EP0366051A1 - Coussin produisant un gel nouveau et procédé pour surfacer et polir des lentilles - Google Patents

Coussin produisant un gel nouveau et procédé pour surfacer et polir des lentilles Download PDF

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Publication number
EP0366051A1
EP0366051A1 EP89119666A EP89119666A EP0366051A1 EP 0366051 A1 EP0366051 A1 EP 0366051A1 EP 89119666 A EP89119666 A EP 89119666A EP 89119666 A EP89119666 A EP 89119666A EP 0366051 A1 EP0366051 A1 EP 0366051A1
Authority
EP
European Patent Office
Prior art keywords
pad
substrate
surfacing
liquid
abrasive
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP89119666A
Other languages
German (de)
English (en)
Other versions
EP0366051B1 (fr
Inventor
Mark M. Mayton
Alan J. Lopresti
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vibrantz Corp
Original Assignee
Ferro Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ferro Corp filed Critical Ferro Corp
Publication of EP0366051A1 publication Critical patent/EP0366051A1/fr
Application granted granted Critical
Publication of EP0366051B1 publication Critical patent/EP0366051B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/001Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as supporting member
    • B24D3/002Flexible supporting members, e.g. paper, woven, plastic materials
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B13/00Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor
    • B24B13/01Specific tools, e.g. bowl-like; Production, dressing or fastening of these tools
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/02Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent
    • B24D3/20Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially organic

