JPH01177966A - Barrel finishing method for inorganic hard body - Google Patents

Abstract

PURPOSE:To make it possible to simply and largely manufacture an inorganic hard body having a fine lustrous surface by using a barrel-finishing medium consisting of flexible synthetic resin and inorganic polishing material. CONSTITUTION:A solid product consisting of flexible synthetic resin and inorganic polishing material is used as a barrel-finishing medium, and added into liquid such as water or the like, and then used for the barrel finishing of glass, ceramics and an inorganic hard body such as a crystal. Thus the inorganic hard body having excellent weight accuracy and a fine lustrous surface with no struck or scratched flaw can be inexpensively end largely manufactured.

Description

[Detailed description of the invention] “Industrial application field” The present invention relates to a barrel polishing method for inorganic hard bodies.

"Prior art" As a method of polishing inorganic hard bodies such as glass, ceramics, crystals, etc., a surface grinding plate with holes or holes is placed parallel to another flat plate, and a grinding plate of a predetermined shape is formed in the holes or holes. There is a cold working method in which a ladle is placed and the grinding plate is rotated in a predetermined direction while supplying a predetermined abrasive together with a solution such as water to polish the object to be polished. There is also a chemical polishing method in which a polished object processed to a predetermined surface smoothness by the cold working method described above is treated with a chemical such as a hydrofluoric acid solution to obtain a glossy mirror surface. In addition, as disclosed in Japanese Patent Application Laid-Open No. 61-1510289, a regular hexahedral glass plate material is cut, and the regular hexahedral glass is placed in a container.
There is also a method of manufacturing glass spheres having a glossy surface by rotating the container for a predetermined period of time while heating the container to a temperature higher than its softening temperature.

[Problems to be Solved by the Invention] The above-mentioned cold working method has the disadvantage that the number of objects that can be polished at one time is limited and the processing cost is high due to the large number of polishing steps. . In addition, in the chemical polishing method using chemicals mentioned above, the components that make up the rod of the polished object may be selectively eluted from the surface, causing a so-called burnt layer on the surface. It is extremely inconvenient for the body. Furthermore, according to the method disclosed in Japanese Patent Application Laid-Open No. 61-151028, in order to obtain high weight accuracy when manufacturing glass bulbs, a glass material is cut into regular hexahedrons with high precision, and this regular hexahedral glass is The glass must be softened in an active gas atmosphere, which is a very complicated manufacturing process, and the process involves heating the glass above the softening temperature, so when the glasses come into contact, they may fuse together. There is a large possibility that this will occur, making it difficult to manufacture high-quality glass polishing balls at low processing costs.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a method capable of polishing a large amount of inorganic hard bodies such as glass, ceramics, crystals, etc. with high polishing accuracy and at low cost. There is a particular thing.

[Means for solving the problem] The object to be polished is placed in a barrel tank containing barrel media (also called polishing stone), water, surfactant, etc., and the object to be polished is polished by rotating the barrel tank. The barrel polishing method itself has been known for a long time, but since the conventional barrel polishing method uses alumina balls, steel balls, sintered balls mainly composed of silica, etc. as barrel media, The barrel polishing method can only be applied when the object is metal or precious stones with relatively high hardness; barrel polishing is applied to polish inorganic hard materials such as glass, ceramics, and crystals, which have a lower hardness than the metals and precious stones mentioned above. There is no example in the past.

By using an integrated molded product of a flexible synthetic resin and an inorganic abrasive material as the barrel media, the present invention enables polishing of inorganic materials such as glass, ceramics, and crystals, which was impossible with conventional barrel polishing methods. For the first time, barrel polishing of hard materials became possible.

Therefore, the present invention is a barrel polishing method for an inorganic hard body, which is characterized by barrel polishing the inorganic hard body in the presence of an integrated molded product of a flexible synthetic resin and an inorganic abrasive material and water.

The present invention will be explained in detail below.

