MXPA99009782A

MXPA99009782A - Abrasive material and method of forming same

Info

Publication number: MXPA99009782A
Application number: MXPA/A/1999/009782A
Authority: MX
Inventors: Pollasky Anthony
Original assignee: Pollasky Anthony
Priority date: 1998-02-27
Filing date: 1999-10-25
Publication date: 2000-07-01

Abstract

The present invention provides an abrasive material (50) comprising a base surface having a plurality of pyramidal shapes protruding therefrom the base surface and the protrusions (52) being formed of the same material, each protrusion (52) having a substantially triangular, square, or polygonal base and triangular sides which meet at an apex which substantially forms a point. The protrusions (52) provide intermixed cutting and planning edges in a pattern such that the material (50) is capable of abrading independent of direction of use. A coating (56) is applied to improve abrasive performance and reduce surface porosity. A method of forming the abrasive material (50) is also provided.

Description

ABRASIVE MATERIAL AND METHOD OF EDUCATION The present invention relates to an abrasive material produced by an etching process and suitable for sanding or polishing a variety of surfaces and to a method of forming the abrasive material.

Several abrasion surfaces have been suggested over the years. Such surfaces include those in which the abrasive particles, such as garnet, aluminum oxide, silicon carbide, zirconia edge grain and alpha-aluminum oxide monohydrate, only diamond or cubic boron nitride crystals adhere to a substrate. . Abrasive surfaces are also known, which are marked with cuts to provide grooves or perforate to provide holes or openings with projections or roughness surrounding the holes. Where the grooves have been formed into metal sheets, such as steel sheets, the coating of the surface or the cutting edge formed by the groove is also known. The metallic abrasive blades are known, which are prepared by forming a negative galvanic of cured polyvinyl chloride using a sheet of abrasive paper and then electroplating the electroplate to form the sheet.

Ref. 031883 Acid etching processes using an appropriate protective layer to form a desired pattern on a metal substrate are also known. In such a technique, a pattern of the protective layer is applied to a flat, thin steel plate in a predetermined pattern, such as sites of equal size, which may be round, elongated or polygonal. The plate is etched by etching, in which a etching acid such as an aqueous solution of ferric chloride removes the desired amount of metal and forms the standard elements. It is reported that through the variations of the spraying, composition and temperature mode of the etching solution, the angle between the side of the protruding cutting elements and the surface of the original plate, as desired as to where, under the edge of the protection pattern elements, etching will be achieved. A suggested improvement is to provide parallel flanges on the etched side of the plate in the form of rhombic quadrilaterals either tangentially or helically to prevent ripple plate.

Another suggested improvement is a pattern of the protective layer which is reported to give a uniform intermixing of well-defined points of rapid work with smooth brushing edges. The cutting teeth are formed in the form of triangles or squares, which leave the etching process, still well defined and usable due to the pattern of the protective layer, which accentuates the angular points and is eliminated under the cut of the upper surfaces of the cutting teeth. Each tooth has an upper flat surface and is docile to hardening by heat treatment without excessive brittleness due to the configuration of the tooth. The upper planar surface of each tooth is reported to be typically about 3 mils with the width of the base and the height of the tooth being approximately twice that of the upper planar surface.

A process for producing cutting molds, particularly for use such as, for example, cutting tape to form labels, has been described where multiple acid etching steps are used. A protective layer corresponding to the contour of a label that is characterized is formed in a steel plate and a first etching step is carried out, therefore a convex portion of a prescribed height is formed. A second step of acid etching is carried out, by means of which the protective layer extending from both sides of the upper part of the convex portion is removed and the steel plate is subjected to additional etching. This second step of acid etching can be carried out multiple times. Then the protective layer that remains on top of the convex portion is removed.

BRIEF DESCRIPTION OF THE INVENTION The present invention, in one aspect, provides an abrasive material comprising a base surface having a plurality of pyramidal shapes protruding from the same base surface and the protrusions being formed from the same material, each protrusion having a triangular, square base , or substantially polygonal and triangular sides which are joined at a vertex, which substantially forms a point, the projections provide cutting and brushing edges intermixed in a pattern, such that the material is capable of abrasion independent of the direction of use and a coating applied to the base surface and projections to improve abrasive performance and reduce surface porosity.

The coating applied to the base surface and projections to improve abrasive performance and reduce surface porosity can vary widely. Typical coatings include nickel or chromium metallization or a diamond coating or metallization in combination with diamond powder or boron nitride. The surface of the projections can be treated with heat to improve hardness as is well known to those skilled in the art.

