CN1263798C - Vinyl chloride series resin paste for hollow forming and formed article therefrom - Google Patents

Abstract

The present invention provides a vinyl chloride resin paste for hollow molding that does not impair the sol viscosity of the vinyl chloride resin paste for hollow molding even if the remaining portion of the vinyl chloride resin paste heated in the hollow molding process is repeatedly used characteristics and the characteristics of the resulting molded products, etc. In addition, the present invention also provides a molded article formed using the above-mentioned vinyl chloride-based resin paste. The vinyl chloride-based resin paste for hollow molding contains a vinyl chloride-based resin for paste and cyclohexene carboxylate as a plasticizer. The above-mentioned vinyl chloride-based resin paste was molded by a hollow molding method to obtain a molded article.

Description

Vinyl chloride-based resin paste for hollow molding, molded articles formed therefrom

technical field

The present invention relates to a vinyl chloride resin paste for hollow molding and a molded product formed therefrom.

More specifically, the present invention relates to an acrylonitrile-butadiene- A vinyl chloride-based resin paste having excellent non-migration properties such as styrene resin (ABS resin) and polystyrene resin and excellent bleeding resistance, and a molded article formed therefrom.

The vinyl chloride-based resin paste for hollow molding mentioned in the present invention is generally called paste glue among those in the industry.

Background technique

Conventionally, vinyl chloride-based resin pastes have been manufactured and used by blending aromatic carboxylic acid esters as plasticizers with vinyl chloride-based resins for pastes. Among the aromatic carboxylic acid esters used, phthalate plasticizers, especially bis(2-ethylhexyl) phthalate (hereinafter referred to as DOP), have a relatively balanced variety of physical properties. , suitable for dip molding, coating molding, rotational molding, hollow molding, injection molding and other molding methods, and is widely used in residential interior decoration fields such as toys, gloves, wallpapers, and bed materials, as well as automotive fields such as linings and sealants. Various applications such as steel plate coating and canvas coating.

However, among the above-mentioned phthalate plasticizers, there are substances (so-called environmental hormones) that are suspected of disrupting endocrine action and affecting the reproduction and development of wild organisms and humans. As a development trend in the industry, it has been It is desired to develop plasticizers with excellent properties that can replace phthalate plasticizers such as DOP.

For this reason, for example, as an alternative plasticizer, acetyl tributyl citrate (ATBC) as a citrate plasticizer has been applied in some fields, but since the plasticizer itself has poor thermal decomposition resistance, There is a problem that the acid value of the plasticizer increases under high temperature conditions.

In particular, as a molding method widely used in toys and the like, the hollow molding method is to inject a vinyl chloride resin paste for hollow molding into a mold, and then heat it to remove the remaining ungelled vinyl chloride resin paste for hollow molding. It is discharged for reuse. At this time, since the temperature of the discharged vinyl chloride resin paste for hollow molding usually rises to 40 to 100° C., it is required to have thermal stability that can withstand repeated use.

However, none of the conventional plasticizers is satisfactory in terms of thermal stability capable of withstanding such repeated use. It is generally believed that one of the reasons is that heating oxidatively decomposes the alkyl group in the plasticizer molecule, so the acid value of the plasticizer increases.

The acid value of the plasticizer greatly affects the viscosity characteristics of the vinyl chloride resin paste for hollow molding, so it is required to have good stability in terms of processability (sagging during melting, uneven thickness, etc.) .

Therefore, a technique of using diisononyl adipate (DINA) as an adipate plasticizer has been proposed. According to this technique, although the initial viscosity can be reduced, there are thermal decomposition resistance, non-migration (for Polystyrene resin, etc.), bleeding resistance and other unsatisfactory problems.

In order to solve the above problems, various solutions have been proposed.

For example, a technique of using cyclohexane carboxylate as a plasticizer has been proposed (for example, refer to Patent Document 1). However, although this technology is good in bleeding resistance and non-migration (to ABS resin, to polystyrene resin, etc.), it is poor in thermal decomposition resistance, so the acid value of the plasticizer during heating There are problems with thermal stability (sol viscosity, thixotropy, etc.) of vinyl chloride resin paste for hollow molding during molding.

[Patent Document 1] JP-A-2001-207002 (page 2, paragraph "0005" to page 3, paragraph "0011")

Contents of the invention

An object of the present invention is to provide a vinyl chloride resin paste for hollow molding and a molded article formed therefrom, which is characterized in that even if the remaining components heated in the hollow molding process are repeatedly used, The vinyl chloride-based resin paste for hollow molding does not impair the sol viscosity characteristics of the vinyl chloride-based resin paste for hollow molding, the characteristics of the molded article to be obtained, and the like.

