KR20020089657A - A combined backing for abrasive belt, and method for preparing same - Google Patents

Abstract

PURPOSE: A coupling member and a method for manufacturing the same are provided to fabricate an abrasive belt having light weight by directly coupling PET or a nylon film to a cylinder paper coated with resin solution. CONSTITUTION: Resin solution is coated on a cylinder paper in such a manner that the cylinder paper is directly coupled to a film. Resin solution includes a curing agent and one selected from the group consisting of epoxy resin, urethane resin, polyester resin, and rubber. An amount of resin solution coated on the cylinder paper is about 60-70g/m2. If the coating amount of resin solution exceeds 70g/m2, the drying time is delayed and manufacturing cost is increased. If the coating amount of resin solution is below 60g/m2, adhesive effect is lowered. The cylinder paper is coupled to the film by means of a press roller in the temperature about 65 to 75°C.

Description

Bonding base for abrasive belt and manufacturing method thereof {A COMBINED BACKING FOR ABRASIVE BELT, AND METHOD FOR PREPARING SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding base for abrasive belts and a method of manufacturing the same. More specifically, the PET or nylon film is directly bonded to a cylinder paper coated with a self-crosslinking resin solution. It relates to a method for producing a bonding substrate and a bonding substrate produced thereby.

The polishing belt is a material used in polishing processes such as plywood and MDF (medium density fiber board). In order to improve the efficiency of polishing and the rotational stability of the belt, a cotton woven fabric is usually laminated on kraft paper. A bonding base is used.

Commercially available abrasive belt substrates include, for example, a bonding substrate in which warp and weft yarns are woven into cotton in a kraft paper, such as SIAPAN 3718 from SIA, Switzerland. However, this bonding base is insufficient in tensile strength, impact durability, elongation, and adhesion of woven fabric to kraft paper, and when used in the manufacture of abrasive belts, the tear strength of the belt is liable to occur and the belt is easily stretched, so that rotational stability is improved. It was bad and there was a problem that peeling of the woven fabric and the kraft paper occurred well, and also the chemical resistance of the used cotton woven fabric was bad.

In order to improve this, Korean Patent No. 193,350 proposes a method of manufacturing a bonding base by mixing polyester blend yarns with cotton fibers. Specifically, in the Korean patent, as shown in Figure 1, the woven fabric woven with a polyester / cotton blend yarn is impregnated in the 7: 3 mixed solution of the thermosetting resin and latex, and then stretched in a warp and weft direction 150 When heated at 2 ° C. for 2 minutes and heat treated at 230 ° C. for 30 seconds, an impregnated polyester / cotton woven fabric was obtained, and when adhesiveness was imparted by applying an adhesive in which a phenolic resin and an inorganic filler were mixed in a weight ratio of 5: 5 on kraft paper. After drying to, the impregnated polyester / cotton woven fabric bonded to the kraft paper under pressure and cured, after applying and filling the adhesive on the woven fabric surface and dried for 1 hour at 90 to 120 ℃ A bonding base for abrasive belts is disclosed.

However, this method is complicated because the process of impregnating and heat-fixing the woven fabric using a thermosetting adhesive to meet the properties of the bonding base is complicated, when the manufacturing process using a polishing belt, Polishing efficiency is low, such as non-uniformity of surface roughness, and productivity is low by weight of a product. In addition, the bonding material composed of woven fabric and kraft paper is lighter than the base material for the polishing belt composed of the woven fabric alone, but still heavy, so much power is required for the replacement work of the polishing belt and thus does not provide convenience for use. In addition, the substrate for the polishing belt composed of the woven fabric alone forms a valley due to the twisting of the fiber, which is an inherent characteristic of the woven fabric, so that the abrasive powder forms a non-uniform array when the abrasive powder is coated. Or a process for filling such a valley is further performed, but it is difficult to keep the surface of the substrate for the polishing belt smooth.

Accordingly, an object of the present invention is to provide a method for producing a polishing belt base material having a high polishing productivity and a high polishing productivity, and having a smooth surface, by a simple process.

1 is a schematic diagram showing a manufacturing process of a bonding base for a polishing belt according to the prior art,

Figure 2 is a schematic diagram showing a manufacturing process of the bonding substrate for the abrasive belt according to the present invention,

3 is a view showing a cross-sectional structure of a polishing belt including a bonding substrate.

In order to achieve the above object, in the present invention, after applying a self-crosslinking resin solution to the cylinder paper, comprising bonding a film made of PET or nylon, and a method for producing a bonded base for abrasive belts and Provided is a bonding base for abrasive belts.

Hereinafter, the present invention will be described in more detail.

Bonding base material for the abrasive belt of the present invention is characterized in that the self-crosslinking resin solution is applied to the cylinder paper as an adhesive component, and then produced by bonding the cylinder paper directly to the film using the same.

