JPH0627212B2 - Expandable styrene resin particles and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to expandable styrene resin particles and a method for producing the same. More specifically, in the production of a molded product having a cell structure, foamed particles in the molding process are completely fused at the boundary surface thereof, and a foamed product capable of producing a molded product having as few particle gaps as possible. Styrene-based resin particles and a method for producing the same.

[Conventional technology and problems]

The expandable styrenic resin particles are, for example, polystyrene resin particles impregnated with a foaming agent, that is, an easily volatile aliphatic hydrocarbon which only swells the particles slightly, such as n-pentane, in an aqueous suspension, or Alternatively, it is produced by impregnating polystyrene resin particles with a blowing agent such as butane or propane which is gaseous at room temperature at room temperature together with a small amount of a solvent such as toluene or cyclohexane in an aqueous suspension.

The expandable styrene-based resin particles produced in this manner are used as a raw material for producing a foamed styrene-based resin molded body. In order to industrially and economically produce a foamed styrene resin molded article, expandable styrene resin particles are made into pre-expanded particles by steam or the like, and the pre-expanded particles are provided with a large number of small holes on a wall having a desired shape. It is filled in a closed mold that has been punched, and a heating medium such as water vapor is jetted through the small holes in the mold to heat it to a temperature above the softening point of the pre-expanded particles, and the two are melted and then melted. The method of taking out from the mold is common.

The expandable styrenic resin particles produced as described above are aggregated and agglomerated in the pre-expansion step, and thus obstruct the particle transfer pipe or the molding die filling hole, which becomes an obstacle. In order to prevent this, a method of coating the expandable styrenic resin particles in advance with a surface of, for example, metal soap, talc powder or wax is used.
Pre-expanded particles of expandable styrenic resin particles surface-coated by these methods are difficult to completely fill the voids in the mold cavity during molding, and foaming is suppressed by the accumulation of drainage of steam generated during heating. The resulting molded body has a large amount of water immediately after molding without mutual fusion of particles, and furthermore, the porosity is high because the pre-expanded particles in the vicinity of the mold wall surface are poorly filled. There is a problem that a large amount of drainage is generated in the part, and particle gaps are generated on the surface of the molded body.

The molded product thus obtained needs to be sufficiently dried, for example, when it is used as a packaging material for electric products. In addition, there is a defect that dust is adsorbed due to electrification of the molded body. In order to deal with the problem caused by charging, a method has been adopted in which a cationic surfactant is added at the time of pre-expansion of the expandable styrenic resin particles, or added after the pre-expansion to prevent the molded product from being charged. However, in this case, the moldability of the pre-expanded particles in the mold is not sufficient, molding defects are likely to occur, and a decrease in productivity cannot be avoided. Furthermore, since the foaming of the molded body is not sufficient, the appearance is poor and the value as a packaging material is impaired.

[Means for solving problems]

The inventors of the present invention aim to eliminate the above-mentioned drawbacks of the prior art, and cells in which foamed particles in the molding process are completely fused at the boundary surface thereof and the particle gap is as small as possible. The present invention has been completed as a result of intensive research to obtain a molded product having a structure and free of adsorption of dust due to electrification.

That is, the first aspect of the present invention is that the surface of the expandable styrenic resin particles containing 1 to 20 parts by weight of the foaming agent relative to 100 parts by weight of the styrene resin particles has a nonionic interface with respect to 100 parts by weight of the resin particles. Activators, oxyethylene / oxypropylene block polymers and solubility parameters (Solu
at least one selected from organic compounds that are oily liquids at room temperature with a bility parameter (hereinafter referred to as SP value) of 8 or less.
It is coated with 0.01 to 0.3 parts by weight and 0.001 to 0.3 parts by weight of a cationic surfactant, the surface-adhered water content is 0.5% by weight or less, and the escape rate of the contained foaming agent is 3 to 40% by weight. The second characteristic of the present invention is that the surface of the expandable styrenic resin particles containing 1 to 20 parts by weight of the foaming agent is added to 100 parts by weight of the styrene resin particles. Below, the resin particles 10
0.01 to 0.3 parts by weight of at least one kind selected from nonionic surfactants, oxyethylene / oxypropylene block polymers, and organic compounds which are oily liquids at room temperature with SP value of 8 or less, and cationic surfactants per 0 parts by weight. 0.001 ~
Expandable styrenic resin particles, characterized in that, after being coated with a mixture with 0.3 part by weight, the water content adhering to the surface of the coated resin particles is removed, and a drying treatment is carried out to disperse 3 to 40% by weight of the contained blowing agent. In the third method of the present invention, the surface of expandable styrenic resin particles containing 1 to 20 parts by weight of a foaming agent is added to 100 parts by weight of styrene resin particles in the presence of water. 10
To 0 part by weight, 0.001 to 0.3 part by weight of at least one selected from nonionic surfactants, oxyethylene / oxypropylene block polymers, and organic compounds that are oily liquids at room temperature with an SP value of 8 or less is coated, then After coating with 0.001 to 0.3 parts by weight of a cationic surfactant, the water adhering to the surface of the coated resin particles is removed to obtain 3 to 40% by weight of the foaming agent.
And a method for producing expandable styrenic resin particles, each of which is characterized by performing a drying treatment to disperse the styrene.