The inventors of the present invention conducted intensive studies to solve the above-mentioned problems. As a result, they found that by using cyclohexene carboxylate as a plasticizer in the vinyl chloride resin for paste (as an essential component), even if the hollow spacer is used repeatedly, The vinyl chloride-based resin paste for hollow molding that has not been gelled in the remaining part of the molding process does not suffer from the deterioration of the viscosity characteristics of the sol due to the increase in the acid value of the plasticizer during the heating process, and can improve the thermal decomposition resistance. Improve, thereby completed the present invention.

That is, the present invention provides a vinyl chloride-based resin paste for hollow molding, characterized by containing a vinyl chloride-based resin for paste and cyclohexene carboxylate as a plasticizer.

Furthermore, the present invention provides a molded article characterized in that it is obtained by molding a vinyl chloride resin paste by a hollow molding method, wherein the vinyl chloride resin paste contains a vinyl chloride resin for the paste and a plasticizer of cyclohexene carboxylate.

The present invention will be further described in detail below.

The vinyl chloride-based resin paste for hollow molding according to the present invention contains a vinyl chloride-based resin for paste and cyclohexene carboxylate as a plasticizer in a state where the vinyl chloride-based resin for paste is dispersed in the plasticizer. in the dose.

The vinyl chloride-based resin for paste used in the present invention is a vinyl chloride-based resin that can be used in a resin paste that can be used in a hollow molding method. Examples of the vinyl chloride-based resin for the paste include polyvinyl chloride-based resins, vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinyl stearate copolymer resins, vinyl chloride-ethylene copolymer resins, vinyl chloride-propylene copolymer resins, Resins, vinyl chloride-isobutylene copolymer resins, vinyl chloride-methacrylate copolymer resins, vinyl chloride-isobutyl vinyl ether copolymer resins, polyvinyl chloride copolymer resins of known monomers and vinyl chloride, and polyvinyl chloride Vinyl resins or chlorinated polyvinyl chloride resins in which hydrogen atoms are replaced by chlorine atoms in polyvinyl chloride copolymer resins have a spherical shape, for example. These polymers can be used singly or as a mixture of two or more.

The hollow molding referred to here refers to a processing method of forming a hollow molded product with a resin paste, which will be described in detail later.

The average particle size of the vinyl chloride-based resin for paste used in the present invention is preferably several μm or less, more preferably within a range of 0.02 to 2 μm.

The vinyl chloride resin for paste can be prepared by drying an emulsion obtained by emulsion polymerization of a monomer mixture such as vinyl chloride or a suspension obtained by microsuspension polymerization.

The above-mentioned emulsion polymerization generally uses a monomer mixture such as a chlorine-containing vinyl monomer such as vinyl chloride, an emulsifier such as sodium lauryl sulfate and dioctyl sodium sulfosuccinate as an anionic surfactant, and ammonium persulfate. , Potassium persulfate and other water-soluble catalysts are carried out in aqueous medium. In addition, it is also possible to introduce a hydrophilic group into a monomer and perform emulsifier-free (soap-free) emulsion polymerization without using an emulsifier.

In addition, microsuspension polymerization usually uses monomer mixtures such as vinyl chloride-containing vinyl monomers such as vinyl chloride, emulsifiers such as sodium lauryl sulfate and dioctyl sodium sulfosuccinate as anionic surfactants, and dispersion aids. agent, and oil-soluble catalysts such as lauryl peroxide and di-2-ethylhexyl peroxide, are dispersed into oil droplets by mechanical shearing with a homogenizer or the like in an aqueous medium and reacted.

As a drying method of the above-mentioned emulsion, suspension, etc., it includes, for example, spray drying and the like.

In the vinyl chloride-based resin paste for hollow molding according to the present invention, cyclohexene carboxylate is used as a plasticizer, and plasticizers other than cyclohexene carboxylate may be used in combination.

In this case, the content of cyclohexene carboxylate in the total plasticizer used is preferably in the range of 50 to 100% by weight, particularly preferably in the range of 70 to 100% by weight, most preferably, cyclohexene The content of carboxylate is 100% by weight. If the content of cyclohexene carboxylate is in the range of 50 to 100% by weight, the plasticizer has excellent thermal decomposition resistance, and has excellent sol viscosity, sol viscosity stability, bleeding resistance, non-migration The balance of sex and non-volatility.

