JP5628539B2 - Clarifying agent composition with improved effect of dibenzylidene sorbitol-based clarifying agent - Google Patents

Description

  In the present invention, a diphenylidene sorbitol-based clarifying agent having a large particle size, which has been conventionally regarded as unsuitable for addition during processing of a polypropylene-based resin, is preliminarily mixed with a specific phenol-based antioxidant before mixing with the resin. It is related with the clearing agent composition which can shape | mold the polypropylene-type resin composition excellent in transparency by adding this mixture to resin after mixing.

  Polypropylene resins such as propylene homopolymers and ethylene-propylene copolymers are widely used in automobiles, home appliances, building materials, furniture, packaging containers, toys, daily miscellaneous goods, and the like. However, since polypropylene resins are inferior to polyethylene, polyethylene terephthalate, polycarbonate, polystyrene, etc. in transparency, benzoic acid metal salts, aromatic phosphate metal salts, metal salts of aliphatic cyclic compounds, dibenzylidene sorbitols, amides Incorporating various nucleating agents such as compounds and clearing agents has been proposed and put into practical use.

  Among them, although dibenzylidene sorbitols are excellent in the effect of improving transparency, they have disadvantages such as strong odor, high melting point, and difficulty in uniform dispersion in the resin at the processing temperature. Although uniform dispersion is possible by setting the processing temperature to the melting point or higher, the compound represented by the general formula (I) used in the present invention has a high melting point of 260 ° C. or higher, and processing at the melting point or higher is remarkable for polypropylene. This is not preferable because it causes excessive deterioration. In order to improve the dispersibility in the resin below the melting point, various treatments such as reducing the particle size by pulverization or lowering the melting point by melting and mixing with other components in advance have been proposed.

For example, Patent Document 1, dibenzylidene sorbitols, d ₉₇ has been proposed to express the performance by the following powder 30 [mu] m. Although this dibenzylidene sorbitol is excellent in the effect of improving the transparency, the fluidity is reduced by making it a fine powder, so that the handling properties such as weighing and preparation are lowered, and the dispersibility expected by blocking is also achieved. There are problems such as inability to obtain. In addition, the finely pulverized product actually needs to prevent secondary agglomeration with an inorganic material or a surface treatment agent, which increases the manufacturing cost and adds unnecessary components to the resin. Differentiating is not always a satisfactory solution because the mixing of unnecessary components is accompanied by unintended changes in resin physical properties and causes quality degradation during recycling and limited use.

  Patent Document 2 proposes improving the performance by using a mixture of dibenzylidene sorbitol compounds having different structures. Since a melting point drop occurs by using a mixture of similar structures, the dispersibility in the resin is improved. However, among the dibenzylidene sorbitols, a clearing agent having another structure is added to a compound that is particularly effective, and this is not a sufficient solution because the clearing effect is reduced.

  In addition, polypropylene alone degrades at the processing temperature, so it is indispensable to add additive components such as phenolic antioxidants and phosphorous antioxidants. These additive components are composed of polypropylene powder and pellets. It is conventionally performed to be blended with a nucleating agent and a clarifying agent. As described in Patent Document 1 as a comparative example, even if these other additive components are blended with a resin together with dibenzylidene sorbitols and mixed with a Henschel mixer or the like, the dispersibility of the dibenzylidene sorbitols is improved. It could not be improved.

Japanese Patent Laid-Open No. 06-145431 JP 02-206627 A

  An object of the present invention is to provide a dibenzylidene sorbitol-based clarifying agent capable of forming a polypropylene resin composition having excellent transparency by blending a dibenzylidene sorbitol compound into a polypropylene-based resin without pulverizing. is there.

The present invention relates to 100 parts by mass of a dibenzylidene sorbitol compound represented by the following general formula (I) in which d ₉₇ is 31 μm or more and 200 μm or less in particle size, and tetrakis [3 (3,5-di- a mixture of tert-butyl-4-hydroxyphenyl) propionyloxy methyl] methane 10-200 parts by state, and are more than 50% by weight of the total mixture of both components, the mixture, the components, the mixing apparatus The object is achieved by providing a clarifying agent composition that is used and mixed .
In addition, the present invention relates to 100 parts by mass of a dibenzylidene sorbitol compound represented by the following general formula (I) having a particle size of d ₉₇ of 31 μm or more and 200 μm or less, tetrakis [3 (3,5-di- Tert-butyl-4-hydroxyphenyl) propionyloxymethyl] is a mixture with 10 to 200 parts by mass of methane, the total of both components being 50% by mass or more of the mixture. The object is achieved by providing a method for producing a clarifying agent composition, wherein the components are mixed using a mixing device.