The cylinder paper used in the present invention may be any conventional one used in the art, and preferably has a weight per unit area of about 400 g / m ² . The PET or nylon film is preferably a thickness of 25 to 125 ㎛, preferably about 100 ㎛.

The self-crosslinkable resin solution according to the present invention used for bonding the cylinder paper and the film includes at least one selfcrosslinkable resin and a curing agent selected from the group consisting of epoxy resins, urethane resins, polyester resins and rubber components. . The coating amount of the self-crosslinking resin solution is in the range of 60 to 70 g / m 2 based on the solid content. If the coating amount is more than 70 g / ㎡ it takes a long time to dry and cost increases, if less than 60 g / ㎡ has the disadvantage that the adhesive effect is not sufficient.

The self-crosslinking resin is heat-melt or alcohol-solvent, crosslinking occurs by the curing agent component even at room temperature drying to form a tacky coating film, the drying time is about 40 to 60 seconds. The self-crosslinking resin does not need to be heated during drying because it crosslinks even at room temperature, but may serve as an adhesive, and thus plays a crucial role in shortening the manufacturing process and providing stability of the cylinder paper. Methanol, ethanol, isobutanol and the like may be used as the alcohol.

The bonding process of the self-crosslinking resin-coated cylinder paper and the film is performed by a pressure roller at a temperature of 65 to 75 ℃. Since the bonding process is performed at a temperature below the heat deformation temperature of PET or nylon, which is a raw material of the film, that is, at a relatively low temperature, an increase in elongation and a decrease in tear strength due to heat shrinkage of the film can be prevented.

An abrasive belt may be manufactured by applying an abrasive to a bonding substrate according to the present invention in a conventional manner. Specifically, after the two-component urethane adhesive is pre-sized onto the film surface of the base for the polishing belt, a powder-type abrasive is applied and pre-dried, and then thermosetting resins such as phenol resins and epoxy resins are used as adhesives. It can be obtained by sizing again, drying and curing. As the abrasive, those known in the art may be used, and specific examples thereof include alumina, silicon carbide (SiC), alumina zirconia, or a mixture thereof. The cross-sectional structure of a conventional polishing belt is shown in FIG. The abrasive belt includes a base 1, a primary adhesive 2, an abrasive 3, and a secondary adhesive 4.

Bonding substrate according to the present invention is excellent in the physical properties such as tensile strength, tear strength, elongation, it is possible to provide excellent polishing and productivity and a lightweight abrasive belt.

The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Comparative Example 1

A substrate for an abrasive belt was manufactured using the apparatus shown in FIG. 1 by the method described in Korean Patent No. 193,350.

Specifically, from the container 6 'containing the adhesive 5' in which the phenol resin and the calcium carbonate as the filler are mixed in a 5: 5 weight ratio, the adhesive 5 'is used by using rollers 3' and 4 '. Was applied to kraft paper 2 '(thickness: 0.48 mm) and then dried to provide adhesiveness while being transported through roller 7'. Then, a polyester / cotton blended woven fabric (thickness: 0.37 mm) was impregnated in a 7: 3 mixed solution of phenol resin and latex, stretched and heat treated (150 ° C., 2 minutes), and then unrolled (1 '). It was combined with the kraft paper 2 'to which the adhesive was applied by rollers 8' and 9 'with introduction. In this case, the weight per unit area of the impregnation liquid was 1.50 to 1.60 g / m 2, and the total thickness of the woven fabric and the impregnation liquid thus formed was 0.86 mm. Subsequently, the binder was applied to the woven fabric surface by rollers 12 'and 13' through a roller 10 ', and then dried in a dryer 14' for 1 hour at 90 to 120 ° C. In this way, a bonding base (thickness: 1.25 to 1.35 mm) for an abrasive belt was manufactured.

Example 1

Using the apparatus shown in Figure 2 was prepared for the bonding base for the abrasive belt according to the present invention.

The cylinder paper (unit weight 400 g / m 2) supplied by the unwinding roll 1 was prepared by self-crosslinking urethane resin adhesive 6 [100 parts of 80% solution of urethane resin having an average molecular weight of 8000 to 10000 and an epoxy group-containing curing agent (200 to 300). Equivalent) 35 parts, containing a viscosity of 2,500 to 3,500 cps at 25 ± 2 ° C.] and introducing the surface of the paper with the adhesive 6 through the calender roll 3 and the gravure roll 4. After coating, it was introduced into the dryer 11 via a driving roll 7 and dried at a temperature of 50 ° C. or lower, and then pressed together with a polyester film (thickness: 100 μm) supplied by the unwinding roll 2. Bonding while passing through rolls 8 and 9 yielded a film / cylindrical paper bonding substrate and wound up on a take-up roll 10.