The expandable styrenic resin particles in the present invention are resin particles obtained by polymerizing by adding a foaming agent at the time of polymerization, or impregnated after the polymerization, and for example, a polymer of styrene alone or other polymer containing styrene as a main component. Polymer particles that can be foamed by heating by preliminarily containing a foaming agent which is liquid or gaseous at room temperature during polymerization in a copolymer with a vinyl monomer or impregnated after polymerization. Of course, the additives usually used may be contained.

As the foaming agent in the present invention, an easily volatile hydrocarbon having a boiling point lower than the softening point of the resin particles is used, and those which do not dissolve or slightly swell the resin particles are preferable, and one or two kinds are preferable. Used in the above mixture. The foaming agent is, for example, propane, butane, pentane or one containing them as a main component, and a part of them may be replaced with hexane, heptane, cyclohexane, methyl chloride, freon or the like and used. The amount of the foaming agent is 1 to 20 with respect to 100 parts by weight of the styrene resin particles.
Parts by weight.

As the nonionic surfactant used as a coating agent in the present invention, polyoxyethylene alkyl ether,
Examples thereof include ether type such as polyoxyethylene alkylphenol ether, and ester type such as polyoxyethylene alkyl ester, sorbitan alkyl ester, and polyoxyethylene sorbitan alkyl ester. Nonionic surfactants belonging to these include, for example, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene beef fatty acid ether, polyoxyethylene octylphenol ether, and polyoxyethylene octylphenol ether. Oxyethylene nonylphenol ether, polyoxyethylene octylphenol ether, polyoxyethylene laurate, polyoxyethylene palmitate, polyoxyethylene stearate, polyoxyethylene oleate, polyoxyethylene beef fatty acid ester, sorbitan monolaurate,
Sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan trioleate, sorbitan monobehenate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monomonoate Examples thereof include palmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate and the like, and these may be used as a mixture.

The oxyethylene / oxypropylene block polymer used as a coating agent in the present invention is not particularly limited with respect to the average molecular weight of polypropylene glycol and the polyethylene oxide content in the product, but a water-soluble one is preferable. For example, an oxyethylene / oxypropylene block polymer having an average molecular weight of polypropylene glycol of 1000 to 2000 and polyethylene oxide of 20 to 80% by weight can be mentioned, and it is acceptable to mix and use these.

The organic compound that is an oily liquid at room temperature used as a coating agent in the present invention has an SP value of 8 or less. When the SP value exceeds 8, the resin particles are cracked and cannot be used for the purpose of the present invention. As an organic compound that is an oily liquid at room temperature with an SP value of 8 or less, liquid paraffin with a kinematic viscosity of 7 to 95 cSt / 40 ° C., or a general formula (In the formula, R _{1 to} R ₄ represent a hydrogen atom, a methyl group or a phenyl group, and R _{5 to} R ₁₀ represent a methyl group or a phenyl group.
m and n represent an integer of 1 or more. ) Silicone oils represented by), for example, one or more oil-type or emulsion-type mixtures of dimethylsiloxane, diphenylsiloxane, and methylphenylsiloxane. still,
For the SP value measurement and calculation method, refer to "Polymer Handbook, A Wiley-Interscience Publicatio
n-publishing) ”, IV-337.