  According to the present invention, a dibenzylidene sorbitol compound having a large particle diameter, which has not been sufficiently transparent in the prior art, is mixed with a specific phenol-based antioxidant and then added to a polypropylene-based resin. A clarifying agent composition capable of forming a polypropylene resin composition having excellent transparency without finely pulverizing a benzylidene sorbitol compound can be provided.

  The dibenzylidene sorbitol compound represented by the general formula (I) used in the present invention is not particularly limited to its production method, and may be any known method.

The particle size of the dibenzylidene sorbitol compound represented by the general formula (I) used in the present invention is such that d ₉₇ is 30 μm or more and 200 μm or less, d ₉₇ is preferably 40 μm or more and 150 μm or less, and d ₉₇ is 40 μm or more. 100 μm or less is particularly preferable. When d ₉₇ is pulverized to less than 30 μm, the pulverization cost becomes high, and further, blocking occurs, handling property is lowered, and dispersibility in the resin is also lowered. When d ₉₇ is larger than 200 μm, there are problems such as insufficient transparency and an increase in fish eyes when formed into a film or the like. In the present invention, d ₉₇ is a particle size in which the percentage of the particle amount smaller than a certain particle size is 97 with respect to the total particle amount.

  Tetrakis [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] methane used in the present invention includes its intermediates, production method, crystal form, melting point, infrared absorption spectrum, X-ray A diffraction peak etc. can be used without limitation.

  The clarifying agent composition of the present invention comprises tetrakis [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl added to 100 parts by mass of the dibenzylidene sorbitol compound represented by the general formula (I). ] 5 to 200 parts by mass of methane, preferably 10 to 150 parts by mass. Mixing conditions such as mixing apparatus and temperature are not particularly limited, and various mixing apparatuses such as a Henschel mixer can be used. . Since it is not particularly necessary to melt, it is preferable to perform mixing at room temperature without performing treatment that leads to cost increase such as heating and cooling. In addition, mixing at room temperature is preferable because there is no concern of coloring during mixing. Moreover, in order to suppress the coloring by the oxidation at the time of heat-kneading with resin, you may perform a mixing process in nitrogen atmosphere.

The clarifying agent composition of the present invention comprises both a dibenzylidene sorbitol compound represented by the general formula (I) and tetrakis [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] methane. The total of the components is 50% by mass or more of the mixture, preferably 80% by mass or more, particularly preferably 100% by mass.
Examples of components other than the two components that can be blended in the clarifying agent composition of the present invention include antioxidants, hindered amine compounds, and other nucleating agents.

  The clarifying agent composition of the present invention is particularly effective for improving the transparency of polypropylene resins. Examples of polypropylene resins include propylene homopolymers, ethylene-propylene random copolymers, ethylene-propylene block copolymers, and propylene. And other α-olefins (for example, 1-butene, 1-hexene, 4-methyl-1-pentene, etc.), a copolymer of a small amount (1 to 10% by mass), a copolymer of propylene and ethylenepropylene ( TPO).

  The above-mentioned polypropylene resins are the types and presence / absence of polymerization catalyst / co-catalyst, stereoregularity, average molecular weight, molecular weight distribution, presence / absence and ratio of specific molecular weight components, specific gravity, viscosity, solubility in various solvents, elongation rate, impact Strength, crystallinity, X-ray diffraction, unsaturated carboxylic acids (maleic acid, itaconic acid, fumaric acid, etc.) and their derivatives (maleic anhydride, maleic acid monoester, maleic diester, etc.), organic peroxides or energy It can be used regardless of the presence or absence of modification / crosslinking treatment by irradiation of rays and a combination of these treatments.

  The clearing agent composition of the present invention is preferably blended in an amount of 0.01 to 10 parts by weight, and more preferably 0.05 to 5 parts by weight with respect to 100 parts by weight of the polypropylene resin.