As the cyclohexene carboxylate used in the present invention, it includes, for example, cyclohexene monocarboxylic acid ester, cyclohexene dicarboxylic acid diester, cyclohexene tricarboxylic acid triester, cyclohexene tetracarboxylic acid tetraester wait.

Among these cyclohexene carboxylic acid esters, cyclohexene dicarboxylic acid diester and cyclohexene tricarboxylic acid triester are preferable from the viewpoint of compatibility with the vinyl chloride resin for paste and non-volatility.

As the cyclohexene dicarboxylic acid diester, it includes, for example, 4-cyclohexene-1,2-dicarboxylic acid di(2-ethylhexyl) ester, 4-cyclohexene-1,2-dicarboxylic acid di Isononyl ester, diisodecyl 4-cyclohexene-1,2-dicarboxylate, diisononyl 2-cyclohexene-1,4-dicarboxylate, and the like.

In addition, as cyclohexenetricarboxylic acid triester, it includes, for example, 4-cyclohexene-1,2,3-tricarboxylic acid tris(2-ethylhexyl)ester, 5-cyclohexene-1,2, 4-triisononyl tricarboxylate, etc.

In addition, the acid value of the cyclohexene carboxylate used in the present invention is preferably 0.2 or less from the viewpoint of bleeding resistance.

The acid value here means the number of milligrams of potassium hydroxide necessary to neutralize the acid contained in 1 g of the sample.

The cyclohexene carboxylic acid ester used in the present invention can be produced, for example, by subjecting cyclohexene carboxylic acid and a monohydric alcohol to a condensation reaction by a known and commonly used method. For example, in a nitrogen stream, while stirring the specified raw materials, a reflux condenser can be added to reflux the excess monohydric alcohol until the acid value reaches 0.5 or less, preferably at a temperature of 130 to 250°C. The generated water is continuously removed under continuous heating, and then, preferably, at a temperature of 230 to 180° C., under 10 hPa, more preferably, under reduced pressure below 4 hPa, the unreacted alcohol is removed. Afterwards, neutralize if necessary, and then filter to obtain a plasticizer with specified properties.

Examples of the cyclohexene carboxylic acid that can be used here include cyclohexene monocarboxylic acid, cyclohexene dicarboxylic acid, cyclohexene tricarboxylic acid, cyclohexene tetracarboxylic acid, and the like. Among these cyclohexene carboxylic acids, cyclohexene dicarboxylic acid and cyclohexene tricarboxylic acid are preferable from the viewpoint of the compatibility and non-volatility of esterified products thereof with the vinyl chloride resin for paste.

As the aforementioned cyclohexene dicarboxylic acid, it includes, for example, 1-cyclohexene-1,2-dicarboxylic acid, 2-cyclohexene-1,2-dicarboxylic acid, 3-cyclohexene-1,2- Dicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, 4-methyl-4-cyclohexene-1,2-dicarboxylic acid, 1-cyclohexene-1,3-dicarboxylic acid , 3-cyclohexene-1,3-dicarboxylic acid, 4-cyclohexene-1,3-dicarboxylic acid, 1-cyclohexene-1,4-dicarboxylic acid, 2-cyclohexene-1 , 4-dicarboxylic acid, etc.

As the aforementioned cyclohexenetricarboxylic acid, it includes, for example, 1-cyclohexene-1,2,3-tricarboxylic acid, 3-cyclohexene-1,2,3-tricarboxylic acid, 4-cyclohexene- 1,2,3-tricarboxylic acid, 1-cyclohexene-1,2,4-tricarboxylic acid, 2-cyclohexene-1,2,4-tricarboxylic acid, 3-cyclohexene-1, 2,4-tricarboxylic acid, 4-cyclohexene-1,2,4-tricarboxylic acid, 5-cyclohexene-1,2,4-tricarboxylic acid, 6-cyclohexene-1,2, 4-tricarboxylic acid, 1-cyclohexene-1,3,5-tricarboxylic acid, etc.

In addition to the above cyclohexene carboxylic acids, ester-forming derivatives such as their anhydrides or their acid chlorides can be used instead of the cyclohexene carboxylic acids. In addition, alkyl ester compounds of these cyclohexenecarboxylic acids can also be used. Among the alkyl ester compounds to be used, lower alkyl ester compounds are preferable because the dealcoholization reaction step can be carried out under mild conditions, and among them, methyl ester compounds are particularly preferable.