The nonionic surfactant, the oxyethylene / oxypropylene block polymer and the organic compound having an SP value of 8 or less at room temperature which is an oily liquid are mixed alone or in an arbitrary ratio as they are, or as an aqueous solution, a water dispersion or a water emulsion. Used as a liquid. The coating agent is used in an amount of 0.01 to 0.3 parts by weight based on 100 parts by weight of the expandable styrene resin particles. 0.0
If it is less than 1 part by weight, the effect of smoothing the surface of the molded product is not sufficient, and if it exceeds 0.3 part by weight, the grain boundaries on the surface of the molded product are in a molten state and the appearance is poor.

Examples of the cationic surfactant used as the coating agent in the present invention include alkylamine salts and quaternary ammonium salts. Examples of the cationic surfactants belonging to these include, for example, octadecylamine acetate, stearylamine acetate, Stearylamine hydrochloride, octadecyltrimethylammonium chloride, alkyl (beef tallow) trimethylammonium chloride, dodecyltrimethylammonium chloride, alkyl (coconut) trimethylammonium chloride, hexadecyltrimethylammonium chloride, alkyl (coconut) dimethylbenzylammonium chloride, oxyethylenedodecylamine , Polyoxyethylene alkylamine, N-
Examples thereof include hydroxyethyl-N (2-hydroxyalkyl) amine, and it is safe to use a mixture of two or more thereof.

Cationic surfactant is 0.00 relative to 100 parts by weight of resin particles.
Used in the range of 1 to 0.3 parts by weight. If it is less than 0.001 part by weight, the antistatic effect at the time of the dispersal treatment of the foaming agent contained in the expandable styrenic resin particles and the antistatic effect of the molded article are not sufficient. It is uneconomical because it is eluted in the drain and the antistatic effect is not further improved. The cationic surfactant may be mixed with the above-mentioned nonionic surfactant, oxyethylene / oxypropylene block polymer, and an organic compound which is an oily liquid at room temperature and has an SP value of 8 or less to coat the surface of the resin particles. After coating, the latter may be coated.

The coating agent is coated on the surface of the resin particles in the presence of water. As a method for coating in the presence of water, an aqueous solution of a coating agent, a water dispersion (suspension) solution or a water emulsion is prepared, and resin particles are added thereto, and a water dispersion (suspension) of resin particles is carried out. There are a method of adding a coating agent to a liquid, a method of directly adding a coating agent to resin particles to which water is attached, and the like. For example, there may be mentioned a method of thoroughly mixing the aqueous solution of the resin particles and the coating agent, the aqueous dispersion or the water emulsion with a blender or the like. In this case, the resin particles may be impregnated and coated with zinc stearate, talc, calcium carbonate or the like agglomerating inhibitor during pre-expansion, water repellent or the like after the coating treatment. As another coating method, resin particles impregnated with a foaming agent in an aqueous suspension are used, for example, after being dehydrated by a centrifugal dehydrator or the like, and are still undried, and a coating agent or an aqueous solution thereof, or a water dispersion on the surface thereof. A method of adhering the liquid or water emulsion using a blender or the like is also advantageous. If the surface of the particles is coated with a coating agent in the absence of water, uneven coating occurs, resulting in a molded article having a partially blackish color unevenness. On the other hand, when the coating is carried out with a system in which water is present, uniform coating is achieved and a good molded product is obtained. Moreover, surprisingly, the surface moisture after coating
Dry to 0.5% by weight or less, preferably 0.1% by weight or less, and further 3 to 40% by weight, preferably 6% by weight of the contained foaming agent.
It has been found by the present inventors that the surface of the molded body has no particle gap and exhibits an excellent appearance by performing the dissipating treatment of 25 wt%. If the surface water content exceeds 0.5% by weight, particle voids appear on the surface of the molded product, resulting in poor appearance. Further, when the content of the foaming agent contained is less than 3% by weight, the effect of smoothing the surface of the molded body is not sufficient, and when it exceeds 40% by weight, the grain boundary on the surface of the molded body is depressed and the appearance is poor. Becomes

There is no particular limitation on the method of drying the water attached to the expandable styrenic resin particles together with the coating agent.

There are various methods for removing the foaming agent contained in the expandable styrenic resin particles that have been coated with a coating agent to remove the attached water. For example, the foaming agent contained can be dissipated by a groove-type or cylinder-type stirring dryer, a box-type or band-type aeration dryer, a fluidized-bed dryer and the like. The treatment temperature is lower than the foaming temperature of the expandable styrenic resin particles, and is preferably 35 ° C. or higher from the viewpoint of productivity. The escape amount of the contained foaming agent can be adjusted by the treatment temperature and the treatment time.