  The polypropylene resin composition containing the clearing agent composition of the present invention includes phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, ultraviolet absorbers, hindered amines depending on the use conditions and required characteristics. Compound, Flame retardant, Flame retardant aid, Other nucleating agent, Antistatic agent, Heavy metal deactivator, Plasticizer, Softener, Lubricant, Hydrotalcite, Fatty acid metal salt, Pigment, Infrared absorber, Anti-fog It is preferable to add general-purpose resin additives such as agents, anti-fogging agents, fillers, antibacterial and antifungal agents.

  Examples of phenolic antioxidants include 2,6-ditert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, 2-methyl-4,6-bis (octylthiomethyl) phenol, Distearyl (3,5-ditert-butyl-4-hydroxybenzyl) phosphonate, 1,6-hexamethylenebis [(3,5-ditert-butyl-4-hydroxyphenyl) propionic acid amide], 4,4 '-Thiobis (6-tert-butyl-m-cresol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol) 4,4′-butylidenebis (6-tert-butyl-m-cresol), 2,2′-ethylidenebis (4,6-ditert-butylphenol), 2,2′-ethylide Bis (4-secondarybutyl-6-tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-tris (2, 6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate, 1,3,5-tris (3,5-ditert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (3,5-ditert-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 2-tert-butyl-4-methyl-6- (2-acryloyloxy-3-tert-butyl-5 -Methylbenzyl) phenol, stearyl (3,5-ditert-butyl-4-hydroxyphenyl) propionate, thiodiethylene glycol bis [(3,5-ditert-butyl-4-hydroxyphenyl) ) Propionate], 1,6-hexamethylene bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate], bis [3,3-bis (4-hydroxy-3-tert-butylphenyl) buty Rick acid] glycol ester, bis [2-tert-butyl-4-methyl-6- (2-hydroxy-3-tert-butyl-5-methylbenzyl) phenyl] terephthalate, 1,3,5-tris [(3 , 5-Ditert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tetrakis [methyl 3- (3,5-ditert-butyl-4-hydroxyphenyl) propionate] methane, 3,9-bis [1,1-dimethyl-2-{(3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4, , 10-tetraoxaspiro [5.5] undecane, triethylene glycol bis [(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate] and the like, preferably with respect to 100 parts by weight of the resin Is used in an amount of 0.001 to 10 parts by weight, more preferably 0.05 to 5 parts by weight.

  Examples of phosphorus antioxidants include trisnonylphenyl phosphite, tris (2,4-ditert-butylphenyl) phosphite, tris [2-tert-butyl-4- (3-tert-butyl-4- Hydroxy-5-methylphenylthio) -5-methylphenyl] phosphite, tridecyl phosphite, octyl diphenyl phosphite, di (decyl) monophenyl phosphite, di (tridecyl) pentaerythritol diphosphite, di (nonylphenyl) ) Pentaerythritol diphosphite, bis (2,4-ditert-butylphenyl) pentaerythritol diphosphite, bis (2,6-ditert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2 , 4,6-Tritert-butylphenyl) pentaerythritol diphos Bis (2,4-dicumylphenyl) pentaerythritol diphosphite, tetra (tridecyl) isopropylidenediphenol diphosphite, tetra (tridecyl) -4,4′-n-butylidenebis (2-tert-butyl- 5-methylphenol) diphosphite, hexa (tridecyl) -1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butanetriphosphite, tetrakis (2,4-ditert-butylphenyl) ) Biphenylene diphosphonite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 2,2′-methylenebis (4,6-tert-butylphenyl) -2-ethylhexyl phosphite 2,2'-methylenebis (4,6-tert-butylphenyl) -octadecyl Phosphite, 2,2′-ethylidenebis (4,6-ditert-butylphenyl) fluorophosphite, tris (2-[(2,4,8,10-tetrakis tert-butyldibenzo [d, f] [ 1,3,2] dioxaphosphin-6-yl) oxy] ethyl) amine, 2-ethyl-2-butylpropylene glycol and 2,4,6-tritert-butylphenol phosphite.

As the sulfur-based antioxidant, dilauryl thiodipropionate, dimyristyl thiodipropionate, dipalmityl thiodipropionate, distearyl thiodipropionate, tetrakis (methyl 3-laurylthiodipropionate) methane, Examples thereof include bis (2-methyl-4- (alkyl (C _{8 to} C ₁₈ alone or in mixture) thiopropionyloxy) -5-tert-butylphenyl) sulfide, 2-mercaptobenzimidazole, and a zinc salt thereof.

