neutralizing hydrogen chloride generated by the thermal decomposition of the vinyl chloride resin, and has been used in combination with a calcium-zinc-based stabilizer to enhance the effect. The vinyl chloride resin sheet is produced by calender rolling, and a higher fatty acid compound such as stearic acid or lauric acid is mainly used as a lubricant to be added. However, in the case of an acid lubricant having a carboxylic acid group, the hydrotalcite compound and the carboxylic acid react with each other, and the resulting magnesium soap compound is colored red. Was.
On the other hand, in the recent packaging, especially pharmaceuticals and food packaging, the contents are sensitive to the environment. In particular, in the case of pharmaceuticals and the like, the performance of the pharmaceuticals may be degraded by moisture, so that moisture proofing is strongly required. SUMMARY OF THE INVENTION The present invention is to provide a vinyl chloride sheet having moisture proof properties, excellent heat resistance during sheet processing, and free from deterioration of initial coloring. According to the present invention, the vinyl chloride resin layer (A) comprises 0.01 to 2 parts by weight of a calcium compound and 0.1 to 2 parts by weight of a zinc compound based on 100 parts by weight of the vinyl chloride resin. 01-2 parts by weight, the general formula _{[Mg W · Al X · (OH} ) Y ·
(CO ₃ ) _Z ] mH ₂ O (W, X, Y and Z are 2W + 3X = Y
+ 2Z is a positive number, W is 2 ≦ W ≦ 6, and m is a positive number, 2 ≦ m ≦ 4).
0.01 to 5 parts by weight of the composition, or 100 parts by weight of vinyl chloride resin, calcium compound 0.01 to
2 parts by weight, compounds 0.01 to 2 parts by weight of zinc, the formula _{[Mg W · Al X · (OH} ) Y · (CO 3) Z ] mH ₂ O (W,
X, Y and Z are positive numbers satisfying 2W + 3X = Y + 2Z and W
Is 2 ≦ W ≦ 6, m is a positive number and 2 ≦ m ≦ 4) 0.01 to 5 parts by weight of a hydrotalcite compound, 0.1 to 5 parts by weight of epoxidized vegetable oil, β-diketone compound 0 .0
A resin composition comprising 1 to 1 part by weight and 0.01 to 2 parts by weight of an ester compound, wherein the resin layer (A) has a vinylidene chloride resin layer (B) on at least one surface thereof, and further has a vinyl chloride resin layer The average degree of polymerization of the vinyl chloride resin (A) is from 500 to 1,000, and the ester compound is from 1 to 3
Is a compound consisting of monovalent glycerin and higher fatty acids.
The flexibility temperature of the vinyl chloride resin layer (A) is 50 to 80 ° C. according to the flexibility temperature test of IS K6734, the thickness of the vinyl chloride resin layer (A) is 0.02 to 1 mm, and the vinylidene chloride resin layer (B) Is a vinyl chloride sheet having a thickness of 1 to 500 μm. DETAILED DESCRIPTION OF THE INVENTION The vinyl chloride resin layer (A) of the present invention
The vinyl chloride resin used for the polymerization has an average degree of polymerization of 500 to 1
When the average degree of polymerization is less than 500, the melt viscosity becomes low, the stiffness of the sheet decreases, and the workability of the sheet such as a calendar deteriorates. Average degree of polymerization is 1000
Exceeding the melting point increases the melt viscosity and requires a high temperature during sheet processing, which hinders sheet production. The calcium compound used in the vinyl chloride resin layer (A) includes C _{8 to} C ₂₂ such as carbonate, silicate, orthophosphate, heptanoate, 2-ethylhexylate and stearate. Higher fatty acid salts of 1,2 hydroxystearate, lactate, citric acid, gluconate, sorbate, rosinate, ethyl acetoacetate, benzoate, isodecanoate, neodecanoate, naphthenic acid Salts, hydroxides and the like. The addition amount of the calcium compound is based on 100 parts by weight of the vinyl chloride resin.