Preferably, the triangular sides of the pyramidal projections have an internal arched inclination. Such inclination provides greater longevity of the abrasive material due to the lack of load of the material that is worn by friction. The present invention provides a rapid removal of material from a workpiece, it still leaves a smooth surface on the workpiece. The abrasive material of the invention can be provided with projections on both surfaces of the base material to prevent curling when the material is thin.

The present invention, in a further aspect, provides a method of forming an abrasive material comprising the steps of: (a) provide a base material; (b) applying a coating of photosensitive protective substance to at least one surface of the base material; (c) placing on the photosensitive protective substance a mask having a triangular, square or polygonal randomly directional pattern thereon; (d) applying a suitable etching acid to etch the base material for a time sufficient to provide a plurality of pyramidal projections on the base surface, each projection having a substantially triangular, square or polygonal base and triangular sides which they join in a vertex, which substantially forms a point: (e) removing the mask and the unexposed photosensitive protective substance from at least the etched surface; (f) apply a coating to the surface to reduce surface porosity and improve abrasion performance.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1, lb, and are seen in perspective of the pyramidal projections useful in the invention.

FIG. 2 is a perspective view of a preferred pyramidal projection of the invention having internal curved triangular sides.

FIG. 3 is a top view showing an appropriate pattern of the pyramidal projections for use in the abrasive material of the present invention.

FIG. 4a is a top view of a pattern of the photosensitive protective substance suitable for use in producing an abrasive material of the invention.

FIG. 4b is a top view of an enlarged portion of the pattern of the photosensitive protective substance shown in FIG. 4a.

FIG. 5 is a side view of a pyramidal projection useful in the invention having a hard coating thereon.

FIG. 6 is a fragmented cross section of an abrasive material of the present invention having pyramidal projections on each surface thereof.

DETAILED DESCRIPTION OF THE INVENTION The abrasive material of the invention can be formed of any material susceptible to etching which includes, for example, stainless steel, carbon steel, aluminum alloys, iron-nickel-chromium alloys, and titanium.; boron-laden elastomers, silica compounds, fluorocarbon materials, graphite alloys, plastics, and the like. The thickness of the material is not particularly limited, but after etching it must be appropriately flexible where it will be used on a roller or appropriately rigid when used as a flat abrasive. Of course, rigidity can be provided, if necessary, by attachment to a rigid substrate such as, for example, a metal plate or synthetic resin plate having an appropriate stiffness.

With respect to the drawings, the number of the like references will be used with reference to the equal parts. FIGS. lb, and describe various possible embodiments of the pyramidal projections of the abrasion material of the invention with the bases of the pyramidal projections being triangular, square and pentagonal, respectively. Of course, other polygonal shapes can be used. In FIG. the projection 10a is shown to have a triangular base 12a, a triangular side 14a, and a vertex 16a. In FIG. lb, the projection 10b is shown to have a square base 12b, a triangular side 14b and a vertex 16b. In FIG. The projection 10c is shown to have a polygonal base 12c, a triangular side 14c and a vertex 16c.

The vertex of each necessary projection does not form a true point as shown in FIGS. , although this is the preferred configuration. The vertices of the projections may be slightly round or flat. However, this portion of the vertices preferably should not be greater in width than 20 percent of edges L, more preferably not more than 10 percent of edges L, edges L are shown in FIG. 5.

The depth of the internal arched inclination on the triangular sides of the pyramidal projections, which are found in the preferred embodiments of the invention can be from very light, for example, lμm, to as large as approximately 175μm. Such arched inclinations can be easily seen in FIGS. 2 and 3, wherein the projection 20 has arched inclined surfaces 22. The greater of the size of the projections, the deeper of the internal curved inclination can be formed.

Preferably, the height H of the pyramidal projections of the surface etched by etching may be in the range of about 25 μm to 1.5 mm, with higher pyramidal protrusions for normal rough abrasion, i.e., from about 125 μm to 375 μm , and lower pyramidal projections for a finer abrasion, that is, from about 75 μm to 125 μm. The length of the edges L of the base is dependent on the height of the projections. Preferably, the ratio of the height of the protrusions from the surface etched to the edge length of the base is in the range of about 1: 1 to 1: 5, more preferably about 1: 2 to 1: 4, more preferably about 1: 3. The thickness of the remaining base material B can vary widely and is not critical, with thinner base materials that are used for more flexible abrasive materials and thicker base materials that are used for more rigid abrasive materials as is well known to those experts in the art. Such dimensions are indicated in the enlarged view of a portion of a hard coated abrasive material, seen in cross section in FIG. 5.