  Examples of ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5′-methylenebis (2-hydroxy-4-methoxybenzophenone). 2-hydroxybenzophenones; 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- ( 2′-hydroxy-3 ′, 5′-dicumylphenyl) benzotriazole, 2,2′-methylenebis ( 2- (2′-hydroxyphenyl) benzotriazoles such as tert-octyl-6-benzotriazolyl) phenol, 2- (2′-hydroxy-3′-tert-butyl-5′-carboxyphenyl) benzotriazole Phenyl salicylate, resorcinol monobenzoate, 2,4-ditertiarybutylphenyl-3,5-ditertiarybutyl-4-hydroxybenzoate, 2,4-ditertiaryamylphenyl-3,5-ditertiary Benzoates such as butyl-4-hydroxybenzoate, hexadecyl-3,5-ditert-butyl-4-hydroxybenzoate; 2-ethyl-2′-ethoxyoxanilide, 2-ethoxy-4′-dodecyloxanilide Substituted oxanilides such as ethyl-α-cyano-β, β-diphenyl acrylate, methyl-2-sia Cyanoacrylates such as -3-methyl-3- (p-methoxyphenyl) acrylate; 2- (2-hydroxy-4-octoxyphenyl) -4,6-bis (2,4-ditert-butylphenyl) -S-triazine, 2- (2-hydroxy-4-methoxyphenyl) -4,6-diphenyl-s-triazine, 2- (2-hydroxy-4-propoxy-5-methylphenyl) -4,6-bis And triaryltriazines such as (2,4-ditert-butylphenyl) -s-triazine.

  Examples of the hindered amine compound include 2,2,6,6-tetramethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 2,2,6,6- Tetramethyl-4-piperidylbenzoate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (1 -Undecyloxy-2,2,6,6-tetramethyl-4-piperidyl) carbonate, tetrakis (2,2,6,6-tetramethyl-4-piperidylbutanetetracarboxylate, tetrakis (1,2,2) , 6,6-pentamethyl-4-piperidylbutanetetracarboxylate, bis (2,2,6,6-tetramethyl-4-piperidyl) Di (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) .di (tridecyl) -1,2,3,4 Butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) -2-butyl-2- (3,5-ditert-butyl-4-hydroxybenzyl) malonate, 1- ( 2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / diethyl succinate polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) Hexane / dibromoethane polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / 2,4-dichloro-6-morpholino-s-triazine polycondensate, 1 , -Bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / 2,4-dichloro-6-tert-octylamino-s-triazine polycondensate, 1,5,8,12-tetrakis [2,4-Bis (N-butyl-N- (2,2,6,6-tetramethyl-4-piperidyl) amino) -s-triazin-6-yl] -1,5,8,12-tetra Azadodecane, 1,5,8,12-tetrakis [2,4-bis (N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino) -s-triazine-6 -Yl] -1,5,8,12-tetraazadodecane, 1,6,11-tris [2,4-bis (N-butyl-N- (2,2,6,6-tetramethyl-4- Piperidyl) amino) -s-triazin-6-ylaminoundecane, 1,6 , 11-tris [2,4-bis (N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino) -s-triazin-6-ylaminoundecane Can be given.

  Flame retardants include condensed flame retardants such as halogen flame retardants such as decabromodiphenyl ether and tetrabromobisphenol A, polyphenols such as triphenyl phosphate, resorcinol and bisphenol A, and monohydric phenols such as phenol and 2,6-xylenol. Acid esters; inorganic phosphorus compounds such as red phosphorus and melamine phosphate; nitrogen-containing flame retardants such as melamine cyanurate; inorganic flame retardants such as magnesium hydroxide and aluminum hydroxide; flame retardant aids such as antimony oxide and zirconium oxide An anti-drip agent such as polytetrafluoroethylene is used.

  Flame retardant aids include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polytetrafluoroethylene-hexafluoropropylene copolymer (FEP), and (meth) acryl-modified PTFE. For example, fluororesin and silicon resin.

