JPS58198581A - Abrasive composition and its preparation - Google Patents

Abstract

PURPOSE:To provide an abrasive compsn. which does not cause surface defects even on thin and brittle substrates, prepared by dispersing in organic solvent an inorganic compd. powder having the surface covered with a silicone resin film. CONSTITUTION:Inorganic compd. powder [e.g. SiO2, Al2O3, Cr2O3, MgO, ZnO, CaO, Al(OH)3, CaTiO3, CaSO4, PbSO4 or diatomaceous earth] is dispersed in an organic solvent (e.g. methanol). For example, the surface of powdered inorganic compd. is coated with a silicon oil (e.g. methylhydrogensiloxane) and it is subjected to heat treatment to coat the powder with siloxane powder (silicon resin). To obtain the abrasive compsn. in slurry, the coated powder is dispersed in organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polishing composition for polishing a mirror-like surface of metal, glass, etc., and a method for producing the same.

Generally, the polishing composition used to polish mirror polishing materials such as metals and glass is a metal oxide.

Sulfates, carbonates, titanates, silicates, silica.

The mainstream is a slurry made by dispersing silica gel, diatomaceous earth, etc. in water or an organic solvent.

In addition, several abrasives have been proposed in which various polymers are mixed with the above-mentioned inorganic compounds in order to improve dispersibility and releasability.

On the other hand, mirror-finished materials, which are objects to be polished, are used for various purposes, but all of them have hard surfaces.

The general abrasives used for this purpose, such as those mentioned above, are also quite hard. However, some mirror materials are very brittle and thin, and if a conventional abrasive such as the one described above is used to polish them, islands, holes, and peeling occur on the surface, which is undesirable.

For example, in a selenium drum used as a photoreceptor in a copying machine, an amorphous selenium layer with a thickness of about 10 μm is formed on a cylindrical surface of copper or aluminum. It is difficult to polish the surface of such H-layer selenium, and if ordinary abrasives are used, there is a high risk of damaging the surface to be polished.

This invention aims to provide a polishing composition that does not cause surface defects even for M-layer and highly brittle materials.
target

This invention covers the powder with a film of an inorganic compound powder (silicone resin) by coating the surface of the inorganic compound powder with, for example, silicone oil and then heat-treating the powder.
This is dispersed in an organic solvent to obtain a polishing composition, which is used in the form of a so-called slurry.

The inorganic compound powder used here has a particle size of 50 l.
It is desirable that the material is less than tm, and its material is SiO.
2, A12o3. Cr2039Mqo, ceO2, Zn
o.

CaO, ZrO2, AI (OH)3. CaTiO3,
SrTiO3゜Ca S iOa lCa S 04
s S r S O4t B a S O4-P b
S O4tCa COa, diatomaceous earth, and activated clay are used. In addition to these, commonly used abrasives can also be used.

As the silicone oil, an alkylhydrogen siloxane containing hydrogen is suitable. This is because the reaction mechanism during the heat treatment process of silicone-on-oil is as shown in the following chemical structural formulas I and II. Formula I is an alkylhydrodiene siloxane before being heat treated;
Formula (2) shows an alkylhydrodiene siloxane in which an oxidative dehydration reaction occurs after heat treatment, resulting in new crosslinking of siloxane bonds.

In the following formula I, the hydrogen atoms shown in black boxes in the siloxane are oxidized by oxygen in the air, and a dehydration reaction occurs here, resulting in new crosslinking of siloxane bonds, as shown in 2). This reaction occurs one after another between adjacent hydrogen atoms and develops into a three-dimensional network structure, forming a silicone resin.1 When using alkylnohydrodieneroxane in this way, it is easy to use with only a dehydration reaction that involves heat treatment. can be coated with silicone resin. Here, a methyl group or a phenyl group is generally used as the alkyl group bonded to silicone. That is, as the silicone oil, methylhydrogensiloxane or phenylhydrodienesiloxane is preferable.

The abrasive powder thus obtained is dispersed in an organic solvent, and alcohols such as methanol, ethanol, isopropanol, etc. are inexpensive and have good dispersibility and are optimal.

Examples of the present invention are shown below.

Dilute 0.6y- of silicone oil to 10% solvent resistance.

The solvent used here is a chlorinated hydrocarbon such as trichlene or perchrene. Silicone oil is soluble in other hydrocarbon solvents, but since it will be heat treated later, it is safe to use nonflammable trichlene and percrene.

Among the inorganic compound powders listed above, S*02 (7 Lika) is used here. 4 o of silica powder
The mixture is placed in a beaker, stirred, and then a diluted solution prepared by diluting the silicone oil with the solvent is added to uniformly adhere to the surface of the silica powder. The solvent is removed from this in a rotary kiln, followed by heat-smoking treatment for 16 days.
OC for 1 hour to polymerize the silicone oil and form a film of silicone resin (1") on the surface of the silica powder.

This abrasive powder was mixed with ethanol 1oOR as an organic solvent.
Let A be the abrasive dispersed in T. On the other hand, as a target abrasive for comparison, an abrasive B is prepared by dispersing silica powder 401P in ethanol 100-. Absorbent cotton was soaked in each abrasive and a selenium drum of a copying machine was polished, and a comparative test was conducted by visual observation. As a result, when abrasive B was used, several gaps were observed, whereas when abrasive A was used, there were no surface defects such as islands, and the toner, its sacrum, etc. I was able to remove the kimono cleanly.

As can be seen from the above examples, according to the present invention, by coating the surface of the mineralized inclusion powder with silicone resin, it is possible to polish a thin layer that does not cause surface defects even on highly brittle materials. A composition is obtained. In addition, since silicone resin has water repellency and releasability, it is difficult for the abrasive to adhere to the surface to be polished, and even if it does, it can be easily wiped off with a gentle wipe afterwards. .

Name of agent: patent attorney Toshio Nakao and one other person.

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Claims (1)

[Scope of Claims] (1) A polishing composition comprising an inorganic compound powder having a silicone resin coating formed on its surface dispersed in an organic solvent. 0) Inorganic compound powder is SiO2, Al2O3, Cr2O
3゜MqO, CeO2, ZnO, CaO, ZrO2, A
I(OH)3tCaTiO3,5rTi03. CaSi
O3, CaSO4, SrSO4゜Ba5o4. Pb5o
4. CaCo3. The polishing composition according to claim 1, which is selected from the group consisting of diatomaceous earth and activated clay. (3) For polishing, which is characterized by attaching silicone oil to the surface of an inorganic compound powder, heat-treating it to form a silicone resin film, and dispersing the inorganic compound powder with the silicone resin film formed in an organic solvent. Method for manufacturing the composition. ←) The method for producing a polishing composition according to claim 3, wherein the silicone oil is an alkyl hydrogen siloxane. ←) The method for producing a polishing composition according to claim 3, wherein the silicone oil is diluted with triclene or noku-klene.