JPH0274675A - Needle felt for abrasion - Google Patents

Abstract

PURPOSE:To obtain the title felt of high durability excellent in abrasive grain- retentive force leading to enhancing abrasive efficiency and improving the grade of abraded surfaces by impregnating the bat of an abrasive felt main body with a cushion-forming resin containing a specific thermal reaction-type urethane resin. CONSTITUTION:The bat of an abrasive felt main body 1 made up of a base fabric B and an abrasive bat formed through needle bonding to the surface of said fabric is impregnated with a cushion-forming resin containing >=30wt.% of such a thermal reaction-type urethane resin as to effect dissociation of blocking agent at <=100 deg.C, thus forming cushion domains K with staples S forming the bat surrounded. A thermoplastic resin is then incorporated with <=20wt.%, based on the cushion-forming resin, of abrasive grain T (e.g., alumina, Al2O2, SiO2) to effect dispersion and retaining said abrasive grain followed by solidification, thus obtaining the objective felt excellent in abrasive efficiency and markedly improved in durability.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is a polishing felt suitable for use in polishing felts, particularly panel faces of television cathode ray tubes, flat glass, lenses, silicon wafers, gallium arsenide wafers, etc. This relates to felt.

[Conventional technology]

Conventional polishing felts are generally divided into two types: those that use synthetic fibers in the form of felt as is, and those that use felt processed with a resin such as porous wet urethane. Of these, the former (one that is not resin-treated) has a low polishing speed and poor surface quality of the polished surface, so methods that use resin-treated felt are becoming mainstream.

Problems to be solved by the invention C] However, conventional wet urethane resin-processed felt uses organic solvents, which leads to deterioration of the working environment.
Problems such as solvent recovery work and cleaning water treatment are common.

■For felt processed with thermoplastic resin, the resin and staples on the surface melt and form a film due to the frictional heat during polishing.
There is a risk that the abrasive grains will not be retained or that if hard foreign matter gets mixed in, the foreign matter will get caught and damage the surface to be polished.

It had such problems.

In view of the above points, it is an object of the present invention to provide a polishing needle felt that has a high polishing speed and a high quality polished surface, and is less likely to melt or form a film on staples due to friction during polishing. .

[Means to solve the problem]

In order to achieve the above object, the abrasive needle felt of the present invention impregnates the butt of the felt body with a cushion body-forming resin containing 30% or more of a heat-reactive urethane resin whose blocking agent dissociates at 100° C. or lower. In addition to filling the void around the staple with a cushioning resin, by using a block of heat-reactive urethane resin, even if the staple and thermoplastic resin melt due to the heat during polishing, the entire film will form. It is designed to prevent this.

〔Example〕

Hereinafter, the present invention will be described based on an embodiment shown in the accompanying drawings.

FIG. 1 is a diagram showing the basic structure of the polishing needle felt of the present invention in which the space around the staple is filled with a cushion body;
Figure 2 is a diagram showing the basic structure of conventional felt that does not include a cushion body, Figure 3 (a) is a diagram showing the relationship between staples and resin blocks, Figure 3 (b) is a diagram showing the principle of melting and film formation of staples, and Figure 3 (a) is a diagram showing the principle of the relationship between staples and resin blocks. Figure 4 (a) is an explanatory diagram showing the impregnation and drying process of a water-based heat-reactive urethane resin, and Figure 4 (b) is an explanatory diagram showing the impregnation and drying process of a general water-based resin.
FIG. 5 shows an experimental example of cathode ray tube polishing using a pneumatic rotating drum system, FIG. 6 shows an example of polishing using a disk system, and FIG. 7 shows an example of wafer polishing.

In the figure, 1 is a felt main body, and the main body 1 includes a base fabric 2,
It consists of a polishing bat 3 formed on the upper surface of the base cloth 2 by needling. The main body (2) has a tubular shape when polishing is performed using a pneumatic rotating drum system, and a flat plate shape when polishing is performed using a disk system. The base fabric 2 is made of a high-strength and durable woven fabric, and is capable of holding the bat 3 while withstanding the load during polishing.

The bat 3 is mainly made of synthetic fiber stable S, and can be supported by pressing the bottom of the abrasive grain toward the surface to be polished by the staples S intertwined in three dimensions. The staple S is made of thermoplastic fibers such as polyester, which is the same as that used in conventional abrasive needle felt batts, and the space filling density of the staple S before resin impregnation is about 0°1 to 0.5. ing.

Reference numeral 4 denotes a cushion body forming resin, and the cushion body forming resin 4 is used to form a cushion region surrounding the staple S to increase the abrasive grain retention ability, and is a water-based thermal reaction in which the blocking agent dissociates at 100°C or less. It is made of a resin containing 30% or more of type urethane resin U (blocked isocyanate).

Here, bisulfite having a cleavage temperature of approximately 50"C is used as the blocking agent. The cushion body forming resin 4 is impregnated into the batt 3 at a weight ratio of 10 to 60%, and foamed. - By solidifying, a cushion body K is formed which has appropriate flexibility and is composed of a group of blocks that hold the - group of staples S.

In addition, with general water-based resins used in conventional polishing needle felts, the resin migrates to the surface of the bat 3 as water evaporates during reaction hardening after impregnation, but here, the water-based resin migrates to the surface of the bat 3. Since the reactive urethane resin U is mixed into the cushion body forming resin 4, the blocking agent dissociates due to the heat during drying and becomes a three-dimensional network structure, making it difficult to cause migration (see Table 3). .