Other nucleating agents include metal salts of benzoic acids such as sodium benzoate, aluminum-p-tert-butylbenzoate, lithium-p-tert-butylbenzoate; 2,2-methylenebis (4,6-ditertiary Butylphenyl) phosphate metal salts such as sodium phosphate; other benzylidene sorbitols such as dibenzylidene sorbitol, bis (4-methylbenzylidene) sorbitol, bis (4-ethylbenzylidene) sorbitol; metal alcoholates such as glycerol zinc Amino acid metal salts such as zinc glutamate; aliphatic dibasic acids having a bicyclo structure such as bicycloheptanedicarboxylic acid or salts thereof and metal salts thereof, aromatic sulfones such as sodium benzenesulfonate and lithium p-toluenesulfonate Such as acid metal salt, and the like.
The present invention provides an effect equivalent to that of a finely pulverized product even when the dibenzylidene sorbitol compound of the general formula (I) particularly excellent in imparting transparency is used without being finely pulverized. Using the same together reduces the effect of the present invention because the effect of improving the transparency is smaller than the amount added. 2,2-methylenebis (4,6-ditertiarybutylphenyl) Phosphoric acid ester such as sodium phosphate metal salt such as sodium salt as well as transparency, as well as the glass transition temperature of polypropylene resin The combined use with an improving nucleating agent is preferable because an effect that cannot be obtained by the present invention alone can be expected.

  Examples of heavy metal deactivators include 2-hydroxybenzamide-N-1H-1,2,4-triazol-3-yl and dodecanedioic acid bis [2- (2-hydroxybenzoyl) hydrazide]. It is done.

  As the hydrotalcite compound, a double salt compound composed of magnesium and aluminum or a double salt compound composed of magnesium, zinc and aluminum represented by the following general formula (II) is preferably used, and the crystal water is dehydrated. It may be.

Mg _x1 Zn _x2 Al _2. (OH) _{2 (x1 + x2) +4.} (CO ₃ ) _{1-y1 /} 2.mH ₂ O (II)
(In the formula, x1, x2 and y1 each represent a number satisfying the condition represented by the following formula, and m represents 0 or an arbitrary integer.
0 ≦ x2 / x1 ≦ 10, 2 ≦ x1 + x2 <20, 0 ≦ y1 ≦ 2)

  The hydrotalcite compound may be a natural product or a synthetic product. Examples of methods for synthesizing the synthetic products include Japanese Patent Publication No. 46-2280, Japanese Patent Publication No. 50-30039, Japanese Patent Publication No. 51-29129, Japanese Patent Publication No. 3-36839, Japanese Patent Publication No. Sho 61-174270, Publicly known synthesis methods described in JP-A Nos. 2001-164042 and 2002-53722 can be exemplified. In the present invention, the hydrotalcite compound can be used without being limited by its crystal structure, crystal particle size, etc., and the residual amount of heavy metals such as iron contained in the raw material is purified. It is preferable that the cost is low within a practical range.

  As the hydrotalcite compound, the surface thereof is higher fatty acid such as stearic acid, higher fatty acid metal salt such as alkali metal oleate, organic sulfonic acid metal salt such as alkali metal dodecylbenzenesulfonate, higher fatty acid amide, Those coated with higher fatty acid esters or waxes can also be used.

  The method of blending the clarifying agent composition of the present invention into a resin such as a polyolefin resin, the molding method of the blended resin composition, and the use are not particularly limited, and extrusion molding, injection molding, blow, calendar, press molding, vacuum Used and used as a film, sheet, molded product, etc. for automotive interior / exterior materials, home appliances, building materials, packaging materials, agricultural materials, miscellaneous goods, medical instruments, etc. using known molding techniques such as molding The form can be used alone or with another resin or metal directly or via an adhesive layer.

Synthesis Example (Synthesis of a dibenzylidene sorbitol compound represented by the general formula (I))
To a four-necked flask for reaction, 44 g (0.42 mol) of 3,4-dimethylbenzaldehyde, 38 g (0.21 mol) of sorbitol, 5 g of 50% sulfuric acid as a catalyst, 700 ml of cyclohexane and 70 ml of methanol as a solvent were added, and the methanol reflux temperature was added. Stir. Methanol of the same amount as the amount of methanol to be volatilized is dropped at any time, and a mass is obtained in 5 hours of reaction.
The obtained lump is washed with isopropyl alcohol / water = 1/1 (volume ratio), and the filtrate is dried at 90 ° C. under reduced pressure.