These substances may be used alone or in combination of two or more.

As the monohydric alcohol usable in the production of the cyclohexene carboxylate used in the present invention, it includes, for example, butanol, isobutanol, hexanol, isohexanol, heptanol, isoheptanol, octanol, isooctyl alcohol, 2-Ethylhexanol, Nonanol, Isononanol, 2-Methyloctanol, Decyl Alcohol, Isodecanol, Undecyl Alcohol, Dodecyl Alcohol, Tridecyl Alcohol, etc.

These monohydric alcohols may be used alone or in combination of two or more.

These alcohols constitute alcohol units in the cyclohexene carboxylate obtained by the condensation reaction with the above-mentioned cyclohexene carboxylic acid.

As the aforementioned alcohol, a monohydric alcohol having an alkyl group having a carbon number in the range of 6 to 11 is preferable. If the carbon number of the monoalcohol alkyl group is in the range of 6 to 11, the obtained cyclohexene carboxylate has excellent non-volatility and excellent compatibility with vinyl chloride resin for paste.

As the monohydric alcohol having an alkyl group having a carbon number ranging from 6 to 11 to be used, it includes, for example, hexanol, isohexanol, heptanol, isoheptanol, octanol, isooctyl alcohol, 2-ethylhexanol, Nonanol, isononanol, 2-methyloctanol, decyl alcohol, isodecyl alcohol, undecyl alcohol, etc.

In addition, among the above-mentioned monohydric alcohols having an alkyl group having a carbon number ranging from 6 to 11, monohydric alcohols having a hydroxyl value ranging from 370 to 420 are particularly preferable. Examples of monohydric alcohols having an alkyl group having a carbon number in the range of 6 to 11 and a hydroxyl value in the range of 370 to 420 include nonanol, isononanol, 2-methyloctanol, and the like. The cyclohexene carboxylate obtained by using a monohydric alcohol satisfying both the carbon number of the alkyl group and the range of the hydroxyl value has excellent non-volatility and compatibility with the vinyl chloride resin for paste.

The hydroxyl value mentioned here refers to the number of milligrams of potassium hydroxide required to neutralize acetic acid produced when 1 g of a sample is reacted with an acetylating agent at a predetermined temperature and time according to a predetermined method.

When carrying out the condensation reaction for synthesizing the cyclohexene carboxylate used in the present invention, it is preferable to use a catalyst in order to promote the progress of the condensation reaction. The catalyst used includes, for example, acid catalysts such as p-toluenesulfonic acid and phosphoric acid, metal catalysts such as tetraisopropyl titanate, tetrabutyl titanate, dibutyltin oxide, dioctyltin oxide, and zinc chloride.

Moreover, the temperature at the time of this condensation reaction becomes like this. Preferably it is 100-250 degreeC, More preferably, it is 130-250 degreeC.

In the vinyl chloride-based resin paste for hollow molding according to the present invention, known plasticizers may be used in addition to cyclohexene carboxylate. It includes, for example, phthalates, adipates, sebacates, trimellitates, pyromellitates, epoxy esters such as epoxidized soybean oil, chlorinated paraffins , phosphate esters, polyesters, cyclohexane carboxylate, etc.

The amount of the plasticizer used in the vinyl chloride resin paste for hollow molding according to the present invention is preferably 10 to 300 parts by weight, particularly preferably 20 to 200 parts by weight, based on 100 parts by weight of the vinyl chloride resin for paste. When the usage-amount of the said plasticizer in the vinyl chloride-type resin paste for hollow molding is in the said range, processing viscosity is easy to adjust in a hollow molding process, and bleeding does not generate|occur|produce.

The vinyl chloride resin paste for hollow molding according to the present invention usually incorporates a heat stabilizer in order to suppress the dehydrochlorination reaction of the vinyl chloride resin for paste caused by heating when the vinyl chloride resin paste is hollow molded.

Examples of the heat stabilizers include various heat stabilizers such as lead-based, tin-based, Ba-Zn-based, Ca-Zn-based, Zn-K-based, Zn-Na-based, and the like. The amount of the heat stabilizer used is preferably within a range of 0.1 to 10 parts by weight relative to 100 parts by weight of the vinyl chloride resin for paste.