Further, by using the dryer or the like, it is possible to simultaneously remove the water adhered to the coated resin particles and dissipate the contained foaming agent.

The water content on the resin particle surface can be measured by a Karl Fischer water content meter using a methanol dehydrated solvent. The amount of the foaming agent contained in the resin particles can be measured by a scattering method using a soaking dryer or the like.

[Action / effect]

According to the present invention, it is possible to provide an excellent molded product in which foamed particles are completely fused to each other and there is substantially no particle gap, and dust is not adsorbed after the molded product is dried.

The reason why such an excellent molded product can be obtained by the present invention is not necessarily clear, but the penetration of the coating agent to the surface portion of the expandable styrenic resin particles during the drying of water and the foaming of the surface portion containing the foamed material. It is considered that this is because the cell film on the surface of the pre-expanded particles was thickened due to the composition change of the surface portion due to the agent escape and the heat resistance was increased.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 100 parts by weight of styrene monomer, 110 parts by weight of water, 0.15 parts by weight of tricalcium phosphate, sodium dodecylbenzenesulfonate in a pressure resistant reactor equipped with a stirrer and a temperature detecting tube.
005 parts by weight, 0.25 parts by weight of benzoyl peroxide, and 0.1 parts by weight of tert-butyl perbenzoate were added, and the temperature was raised to 90 ° C. under pressure of 0.5 kg / cm ^{2 of} nitrogen while stirring, and polymerization was carried out for 5 hours.

Next, 1.8 parts by weight of cyclohexane and 8.5 parts by weight of butane were added and the temperature was raised to 105 ° C. to impregnate the foaming agent for 6 hours. This was cooled to room temperature to obtain a spherical expandable polystyrene resin particle. The resin particles are dried and then sieved to 1
Obtain particles of 4-20 mesh, then zinc stearate
0.09 parts by weight was added, stirred with a ribbon blender, and then taken out.

Expandable polystyrene resin particles 100 obtained by the above method
To the parts by weight, a mixed aqueous solution or water dispersion of a nonionic surfactant and a cationic surfactant shown in Table 1 was added and stirred in a container to uniformly coat each coating agent on the surface of the resin particles, Drying was carried out at an exhaust air temperature of 40 ° C using a dryer, and then the foaming agent contained in the box-type aeration dryer was treated for 20 minutes at a temperature of 40 ° C to disperse, and the expandable polystyrene resin coated with the above-mentioned coating agent. The particles were obtained. Table 1 and Table 6 show the surface water content and the rate of escape of the blowing agent.

In addition, in Tables 1 and 6, the HLB value is a hydrophilic-lipophilic equilibrium value (Hydrophile-Lipophile Balance value).

The rate of escape of the blowing agent was determined by dividing the difference between the amount of the blowing agent before treatment and the amount of the blowing agent after treatment by the amount of the blowing agent before treatment.

The expandable polystyrene resin particles obtained were heated by steam in a batch type pre-expanding machine to obtain pre-expanded particles having an apparent volume of about 60 times.

After curing and drying the pre-expanded particles in the atmosphere for 24 hours,
Pearl Star 90 automatic molding machine (manufactured by Toyo Kikai Kinzoku Co., Ltd.)
Then, it was molded using a mold having a cavity size of 300 mm × 450 mm × 20 mm. The internal melting rate, internal state, surface state, internal water content, and antistatic property of the obtained molded product are shown in Tables 1 and 6.

In Tables 1 and 6, the internal fusion rate indicates the fusion rate between the foam particles on the fracture surface of the molded body, and the boundary between the foam particles in the fracture surface when the molded body is torn. It was expressed as a ratio (%) to the total number of particles that were not separated on the surface but were torn inside the expanded particles.

The internal state was obtained by observing the particle gap state of a flat plate obtained by cutting the center of the molded body into 300 mm × 450 mm × 5 mm. ⊚ means no gap, ◯ means a little gap, and Δ means a gap.

The surface condition indicates the smoothness of the surface and the state of the interstices between the particles, and ⊚ means excellent, ∘ means good, Δ means slightly bad, and × means bad.

The internal water content was determined by dividing the difference between the weight of the molded body immediately after molding and the weight after drying at 40 ° C. for 24 hours by the weight after drying.