0.01 to 2 parts by weight is suitable, preferably 0.05 to 1 part by weight.
Parts by weight. When the amount is less than 0.01 part by weight, zinc burning occurs and thermal stability is deteriorated. When the amount is more than 2 parts by weight, initial coloring is deteriorated. As the organic compound of zinc used in the vinyl chloride resin layer (A), there may be mentioned a higher salt of C _{8 to} C ₂₂ such as carbonate, orthophosphate, heptanoate, 2-ethylhexylate and stearate. Fatty acid salts, rosinates, dibutyldithiocarbamates, salicylates, isodecanoic acids, neodecanoates, naphthenates, and the like are included. The amount of the zinc compound to be added is suitably 0.01 to 2 parts by weight, preferably 0.05 to 2 parts by weight, per 100 parts by weight of the vinyl chloride resin.
１1 part by weight. If the amount is less than 0.01 parts by weight, the initial coloring will be poor, and if it is more than 2 parts by weight, zinc burning will occur rapidly and thermal stability will be poor. [0011] hydrotalcite compound used in the layer Vinyl chloride resin (A) has the general formula [Mg _W · Al _X · (O
H) _Y · (CO ₃ ) _Z ] mH ₂ O (W, X, Y and Z are positive numbers satisfying 2W + 3X = Y + 2Z, 2 ≦ W ≦ 6, m
Is a positive number represented by 2 ≦ m ≦ 4), but is generally magnesium hydrotalcite represented by the formula (Mg ₆ .Al _2. (OH) _16. (CO ₃ )) 2H ₂ O Compounds are used. The hydrotalcite compound may be a natural product or a synthetic product. As a synthesis method, for example,
No.-2280, No.50-3039, No.51-2912
The known method in No. 9 can be exemplified. Further, the hydrotalcites in the present invention can be used without limitation on the particle diameter, and the surface thereof may be covered with a higher fatty acid such as stearic acid, a higher fatty acid amide, a higher fatty acid ester, or a wax. The addition amount of the hydrotalcite compound is 0.01 to 5 with respect to the vinyl chloride resin.
Parts by weight, preferably 0.1 to 1 part by weight.
When the amount is less than 0.01 part by weight, no effect is recognized. When the amount is more than 5 parts by weight, the improvement in performance is small, and poor appearance due to foaming and a decrease in mechanical strength are liable to occur. An epoxidized vegetable oil can be added to the vinyl chloride resin layer (A) composition of the present invention. Examples of the epoxidized vegetable oil include epoxidized linseed oil, epoxidized soybean oil, epoxidized castor oil, epoxidized safflower oil, epoxidized linseed oil fatty acid butyl, octyl epoxy stearate, and 3- (2-xenoxy) -1. , 2
-Epoxypropane, epoxidized polybutadiene, di-2-ethylhexyl epoxyhexahydrophthalate, di-n-octyl epoxyhexahydrophthalate, bis (9,10-epoxystearyl) epoxyhexahydrophthalate, and the like. The addition amount of the epoxidized vegetable oil is preferably from 0.1 to 5 parts by weight based on 100 parts by weight of the vinyl chloride resin. If the amount is less than 0.1 part by weight, the flowability of the vinyl chloride resin is deteriorated, and the calenderability is hindered. If it is more than 5 parts by weight, the softening temperature of the sheet will decrease,
The rigidity of the sheet is reduced, which tends to cause problems in sheet processing and formability. An organic phosphite compound may be added to the vinyl chloride resin layer (A) composition. As the organic phosphite compound, for example, tris (nonylphenyl) phosphite, 2-tert-butyl-α (3-t
tert-butyl-4-hydroxyphenyl) p-cumenylbis (p-nonylphenyl) phosphite, 4'4-
Isopropylidene - diphenol alkyl (C ₁₂ ~