The vinyl chloride-based resin paste for hollow molding according to the present invention may further contain various additives within a range that does not impair the object of the present invention. As the additive used, it includes, for example, an antioxidant, an ultraviolet absorber, a filler, a diluent, a foaming agent, a stabilizing assistant, and the like.

As the antioxidant, it includes, for example, phenolic antioxidants such as 2,6-di-tert-butyl-p-cresol, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl ) hindered phenol-based antioxidants such as propionate, sulfide-based antioxidants such as dilauryl thiodipropionate, and phosphoric acid-based antioxidants such as trinonylphenol phosphate. The amount of the antioxidant to be used is preferably in the range of 0.1 to 10 parts by weight relative to 100 parts by weight of the vinyl chloride resin for paste.

As the above-mentioned ultraviolet absorber, it includes, for example, salicylate-based compounds such as phenyl salicylate, benzophenone-based compounds such as 2-hydroxy-4-methoxybenzophenone, 2-(2'-hydroxyl -Benzotriazole-based compounds such as 5'-tert-butylphenyl)benzotriazole, cyanoacrylate-based compounds such as 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate , hindered amine compounds such as bis(2,2,6,6-tetramethyl-4-nitrohexanyl) sebacate, and the like. It is preferable that the compounding quantity of the ultraviolet absorber used is the range of 0.1-10 weight part with respect to 100 weight part of vinyl chloride-type resins for pastes.

As the aforementioned filler, it includes, for example, calcium carbonate, clay, talc, silica, aluminum hydroxide, magnesium oxide, magnesium carbonate, magnesium silicate, calcium silicate and the like. It is preferable that the compounding quantity of the filler to be used exists in the range of 1-120 weight part with respect to 100 weight part of vinyl chloride-type resins for pastes.

As the aforementioned diluent, it includes, for example, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, n-alkane, and the like. It is preferable that the compounding quantity of the diluent to be used exists in the range of 1-50 weight part with respect to 100 weight part of vinyl chloride-type resins for pastes.

As the aforementioned foaming agent, it includes, for example, an organic foaming agent represented by azodicarbonamide and p,p'-oxybisbenzenesulfonyl hydrazide, an inorganic foaming agent represented by sodium bicarbonate, and the like. It is preferable that the compounding quantity of the foaming agent used exists in the range of 0.1-30 weight part with respect to 100 weight part of vinyl chloride-type resins for pastes.

In addition, as the aforementioned stabilizing aids, epoxy compounds such as epoxidized soybean oil, epoxidized linseed oil, epoxy butyl stearate, and the like are included, for example.

It is preferable that the compounding quantity of the said stabilization aid exists in the range of 0.5-50 weight part with respect to 100 weight part of vinyl chloride-type resins for pastes.

The thus obtained paste is mixed and stirred with a vinyl chloride resin, cyclohexene carboxylate as a plasticizer, various additives, etc., and the paste is dispersed with a vinyl chloride resin and various additives, etc., if necessary. In this plasticizer, the vinyl chloride-type resin paste for hollow molding which concerns on this invention which consists of this plasticizer and the vinyl chloride-type resin for pastes dispersed in this plasticizer can be prepared.

Examples of devices that can be used for mixing, stirring, and dispersing the components constituting the above-mentioned vinyl chloride resin paste for hollow molding include kneaders, butterfly mixers, planetary mixers, Henschel mixers, and pulverizers. wait.

The so-called hollow molding is a kind of vinyl chloride resin paste for hollow molding formed by uniformly dispersing the vinyl chloride resin for paste in the plasticizer to give a shape, and it is gelled and melted by heating. And make the forming method of molding.

Vinyl chloride resin for paste for hollow molding, for general-purpose vinyl chloride resin with a particle size of about 100 μm, since the vinyl chloride resin for paste is a fine spherical particle with a particle size of several μm or less, it is suitable for hollow molding. Vinyl chloride-based resin paste can maintain a stable solid-liquid dispersion state, and can produce a homogeneous molded product using only heat energy.

The molded article according to the present invention can be produced by blow molding the thus obtained vinyl chloride resin paste for blow molding.

The vinyl chloride-based resin paste for hollow molding according to the present invention contains cyclohexene carboxylate as a plasticizer, so the acid value generated by thermal decomposition of the plasticizer during the heating process is repeated. Since it has little rise and is excellent in thermal decomposition resistance, it can be used particularly effectively for blow molding.

"Blow molding" as used in the present invention generally refers to a molding method in which a molded article is obtained by sequentially passing through the following steps (1) to (4).

