JPH06114256A - Granulated powder and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Objective] The object of the present invention is to prevent dust scattering during handling, that is, to prevent environmental pollution. When using a powder granulated product in an injection molding machine or an extrusion molding machine, It is an object of the present invention to provide a powder granulated product which can be used efficiently without causing a bridge phenomenon in the hopper of a molding machine, and further does not contain a granulation auxiliary agent such as wax, and a method for producing the same. [Structure] The powder granulated product according to the present invention has a specific surface area of 50 m.
² / g or more, a bulk specific gravity of 0.2 or less, a powder granulated product made of the following raw material fine powder having an average particle diameter 300Emumyu, bulk density 0.2 to 0.8 g / cm ^3, average particle size 50 4500μ
m and rotation strength is 2.0% or less,
The powder granulated product can be obtained by granulating using a volatile granulating aid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is effective from the viewpoint of preventing scattering during handling of powder and preventing environmental pollution, and when using an injection molding machine, an extrusion molding machine, etc., in the popper or screw part of the molding machine. The present invention relates to a powder granulated product which does not cause a bridging phenomenon and further does not contain a granulating aid such as wax and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, in order to improve the handleability of powder, it has been attempted to granulate by various methods.

For example, in Japanese Patent Laid-Open No. 55-28794, a powder such as an organic pigment is mixed with a granulation aid, and the granulation aid is heated to spin granulate in a softened state. A heat rolling granulation method is disclosed. However, this granulation method mainly targets organic pigments, and when this method is applied to powders with an average particle size of 0.8 μm or less, the specific surface area is large, so that 40% by weight or more of the powder is usually used. Granulation cannot be performed unless a granulation aid of about 50% by weight is added. That is, when the granulation aid is dissolved by heat, its dispersion is poor, the binding force is weakened, more granulation aid is required, and a large amount of granulation aid is used. If it is excessively softened, the adherence to the granulator becomes severe and uniform granulation becomes difficult.

In Japanese Patent Publication No. 57-47699, an aqueous phase in which a finely dispersed organic pigment or pigment mixture is suspended in the presence of a water-insoluble granulating aid and substantially water are added. A two-phase system consisting of an insoluble, organic solvent in which the granulation aid is at least partially soluble and a substantially second liquid phase is stirred and granulated until granules are formed, then obtained Disclosed is a method of granulating an organic pigment or pigment blend which comprises removing a solvent from the granulate. However, this granulation method is also intended for organic pigments or pigment blends, and even if a powder having an average particle diameter of 0.8 μm or less is granulated by this method, the obtained granules are fragile, It has drawbacks such as easy dust formation.

As a method of granulating an inorganic powder for solving these drawbacks, the present inventors have previously proposed a solution in which an inorganic powder having an average particle diameter of 0.8 μm or less and a granulation aid are dissolved in a solvent or The dispersion obtained by dispersing the granulation aid in a solvent is put into a mixing and stirring type granulator, and granulated while maintaining the inside of the granulator at a temperature lower than the melting temperature of the granulation aid, and the obtained granulation A method has been proposed which consists in drying the product (Japanese Patent Laid-Open No. 3-165827).
Issue).

[0006]

However, the granulation product obtained by the above-mentioned granulation method contains a granulation aid, and the characteristics of the powder itself, which is the raw material, is the granulation aid. However, it is not preferable because the use is limited.

Therefore, an object of the present invention is to prevent dust scattering during handling, that is, to prevent environmental pollution, and to use a hopper of a molding machine when using a powder granulated product in an injection molding machine or an extrusion molding machine. It is an object of the present invention to provide a powder granulated product which can be efficiently used without causing a bridge phenomenon inside or inside a screw part, and which does not contain a granulating aid such as wax, and a manufacturing method thereof.

[0008]

Means for Solving the Problems That is, the powder granulated product according to the present invention is a powder made of a raw material fine powder having a specific surface area of 50 m ² / g or more, a bulk specific gravity of 0.2 or less, and an average particle diameter of 300 mμ or less. It is a granulated product, and is characterized by having a bulk specific gravity of 0.2 to 0.8 g / cm ³ , an average particle size of 50 to 4500 μm, and a rotational strength of 2.0% or less.