The antistatic property was judged by rubbing the dried molded product with wool 20 times, and then bringing it closer to tobacco ash and measuring the distance at which adsorption started. ◯ means 1 cm or less, Δ means 1-2 cm, and x means 2 cm or more.

Example 2 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were coated with a mixed aqueous solution or aqueous dispersion of an oxyethylene / oxypropylene block polymer and a cationic surfactant shown in Table 2, dried and contained. The dispersal treatment of the foaming agent was performed. Pre-foaming and molding were performed in the same manner as in Example 1. The results are shown in Table 2.

Example 3 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were coated with a mixed aqueous dispersion of liquid paraffin and a cationic surfactant shown in Table 3 in the same manner as in Example 1, dried and dried. Dispersion treatment of the contained foaming agent was performed. Pre-foaming and molding were performed in the same manner as in Example 1. The results are shown in Table 3.

Example 4 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were coated with a mixed aqueous dispersion of silicone oil and a cationic surfactant shown in Table 4 in the same manner as in Example 1 and then dried. And the dispersal treatment of the contained foaming agent was performed. Pre-foaming and molding were performed in the same manner as in Example 1. The results are shown in Tables 4 and 6.

Example 5 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were added to sorbitan monooleate (HLB value 4.3), oxyethylene / oxypropylene block polymer (polypropylene glycol average molecular weight 2000, poly Ethylene oxide 10% by weight), liquid paraffin (kinematic viscosity 14.5 cSt / 40 ° C.) and dimethylsiloxane at a ratio of 1: 1 each with a 5% by weight mixed aqueous solution or aqueous dispersion (coating agent A) of 1 part by weight, and then After coating 0.3 parts by weight of a 10% by weight aqueous solution of N-hydroxyethyl-N (2-hydroxyalkyl) amine (coating agent B), drying and contained blowing agent escape treatment were carried out. Pre-foaming and molding were performed in the same manner as in Example 1. The results are shown in Table 5.

Example 6 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were added to polyoxyethylene cetyl ether (HLB value 11.9) and oxyethylene / oxypropylene block polymer (polypropylene glycol average molecular weight) in the same manner as in Example 1. 1000, polyethylene oxide 20% by weight), liquid paraffin (kinematic viscosity 14.5 cSt / 40 ° C) and dimethyl siloxane with octadecyl trimethyl.
After coating 0.05 parts by weight of a coating agent in which ammonium chloride was mixed at a ratio of 1: 1, the dispersal treatment of the contained blowing agent was performed in the same manner as in Example 1. Pre-foaming and molding is in Example 1
The same method was used. The results are shown in Tables 1, 2, 3 and 4.

Example 7 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were mixed with 1: 1 of polyoxyethylene oleyl ether (HLB value 15.4) and octadecyl trimethyl ammonium chloride in the same manner as in Example 1. 5% by weight mixed aqueous solution and 1: 1 of methylphenylsiloxane and octadecyl trimethyl ammonium chloride.
After coating 1 part by weight of each 5 wt% mixed aqueous solution at a ratio of 1, water was removed at an exhaust air temperature of 40 ° C. using an airflow dryer, and then 30 ° C., 50 ° C. and 60 ° C. by a box-type ventilation dryer. The included blowing agent escape treatment was carried out at 20 ° C. for 20 minutes and 50 ° C. for 2 hours, respectively. Pre-foaming and molding were performed in the same manner as in Example 1. The results are shown in Table 6.

Example 8 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were added to oxyethylene / oxypropylene block polymer (polypropylene glycol average molecular weight 2000, polyethylene oxide 40% by weight) and dodecyl trimethyl in the same manner as in Example 1.・ 5% by weight mixed aqueous solution of ammonium chloride at a ratio of 1: 1 and 5% by weight mixed aqueous dispersion of liquid paraffin (kinematic viscosity 7.3 cSt / 40 ° C) and octadecylamine acetate at a ratio of 1: 1 respectively. After coating 1 part by weight, a box-type aeration dryer was used for 3 days at 40 ° C.
Moisture removal and blowing agent escape treatment at 40 ° C. for 30 minutes at 0 ° C. and in a fluidized bed dryer were performed simultaneously. Pre-foaming and molding were performed in the same manner as in Example 1. The sixth result
Shown in the table.