The spacing S of the pyramidal projections can also vary widely, from about 0.75 mm to 30 mm apart, measured from center to center of the circular pattern, with greater spacing for rough abrasion, i.e. 2 to 10 mm or greater apart and smaller spacing for the finer abrasion, that is, from about 0.75 to 1.5 mm apart. A pattern of the appropriate protective layer for a medium abrasive edge grain is shown in FIG. 4a. An enlarged portion of the pattern of the protective layer is shown in FIG. 4b to show the pattern detail.

The fineness or roughness of the abrasive material can also be adjusted by keeping the height of the protrusions and the length of the base of the protrusions and adjusting the size of the pattern of the protective layer. The greater spacing between the protrusions provides a rougher abrasion material, while a smaller spacing between the protrusions provides a finer abrasion material.

It is important that the pyramidal projections are oriented such that the cutting edges of the individual projections are oriented in different directions to provide the abrasion capacity independent of the direction of use. The pyramidal projections can be oriented randomly in several directions, such as by assigning the acid etching mask through the use of a computer-based random generator or etching mask can be modeled, which ensures random orientation as is well known to those skilled in the art. An example of a randomly oriented pattern is shown in FIGS 4a and 4b. In FIG. 4a, a portion of the mask pattern is shown in greater detail with a portion of the cured protective layer 42 which provides the desired protrusions after etching.

As previously described, a coating such as nickel or chromium plating; a diamond coating; or metallization with nickel or chromium in combination with diamond powder or Teflon®, tungsten, carbide particles or boron nitride can be applied to the surface of the abrasive material, as shown in FIG. 5, wherein a portion of the abrasive material 59 has a projection 52, a remaining base material 54, and a coating 56.

The etching process can be carried out using a well-known protective layer and etching materials. The protective layer can be applied using, for example, hot roll lamination, stencil printing, gravure printing, dip coating and the like. For example, when the substrate is stainless steel, carbon steel, or the like, suitable etching acids include ferric chloride, hydrochloric acid, nitric acid or mixtures thereof; for aluminum or aluminum alloys, suitable etching acids include sodium hydroxide; for titanium, suitable ethers include hydrofluoric acid; and plastics are usually etched by chemical attack using various acids. The degree of etching can be adjusted by altering the concentration and temperature of the acid solution for etching and the method of application as is known to those skilled in the art. For example, when the base material, or substrate, is stainless steel, an aqueous ferric chloride solution of approximately 42 ° to 50 ° Baumé, the lowest Baumé grade of the solution, generally the most arcuate of the solution, can be used. inclination of the sides of the projections.

After etching, the protective layer can be removed by techniques well known to those skilled in the art. Alternatively, the protective layer can be maintained on the surfaces of the laminate, particularly on the non-abrasive side of the material when only one side is masked and the pattern is etched, which helps in the prevention of curling. An appropriate method of curl prevention comprises etching of both surfaces of the base material as shown in FIG. 6, wherein the abrasive material 60 has projections 62 in house surface 61, 63 extending from the remaining base material 64.

The objects and advantages of the invention are further illustrated by the following examples, but the materials and amounts thereof cited in these examples, as well as the conditions and details, are not constructed to unduly limit this invention. All parts and percentages are by weight unless otherwise indicated.

EXAMPLES Example 1 A stainless steel sheet approximately 250 μm thick was rinsed with dilute nitric acid and rinsed with water to remove any of the oils present on the surface. A photosensitive protective substance, AX15 available from Morton Co. , it was coated on the surface to produce a dry coating approximately 39 μm thick. A mask having a pattern similar to that of FIG. 4a, but transparent in the areas shown as black, was placed on the photosensitive protective substance. This compound was exposed to ultraviolet light to effect the cure of the photosensitive protective substance. The mask was removed and the unexposed photosensitive protective substance was removed by rinsing with Developer KB1A, available from Morton Co., leaving a mask pattern similar to that of FIG. 4a. An aqueous ferric chloride solution of about 42 ° Baumé was applied to the surface by spraying for about 11 minutes at about 50 ° C to etch the exposed steel surface. The etched leaf was rinsed with water to suspend etching.

The pyramidal projections had a triangular base, each edge of which was approximately 400 μm. The height of the projections was approximately 150 μm with internal curved faces with maximum notches of approximately 25 μm. The resulting sheet had only a slight tendency to curl due to the protective layer that is allowed to remain on the surface not etched by chemical etching. When restricted in a flat position, the resulting sheet is excellently made in a manner similar to the abrasive paper of 180 awned grain, but without typical loading problems with the abrasive paper.

