GB2164053A

GB2164053A - Heat-resistant flexible abrasive member and method of preparation

Info

Publication number: GB2164053A
Application number: GB08514169A
Authority: GB
Inventors: Joseph Lazar; Alexander Schwartz
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-03-25
Filing date: 1985-06-05
Publication date: 1986-03-12
Also published as: GB8514169D0; BR8601537A

Abstract

The disclosure describes the preparation of a heat-resistant flexible abrasive member. The method comprises applying to a heat-resistant flexible stretch-free fabric (3), such as a polyester cloth, an adhesive (7) which is not affected or distorted by heat, solvent or water, does not dry and crack, and retain flexibility when cured. A polyurethane adhesive is a good example. A flexible abrasive member (5) is then laminated onto the adhesive containing flexible stretch- free fabric. The adhesive is allowed to cure and bond both the stretch- free material and the flexible abrasive member, thereby providing a material with a backing which withstands heat generated by friction against materials to be abraded. <IMAGE>

Description

SPECIFICATION Heat-resistant flexible abrasive member and method of preparation Description This invention relates to a heat-resistant flexible abrasive member, and a method of preparing the same. More particularly, the invention relates to the manufacture of a flexible, dryrunning diamond abrasive surface, such as an abrasive belt or disc, which is provided with a backing that will withstand heat generated by friction against materials to be abraded on the one hand, and against the pressure plate, in the case of a backing plate, on the other hand.

b) Description of Prior Art Grinding and abrading are important industrial processes which are becoming more and more important. When applied to extremely hard materials, such as glass, these processes rely heavily on diamond. For example, one can use a flexible abrasive coated member, such as the one described in U.S. Patent No.

4,256,467, issued March 17, 1981, inventor lan Gorsuch, to make abrasive belts or discs.

However, this material is not very sturdy and heat-resistant with the result that it cannot be used to satisfaction to manufacture grinding or abrading belts or discs. There is therefore a need for a belt, a disc or other grinding members which are heat-resistant while being flexible.

According to the present invention, there is provided a method of preparing a heat-resistant flexible abrasive member, which comprises providing a heat-resistant flexible stretch-free fabric, applying to the fabric an adhesive which is not affected or distorted by heat, solvent or water, does not dry and crack, and retain flexibility when cured, laminating a flexible abrasive member onto the flexible stretch-free fabric having the adhesive thereon, and allowing the adhesive to cure and bond both the flexible stretch free material and the flexible abrasive member. This will provide a material with a backing which withstands at least heat generated by friction against materials to be abraded.

According to a preferred embodiment of the invention, the flexible stretch-free fabric is in the form of a band, the flexible abrasive member has a shape to conform to the band and the resulting flexible abrasive member consists of an abrasive belt.

If it is intended to prepare a continuous belt, the ends of the belt are joined together such as by splicing, for example by a process which involves a heat resistant reinforced tape. The tape may have a thickness which varies between about 3 and 7 millimeters.

Preferably, a tape such as MYLARTM or KEVLARTM is used.

In accordance with a preferred embodiment - of the invention, the ends are shaped to wave like form and to fit substantially one another.

The tape is then applied at the ends by means of the adhesive, and a perfect unbreakable joint is thereby formed.

Although the nature of the material can vary to a large extent, a polyester cloth is preferred for the excellent results obtained. The polyester cloth may be calendered, and may contain a filler, which can bk a clay-like substance. The polyester cloth preferably has a surface capable of insuring adhesion to the adhesive, such as by being provided with a phenolic resin coating thereon.

The preferred adhesive is a polyurethane adhesive, which may be a two part adhesive including a curing agent. The adhesive per se may consist of BOSTICK 7070TM and the curing agent may be BOSKADURTM.

The usual but not exclusive flexible abrasive member is a polyester cloth having a diamond abrasive therein, which may be nickel plated onto the polyester cloth. One interesting flexible abrasive member comprises a flexible non electrically conductive mesh material, a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having diamond crystals embedded therein.

The flexible stretch-free fabric may be in the form of a disc, in which case the flexible abrasive member has a shape to conform to the disc and the resulting flexible abrasive member consists of an abrasive disc.

According to another embodiment of the invention, a vinyl coating may be applied along the edges of the band so as to provide smooth slippery parallel outer edges along the entire band. In this case, the flexible abrasive band is selected to cover only the area of the flexible stretch-free fabric not covered by the vinyl coating.

According to a preferred embodiment of the invention, the heat-resistant flexible abrasive member is transversely curved to prevent a glass edge to touch extreme outer edges of the belt as the two are moved towards one another. This will enable the glass edge to be abraded as soon as glass enters from the side of the belt.