Comparative Example 1 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were added to polyoxyethylene stearyl ether (HLB value 14.2) and oxyethylene / oxypropylene block polymer (polypropylene glycol average molecular weight 1000) in the same manner as in Example 1. , Polyethylene oxide 40% by weight), liquid paraffin (kinematic viscosity 14.5 cSt / 40 ° C.) and dimethyl siloxane each mixed with oxy ethylene dodecyl amine at a ratio of 1: 1 to prepare a 5% by weight aqueous solution or dispersion. Pre-foaming and molding were carried out in the same manner as in Example 1 without performing the drying and the dispersal treatment of the contained foaming agent, each coated with 1 part by weight. The results are shown in Table 1, Table 2, Table 3, and Table 4, respectively.

Comparative Example 2 100 parts by weight of the expandable polystyrene resin particles obtained in Example 1 were mixed with polyoxyethylene sorbitan monostearate (HLB value 14.9), oxyethylene / oxypropylene block polymer (polypropylene glycol average molecular weight 2000, polyethylene oxide). 40% by weight),
Liquid paraffin (kinematic viscosity 14.5 cSt / 40 ° C) and methylphenylsiloxane were mixed with oxy-ethylene-dodecyl-amine at a ratio of 1: 1 to give a mixture of 0.
05 parts by weight were coated, and prefoaming and molding were performed in the same manner as in Example 1. The results are shown in Tables 1, 2, 3 and 4.

Comparative Example 3 The expandable polystyrene resin particles obtained in Example 1 were immediately subjected to prefoaming and molding in the same manner as in Example 1 without performing coating with a coating agent, removal of water and dissipation treatment of the contained blowing agent. . The results are shown in Tables 1, 2, 3 and 4.

Claims (31)

