JP2008115211A - Method for producing core body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an extrusion molded core body for forming a thick coating film containing a fine particle in a high concentration by writing. <P>SOLUTION: The method for producing the core body comprises previously attaching a part or the whole of the fine particle having an average particle diameter of ≤100 nm to the surface of a platy extender material to give a fine particle attached platy extender material, mixing the fine particle attached platy extender material with a core body material, kneading the mixture and then extrusion molding the kneaded product. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a molded body containing fine particles of 100 nm or less, and further relates to a method for producing a core capable of forming a coating film containing fine particles at a high concentration.

Fine particles of 100 nm or less are materials that have been actively researched in recent years, and have characteristics such as the development of transistors and light-emitting diodes and other electronic component materials that make use of superconducting properties, and the capture and support of catalysts and bacteria. Various researches have been made utilizing the properties of carbon and the structural features of fine particles, such as the development of biopharmaceuticals.
A film containing fine particles having various physical properties at a high concentration is expected as a functional film for various applications. For example, functional coatings such as conductor coatings, semiconductor coatings, photocatalytic coatings, adsorption coatings, lubricating coatings, polishing coatings, thin film electrodes, and gas separation membranes are particularly expected.
As a material capable of forming a coating film containing fine particles of 100 nm or less by writing, a core formed by press molding using a binding material such as a small amount of wax or a pencil core obtained by adding a small amount of fullerene as fine particles to Patent Document 1. Is disclosed.
JP-A-8-73797

As a writable core, Patent Document 1 describes a pencil core containing fine particle fullerene. However, since the content is about 0.5% by weight, the characteristics of the fine particles could not be exhibited. In order to exhibit the properties effectively, it is necessary to contain fine particles at a high concentration in the molded product, but if the fine particles in the molded product are contained at a high concentration, the strength will decrease and it will break immediately when writing. There was a problem that I could not write. There has been a demand for a method for producing a molded body having a strength to form a thick film by writing while containing fine particles at a high concentration.
It is an object of the present invention to provide a method for producing an extruded core that can form a thick film containing fine particles at a high concentration by writing.

  Part or all of fine particles having an average particle diameter of 100 nm or less are adhered to the surface of the plate-like material in advance to be mixed with the core material, kneaded, and then manufactured by extrusion. The method is summarized.

When the particle size is 100 nm or less, the surface area becomes very large and the activity becomes high. For this reason, there is a characteristic that the aggregate becomes a large aggregate. When the fine particles were contained at a high concentration and molded into a core body, the aggregation was large and non-uniform agglomerates were dispersed, which was also a cause of weak strength.
A part or all of fine particles having an average particle size of 100 nm or less can be adhered to the surface of the plate-like material in advance to form a fine particle-attached plate-like material, thereby preventing aggregation, and the plate-like material can be concentrated at a high concentration. Since it adheres, it became possible to make a highly concentrated impregnated core. Further, by using a plate-like material, wear during writing is promoted, so that it can be smoothly applied together with the nanoparticles and a thick film can be formed.
Moreover, since the fine particle-adhered plate-like material is oriented in the molding direction by extrusion molding, the density of the core body is increased, and the strength sufficient for writing can be obtained.

Examples of fine particles of 100 nm or less include fine metal particles such as Ni particles, Co particles and Fe particles, fine particles such as magnetic polyethyleneimine, fullerenes, carbon nanotubes and carbon nanohorns, multilayer carbon fine particles, carbon fine particles such as nano-onion particles, oxidation Examples thereof include fine metal oxides such as titanium, zirconia oxide, aluminum oxide, and silica, and metal colloids. As commercial products, fullerene is Nanomu Black, Nanomu mix (above, manufactured by Frontier Carbon Co., Ltd.), carbon nanotube is Carval (above, produced by GCI Creos Co., Ltd.), VGCF-S (above, produced by Showa Denko Co., Ltd.), photocatalyst. Titanium oxide is AMT-100, AMT-600 (above, manufactured by Teika Co., Ltd.), silica particles are sicasar (above, COREFRONT Co., Ltd.), magnetic polyethyleneimine particles are MIP (above, COREFRONT Co., Ltd.), magnetic dextran. Examples thereof include particles nanomag-Dspio (hereinafter referred to as COREFRONT Co., Ltd.).
The content of these fine particles may be 10% by weight or more and 70% by weight or less with respect to the weight of the core remaining as a solid excluding volatile components. If the amount is less than 10% by weight, the amount of fine particles cannot be exhibited because the amount of adhesion to the surface of the plate-like material particles decreases. If the content exceeds 70% by weight, the aggregates of excess fine particles from the surface of the plate-like material particles are dispersed non-uniformly, so that the strength of the core is reduced and the core is easily broken. End up.
In addition, when the particle size of the fine particles becomes 100 nm or more, the reason is not clear, but the strength rapidly decreases.