A specific embodiment according to the invention is a method of preparing a heat resistant flexible adhesive belt which comprises providing a heat-resistant flexible stretch-free band of calendered polyester cloth, which has a phenolic resin coating thereon, applying to the polyester cloth a two part polyurethane adhesive including a curing agent, the adhesive consisting of BOSTICK 7070TM and the curing agent consisting of BOSKADURTM. The next step involves laminating onto the polyester cloth an abrasive member comprising a flexible non electrically conductive mesh material, a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having powdered diamond embedded therein.The adhesive is allowed to cure and to bond both the polyester cloth and the flexible abrasive member. The ends of the belt are cut in wave like form so as to fit substantially with one another. Some of the two part polyurethane adhesive is applied at the wave like ends which are joined to form a joint. Additional adhesive is applied along the joint and a MY LARTM or KEVLARTM tape is applied at the joint and the assembly is pressed to give a uniform joint.

The invention also relates to a heat resistant flexible abrasive member which comprises a heat-resistant flexible stretch-free fabric and a flexible abrasive member which is laminated onto the fabric by means of an adhesive which is not affected or distorted by heat, solvent or water, does not dry and crack, and retain flexibility when cured.

Specifically but not exclusively, the invention relates to an endless heat resistant flexible abrasive belt, which comprises a heat-resistant flexible stretch-free band of calendered polyester cloth, having a phenolic resin coating thereon, an abrasive member laminated onto the polyester cloth by means of a polyurethane adhesive including a curing agent, consisting of BOSTICK 7070TM and BOSKADURTM.

The abrasion member comprises a flexible non electrically conductive mesh material, a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having powdered diamond embedded therein. The ends of the belt are in wave like form so as to fit substantially with one another, and are joined together by means of some of the same two part polyurethane adhesive applied at the wave like ends. The wave like form ends are additionally spliced together by means of additional polyurethane adhesive and there is a MYLARTM or KEVLARTM tape over the joint.

The invention is illustrated but not restricted by means of the following drawings, in which: Figure 1 is a perspective view of an abrasive belt according to the invention; Figure 2 is a transverse cross-section, on a large scale, through the belt illustrated in Fig.

1; Figure 3 is a view of an abrasive belt according to the invention which has been transversely curved; and Figure 4 is a partial view of another embodiment wherein the lateral edges are plastic coated.

Referring to the drawings, the belt 1, as shown is flexible and endless. It generally comprises a heat-resistant flexible stretch-free band 3 of calendered polyester cloth which is laminated with an abrasive band 5 by means of an adhesive 7. To ensure a good adhesion of the polyester cloth to the adhesive which will be defined later, the polyester cloth has a phenolic resin coating on the face which is intended to receive the adhesive. Of course, it is understood that any other treatment which will cause the adhesion of the adhesive to the polyester cloth, and which is known to those skilled in the art, falls withintthe scope of the present invention.Although the thickness of the band 3 of polyester cloth is not critical as long as it can produce the intended product, a belt 1 in the case illustrated, it has been found that best results will be obtained when the thickness of the polyester cloth varies between about 0.02 mm and 5 mm.

The abrasive band 5 which is laminated onto the polyester cloth 3 is essentially a flexible non electrically conductive mesh material as described in U.S. Patent No. 4,256,467.

The mesh material has an abrasive face 9 which is made of a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the latter is embedded in the nickel layer. In addition, the nickel layer has diamond crystals embedded therein.

The adhesive which is used to laminate the abrasive band 5 onto the band 3 of polyester cloth must not be affected or distorted by heat, solvent or water. Furthermore, once cured, the adhesive must not dry or crack and should retain flexibility. In practice, it has been found that excellent results have been obtained when using a two part polyurethane adhesive. For example, the adhesive part may consist of BOSTICK 7070TM which is a polyurethane rubber solution sold by EMHART.

The second part is a curing agent and excellent results have been obtained using BOSKA DURTM also sold by EMHART.

The ends 11 and 13 of the belt are cut in wave like form as shown in Fig. 1 so as to form just about a perfect fit with one another.

The ends 11 and 13 are joined together by means of the same adhesive as defined above and the joint 15 is formed by splicing the ends 11 and 13 and covering the joint 15 on the inner face of the belt 1 with a heat resistant reinforced tape, such as by using a MY LARIM or KEVLARTM tape 16.