C ₁₅ ) phosphite. A β-diketone compound can be added to the vinyl chloride resin layer (A) composition. The amount of the β-diketone compound to be added is preferably 0.01 to 1 part by weight, based on 100 parts by weight of the vinyl chloride resin. There is no effect of increasing the dose. In addition, vinyl chloride resin layer (A)
To improve the light stability of the composition, or when used as a packaging material after sheet processing, an ultraviolet absorber may be added for the purpose of preventing light deterioration of the contents. Examples thereof include benzophenone-based, benzotriazole-based, salicylate-based, substituted acrylonitrile-based, various metal salts, or metal chelates, particularly salts of nickel or chrome, or chelates, triazine-based, piperidine-based, and the like. The composition of the vinyl chloride resin layer (A) is immersed in the vinyl chloride resin molecules to weaken the intermolecular force of the vinyl chloride resin, lower the heating temperature to increase the fluidity, and at the same time lower the secondary transition temperature. In order to allow micro-Brownian movement of the vinyl chloride resin molecular segment and obtain a flexible elastic gel, a plasticizer usually used as an additive for vinyl chloride resin can be added. Examples of the plasticizer include a phthalic acid ester compound, an aliphatic dibasic acid ester compound,
Examples thereof include a phosphate ester compound, a hydroxy polycarboxylic acid ester compound, a fatty acid ester compound, a polyhydric alcohol ester compound, and a polyester compound. The vinyl chloride resin layer (A) sheet of the present invention is produced by, for example, a calender rolling method, and an ester compound is used as a lubricant to be added. An ester compound is a compound formed by an ester bond between a long-chain fatty acid and an alcohol. Fatty acids include long-chain saturated and unsaturated monocarboxylic acids, dicarboxylic acids, and oxycarboxylic acids.Alcohols include monohydric alcohols such as butanol and octanol, and alcohols such as ethylene glycol, glycerin, pentaerythritol, and sorbitol. There are polyhydric alcohols, and many ester compounds are produced in combination with acids and alcohols. All the carboxylic acid groups of the ester compound used must react with the alcohol to form an ester bond. This is because the hydrotalcite compound reacts with the carboxylic acid, and the resulting magnesium soap compound is colored red, the effect of capturing hydrochloric acid is lost, and the initial coloring is deteriorated. For this reason, the ester compound used is preferably a trivalent ester compound of glycerin and a fatty acid, and the amount added is 0.1 to 100 parts by weight of the vinyl chloride resin.
It is preferably from 1 to 2 parts by weight. If the addition amount is less than 0.01 parts by weight, it tends to be a problem during sheet processing such as a calendar method, and if it is more than 2 parts by weight, the lubrication becomes excessive,
A sheet with good appearance cannot be obtained. Examples of the ester-based compound include glyceride stearate such as monoglyceride stearate, diglyceride stearate, and triglyceride stearate, glyceride oleate, and glyceride palmitate. The thickness of the vinyl chloride resin layer (A) is 0.02 to 1
mm is preferable, and more preferably 0.05 to 0.6 m
m. If it is thinner than 0.02 mm, sheet processing is difficult, and if it is thicker than 1 mm, molding after sheet processing is difficult. The vinyl chloride resin layer (A) of the present invention comprises
The soft temperature test shown in SK6734, that is, the soft temperature was 50 to 80 by the crashberg soft temperature measurement.
C. is preferable, and the higher the softening temperature, the lower the heat resistance, that is, the less change in appearance when heat is applied.