Step (1): The vinyl chloride resin paste for hollow molding is poured into the mold from the paste tank, and the mold is heated to gel the vinyl chloride resin paste for hollow molding in contact with the inner wall surface of the mold to form a gel. layers.

Step (2): Heating is stopped, and the remaining ungelled vinyl chloride resin paste for hollow molding other than the gelled layer is discharged and recovered into a paste tank.

Step (3): Heating the mold again to melt the gelled layer and complete the gelation.

Step (4): The mold is cooled, and the molded product is taken out.

The hollow molded article which is the object of the present invention can be obtained through the above-mentioned steps in sequence.

In addition, the mold used in the above-mentioned process is a shell-shaped object having a concavo-convex portion having a desired design pattern, etc. on the inner wall surface.

The method of heating the mold in the step (1) is not particularly limited as long as it can heat the mold. It includes, for example, a method using an oil bath, a method using an air heating furnace, and the like. In addition, the heating temperature is usually a temperature at which the vinyl chloride-based resin paste for hollow molding can be gelled, and is preferably in the range of 120 to 200°C.

In addition, since the gelled layer in step (1) becomes thicker with time, the layer thickness of the molded product can be adjusted by setting an appropriate heating stop time according to the type of molded product.

The ungelled vinyl chloride resin paste for hollow molding recovered in the paste tank in step (2) is reused in the hollow molding step (1). The vinyl resin paste is recovered into the paste tank, and this process is repeated many times thereafter so that it can be used repeatedly.

The cooling method of the mold in the step (4) is not particularly limited, and for example, cooling with water can be used.

The molded article according to the present invention uses a vinyl chloride-based resin paste for hollow molding, and the vinyl chloride-based resin paste for hollow molding uses a plasticizer containing the above-mentioned cyclohexene carboxylate according to the present invention as an essential component. Therefore, even if the vinyl chloride resin paste for hollow molding is repeatedly used, the acid value of the plasticizer due to thermal decomposition during the heating process is rarely increased, and non-bleeding (phase of the plasticizer) can often be obtained. Capacitance), non-migration, non-volatility and other characteristics of the excellent balance of molded products.

The molded article according to the present invention includes, for example, toys, gloves, automobile parts and the like.

As the molded article according to the present invention, toys are preferable among the above-mentioned molded articles from the viewpoint of requiring particularly high aesthetic appearance.

As the toy produced in the present invention, it includes, for example, dolls which are soft plastic toys, figure goods, children's play goods, mannequins and the like.

Since these toys are usually used in contact with or in combination with ABS resin or polystyrene resin in the composition of the product, it is required that the plasticizer in the vinyl chloride resin paste for hollow molding does not contribute to these resins in contact with or in combination with it. Migrating (that is, having non-migrating properties), the toy as the molded article of the present invention is excellent in this respect.

Detailed ways

The present invention will be described in more detail below in conjunction with the examples. The "powder" in the text is all based on weight.

"Examples 1-4" and "Comparative Examples 1-5"

According to the compounding composition shown in Table 1 and Table 2, a vinyl chloride resin paste for hollow molding containing a vinyl chloride resin for paste, a plasticizer and additives was prepared, and a sheet was made from it. The thermal decomposition resistance, sol viscosity, exudation resistance, non-migration and non-volatility of these vinyl chloride resin pastes for hollow molding, plasticizers, and molded products were evaluated, and the results are shown in Tables 1 and 2. .

The preparation and evaluation methods of this vinyl chloride-based resin paste for hollow molding are as follows.

[Preparation of vinyl chloride resin paste for hollow molding]

According to the compounding ratio shown in Table 1 and Table 2, use a mixing mixer [Tokyo Rikaki Co., Ltd., chemistara-B-100], mix and stir under the condition of 1100 rpm and 4 minutes at the stirring speed, and then Under reduced pressure, static defoaming was performed for 30 minutes to prepare a vinyl chloride resin paste for hollow molding in which a vinyl chloride resin for paste was dispersed.

[Flake Baking Conditions]

The vinyl chloride-based resin paste for hollow molding obtained in Examples and Comparative Examples was made into a test piece, and coated on a glass plate with a thickness of 1 mm After thickening, bake at 190°C for 10 minutes to make thin slices.