Examples of the inorganic hard body to be polished in the barrel polishing force method of the present invention include inorganic hard bodies such as glass, ceramics, and crystals. The inorganic hard body preferably used has a hardness within a predetermined range, and in the examples below, the abrasion reaction (F = "A) value shown in the measurement method is 50 to 1000, especially 50 to 200. Among the above-mentioned glasses, ceramics, and crystals, glasses with relatively low hardness are most suitable for barrel polishing by the method of the present invention.

These inorganic hard bodies may have various shapes such as spheres, spherical bodies, ellipsoids, and amorphous bodies having no edges.

In the method of the present invention, the media used for barrel polishing the inorganic hard body is an integrally molded product of a flexible synthetic resin and an inorganic abrasive material.

Here, the integrated molded product of visible synthetic resin and inorganic abrasive material means a molded product in which a flexible synthetic resin is used as a matrix and an inorganic abrasive material is integrally bonded to this. Such an integrally fixed molded article is manufactured, for example, by the methods (a) and (b) in the following.

(b) After adding an inorganic abrasive to a solution obtained by adding a flexible synthetic resin to a solvent that dissolves this synthetic resin and dispersing it, the solvent is evaporated and solidified to obtain the desired shape and size. A molded article in which an inorganic abrasive material is integrally bonded to a flexible synthetic resin matrix is obtained.

Note that a synthetic resin solution containing an inorganic abrasive dispersed therein may be dried by a method such as spray drying to directly obtain an integral molded product. Further, if the bond between the synthetic resin and the inorganic abrasive is weak, a binder may be added to improve the bond.

(b) Adding an inorganic abrasive to a liquid monomer (single substance) or liquid prepolymer (prepolymer) for producing flexible synthetic resin, polymerizing it, and then pulverizing the obtained solid material. As a result, a molded article in which the inorganic abrasive material is integrally bonded to the flexible synthetic resin matrix is obtained. In the above polymerization operation, it is convenient to pass the polymerized product through a sieve with a predetermined mesh before completing the polymerization, and then to complete the polymerization, which saves the trouble of the above-mentioned pulverization. It is.

Examples of flexible synthetic resins used in the present invention include urethane resins, silicone resins, polyamide resins, fluororesins, etc., but as long as they are flexible and support an inorganic abrasive material, , synthetic resins other than those mentioned above can also be used.

Among the above resins, urethane resin is most preferable from the viewpoint of flexibility, cushioning properties, etc., and an integral molded product of this urethane resin and an inorganic abrasive material is preferably produced by the method (b) above. preferable. i.e. liquid monomers (polyisocyanates and polyols) or liquid prepolymers (prepolymers of polyisocyanates and polyols)
After dispersing an inorganic abrasive material in a polymer, it is polymerized, and the polymer that has not completely solidified before completion of polymerization is passed through a predetermined mesh sieve, and then the polymerization is completed to have a predetermined shape and size. An integrated molded product of urethane resin and inorganic abrasive material is obtained.

In addition, when manufacturing an integrated molded product of silicone resin, polyamide resin, fluororesin, etc. and inorganic abrasive material, the above methods (a) or (b) or other methods may be used depending on the properties of these resins. is selected as appropriate.

Inorganic abrasives that are integrally bonded and supported on the 1iJ' JA synthetic resin include inorganic abrasives such as alumina, silica, silicon carbide, green carbon, cerium oxide, zirconium oxide, iron oxide, and chromium oxide. Examples include abrasives.

According to the study of the present inventor, when barrel polishing a hard-purchased body such as glass, ceramics, crystal, etc., it is desirable to perform the barrel polishing by three steps: a barrel process, a middle barrel process, and a finishing barrel process. The barrel polishing method is
Of the above three steps, it is preferable to carry out the latter two steps (middle barrel step and finishing barrel step). From this point of view, as an inorganic abrasive material supported on a flexible synthetic resin, It is preferable to use alumina, cerium oxide, zirconium oxide, etc., which have a relatively fine particle size.