Subsequently, in the apparatus as shown in FIG. 1, the base material was applied to the unrolling roll 1 'to apply a two-component urethane adhesive [100 parts of a 60% solution of a urethane resin with an average molecular weight of 10,000 to 15,000 containing NCO groups and 100 parts of an OH group 25 parts of a curing agent], and dried for about 45 minutes at 80 to 140 ℃ to obtain a bonding base for the abrasive belt according to the present invention.

Example 2

A bonding substrate was prepared in the same manner as in Example 1, except that a nylon film (thickness: 100 µm) was used instead of the polyester film.

Example 3

Self-crosslinking resin solution, in place of urethane resin adhesive, containing 100 parts of epoxy resin adhesive [400-450 equivalents of 75% solution of epoxy resin 75% and 25 parts of 70% solution of amine-based curing agent (amine value 300-350) at 25 ± 2 ° C. A bonding substrate was prepared in the same manner as in Example 1, except that the viscosity was used at 3,000 to 3,500 cp].

Test Example 1: Property Test

Various physical properties were measured for each of the polishing belt bonding substrates obtained in Comparative Example 1 and Examples 1 to 3, and the results are shown in Table 1 below.

The test method was performed according to KS K 0536, KS K 0520 and KS K 0533.

Test Items Comparative example Example 1 Example 2 Example 3 Tensile strength (kgf / in) 85 120 100 120 Tear strength (gf / 43mm) 1,800 4,000 3,000 4,000 Elongation (%) 14.0 2.0 3.0 2.0 Surface Roughness (R _MAX ) 105 9.8 10.0 9.9 Weight (g / m ² ) 1,800 1,000 980 1,080 Adhesion of Bonding Materials (kgf / 2inch) 25 ∞ ∞ ∞

As shown in Table 1, the substrate for the polishing belt prepared in Examples 1 to 3 is superior to the substrate prepared by the comparative example, the tensile strength and tear strength is excellent, and also excellent in elongation, surface roughness and adhesive strength It was excellent and lighter.

Test Example 2: Polishing ability and productivity test

An abrasive belt (belt size: 2650 mm × 3200 mm) was manufactured by bonding silicon carbide as an abrasive to the adhesive surface of the substrate obtained in Comparative Example 1 and Examples 1 to 3 in a conventional manner. In this case, silicon carbide was # 60, # 80 and # 120, in each case was used in amounts of 350 g / ㎡, 290 g / ㎡ and 250 g / ㎡, respectively.

Using the abrasive belt, the grinding performance and productivity were tested for MDF (size: 8 ft × 24 ft × 18 mm) as a grinding material in the three-head grinding machine under the following grinding conditions, and the results are shown in Table 2 below. :

<Grinding condition>

1st head contact roll: # 60, 2nd head contact roll and pad: # 80, 3rd head pad: # 120

First belt speed: 2000 m / min, second and third belt speeds: 1375 m / min

Working speed: 15 m / min

First head grinding amount: 1.0-1.1 mm thick, Second and third head grinding amount: 0.2-0.3 mm thick

Test Items Comparative Example 1 Example 1 Example 2 Example 3 Effective grinding time (hours) 24 48 46 48 Number of grinding pieces polished per hour (long) 1,200 2,400 2,200 2,350 Surface roughness after polishing (center line surface roughness: R _а , ㎛) 7.3 2.25 2.26 2.30

As shown in Table 2, the abrasive belt substrates prepared in Examples 1 to 3 increased the effective grinding period and productivity more than two times compared to the substrates prepared by the Comparative Example, and the surface roughness after grinding of the abrasives. It can provide excellent grinding products with more than 70% lower.

According to the present invention, by directly bonding a PET or nylon film to a cylinder paper coated with a self-crosslinking resin solution, it is possible to manufacture a bonding base for an abrasive belt having excellent physical properties such as tensile strength, tear strength, and elongation by a simple process. In the case of manufacturing the abrasive belt using this substrate, the productivity by the grinding ability and the weight reduction of the product can be greatly improved.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (6)

In the cylinder paper, magnetism obtained by dissolving at least one self-crosslinking resin component and a curing agent component selected from the group consisting of an epoxy resin, a urethane resin, a polyester resin and a rubber component in an alcohol selected from the group consisting of methanol, ethanol and isobutanol After applying a self-crosslinking resin solution, comprising the step of bonding a film made of PET or nylon, the manufacturing method of the bonding base for the abrasive belt. The method of claim 1, The cylinder paper is characterized in that the weight per unit area is 400 g / ㎡. The method of claim 1, The coating amount of the self-crosslinking resin solution is 60 to 70 g / ㎡ based on the solid content. The method of claim 1, The film is 25 to 125 μm thick. The method of claim 1, Process for bonding the self-crosslinked resin coated cylinder paper and PET or nylon film is carried out at 65 to 75 ℃. A bonding base for a polishing belt produced by the method of any one of claims 1 to 5, in which a cylinder paper, a self-crosslinking resin adhesive, and a PET or nylon film are sequentially laminated.