In the embodiment illustrated in Fig. 3, the belt is transversely curved. This can be accomplished by rolling the belt between shaping rollers, as is well known to those skilled in the art. This arrangement will prevent, for example, a glass edge to touch the extreme outer edges 21,23 of the belt 1, as the two are moved towards one another, and will enable the glass edge to be abraded as soon as the glass enters from the side of the belt after having passed over edges 21,23 without touching either of them.

Another embodiment according to the inven tion is illustrated in Fig. 4. According to this embodiment, there are longitudinal parallel outer strips 17,19 of a vinyl coating along the edges of the band 3 of polyester cloth on the outer-face thereof. Such coating provides smooth slippery parallel outer edges along the entire band. This will help in preventing damage to the edges of the belt when abrading articles with sharp edges. Of course, in this case, the flexible abrasive band 9 should be shaped to cover only the area of the flexible stretch-free fabric 5 not covered by the vinyl coating 17,19.

The manufacture of the belt according to the invention is straightforward. It is merely sufficient to apply the adhesive 7 to the fabric 3 and to laminate the abrasive member 5 thereon by any known means. The adhesive is allowed to cure and to bond both the fabric 3 and the abrasive member 5.

The invention is of course not restricted to a belt. For example, a disc or any other grinding or abrading tools can be produced by the method according to the invention.

Claims

1. Method of preparing a heat-resistant flexible abrasive member, which comprises: providing a heat-resistant flexible stretch-free fabric, applying to said fabric an adhesive which is not affected or distorted by heat, solvent or water, does not dry and crack, and retain flexibility when cured, laminating a flexible abrasive member onto said flexible stretch-free fabric having said adhesive thereon, and allowing said adhesive to cure and bond both said flexible stretch free material and said flexible abrasive member, so as to provide a material with a backing which withstands at least heat generated by friction against materials to be abraded.

2. Method according to claim 1, wherein said flexible stretch-free fabric is in the form of a band, said flexible abrasive member has a shape to conform to said band and the resulting flexible abrasive member consists of an abrasive belt.

3. Method according to claim 2, which comprises joining ends of said belt to provide a continuous belt.

4. Method according to claim 2, wherein said ends are joined by splicing.

5. Method according to claim 4, wherein said splicing involves the use of a heat resistant reinforced tape.

6. Method according to claim 5, wherein said tape has a thickness which varies between about 3 and 7 millimeters.

7. Method according to claim 6, wherein said tape is selected from the group of MY LARTM and KEVLARTM.

8. Method according to claim 6, wherein said ends are shaped to wave like form and to fit substantially with one another.

9. Method according to claim 7, wherein said tape is applied at said ends by means of said adhesive.

10. Method according to claim 2, wherein said band of material is a polyester cloth.

11. Method according- to -claim 10, wherein said polyester cloth is calendered.

12. Method according to claim 11, wherein said calendered polyester cloth contains a filler.

13. Method according to claim 12, wherein said filler comprises a clay-like substance.

14. Method according to claim 13, wherein said polyester cloth has a surface capable of insuring adhesion to said adhesive.

15. Method according to claim 14, wherein said surface has a phenolic resin coating thereon.

16. Method according to claim 1, wherein said adhesive is a polyurethane adhesive.

17. Method according to claim 14, wherein said polyurethane adhesive is a two part adhesive including a curing agent, said adhesive consisting of BOSTICK 7070TM and said curing agent consisting of BOSKADURTM.

18. Method according to claim 1, wherein said flexible abrasive member is a polyester cloth having a diamond abrasive thereon.

19. Method according to claim 18, wherein said diamond abrasive is nickel plated onto said polyester cloth.

20. Method according to claim 1, wherein said flexible abrasive member comprises a flexible non electrically conductive mesh material, a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having diamond crystals embedded therein.

21. Method according to claim 1, wherein said flexible stretch-free fabric is in the form of a disc, said flexible abrasive member has a shape to conform to said disc and the resulting flexible abrasive member consists of an abrasive disc.

22. Method according to claim 3, which comprises applying a vinyl coating along the edges of said band so as to provide smooth slippery parallel outer edges along said entire band, and selecting a flexible abrasive band to cover only the area of said flexible stretch-free fabric not covered by said vinyl coating.

23. Method according to claim 3, which comprises transversely curving said heat resistant flexible abrasive member to prevent a glass edge to tough extreme outer edges of the belt as the two are moved towards one another, and to enable the glass edge to be abraded as soon as glass enters from the side of the belt.