[Claims] 1. The surface of expandable styrenic resin particles containing 1 to 20 parts by weight of a foaming agent relative to 100 parts by weight of styrene resin particles has 100% by weight of the resin particles and a nonionic surfactant, oxy Ethylene / oxypropylene block polymers and solubility parameters (Solubility Param
eter, hereinafter referred to as SP value) is 8 or less and 0.01 to 0.3 parts by weight of at least one kind selected from organic compounds that are oily liquids at room temperature and 0.001 to 0.3 parts by weight of a cationic surfactant are coated, and the surface-adhered water content is Is 0.5% by weight or less, and the escape rate of the contained foaming agent is 3 to 40% by weight, and expandable styrenic resin particles. 2. The resin particles according to claim 1, wherein the nonionic surfactant is at least one ether type nonionic surfactant selected from polyoxyethylene alkyl ethers and polyoxyethylene alkylphenol ethers. 3. A polyoxyethylene alkyl ether is at least one selected from polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether and polyoxyethylene beef fatty acid ether. The resin particle according to claim 2. 4. The resin particles according to claim 2, wherein the polyoxyethylene alkylphenol ether is at least one selected from polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether. 5. The nonionic surfactant according to claim 1, wherein the nonionic surfactant is at least one ester type nonionic surfactant selected from polyoxyethylene alkyl ester, sorbitan alkyl ester and polyoxyethylene sorbitan alkyl ester. Resin particles. 6. The resin particles according to claim 5, wherein the polyoxyethylene alkyl ester is at least one selected from polyoxyethylene laurate, polyoxyethylene palmitate, polyoxyethylene stearate and polyoxyethylene oleate. . 7. A sorbitan alkyl ester from sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan trioleate and sorbitan monobehenate. The resin particles according to claim 5, which is at least one kind selected. 8. The polyoxyethylene sorbitan alkyl ester is at least selected from polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate. The resin particles according to claim 5, which is one kind. 9. An organic compound having a kinematic viscosity at 40 ° C. of 7 to 9
The resin particles according to claim 1, which are liquid paraffin of 5 cSt. 10. The organic compound has the general formula _(Wherein, R 1 to R ₄ represents a hydrogen atom, a methyl group or a phenyl _group, .m R 5 to R ₁₀ is showing a methyl group or a phenyl group, n represents an integer of 1 or more.) Expressed in The resin particles according to claim 1, which are at least one kind of silicone oil. 11. The resin particle according to claim 1, wherein the cationic surfactant is at least one alkylamine salt selected from monoalkylamine salts and dialkylamine salts. 12. The resin particles according to claim 1, wherein the cationic surfactant is at least one quaternary ammonium salt selected from monoalkyl ammonium salts and dialkyl ammonium salts. 13. The resin particles according to claim 1, wherein the water content adhering to the surface is 0.1% by weight or less. 14. The resin particles according to claim 1, wherein the escape rate of the contained foaming agent is 6 to 25% by weight. 15. The surface of expandable styrene resin particles containing 1 to 20 parts by weight of a foaming agent relative to 100 parts by weight of styrene resin particles in the presence of water.
Nonionic surfactant, oxyethylene.
0.01 to 0.3 part by weight of at least one selected from oxypropylene block polymers and organic compounds which are oily liquids at room temperature with SP value of 8 or less, and a cationic surfactant 0.001 to 0.
After being coated with a mixture with 3 parts by weight, the expandable styrene resin particles are characterized by being subjected to a drying treatment to remove water adhering to the surface of the coated resin particles and dissipate 3 to 40% by weight of the contained blowing agent. Manufacturing method. 16. The surface of expandable styrenic resin particles containing 1 to 20 parts by weight of a foaming agent with respect to 100 parts by weight of styrene resin particles in the presence of water.
Nonionic surfactant, oxyethylene.
The oxypropylene block polymer and at least one kind selected from organic compounds which are oily liquids at room temperature having an SP value of 8 or less are coated with 0.01 to 0.3 part by weight, and then with 0.001 to 0.3 part by weight of a cationic surfactant. A method for producing expandable styrene-based resin particles, which comprises performing a drying treatment to remove water adhering to the surface of the coated resin particles and disperse 3 to 40% by weight of the contained foaming agent. 17. The nonionic surfactant is at least one ether type nonionic surfactant selected from polyoxyethylene alkyl ethers and polyoxyethylene alkylphenol ethers.
The manufacturing method described. 18. The polyoxyethylene alkyl ether is at least one selected from polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether and polyoxyethylene beef fatty acid ether. The manufacturing method according to claim 17. 19. The method according to claim 17, wherein the polyoxyethylene alkylphenol ether is at least one selected from polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether. 20. The nonionic surfactant is at least one ester type nonionic surfactant selected from polyoxyethylene alkyl ester, sorbitan alkyl ester, and polyoxyethylene sorbitan alkyl ester. 16. The manufacturing method according to 16. 21. At least one polyoxyethylene alkyl ester selected from polyoxyethylene laurate, polyoxyethylene palmitate, polyoxyethylene stearate and polyoxyethylene oleate.
The production method according to claim 20, which is a seed. 22. Sorbitan alkyl ester is sorbitan monolaurate, sorbitan monomyristate,
21. The method according to claim 20, which is at least one selected from sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan trioleate and sorbitan monobehenate. 23. At least the polyoxyethylene sorbitan alkyl ester is selected from polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate. 21. The manufacturing method according to claim 20, which is one kind. 24. The organic compound has a kinematic viscosity of 7 to 95 cSt / 40 ° C.
The production method according to claim 15 or 16, which is liquid paraffin. 25. The organic compound has the general formula _(Wherein, R 1 to R ₄ represents a hydrogen atom, a methyl group or a phenyl _group, .m R 5 to R ₁₀ is showing a methyl group or a phenyl group, n represents an integer of 1 or more.) Expressed in The method according to claim 15 or 16, which is at least one kind of silicone oil. 26. The method according to claim 15 or 16, wherein the cationic surfactant is at least one alkylamine salt selected from monoalkylamine salts and dialkylamine salts. 27. The method according to claim 15 or 16, wherein the cationic surfactant is at least one quaternary ammonium salt selected from monoalkyl ammonium salts and dialkyl ammonium salts. 28. The method according to claim 15, wherein the water content adhering to the surface of the coated resin particles is 0.1% by weight or less. 29. The method according to any one of claims 15 to 28, wherein 6 to 25% by weight of the blowing agent containing the coated resin particles is dispersed. 30. The coating resin particles are dried to reduce the amount of water adhering to the surface to 0.5% by weight or less, and then the dissipating treatment of the blowing agent contained is carried out at a temperature lower than the foaming temperature of the resin particles. The manufacturing method described. 31. The removal of water adhering to the surface of the coated resin particles and the escape treatment of the foaming agent contained therein are carried out at the same time.
6. The manufacturing method according to 6.