The proportion of inorganic abrasive in the integral molded product varies depending on the abrasiveness required for the integral molded product, the type of flexible synthetic resin, etc.; It is preferable that it is -30 to 6.

The reason for this is that when the inorganic abrasive content is less than 5%, there is too little inorganic abrasive material, making it difficult to grind and polish the object being polished, and when it exceeds 30%, it becomes difficult to grind and polish the object. is incomplete, and there is an inorganic abrasive that does not bond to the synthetic resin.
Further, barrel polishing causes severe wear and lacks durability.

In addition, the size of the integrated molded product of flexible synthetic resin and inorganic abrasive material is appropriately determined depending on factors such as the size of the inorganic hard material to be polished, but the volume ratio should not exceed 2 times. It is preferable to have one. The reason for this is that when the size of the polished object is more than twice the size of the polished object, collisions occur between the polished objects and it becomes difficult to obtain a mirror finish.6 In the barrel polishing method of the present invention, the flexible synthetic An integrated molded product of resin and inorganic abrasive material is used by adding it to water. Water provides fluidity by uniformly dispersing the fixed molded product, and especially when polishing glass, the polishing speed also depends on the chemical durability of the glass1. Much of this is due to the side effect of scraping off the generated soft layer, and it works to further improve the polishing rate. Regarding the amount of water added, the amount of water to be added is 0.00% relative to the level (mass surface) of the integrated molded product when placed in a container with a cross-sectional area of - in the height direction.
The power applied to the height level of 5 to 1.5 times is impressive.

If the amount of water added is lower than 0.5 times the height level, the fluidity of the integrated molded product will deteriorate or the frictional force with the object to be polished will increase, resulting in a decrease in the grinding force or dents on the surface of the object to be polished. This will cause scratch marks, and if the water addition i is made higher than the 1.5 times height level, the viscosity of the slurry consisting of the integrated molded product and water will decrease.
This is because the grinding force of the integrally fixed molded product decreases and collisions between the two products occur.

A surfactant can also be added to the water, and even when water and a surfactant are used, the total amount of water and surfactant added is 0 to the level (mass surface) of the integrated molded product. .5
It is preferable to set the height level to ~1.5 times. Further, it is preferable to add the surfactant in an amount of about 1 to 10% by weight based on water.

According to the study of the name of the present invention, the barrel polishing process can be performed by changing the grain size of the barrel media to perform a coarse barrel process, a medium barrel process,
Although it has become clear that it is preferable to carry out the process in multiple steps such as a finishing barrel process, the barrel polishing method of the present invention involves polishing an integral molded product in which an inorganic abrasive is bonded to a flexible synthetic resin. Since it is used as a media, it is not suitable for use in the rough barrel process, but is suitable for use in any process after the rough barrel process, such as the middle barrel process and the finishing barrel process, especially the finishing barrel process.

As described above, according to the present invention, a flexible synthetic resin that is flexible and has a cushioning function is obtained by integrally bonding an inorganic abrasive material that has abrasive properties. By using an integrated molded product that has the advantages of inorganic abrasive materials as barrel media, barrel polishing of inorganic hard materials such as glass, ceramics, and crystals, which was impossible with conventional barrel polishing methods, is possible. This makes it possible to obtain large quantities of inorganic hard bodies with high weight accuracy and a glossy surface without dents or scratch marks at low cost.

[Example] The present invention will be further explained below with reference to Examples.

After mixing cerium oxide (Ce02) into the urethane prepolymer, it is heated to cause a polymerization reaction, and then the polymer that has not completely solidified before completion of polymerization is passed through a sieve, and then the polymerization reaction is further carried out. The size is 3-5m.
An integrated molded product of urethane resin and cerium oxide was obtained, which consisted of irregularly shaped flakes of m. In the obtained integrated molded product, the amount of cerium oxide mixed was in the range of 0 to 40% based on the weight of the urethane resin, as shown in Tables 1 and 2.