24. Method of preparing a heat resistant flexible adhesive belt, which comprises: providing a heat-resistant flexible stretch-free band of calendered polyester cloth, said polyester cloth having a phenolic resin coating thereon, applying to said polyester cloth a two part polyurethane adhesive including a curing agent, said adhesive consisting of BOSTICK 7070TM and said curing agent consisting of BOSKA DURIM, laminating onto said polyester cloth an abrasive member comprising a flexible non electrically conductive mesh material, a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having diamond crystals embedded therein, allowing the adhesive to cure and bond both said polyester cloth and said flexible abrasive member, cutting the ends of the belt in wave like form so as to fit substantially with one another, applying some said two part polyurethane adhesive at said wave like ends and joining same to form a joint, applying additional said two part polyurethane adhesive along said joint and placing a MYLARTM or KEVLARTM tape over said joint, and pressing to give a substantially uniform joint.

25. A heat resistant flexible abrasive which comprises a heat-resistant flexible stretch-free fabric and a flexible abrasive member which is laminated onto said fabric by means of an adhesive which is not affected or distorted by heat, solvent or water, does not dry and crack, and retain flexibility when cured.

26. A heat resistant flexible abrasive member according to claim 25, wherein said flexible stretch-free fabric is in the form of a band, said flexible abrasive member has a shape to conform to said band and the resulting flexible abrasive member consists of an abrasive belt.

27. A heat resistant flexible abrasive member according to claim 26, wherein ends of said belt are joined to define a continuous belt.

28. A heat resistant flexible belt according to claim 26, wherein said ends are splicejoined.

29. A heat resistant flexible belt according to claim 28, wherein the splice joint comprises a heat resistant reinforced tape.

30. A heat resistant flexible belt according to claim 29, wherein said tape has a thickness which varies between about 3 and 7 millimeters.

31. A heat resistant flexible belt according to claim 30, wherein said tape is selected from the group consisting of MYLARTM and KEVLARTM.

32. A heat resistant flexible belt according to claim 31, wherein said ends are shaped to wave like form and fit exactly with one another.

33. A heat resistant flexible belt according to claim 31 wherein said bond of material is a polyester cloth.

34. A heat resistant flexible belt according to claim 33, wherein said polyester cloth is calendered.

35. A heat resistant flexible belt according to claim 34, wherein said- calendered polyester cloth contains a filler.

36. A heat resistant flexible belt according to claim 35, wherein said fit rr comprises a clay like substance.

37. A heat resistant flexible belt according to claim 25, wherein said adhesive is a polyurethane adhesive.

38. A heat resistant flexible belt according to claim 37, wherein said polyurethane adhesive is a two part adhesive including a curing agent, said adhesive consisting of BOSTICK 7070TM and said curing agent consisting of BOSKADURTM.

39. A heat resistant flexible belt according to claim 25, wherein said flexible abrasive member is a polyester cloth having a diamond abrasive thereon.

40. A heat resistant flexible belt according to claim 39, wherein said diamond abrasive is nickel plated onto said polyester cloth.

41. A heat resistant flexible belt according to claim 25, wherein said flexible abrasive member comprises a flexible non electrically conductive mesh material, a ayer of electrodeposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having powdered diamond embedded therein.

42. A heat resistant flexible member according to claim 25, wherein said flexible stretch-free fabric is in the form of a disc, said flexible abrasive member has a shape to conform to said disc and the resulting flexible abrasive member consists of a abrasive disc.

43. A heat resistant flexible belt according to claim 27, comprising a vinyl coating along the edges of said band so as to provide smooth slippery parallel outer edges along said entire band, and said flexible abrasive band covering only the area of said flexible stretch-free fabric not covered by said vinyl coating.

44. A heat resistant flexible belt according to claim 27, which is transversely curved to prevent a glass edge to touch extreme outer edges of the belt as the two are moved towards one another, and to enable the glass edge to be abraded as soon as glass enters from the side of the belt.

45. A heat resistant flexible adhesive belt, which comprises: a heat resistant flexible stretch-free band of calendered polyester cloth, said polyester cloth having a phenolic resin coating thereon, and an abrasive member which is laminated onto said polyester cloth, by means of a poly urethane adhesive including a curing agent, said adhesive consisting of BOSTICK 7070TM and said curing agent consisting of BOSKA DURTM, said abrasive member comprising a flexible non electrically conductive mesh material, a layer of electro-deposited nickel adhered directly to and extending through the mesh material, so that the mesh material is embedded in the nickel layer, the layer of nickel having powdered diamond embedded therein, the ends of the belt being in wave like form so as to fit substantially with one another, and being joined together by means of some said two part polyurethane adhesive at said wave like ends, said wave like form ends being additionally spliced together by means of additional said two part polyurethane adhesive, and a MYLARTM or KEVLARTM tape over said joint.