[Measuring method and evaluation criteria of thermal decomposition resistance of plasticizers]

100 g of the plasticizer used in Examples and Comparative Examples was put into a 250 cc sample bottle, and was heated in a drier at 100° C. for 14 days with the lid left open. After the test, the acid value of the plasticizer was measured, compared with the initial acid value, and evaluated according to the following criteria.

○: acid value is less than 2

×: The acid value is 2 or more

[Measurement method and evaluation criteria of sol viscosity stability]

<Measurement of initial sol viscosity>

Using a BM-type viscometer, according to Rota-No. 3, under the conditions of 6 rpm and a measurement temperature of 25° C., the vinyl chloride-based resin pastes for hollow molding obtained in Examples and Comparative Examples were measured.

<Measurement of Sol Viscosity Stability>

Under the condition of 25°C, the above-mentioned vinyl chloride resin paste for hollow molding was stored for 7 days, and under the same conditions as the initial sol viscosity, the sol viscosity was measured with a BM type viscometer.

The ratio of the sol viscosity after 7 days to the initial sol viscosity (sol viscosity after 7 days/initial sol viscosity) was calculated and evaluated according to the following evaluation criteria.

○: less than 1.5 times

×: 1.5 times or more

[Measuring method and evaluation criteria of bleeding resistance]

Cut the thin slice prepared above into a size of 5cm × 5cm, and use it as a test piece, and observe the appearance of the thin slice visually after 10 days, 20 days, 30 days and 40 days under the conditions of 70°C and 95% relative humidity. The state was evaluated according to the following evaluation criteria.

○: No bleeding.

Δ: No bleed-out, but stickiness on the surface increased.

×: seepage

Hardening: No bleeding, but the plasticizer volatilizes and the test piece hardens.

[Measurement method and evaluation criteria of non-migration]

The sheet obtained above was cut into a size of 2.5mm x 2.5mm, which was used as a test piece, and an ABS resin plate [manufactured by Asahi Kasei Industry Co., Ltd., STAILUCK 121] and a HIPS resin (high-impact polystyrene resin) plate were used. [Manufactured by A&M Styrene Co., Ltd., AGI02], each test piece is sandwiched between two resin plates to form a "sandwich" shape, and it is held at 40°C under a load of 10g/ ^cm2 for 24 hours. The erosion state due to migration of the plasticizer to the ABS resin plate and the HIPS resin plate was observed visually, and evaluated according to the following evaluation criteria.

◯: Erosion to the resin plate due to migration of the plasticizer was not observed.

Δ: No attack to the resin plate due to migration of the plasticizer occurred, but traces were slightly observed.

×: Erosion to the resin plate due to migration of the plasticizer was observed.

××: Erosion to the resin plate due to migration of the plasticizer was clearly observed.

[nonvolatile measurement method]

The sheet obtained above was cut into a size of 5 cm x 5 cm and used as a test piece. After the weight (a) was measured in advance, it was placed in a dryer and dried at 100° C. for 120 hours. Then, the sheet was taken out, and the weight (b) was measured again thereafter, and the weight loss rate (%) was obtained from the following calculation formula.

Weight reduction rate (%)=(a-b)/a×100

【Table 1】 Table 1 Example 1 Example 2 Example 3 Comparative example 1 Comparative example 2 Comparative example 3 Vinyl chloride resin ^*1) (parts) 100 100 100 100 100 100 Cyclohexene system A (part)Cyclohexene system B (part)Cyclohexene system C (part) 50 50 50 DOP (parts)DINA (parts)ATBC (parts) 50 50 50 Epoxidized soybean oil ^*2 (parts) Ca/Zn series stabilizer ^*3 (parts) 53 53 53 53 53 53 Evaluation of thermal decomposition resistance of plasticizers after the initial 14 days of acid value (mgKOH/g) 0.110.71○ 0.030.50○ 0.150.85○ 0.033.15× 0.0810.15× 0.103.75× Sol Viscosity Evaluation of Viscosity Stability After 7 Days Initially (25°C, mPa.s) 55405730○ 60206230○ 66606720○ 61509840× 24305120× 41507310× Exudation resistance After 10 days, after 20 days, after 30 days, after 40 days ○○○○ ○○○○ ○○○△ ○○○○ ○△×× hardened hardened hardened hardened Non-migrating ABS resin board HIPS resin board ○△ ○△ ○△ ○△ ○×× ×××× Non-volatile weight reduction rate (%) 7.9 4.7 3.1 7.2 8.8 19.3

【Table 2】

In Example 4 and Comparative Example 5, the evaluation items described in Table 2 were performed using the plasticizer 14 days after the start of the thermal decomposition resistance test.