  Examples of the plate-like material include silicon nitride, alumina, sericite, talc, mica, graphite, kaolin clay, bentonite, Nε-lauroyllysine, boron nitride, mica, N-lauroyl-β-alanine calcium, calcium carbonate, One or two or more mixtures and / or composites selected from magnesium carbonate and magnesium sulfate can be used. Further, potassium titanate whisker, calcium carbonate whisker, titanium dioxide whisker, magnesium sulfate whisker, calcium sulfate whisker, aluminum sulfate whisker or the like may be optionally added as a fibrous material as long as the effect of the present invention is not impaired. .

  A conventionally known method can be used as a method for obtaining a plate-like material with a fine particle attached of 100 nm or less. For example, the plate-like material is first agitated with a disperser such as a Hensyl mixer in advance, and the particles are gradually added while controlling the rotation speed so that the plate-like material particles are not crushed. Dry treatment such as attaching fine particles to the surface, and further dispersing the fine particles in a volatile organic solvent, putting the plate-like material into it, and heating and evaporating the solvent, gradually attaching the fine particles to the surface of the plate-like material Wet treatment to be carried out, and further, the plate-like material particles are put in a vessel in which the particles are stirred in a gas phase, and the dispersion in which the fine particles are dispersed with a volatile organic solvent is sprayed to adhere to the surface of the plate-like material particles A semi-wet method can be mentioned. In short, the composite particles in which at least fine particles are covered and adhered to the surface of the plate-like material particles can be obtained without destroying and refining the plate-like material particles, such as wet or dry processing. In other words, no means is chosen. These fine particle-adhered plate-like materials may be used in combination with an untreated plate-like material that does not adhere with fine particles.

  Examples of binders for shaping the above materials include cellulose derivatives such as nitrocellulose, ethyl cellulose, methyl cellulose, cellulose acetate, carboxymethyl cellulose, hydroxyethyl cellulose, polystyrene, polyethylene, polypropylene, polybutene, polybutadiene, polymethylpentene, Polystyrene butadiene, polyvinyl chloride, polyvinyl acetate, polymethyl acrylate, polymethyl methacrylate, polyvinylidene chloride, polytetrafluoroethylene, acrylic-styrene resin, acrylonitrile butadiene styrene resin, ethylene-tetrafluoroethylene copolymer, polyethylene glycol , Polypropylene glycol, polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyvinyl chloride Pyrrolidone, polyvinyl ether, maleic acid polymers, polyester polyol resins, polyester polyether resins, polyethylene terephthalate, and synthetic resins such as polybutylene terephthalate. These may be used alone or in combination of two or more.

  In addition, if the range does not hinder the effects of the present invention, natural wax groups such as carnauba wax, beeswax, and wax, synthetic systems such as polyethylene wax, montan wax, paraffin wax, distearyl ketone, and microcrystalline wax It may be used in combination with a wax group, various metal salts of stearic acid such as stearic acid, aluminum stearate, magnesium stearate and calcium stearate, and various lubricity promoting materials such as various fatty acid amides.

  In the present invention, the above-mentioned compounding materials are arbitrarily blended, and a polar solvent such as water, MEK, alcohol and acetone, and a nonpolar solvent such as toluene are used as necessary, while a hensil mixer, a ball mill, a three roll mill The mixture is molded after kneading by agitation, pulverization, or a dispersing machine. There are a method in which mold-molding and extrusion molding are performed while heating and melting, followed by cooling, and a method in which a kneaded product is separately placed in a cylinder and extruded by a hydraulic piston. The extrusion conditions at that time are arbitrary, but as an example, the extrusion temperature may be about 30 ° C. to 50 ° C., and the extrusion pressure may be molded in the range of 1.96 MPa to 9.81 MPa. Further, water and organic solvent remaining after molding may be forcibly dried using a dryer.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded.

<Example 1>
<Preparation of carbon particulate adhering plate-like material A>
Fullerene (carbon fine particles, nanomix, 1 nm, manufactured by Frontier Carbon Co., Ltd.)
40 parts by weight methylcyclohexane (organic solvent) 100 parts by weight talc (plate material) 40 parts by weight Make a dispersion containing the fullerene in methylcyclohexane and stir the talc with a 3 liter Hensyl mixer at a low speed of 500 rpm. Stirring was continued while gradually dropping the fullerene dispersion while being dispersed, followed by drying to obtain a carbon fine particle-attached plate-like material A having fullerene particles attached to the talc surface.