If the temperature is lower than 0 ° C., the heat resistance is poor, and the appearance change upon heating is large, which is likely to cause a problem at the time of molding, and more preferably 55 to 70 ° C. In addition, vinyl chloride resin layer (A)
Depending on the required sheet processability and performance, for example, a vinyl chloride-vinyl acetate copolymer, a lubricant, a crosslinking agent, a pigment, a filler, a foaming agent, an antistatic agent, an anti-fogging agent, a plate-out preventing agent, a surface treatment Agents, processing aids, release agents, reinforcing materials, and the like. The vinylidene chloride resin composition used in the vinylidene chloride resin layer (B) of the present invention is not particularly limited as long as the required moisture resistance is obtained. May be a copolymer with
Examples of the monomer to be copolymerized include vinyl chloride, vinyl acetate, acrylonitrile, methyl methacrylate, methacrylic acid, methyl acrylate, ethyl acrylate, and the like, and one or more kinds can be used. As is well known, an anti-blocking agent such as silica may be added. The method for preparing the vinylidene chloride resin layer (B) is not particularly limited as long as the required moisture-proof property can be obtained. However, the vinylidene chloride resin composition may be formed into a sheet by a hot-melt extrusion method, or the vinyl chloride resin layer (B). A) a vinylidene chloride resin composition emulsified using the base material or dissolved in a solvent such as tetrahydrofuran;
Using the vinyl chloride resin layer (A) as a base material, coating and drying,
There is a method of forming a coating film on the vinyl chloride resin layer (A). The method of laminating the vinylidene chloride resin layer (B) and the vinyl chloride resin layer (A) is not particularly limited as long as adhesion between the layers can be obtained, and examples thereof include methods such as dry lamination, extrusion lamination, hot pressing, and solution coating. Is mentioned. In addition, an adhesive such as urethane, isocyanate, acryl, polyester, or vinyl acetate may be interposed between the layers to improve the adhesion between the layers. The thickness of the vinylidene chloride resin layer (B) is preferably from 1 to 500 μm, and if it is less than 1 μm, it is difficult to obtain moisture-proof properties.
0 μm, more preferably 1 to 250 μm. The present invention will be described below in detail with reference to examples. <Examples 1 to 4> Vinyl chloride resin 1 having an average degree of polymerization of 700
The additives shown in Table 1 were blended in 00 parts by weight, kneaded between two rolls at 155 ° C. for 3 minutes, and hot-pressed at 140 ° C. for 2 minutes to obtain a sheet-like vinyl chloride resin layer (A). Was. The obtained vinyl chloride resin layer (A) was evaluated for blackening time, initial coloring, softening temperature and calenderability.
Next, after one or both surfaces of the obtained vinyl chloride resin layer (A) are anchor-coated and dried, a vinylidene chloride resin emulsion (L-530, manufactured by Asahi Chemical Industry Co., Ltd.)
And dried to obtain a vinylidene chloride resin layer (B).
Secondary workability and moisture resistance were evaluated. In addition, the agent for the anchor coat between the layers (A) and (B) was prepared by blending the rack skin UB-520: U-4000 = 10: 1 manufactured by Seiko Chemical Co., Ltd. and then diluting 5-fold with ethyl acetate. Was used. Examples 5 to 7 100 parts by weight of a vinyl chloride resin having an average degree of polymerization of 700 were blended with the respective additives shown in Table 2 and kneaded between two rolls at 155 ° C. for 3 minutes. The plate was pressed on a hot plate for 1 minute to obtain a vinyl chloride resin layer (A).
The obtained vinyl chloride resin layer (A) was evaluated for blackening time, initial coloring, softening temperature and calenderability. Next, a vinylidene chloride resin layer (B) obtained by a hot-melt extrusion method was laminated on one side or both sides of the obtained vinyl chloride resin layer (A), and secondary workability and moisture resistance were evaluated. The same anchor coating agent as in Example 1 was used between the layers (A) and (B) during lamination. <Comparative Examples 1 to 12> Each of the additives shown in Tables 3, 4 and 5 was blended with 100 parts by weight of a vinyl chloride resin having an average degree of polymerization of 700, and kneaded between two rolls at 155 ° C. for 3 minutes.
Hot plate pressing was performed at 140 ° C. for 2 minutes to obtain a vinyl chloride resin layer (A). The obtained vinyl chloride resin layer (A) was evaluated for blackening time, initial coloring, softening temperature and calenderability. Next, the obtained vinyl chloride resin layer (A)
After anchor coating on one side or both sides of the above and drying, a vinylidene chloride resin emulsion (L-530, manufactured by Asahi Kasei Corporation) is applied and dried to obtain a vinylidene chloride resin layer (B). Workability and moisture resistance were evaluated.