Among the constituent components of the cushion body forming resin 4, components other than the heat-reactive urethane resin U may be water-based thermosetting resins, thermoplastic resins, or latex such as resorcinol resin, polyurethane, and SBR. good. Furthermore, abrasive particles (alumina, AJ2.O, system, SiO□ system, Si
C-based abrasive particles, etc.) may be mixed in, and the abrasive particles may be replenished at any time according to the wear of the cushion material 4 during polishing.

When the batt 3 bonded by needling to the upper surface of the base fabric 2 constituting the felt body 1 is impregnated with the cushion body forming resin 4, the resin 4 is made of water-based heat-reactive urethane U.
Since it contains, migration does not occur during water evaporation, and the resin is solidified with a uniform resin distribution in the vat 3 (if abrasive particles are mixed, the abrasive particles are appropriately dispersed and supported). Further, due to the blocking effect of the heat-reactive urethane resin U, the reaction starts at about 50° C., and the cushion body K is formed by holding the staples S of the bat 3 in blocks of appropriate size.

Next, when using the polishing needle felt formed in this way and applying it to glass polishing etc. while replenishing the abrasive grain slurry, the cushion body 4 can reduce the abrasive grains compared to the conventional polishing needle felt with only staples. The holding capacity is greatly increased and the polishability is improved. In addition, even if the staple S or thermoplastic resin melts due to the frictional heat during polishing, the molten staple and resin are less likely to form a film because they are surrounded by thermosetting, heat-reactive urethane resin. Increased durability as a polishing cloth.

(Experimental example) An experiment was conducted to confirm the glass polishing property, surface quality, relationship between urethane impregnation amount and migration degree, etc. for the polishing needle felt of the present invention, and the results were shown in Table 1.2.
．． I was able to get results like 3.

From the results of this experiment, it was found that: (1) Impregnation with heat-reactive urethane resin significantly improves polishability and durability.

■If the ratio of heat-reactive resin is 30% or more, migration will be significantly less likely to occur.

■Bat staples are 0.5-6. Those within the range of Od have excellent surface quality.

etc. I found out.

■, By urethane 4'
However, A: No resin impregnation B: Heat-reactive urethane resin processing C: Double alumina abrasive grains (resin ratio 20χ) D: Double thermoplastic polyester resin E: Same 10 thermosetting resorcinol resin impregnation rate 35χ block Chemical isocyanate = Elastron E-37 (Kogyo Seiyaku type) Thermoplastic polyester resin = Bondic 1040 (Dainippon Ink Chemical Co., Ltd.) However, object to be polished = plate glass a: o, 8d b: 2. od c:6. od However, W=0.8 d, X=2d, Y=6d, Z=10
d (Both are polyester staples) However, t = Thickness of felt (mm) ◎ = Almost no migration, Good △ = Not much migration, Good × = There is migration, poor [Invention [Effects] As described above, the polishing needle felt of the present invention has the butt of the felt body impregnated with a cushion body-forming resin containing 30% or more of a heat-reactive urethane resin whose blocking agent dissociates at 100°C or lower. Because it is a feature,
A uniform cushion body can be formed on the bat without causing migration. Further, the cushion body has excellent ability to retain abrasive grains and improves adhesion to the surface to be polished, so that it is possible to increase polishing efficiency and improve the quality of the polished surface. Furthermore, even if the staples and thermoplastic resin may melt due to the heat during polishing, the staples in group - are surrounded by a thermosetting resin block, so the staples and thermoplastic resin will not form a film. , durability is greatly improved.

Therefore, dramatic improvements are realized in polishing efficiency, surface quality, and durability, which has a great effect on improving productivity and quality.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the basic structure of the polishing needle felt of the present invention in which the space around the staple is filled with a cushion body;
Figure 2 is a diagram showing the basic structure of conventional felt that does not include a cushion body, Figure 3 (a) is a diagram showing the relationship between staples and resin blocks, Figure 3 (b) is a diagram showing the principle of melting and film formation of staples, and Figure 3 (a) is a diagram showing the principle of the relationship between staples and resin blocks. Figure 4 (a) is an explanatory diagram showing the impregnation process for water-based heat-reactive urethane resin, Figure 4 (b) is an explanatory diagram showing the impregnation process for general water-based resin, and Figure 5 is a pneumatic rotating drum. Experimental example of cathode ray tube polishing by method,
FIG. 6 shows an example of polishing using the disk method, and FIG. 7 shows an example of polishing a wafer. 1--Felt body 2--Base fabric 3--Pint 4-Cushion body forming resin U--Heat-reactive urethane resin K--Cushion body S-m-Stable T--Abrasive grain F-Surface to be polished D...Disk B--Base fabric 1st kg! Fig. 2 Fig. 3 Fig. (b) Fig. 2

Claims (3)

[Claims] (1) An abrasive needle felt characterized in that the butt of the felt body is impregnated with a cushion body-forming resin containing 30% or more of a heat-reactive urethane resin whose blocking agent dissociates at 100° C. or lower. (2) The polishing felt according to claim 1, wherein the material of the cushion body forming resin other than the heat-reactive urethane resin is polyurethane, resorcinol resin, thermoplastic resin, or latex. (3) A polishing needle felt, wherein the cushion body forming resin contains abrasive grains in a weight ratio of 20% or less to the cushion body forming resin.