Carbon particulate adhering plate-like material A 80 parts by weight nitrocellulose (binding material) 14 parts by weight aluminum stearate (lubrication promoting material) 3 parts by weight carnauba wax (lubrication promoting material) 2 parts by weight propylene carbonate (plasticizer) 1 part by weight 100 parts by weight of methyl ethyl ketone (organic solvent) After blending the above materials, kneading with a kneader or hensil mixer, kneading with a three roll and further dispersing, molding using a vertical extruder, the core obtained is And dried at 80 ° C. for 8 hours to obtain a rod-shaped core body having a diameter of 2 mm and containing fullerene. Fullerene fine particle content 40% by weight.

<Example 2>
<Preparation of particulate metal oxide-attached plate-like material B>
Fine particle titanium oxide (AMT-100, average particle size: 6 nm, manufactured by Teika Co., Ltd.)
70 parts by weight methylcyclohexane (organic solvent) 100 parts by weight talc (plate-like material) 10 parts by weight A dispersion containing the fine particle titanium oxide in methylcyclohexane was prepared, and talc was slowed down at a speed of 500 rpm with a 3-liter Hensyl mixer. While continuing to stir while the dispersion of fine particle titanium oxide is gradually dropped while being dispersed by stirring, the plate-like material B with fine particle metal oxide adhered to the surface of the talc is dried and fine particle titanium oxide particles are adhered. Obtained.

Particulate metal oxide adhering material B 80 parts by weight nitrocellulose (binding material) 14 parts by weight aluminum stearate (lubrication promoting material) 3 parts by weight carnauba wax (lubrication promoting material) 2 parts by weight propylene carbonate (plasticizer) 1 100 parts by weight Methyl ethyl ketone (organic solvent) 100 parts by weight The above materials were blended, kneaded with a kneader or hensil mixer, then kneaded with three rolls and further dispersed, and molded using a vertical extruder, and then the core obtained The body was dried at 80 ° C. for 8 hours to obtain a rod-shaped core body having a diameter of 2 mm containing a fine particle metal oxide. Titanium oxide fine particle content 70 wt%

<Example 3>
<Preparation of silica particulate adhering plate-like material C>
Silica fine particles (sicastar 43-00-102, average particle size 100 nm, COREFLON Corporation)
10 parts by weight methylcyclohexane (organic solvent) 100 parts by weight talc (plate-like material) 70 parts by weight A dispersion containing the silica fine particles in methylcyclohexane was prepared, and talc was added at 500 rpm with a 3 liter Hensyl mixer. While being dispersed by low-speed stirring, stirring was continued while gradually adding a dispersion of silica fine particles, and then drying was performed to obtain a silica fine particle-attached plate-like material C having silica fine particles attached to the talc surface.

Silica fine particle adhering plate-like material C 80 parts by weight nitrocellulose (binding material) 14 parts by weight aluminum stearate (lubrication promoting material) 3 parts by weight carnauba wax (lubrication promoting material) 2 parts by weight propylene carbonate (plasticizer) 1 part by weight 100 parts by weight of methyl ethyl ketone (organic solvent) After blending the above materials, kneading with a kneader or hensil mixer, kneading with a three roll and further dispersing, molding using a vertical extruder, the core obtained is And dried at 80 ° C. for 8 hours to obtain a rod-shaped core body having a diameter of 2 mm containing silica fine particles. Silica fine particle content 10% by weight

<Comparative Example 1>
<When there is no adhesion process to the plate-like material>
Fullerene (previously described) 40 parts by weight nitrocellulose (binding material) 14 parts by weight aluminum stearate (lubrication promoting material) 3 parts by weight carnauba wax (lubrication promoting material) 2 parts by weight talc (plate-like material) 40 parts by weight propylene carbonate ( Plasticizer) 1 part by weight methyl ethyl ketone (organic solvent) 100 parts by weight The above materials were blended, kneaded with a kneader or hensil mixer, kneaded with a three-roller and further dispersed, after molding using a vertical extruder, The obtained core was dried at 80 ° C. for 8 hours to obtain a rod-shaped core having a diameter of 2 mm and containing fullerene. Fullerene fine particle content 40 wt%

<Comparative example 2>
<Preparation of silica-attached plate-like material D>
Silica (sicastar 43-00-202, average particle size 200 nm, manufactured by COREFRONT)
50 parts by weight methylcyclohexane (organic solvent) 100 parts by weight talc (plate-like material) 30 parts by weight A dispersion containing the silica in methylcyclohexane was prepared, and the talc was stirred at a low speed of 500 rpm with a 3 liter Hensyl mixer. Stirring was continued while gradually adding a silica dispersion while being dispersed, followed by drying to obtain a silica-attached plate-like material D having silica particles attached to the talc surface.