The same anchor coating agent as in Example 1 was used between the layers (A) and (B). Comparative Example 9 is an example not including the vinylidene chloride resin layer (B). <Comparative Example 13> Vinyl chloride resin 10 having an average degree of polymerization of 300
0 parts by weight of each additive shown in Table 5 was added at 155 ° C.
After kneading between the rolls for 3 minutes, hot plate pressing was attempted at 140 ° C. for 2 minutes, but no good vinyl chloride resin layer (A) was obtained. <Comparative Example 14> Vinyl chloride resin 1 having an average degree of polymerization of 1300
After mixing each additive shown in Table 5 with 00 parts by weight and kneading the mixture between two rolls at 155 ° C. for 3 minutes, hot plate pressing was attempted at 140 ° C. for 2 minutes, but a good vinyl chloride resin layer (A) was obtained. Could not be obtained. Each evaluation method is as follows. (1) Blackening time (heat resistance stability) The obtained vinyl chloride resin layer (A) was put into a gear type aging tester set at 180 ° C, and a sample was taken out every 10 minutes until browning or blackening. (Min) was measured. (2) Initially coloring The obtained vinyl chloride resin layer (A) is overlaid with a thickness of 1 mm.
Preheat at 80 ° C. for 3 minutes, pressurize 100 kg / cm ² × 2 minutes to make a board, and measure the yellowness (b value) of the board using a colorimeter.
Was measured. (3) Flexible temperature Measured according to JIS K6734. (4) Calendering properties During the preparation and kneading of the vinyl chloride resin layer (A), the releasability of the sheet from the calender roll, and stains on the roll such as bleed and bloom were visually observed. ○… No problem, ×… There is a problem. <5> Forming with hot platen pressure forming machine with secondary workability plug. The shape of the molding and the feeding of the sheet after the molding were visually observed. ○… No problem, ×… There is a problem. <6> Moistureproofness Tables 1 to 5 show the evaluation results of Examples and Comparative Examples measured according to JIS Z0208. [Table 1] [Table 2] [Table 3] [Table 4] As described above, according to the present invention, a vinyl chloride resin sheet having excellent heat resistance during sheet processing, no deterioration in initial coloring, and moisture resistance can be obtained. .

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-7-48492 (JP, A) JP-A-1-113242 (JP, A) JP-A-57-199656 (JP, A) JP-A-2- 263853 (JP, A) JP-A-63-110241 (JP, A) JP-A-9-118767 (JP, A) JP-A-3-1557437 (JP, A) JP-A 8-252890 (JP, A) JP-A-9-52995 (JP, A) JP-A-9-31280 (JP, A) JP-A-57-164141 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 27/06 B32B 27/30

Claims (1)

(57) [Claims] [Claim 1] The thickness is 0.02 to 1 mm and JIS
Flexible temperature of 50-80 by flexible temperature test of K6734
The average degree of polymerization of the vinyl chloride resin layer (A)
A higher fatty acid salt of calcium is added to 100 parts by weight of the vinyl chloride resin, which is 0 to 1,000 . 0.1 to 2 parts by weight, higher fatty acid salt of zinc 01 to 2 parts by weight , 0.01 to 5 parts by weight of a hydrotalcite compound represented by the general formula (I), 0.1 to 5 parts by weight of an epoxidized vegetable oil,
Ester-based lubricants composed of compounds of lyserin and higher fatty acids
Agent 0.01 to 2 parts by weight, β-diketone compound 0.01 to
The resin layer (A) is composed of a composition to which 1 part by weight is added.
A vinylidene chloride resin layer (B) having a thickness of 1 to 500 μm on at least one surface of the vinyl chloride sheet having moisture resistance. _{[Mg W · Al X · (OH} ) Y · (CO 3) Z ] mH ₂ O ...... (I) where, W, X, Y, Z is the number of positive satisfying 2W + 3X = Y + 2Z, W is 2 ≦ W is in the range of 6 and m is a positive number and is in the range of 2 ≦ m ≦ 4.