Further, in the method for producing the above-mentioned powder granulated product according to the present invention, the specific surface area is 50 m ² / g or more and the bulk specific gravity is 0.2 or less,
A raw material fine powder having an average particle diameter of 300 mμ or less and a volatile granulating aid are charged into a mixing and stirring type granulator to granulate,
It is characterized in that the obtained granulated product is dried.

[0010]

The powder granulated product of the present invention has a specific surface area of 50 m ² /
g or more, bulk specific gravity of 0.2 or less, average particle size of 300 mμ
It is made of the following raw material fine powder. If the specific surface area of the raw material fine powder is 50 m ² / g or more, the resin or the like can be easily filled, and if the bulk specific gravity is 0.2 or less, blocking or the like is less likely to occur, and the average particle size is 300 mμ.
This is because if it is below, filling into a resin or the like becomes easy.

As the raw material fine powder used in the present invention, for example, control of chemical reactivity such as oxidation, reduction and deliquescent,
Surface treatment by conventional methods for controlling taste, odor, toxicity, charging, conductivity, optical characteristics, wettability (hydrophobicity), solubility, surface activity control, fluidity control, etc. It is also possible to use those that have been subjected to.

The raw material fine powder is not particularly limited, and any of organic fine powder and inorganic fine powder can be used. The organic fine powder is not particularly limited, and a wide range can be used. Further, as the inorganic fine powder, for example, carbon, chromium oxide, zinc white, ferrite, titanium dioxide, alumina, magnesium oxide,
Examples thereof include aluminum hydroxide, magnesium hydroxide, mica powder, bentonite, talc, clay, silica, calcium carbonate, magnesium carbonate, sodium bicarbonate and the like.

The powder granulated product of the present invention substantially consists of the above-mentioned raw material fine powder, and the granulation aid used during granulation disappears. That is, at the time of granulation, using a volatile one as a granulation aid, usually wax, plasticizer, metal soap, metal, rubber, resin, which is used at the time of granulation of powder,
It is characterized by not using a water swelling agent, sugar, oil, etc.

The volatile granulating aid used in the production of the powder granulated product of the present invention includes water, alcohol-based aids, hydrocarbon-based aids, ester-based aids, halogenated hydrocarbons. System auxiliaries, nitro hydrocarbon auxiliaries, amine auxiliaries,
Examples thereof include ether auxiliary agents, ketone auxiliary agents, plasticizing auxiliary agents, other auxiliary agents (for example, furfural, aldol, etc.) and a mixture of two or more kinds of these auxiliary agents.

Examples of alcohol-based auxiliaries include methyl alcohol, ethyl alcohol, isopropyl alcohol, amyl alcohol, butyl alcohol and ethylene glycol. Examples of hydrocarbon-based auxiliaries include toluene, xylene, petroleum ether, lacquer diluent, petroleum naphtha, gasoline, isooctane, and hexane. Examples of the ester type auxiliary agents include methyl acetate, ethyl formate, butyl lactate, methyl benzoate, ethylene carbonate and the like. Examples of the halogenated hydrocarbon type auxiliaries include methyl chloride, trichloroethylene, freon and chloronitroethane. Examples of amine-based auxiliaries include methylamine, butylamine, aniline and the like.
Examples of the ether type auxiliary agent include methyl ether, methyl cellosolve, carbitol, methylal, acetal and the like. As the ketone type auxiliary agent, for example, acetone, methyl ethyl ketone, butyron, valerone or the like can be used. Examples of the plasticizer aid include dimethyl phthalate, diisobutyl adipate, castor oil, and chlorinated paraffin.