Definitions

  • This invention relates to an improved method and product for surfacing and/or polishing lenses and the like. More particularly, this invention relates to a novel gel producing fining or polishing pad which considerably simplifies the process of fining and/or polishing lenses.
  • the process for producing fine ground or polished surfaces on optical materials is much the same regardless of the type of fining or polishing medium employed, or the type of material being processed.
  • a fining or polishing pad is moved across the surface of the material to be processed, while either a slurry containing abrasive particles, or plain water, is directed in a stream between the pad and the surface to be processed.
  • U.S. patent No. 4,255,164 discloses a glass fining pad or sheet having a water insoluble, microcellular matrix containing abrasive fining particles. When the pad is used with an aqueous flow or stream its matrix breaks down and allegedly releases the fining particles at a controlled rate. While being effective for the grinding or fining stages of surfacing, this type of pad is not effective for polishing, even when using a polishing grade abrasive.
  • U.S. patent No. 4,576,612 discloses a polishing pad having a water soluble matrix containing polishing particles. A stream of water which is directed onto the interface between the pad and the work causes the exposed surface of the matrix slowly to dissolve thus slowly releasing polishing particles.
  • U.S. patent No. 3,042,509 also discloses a wax-like, polyethylene based polishing compound containing polishing particles, and adapted to be rubbed onto the surface of a buffing wheel or lap to provide both lubricating and polishing properties for the wheel or lap surface.
  • the compound is water-soluble so that it can be washed off of the wheel after the buffing operation.
  • One object of this invention is to provide an improved fining or polishing process which eliminates the need for directing a stream of water or liquid slurry onto the work, thereby circumventing many of the problems associated with the previously mentioned process.
  • Still another object is to provide a novel water absorbent or adsorbent pad which, when wetted, makes all of its brasive material instantly available for fining or polishing.
  • a further object of this invention is to provide a novel pad of the type described having an abrasive-containing matrix made from a polymer which can absorb and retain large amounts of water to enable formation of a long lasting gel.
  • the hereinafter described pad provides a disposable, self-contained article for fining or polishing the surfaces of various materials (plastics, metals, glass, ceramics, etc.) using only a small amount of a liquid agent to produce between the pad and the work a gel which contains abrasive particles (fining or polishing).
  • the abrasive particles (aluminum oxide, cerium oxide, etc.) are dispersed in a water absorbent or adsorbent, gel-producing carrier or matrix, which is coated uniformly onto a flexible reinforcing substrate, such as for example a fabric of the type used for conventional polishing or finishing pads.
  • An adhesive is applied to the back of the substrate, and the entire structure is cut to form a conventionally shaped, multi-petal pad.
  • the pad is attached to a surfacing lap and its matrix and substrate are wetted with a small amount of liquid. The motion of the lap forms on the pad a gel, which acts like a viscous slurry to surface the associated workpiece
  • the optimum abrasive carrier or matrix provides rapid gelation, uniform dispersion of surfacing agent, lubrication between the lap or other surfacing substrate and the object being fined or polished, and produces a viscous matrix which retains or prevents loss of the abrasive.
  • the preferred, matrix-supporting substrate is a fabric capable of absorbing water to function as a reservoir for the gel produced during use. The replacement of a slurry with a gel producing matrix eliminates the need for preparing, storing, and disposing of liquid slurries. It also reduces machine maintenance and cleanup-time.
  • 10 denotes generally a gel producing surfacing pad having therein the usual radial slots 11, which lend to the pad the conventional appearance of a petal-shaped pad.
  • Pad 10 comprises several parts, each of which is responsible for a distinct function.
  • 12 denotes the attachment layer - which, as noted hereinafter is used to attach the pad 10 to a lap or the like.
  • This layer 12 may be any adhesive well known to the industry, such as for example a PSA adhesive.
  • Numeral 14 denotes the substrate layer.
  • This layer has several functions. It provides an intermediate supporting layer between the attachment layer 12 and the hereinafter described surfacing layer; it provides a pliable surface which keeps the hereinafter described abrasive particles in contact with the surface which is being polished or fined; it retains a small amount of abrasive particles in its structure; and in use it acts a a reservoir for the wettnig liquid.
  • Any number of synthetic or natural pliable sheet materials can be used for the substrate layer 14, including but not limited to cotton, felt, paper, and woven or non-woven synthetics. These materials can be a flocked form, or may be altered in other ways (perforated, embossed, etc.) to help them retain abrasive particles and the surfacing layer or particle carrier layer.
  • the surfacing or particle carrier layer is denoted at 15, and comprises, preferably, a water absorbent matrix 16 containing abrasive particles 17.
  • Layer 15 is the key component of the gel producing abrasive pad, and as noted hereinafter usually is coated as a paste onto substrate 14 in the range of approximately 10 milligrams to more than 250 milligrams of paste per square centimeter of the substrate surface. When applied in this manner, part of the matrix 16 and its particles 17 penetrate to a certain extent into the fabric substrate (Fig. 2), particularly in those cases where layer 14 is flocked or felted. Layer 15 has multiple functions which should be balanced to produce a good quality surface in the shortest amount of time.
  • the abrasive particles 17 preferably have a Knoop hardness of greater than 1000, and are of a particle size distribution which allows for rapid stock removal with the least amount of scratches left on the surface.
  • the particles 17 preferably should have an average particle size of 0.1 to 10.0 micrometers or microns, and for fining pads a range of from 10.0 to 50.0 micrometers is recommended.
  • Abrasives that can be used include, but are not limited to, cerium oxide, aluminum oxide, silica, etc.