Silica-attached plate-like material D 80 parts by weight Nitrocellulose (binding material) 14 parts by weight Aluminum stearate (lubrication promoting material) 3 parts by weight Carnauba wax (lubrication promoting material) 2 parts by weight Talc (plate-like body material) 30 parts by weight Propylene carbonate (plasticizer) 1 part by weight Methyl ethyl ketone (organic solvent) 100 parts by weight The above materials are blended, kneaded with a kneader or hensil mixer, then kneaded with three rolls and further dispersed, using a vertical extruder. After molding, the obtained core was dried at 80 ° C. for 8 hours to obtain a rod-shaped core having a diameter of 2 mm containing silica. Silica fine particle content 50% by weight

<Comparative Example 3>
<Preparation of silica-attached plate-like material E>
Silica (previously described) 75 parts by weight methylcyclohexane (organic solvent) 100 parts by weight talc (plate material) 5 parts by weight A dispersion containing the silica in methylcyclohexane is prepared, and talc is added to a 3 liter Hensyl Missixer at 500 rpm. While being dispersed by low-speed stirring, stirring was continued while gradually adding a dispersion of silica particles to obtain a silica-attached plate-like material E having silica particles attached to the talc surface.

Silica particle-attached plate-like material 80 parts by weight nitrocellulose (binding material) 14 parts by weight aluminum stearate (lubrication promoting material) 3 parts by weight carnauba wax (lubrication promoting material) 2 parts by weight propylene carbonate (plasticizer) 1 part by weight methyl ethyl ketone (Organic solvent) 100 parts by weight The above materials were blended, kneaded with a kneader or hensil mixer, then kneaded with a three roll and further dispersed, and after molding using a vertical extruder, the resulting core was It dried at 80 degreeC for 8 hours, and obtained the rod-shaped core body of diameter 2mm containing a silica particle. Silica particle content 75 wt%

<Comparative Example 4>
<Preparation of silica-attached plate-like material F>
Silica (previously described) 5 parts by weight methylcyclohexane (organic solvent) 100 parts by weight talc (plate-like material) 75 parts by weight A dispersion containing the silica in methylcyclohexane is prepared, and talc is added to a 3 liter Hensyl Missixer at 500 rpm. While being dispersed by low-speed stirring, stirring was continued while gradually adding a dispersion of silica particles to obtain a silica-attached plate-like material F having silica particles attached to the talc surface.

Silica particle-attached plate-like material 80 parts by weight nitrocellulose (binding material) 14 parts by weight aluminum stearate (lubrication promoting material) 3 parts by weight carnauba wax (lubrication promoting material) 2 parts by weight propylene carbonate (plasticizer) 1 part by weight methyl ethyl ketone (Organic solvent) 100 parts by weight The above materials were blended, kneaded with a kneader or hensil mixer, then kneaded with a three roll and further dispersed, and after molding using a vertical extruder, the resulting core was It dried at 80 degreeC for 8 hours, and obtained the rod-shaped core body of diameter 2mm containing a silica particle. Silica particle content 5% by weight

The bending strength (unit: MPa) of the rod-shaped core containing fine particles obtained in each of the above examples was measured based on JIS S 6005.
Further, each fine particle-containing core is rubbed 20 times in front, back, left, and right with a writing angle of 60 degrees and a load of 400 g on the surface of a research-use magnetic heat-resistant plate (arithmetic average roughness (Ra): about 5 μm), Formed.
In order to evaluate the film thickness on the surface of the fine particle film, the thickness of the film was measured with a confocal laser scanning microscope (LSM5 PASCAL MAT, manufactured by ZEISS Co., Ltd.). Sa value (arithmetic mean height of contour plane, unit: μm) Asked. In addition, it means that a coating film is thick, so that Sa value is large.

Claims (2)

A core body in which a part or all of fine particles having an average particle diameter of 100 nm or less are previously adhered to the surface of the plate-like material, mixed with the core material, kneaded, and then molded by extrusion. Manufacturing method. The core production method according to claim 1, wherein the content of the fine particles is 10% by weight or more and 70% by weight or less.