In producing the powder granulated product of the present invention, the above raw material fine powder and a volatile granulating aid are mixed,
Granulate with a mixing and stirring type granulator. The blending amount of the raw material fine powder and the auxiliary agent is 30 parts by weight per 100 parts by weight of the raw material fine powder.
Approximately 150 parts by weight, but this blending amount can be appropriately selected in order to obtain desired characteristics such as bulk specific gravity, average particle size and rotational strength of the resulting powder granulated product, and is not particularly limited. Not a guideline.

The granulation step can be carried out using a conventional granulator, and for example, it is preferable to use a mixing and stirring type granulator with temperature control. Each condition in the granulation step is not particularly limited and may be appropriately selected in consideration of the raw material fine powder, the volatile granulating aid, the desired characteristics of the obtained granulated product, and the like.

The drying step is also not particularly limited, and the auxiliary agent is used so that the granulating agent having volatility does not remain in the obtained granulated product and is substantially composed of the raw material fine powder. It suffices if it can be removed.

The powder granulated product thus obtained has a bulk specific gravity of 0.2 to 0.8 g / cm ³ and an average particle size of 50 to 45.
It has characteristics of 00 μm and a rotation strength of 2.0% or less.
If the bulk specific gravity is less than 0.2 g / cm ³ , blocking tends to occur, and if it exceeds 0.8 g / cm ³ , dispersibility deteriorates. Also, if the average particle size is less than 20 μm, it may adhere to a packing bag made of vinyl or the like due to static electricity,
A problem such as adhesion to a metal, resin, or resin-coated hopper may occur, and it may cause a disaster due to static electricity or the like, which is not preferable. Also. If the average particle size exceeds 4500 μm, the accuracy of quantitative supply deteriorates, which is not preferable. The powder granulated product of the present invention has a rotational strength of 2.0% or less and does not pulverize into powder even though the granulation aid is absent.

[0020]

【Example】

Example 1 100 parts by weight of a silica fine powder having a specific surface area of 300 m ² / g, a bulk specific gravity of 0.03 g / cm ³ and an average particle diameter of 7 mμ, and 105 parts by weight of methanol as a granulation aid were mixed and agitated with temperature control. Put in granulator, agitator rotation speed 900rpm
And granulated to obtain a granulated product. Next, the obtained granulated product was dried at a maximum temperature of 105 ° C. to obtain a powder granulated product having an average particle size of 1700 μm, a bulk specific gravity of 0.35 g / cm ³ , and a rotational strength of 2.0% or less. No granulation aid was present in this powder granulated product. Further, when the adhesiveness was observed with a metal plate and a resin plate, no adhesion occurred.

Example 2 Specific surface area 160 subjected to hydrophobic treatment with an organic metal oxide
m ² / g, bulk specific gravity 0.05 g / cm ³ , average particle diameter 7 mμ
100 parts by weight of the silica fine powder and 95 parts by weight of a methanol mixed aqueous solution as a granulation aid were put in a mixing and stirring type granulator with temperature control, and granulated at an agitator rotation speed of 1050 rpm to obtain a granulated product. Next, the obtained granulated product was dried at a maximum temperature of 105 ° C. to obtain a powder granulated product having an average particle size of 550 μm, a bulk specific gravity of 0.51 g / cm ³ , and a rotational strength of 2.0% or less. No granulation aid was present in this powder granulated product. Further, when the adhesion was observed in the same manner as in Example 1, no adhesion occurred.

Example 3 Specific surface area 120 subjected to hydrophobic treatment with an organic metal oxide
m ² / g, bulk specific gravity 0.05 g / cm ³ , average particle diameter 16 m
100 parts by weight of silica fine powder of μ and 110 parts by weight of a methanol mixed aqueous solution as a granulation aid were put into a mixing and stirring type granulator with temperature control, and an agitator rotation speed was 1000 rpm.
And granulated to obtain a granulated product. Next, the obtained granulated product was dried at a maximum temperature of 105 ° C. to obtain a powder granulated product having an average particle size of 1500 μm, a bulk specific gravity of 0.38 g / cm ³ , and a rotational strength of 2.0% or less. No granulation aid was present in this powder granulated product. Further, when the adhesiveness was observed in the same manner as in Example 1, there was no adhesion.