The resulting mass was pulverized with a pulverizer to obtain dibenzylidene sorbitol powder having a d ₉₇ according to Table 1 (Table 1 sorbitol abbreviated), respectively. Dibenzylidene sorbitol powder d ₉₇ was measured by laser light scattering. Moreover, blocking property was evaluated by the angle of repose measurement by the powder tester about the obtained dibenzylidene sorbitol powder. The angle of repose of each dibenzylidene sorbitol powder is shown in Table 1. A larger angle of repose indicates poorer fluidity.

Examples 1-5 and Comparative Examples 1-3
Dibenzylidene sorbitol powder (abbreviated as sorbitol in Table 1) and tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] methane powder (in Table 1) obtained in the synthesis example A clearing agent composition was prepared by mixing phenol and abbreviation: ADEKA STAB AO-60 manufactured by ADEKA Co., Ltd.) according to the formulation shown in Table 1.
These clearing agent compositions were blended into a polypropylene resin as follows to prepare test pieces. In Comparative Example 3, dibenzylidene sorbitol powder and tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] methane powder were prepared without preparing a clarifying agent composition. And other resin additives are blended directly into a polypropylene resin.

  To 100 parts by mass of random polypropylene (MFI = 8 to 10 g / 10 min: MG3: manufactured by Nippon Polypro Co., Ltd.), tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] 0.1 parts by mass of methane, 0.05 parts by mass of tris (2,4-di-tert-butylphenyl) phosphite, 0.05 parts by mass of calcium stearate, and 0.3 of the clarifying agent composition described in Table 1 A mass part was mix | blended, it mixed with the Henschel mixer, and it extrusion-molded with the twin-screw extruder (made by Ikegai Co., Ltd., PCM-30), and obtained the pellet. The obtained pellet was injection-molded at 250 ° C. to prepare a test piece having a thickness of 1 mm.

  Using the melt indexer (manufactured by Toyo Seiki Co., Ltd.), the obtained pellets were measured for melt flow index (MFI) at 230 ° C. under a 2.16 kg load according to JIS K 7210, and evaluated for the presence or absence of deterioration in resin physical properties. did. The larger the MFI, the greater the change in physical properties of the resin, which is not preferable. Moreover, according to JIS K 7361-1, the transparency (haze) of a test piece was measured and the transparency improvement effect was measured. The smaller the value of Haze, the better the transparency. These results are shown in Table 1.

From the results shown in Table 1, the following is clear. The polypropylene resin compositions of Examples 1 to 5 blended with the clearing agent composition of the present invention are excellent in transparency and have no deterioration in physical properties. In contrast, the polypropylene resin composition of Comparative Example 1 was blended clarifying agent composition using dibenzylidene sorbitol powder d ₉₇ is smaller in particle size, the physical properties of those excellent in transparency is lowered. Moreover, the polypropylene resin composition of Comparative Example 2 in which a clarifying agent composition composed of dibenzylidene sorbitol powder alone is inferior in transparency and greatly deteriorated in physical properties. Furthermore, the polypropylene resin composition of Comparative Example 3 in which dibenzylidene sorbitol powder and tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] methane powder were directly blended, The result is greatly inferior in transparency.

Claims (3)

100 parts by mass of a dibenzylidene sorbitol compound represented by the following general formula (I) having a particle size of d ₉₇ of 31 μm or more and 200 μm or less, and tetrakis [3 (3,5-di-tert-butyl-4- Hydroxyphenyl) propionyloxymethyl] is a mixture with 10 to 200 parts by mass of methane, and the total of both components is 50% by mass or more of the mixture, and the mixture is obtained by mixing the components using a mixing device. A clearing agent composition.

General formula (I) in d ₉₇ of dibenzylidene sorbitol compound 40μm or represented, and, clarifying agent composition according to claim 1, wherein at 100μm or less. 100 parts by mass of a dibenzylidene sorbitol compound represented by the following general formula (I) having a particle size of d ₉₇ of 31 μm or more and 200 μm or less, and tetrakis [3 (3,5-di-tert-butyl-4- Hydroxyphenyl) propionyloxymethyl] A method for producing a clarifying agent composition that is a mixture of 10 to 200 parts by mass of methane, and the total of both components is 50% by mass or more of the mixture, wherein the components are mixed A method for producing a clarifying agent composition, comprising mixing using