[Description and notes of plasticizers listed in Table 1 and Table 2]

Cyclohexene system A: 4-cyclohexene-1,2-dicarboxylic acid bis(2) composed of 4-cyclohexene-1,2-dicarboxylic acid and 2-ethylhexanol (hydroxyl value 432) -ethylhexyl) ester. The viscosity is 37mPa.s (25°C).

Cyclohexene-based B: 4-cyclohexene composed of 4-cyclohexene-1,2-dicarboxylic acid and isononanol (manufactured by Kyowa Hakko Co., Ltd., trade name; Okisocol 900, hydroxyl value 390) Diisononyl ene-1,2-dicarboxylate. Viscosity 48mPa.s (25°C).

Cyclohexene-based C: Diisodecyl 4-cyclohexene-1,2-dicarboxylate composed of 4-cyclohexene-1,2-dicarboxylic acid and isodecyl alcohol (hydroxyl value: 355). Viscosity 67mPa.s (25°C).

DOP: Di(2-ethylhexyl) phthalate.

DINA: Diisononyl adipate.

ATBC: Acetyl tributyl citrate.

Cyclohexane series: Cyclohexane-1,2-dicarboxylic acid and isononanol (manufactured by Kyowa Hakko Co., Ltd., trade name; Okisocol 900) subjected to condensation reaction - diisononyl dicarboxylate. Viscosity 42mPa.s (25°C).

^* 1) Polyvinyl chloride resin for paste (polymerization degree 1650)

^* 2) Stabilizing agent, manufactured by Dainippon Ink & Chemicals Co., Ltd., W-100-EL

^* 3) Heat stabilizer, manufactured by Dainippon Ink & Chemicals Co., Ltd., ゲレツクML-610A

According to the results of Table 1 and Table 2, it can be seen that the vinyl chloride resin paste for hollow molding used in the present invention is equivalent to DOP in terms of sol viscosity, exudation resistance, non-migration, and non-volatility. Vinyl chloride resin paste for hollow molding contains cyclohexene carboxylate as a plasticizer, so it has excellent heat resistance stability and sol viscosity stability.

Among them, Example 2 in which the hydroxyl value of the alcohol unit constituting the cyclohexene carboxylate is 390 has a very good balance of sol viscosity, bleeding resistance, non-migration, and non-volatility.

The vinyl chloride-based resin paste for hollow molding according to the present invention contains cyclohexene carboxylate as a plasticizer as an essential component, so it is more effective than the conventionally known vinyl chloride-based resin paste for hollow molding. Even if it is repeatedly heated and used in the hollow molding process, the alkyl portion of the plasticizer is not easily thermally decomposed during the heating process, and has excellent thermal decomposition resistance, and excellent viscosity stability, non-migration, bleeding resistance, and non-volatility. Therefore it is extremely suitable for blow molding. It can be widely used in hollow molded articles such as toys mainly molded by a hollow molding method.

Claims (5)

1. A vinyl chloride resin paste for hollow molding, characterized in that it contains a vinyl chloride resin for the paste and a cyclohexene carboxylate as a plasticizer, with respect to 100 parts by weight of the vinyl chloride resin for the paste, The content of the plasticizer is 10 parts by weight to 300 parts by weight, and the content of the cyclohexene carboxylate is 50 to 100 parts by weight relative to the total amount of the plasticizer. 2. The vinyl chloride resin paste for hollow molding according to claim 1, wherein the alcohol unit constituting the cyclohexene carboxylate is derived from a monohydric alcohol having an alkyl group having 6 to 11 carbon atoms. 3. The vinyl chloride resin paste for hollow molding according to claim 1 or 2, wherein the alcohol unit constituting the cyclohexene carboxylate is derived from a monohydric alcohol having a hydroxyl value in the range of 370 to 420. 4. A molded product characterized in that it is obtained by molding a vinyl chloride-based resin paste by a hollow molding method, and the vinyl chloride-based resin paste contains a vinyl chloride-based resin for paste and cyclohexene carboxylic acid as a plasticizer ester, with respect to 100 parts by weight of the above-mentioned vinyl chloride resin for paste, the content of the plasticizer is 10 parts by weight to 300 parts by weight, and relative to the total amount of the plasticizer, the cyclohexene carboxylic acid The ester content is 50 to 100% by weight. 5. The molded article according to claim 4, wherein the molded article is a toy.