The obtained integrated molded product was placed in a barrel tank (inner volume 7°51) to about 1/2 the level, and then water was added to moisten the integrated molded product up to the level (mass surface), and then the 100 glass balls, which were polished objects, were introduced. Each glass bulb that was introduced had a diameter of 10 mm and had been sand-polished in advance with alumina abrasive grains having a grain size of #2000.

Table 1 shows an example of polishing when a glass bulb having an abrasion m (Fl) of 150 was used as the object to be polished.

In addition, the said abrasion degree (FA) was measured as follows. That is, a sample with a measurement surface f5 of 9- is held in a fixed position on a cast iron flat plate that rotates horizontally at 60 revolutions per minute, and lbgf
Applying a load of
The abrasion weight of glass) is also measured, and the degree of abrasion is calculated using the following formula.

In the polishing examples shown in Table 1, the amount of cerium oxide mixed with respect to the weight of the urethane resin is 0%, 3%, 5%, 10%,
Using 20%, 30%, and 40% urethane resin-cerium oxide integrated moldings, polishing was carried out for 10 hours with the goal of achieving a surface roughness (Rmax) of 100 Å or less for the glass sphere to be polished. It was subjected to barrel polishing (barrel tank rotation speed 170 rpm) after repeated measurements, and as is clear from the table, the cerium oxide mixture was 0% and 3%.
%, no gloss was observed when Rm, ]x was 800 Å or more despite barrel polishing for ]OO hours. Next, in Experimental Example Nos. 3 to 7, in which the mixed amount of cerium oxide was 5 to 40%, 20 to 8
0 hour barrel polishing provides high weight accuracy and Rm8
A glass sphere with a glossy surface of less than x100 Å was obtained.

However, experimental example No. where the amount of cerium oxide mixed was 40%,
In the case of No. 7, the wear rate of the integral molding is severe, exceeding 30% after 100 hours of barrel polishing, and for this reason, it is not only difficult to carry out barrel polishing under stable conditions;
It has become clear that this method is also unfavorable from an economic point of view.

Table 2 shows a polishing example using a glass bulb with an abrasion degree (FA) of 450 as an experimental example No. as an object to be polished.

Tables 8 to 14 show examples of polishing using glass bulbs with an abrasion degree (FA>100), and Experimental Example Nos. 15 to 21 show examples of polishing using glass bulbs with an abrasion degree (FA>100).Similar to Table 1, the ratio of cerium oxide to the weight of the urethane resin is shown in Table 1. Mixing amount is 0%, 3%, 5%, 108δ, 20
%, 30%, and 40% urethane-cerium oxide integrally molded product, the surface roughness (
Barrel polishing (barrel tank rotation speed: 170 rpm) was performed with the aim of achieving a Rmax) of 100 Å or less.

In this case too, if the amount of cerium oxide mixed is less than 5%, R
It was not possible to obtain a glossy surface of less than m, x 100 Å, and 40
If the amount exceeds 5% by weight, the wear of the urethane-cerium oxide integral molded product will be severe, but if the amount of cerium oxide mixed is 5% or more,
30%, has a high degree of weight accuracy and Rmax1
It has been found that a glass bulb having a glossy surface of 00 Å or less can be obtained without abrading the urethane-cerium oxide integral molded product.

[Effects of the Invention] According to the present invention, an integrated molded product of a flexible synthetic resin and an inorganic abrasive material, in which an inorganic abrasive material is integrally bonded to a flexible synthetic resin, is used as a barrel media. By carrying out barrel polishing using the .

Claims (1)

[Claims] (1) A method for barrel polishing an inorganic hard body, which comprises barrel polishing the inorganic hard body in the presence of an integrated molded product of a flexible synthetic resin and an inorganic abrasive and water.