A portion of the sheet was metallized with chromium to achieve a chromium thickness of approximately 5 μm. This product exhibited excellent abrasive performance with low load and good longevity.

Example 2 An abrasive stainless steel sheet was prepared as in Example 1, except that both surfaces of the stainless steel sheet were treated to provide pyramidal projections therein. Abrasive performance was found excellent and the sheet did not exhibit curling.

Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope or spirit of this invention, and it should be understood that this invention is not unduly limited to the illustrative embodiments shown herein.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, the content of the following is claimed as property.

Claims

1. An abrasive material, characterized in that it comprises a base surface having a plurality of pyramidal shapes protruding from the same base surface and the protrusions are formed of the same material, each protrusion having a triangular, square or polygonal base substantially and triangular sides the which join at a vertex, which substantially forms a point, the projections provide cutting and brushing edges intermixed in a pattern, such that the material is capable of abrasion independent of the direction of use and a coating applied to the surface of base and projections to improve abrasive performance and reduce surface porosity.

2. The abrasive material according to claim 1, characterized in that the projections have a height of about 25 μm to 1.5 μm.

3. The abrasive material according to claim 1, characterized in that the projections have a height of about 125 μm to 375 μm.

4. The abrasive material according to claim 1, characterized in that the projections have a height of approximately 75 μm to 175 μm.

5. The abrasive material according to the claim 1, characterized in that the ratio of the height of the projections from the etched surface to the length of the base of the projections is approximately 1: 1 to 1: 5.

6. The abrasive material according to the claim 1, characterized in that the proportion of the height of the projections from the etched surface to the length of the base of the projections is approximately 1: 2 to 1: 4.

7. The abrasive material according to claim 1, characterized in that the ratio of the height of the protrusions from the etched surface to the length of the base of the protrusions is approximately 1: 3.

8. The abrasive material according to claim 1, characterized in that the triangular sides of the pyramidal projections have an internal arched inclination.

9. The abrasive material according to claim 8, characterized in that the depth of the internal arcuate inclination is approximately 1 μm to 175 μm.

10. The abrasive material according to claim 1, characterized in that the material is provided with projections on both surfaces of the base material.

11. The abrasive material according to claim 1, characterized in that the material has projections on one surface thereof and a photosensitive protective substance on the other surface thereof.

12. The abrasive material according to claim 1, characterized in that the base material is stainless steel, carbon steel, aluminum alloy, iron-nickel-chromium alloy, titanium, boron loaded elastomer, silica compound, fluorocarbon materials , graphite alloys, or plastic.

13. The abrasive material according to claim 1, characterized in that it also comprises a surface coating.

14. The abrasive article according to claim 13, characterized in that the surface coating is metallized with chromium or nickel.

15. The abrasive material according to claim 13, characterized in that the surface coating is diamond.

16. The abrasive material according to claim 13, characterized in that the surface coating is metallized with chromium or nickel containing diamond powder or Teflon®, tungsten, carbide particles or boron nitride.

17. A method of forming an abrasive material, characterized in that it comprises the steps of: (a) provide a base material; (b) applying a coating of photosensitive protective substance to at least one surface of the base material; (c) placing on the photosensitive protective substance a mask having a triangular, square or polygonal randomly directional pattern thereon; (d) applying a suitable etching acid to etch the base material for a time sufficient to provide a plurality of pyramidal projections on the base surface, each projection having a substantially triangular, square or polygonal base and triangular sides which they unite in a vertex, which substantially forms a point; (e) removing the mask and the unexposed photosensitive protective substance from at least the etched surface; 2 (f) apply a coating to the surface to reduce surface porosity and improve abrasion performance.

18. The method according to claim 17, characterized in that the base material is stainless steel, carbon steel, aluminum alloy, titanium, boron loaded elastomer, silica compound, fluorocarbon material, graphite alloy or plastic.

19. The method according to claim 17, characterized in that the protective layer is applied using hot roll lamination, stencil printing, gravure printing or dip coating.

20. The method according to claim 17, characterized in that the acid for etching is ferric chloride, hydrochloric acid, nitric acid, sodium hydroxide or hydrofluoric acid.

21. The method according to claim 17, characterized in that the material is stainless steel and the etching acid is aqueous ferric chloride from 42 ° to 50 ° Baumé.