Example 4 100 parts by weight of a carbon black fine powder having a specific surface area of 800 m ² / g, a bulk specific gravity of 0.12 g / cm ³ and an average particle diameter of 30 mμ, and 105 parts by weight of toluene as a granulating aid are temperature-controlled. Put in a mixing and stirring type granulator, and rotate agitator at 1
Granulation was performed at 200 rpm to obtain a granulated product. Next, the obtained granulated product is dried at a maximum temperature of 120 ° C. to give an average particle size of 51
A powder granulated product having a particle size of 0 μm, a bulk specific gravity of 0.29 g / cm ³ , and a rotational strength of 2.0% or less was obtained. No granulation aid was present in this powder granulated product. Further, when the adhesiveness was observed in the same manner as in Example 1, there was no adhesion.

Example 5 Specific surface area of 1300 m ² / g, bulk specific gravity of 0.07 g / cm ³ ,
100 parts by weight of carbon black fine powder having an average particle size of 16 mμ, and a methanol mixed aqueous solution 125 as a granulation aid
Part by weight was placed in a mixing and stirring type granulator with temperature control, and granulated at an agitator rotation speed of 1500 rpm to obtain a granulated product.
Next, the obtained granulated product was dried at a maximum temperature of 120 ° C. to obtain a powder granulated product having an average particle size of 310 μm, a bulk specific gravity of 0.23 g / cm ³ , and a rotational strength of 2.0% or less. No granulation aid was present in this powder granulated product. Further, when the adhesiveness was observed in the same manner as in Example 1, there was no adhesion.

Reference Example 1 90 parts by weight of low density polyethylene (LDPE) as a resin,
Five kinds of mixtures obtained by using 10 parts by weight each of the silica fine powder and the carbon black fine powder used as raw material fine powders in Examples 1 to 5 as additives were molded using a screw extruder with heating control. When extrusion molding was performed at a temperature of 165 ° C., blocking was observed and molding was impossible.

Reference Example 2 The powder granulated products obtained in Examples 1 to 5 were used and extrusion-molded by the same method as in Reference Example 1 with the compounding ratios shown in Table 1 below. The results shown in Table 1 were obtained. was gotten.

[0027]

[Table 1]

[0028]

EFFECTS OF THE INVENTION The powder granulated product of the present invention has the following characteristics: No additives such as wax and the like does not change the physical properties of the raw material fine powder; used as additives for resins, etc. In this case, high filling is possible; dust scattering of powder can be prevented; compression molding can be performed; handleability is good; blocking can be prevented.

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[Procedure amendment]

[Submission date] December 14, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

[0010]

The powder granulated product of the present invention has a specific surface area of 50 m ² /
g or more, bulk specific gravity of 0.2 or less, average particle diameter of 300 mμ
It is made of the following raw material fine powder. The specific gravity of the powder raw material fines becomes easy filling of the resin is less than 50 m 2 ^/ g, bulk density is less likely to occur when Ru exceeds 0.2 such as blocking, addition, average particle diameter exceeds 300mμ Granulation according to the present invention because it is easy to fill the resin and the like.
No special treatment is required .

Claims (2)

[Claims] 1. A specific surface area of 50 m ² / g or more and a bulk specific gravity of 0.2.
Hereafter, it is a powder granulated product composed of raw material fine powder having an average particle diameter of 300 mμ or less, and a bulk specific gravity of 0.2 to 0.8 g / cm ³ ,
Average particle size is 50-4500 μm and rotation strength is 2.0%
A powder granulated product characterized by the following: 2. The method for producing a powder granulated product according to claim 1, wherein the specific surface area is 50 m ² / g or more and the bulk specific gravity is 0.2 or less,
A raw material fine powder having an average particle diameter of 300 mμ or less and a volatile granulating aid are charged into a mixing and stirring type granulator to granulate,
A method for producing a powder granulated product, which comprises drying the obtained granulated product.