  • the gelling agent or matrix 16 which forms a gel on contact with a liquid, provides a medium which holds the abrasive particles 17 in the presence of a liquid between the substrate 14 and the material being surfaced (not illustrated).
  • the matrix 16 is capable of holding relatively large amounts of liquid, which takes on swarf from the abraded surface, provides lubrication between the pad and the object being surfaced, and can provide cooling to materials which are heat sensitive.
  • Materials suitable for creating matrix 16 include cellulose based materials, clays, alumina-silicates, polymer silicas, and similar materials.
  • Other additives can be used in conjunction with the gelling agent to matrix 16, such as chemical polishing accelerators, coolants, oxidation inhibitors, etc.
  • Part B was then mixed into Part A until the mixture was a smooth paste.
  • Ratio of abrasive (150 gr.) to dry carrier (10 gr.) was 15:1.
  • the mixture of parts A and B was then coated as a layer 15 onto a pad substrate 14 which comprised of a commercially available flocked polyester fabric such as 0.020 inch rayon flock sold by Tempo/Shane of Peabody Mass.
  • a pad substrate 14 which comprised of a commercially available flocked polyester fabric such as 0.020 inch rayon flock sold by Tempo/Shane of Peabody Mass.
  • the layer 15 of paste was coated on substrate 14 to a thickness of approximately .005 - .008 inches.
  • the fabric substrate 14 was then placed in an oven at 300 o F. for five minutes. After cooling the fabric, a pressure sensitive adhesive layer 12 was attached to the back of layer 14, and pad 10 was cut to its desired shape using a steel rule die.
  • Each of a first set of polishing pads made according to Example No. 1 was mounted on a lap 20 and saturated with about 20 ml. of water, enough to wet the matrix 16 and to saturate the reservoir layer or substrate 14.
  • the lap was put on a Coburn 505 polishing machine set on low speed and at a pressure of at 20 psi.
  • a fined plastic lens (Supremacy 65 form Coburn Optical Industries, Muskogee, OK.) was mounted and (polished) run for three minutes for each pad.
  • a second set of pads was prepared and run using the same procedure, except that in preparing part A of Example No. 1, the amount of propylene glycol was increased to 40 grams, and each pad was not saturated with water.
  • a third set of pads was prepared and run using the same gel/abrasive matrix and polyester fabric as in the first set, but the uncoated pad fabric was first attached to the lap, after which 4 grams of paste was smeared onto each pad.
  • Fine-Rite .025 Alumina produced by Ferro Corp., Penn Yan, N.Y., plus 100 grams of deionized water, and 5 grams of Darvan 7, all of which were mixed until well dispersed.
  • CMC 7L carboxymethylcellulose
  • propylene glycol 15 grams were mixed until well dispersed. Part B was then mixed into Part A under agitation. Ratio of abrasive (150 gr.) to dry carrier (15 gr.) was 10:1.
  • This mixture was coated as a layer 15 onto a .005 inch glass- polishing fabric substrate, which was the type sold by Pellon of Chelmsford, Ma., at thickness of .005 inches, and placed in a 300 o F. oven until dry.
  • the cooled material was laminated to a pressure sensitive adhesive layer 17 and a multi-petal pad was die-cut from this material.
  • the fining pad of Example No. 2 was mounted on a lap 20 and saturated with about 20 milliliters of water.
  • the lap was put on a Coburn 505 polishing machine set on low speed at a pressure of 20 psi.
  • a plastic lens was mounted and run (fined) for two minutes by the pad of Example No. 2.
  • the paste was coated on a flocked polyester pad or substrate 14, which was then attached to a polishing lap.
  • the lap was attached to a Coburn 505 polishing machine and run for three minutes on low speed at a pressure of 20 psi.
  • a plastic lens was used.
  • gel is intended to have its common meaning such as for example of substance which is a colloid in which the disbursed phase was combined with the continuous phase to produce a semisolid material, such as a jelly.
  • the present invention considerably simplifies the process and apparatus heretofore required to fine grind and/or to polish rigid surfaces, such as for example the surfaces of optical lenses.
  • a special gel-producing pad it is possible to eliminate the need for directing a stream of liquid slurry or water onto the interface between a pad and lens, for example, thus eliminating also the need for using recirculating pumps and/or filters for directing a slurry continuously onto the work during a surfacing operation.
  • the novel pad disclosed herein it is necessary only to wet the surface of the pad at the commencement of a surfacing operation, and possibly to squirt a supplemental amount of liquid onto the pad during prolonged surfacing operations.
  • the ratio of abrasive to dry carrier be kept as high as possible.
  • pads of the type disclosed herein can be utilized to surface rigid products or work pieces other than optical lenses, for example in the lapidary and gem making art.
  • other organic compounds could be used as gel producing matrices, such as for example polyvinyl alcohol, polyethelene glycol, alginates, gums, and combinations thereof, they are not quite as effective as the above-noted water absorbing or retaining materials such as cellulose based materials and the like.
  • fabric substrates such as denoted at 14, other flexible, water absorbing and retaining substrates could be employed without departing from this invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
  • Grinding And Polishing Of Tertiary Curved Surfaces And Surfaces With Complex Shapes (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
EP19890119666 1988-10-26 1989-10-24 Coussin produisant un gel nouveau et procédé pour surfacer et polir des lentilles Expired - Lifetime EP0366051B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US26283888A 1988-10-26 1988-10-26
US262838 1988-10-26

Publications (2)

Publication Number Publication Date
EP0366051A1 true EP0366051A1 (fr) 1990-05-02
EP0366051B1 EP0366051B1 (fr) 1993-03-10

Family

ID=22999282

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890119666 Expired - Lifetime EP0366051B1 (fr) 1988-10-26 1989-10-24 Coussin produisant un gel nouveau et procédé pour surfacer et polir des lentilles

Country Status (5)

Country Link
EP (1) EP0366051B1 (fr)
JP (1) JP2796678B2 (fr)
CA (1) CA2001487C (fr)
DE (1) DE68905297T2 (fr)
MX (1) MX171378B (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0438671A2 (fr) * 1990-01-22 1991-07-31 Somar Corporation Ruban abrasif et sa méthode de fabrication
WO1994013434A1 (fr) * 1992-12-17 1994-06-23 Minnesota Mining And Manufacturing Company Suspensions epaisses a viscosite reduite, articles abrasifs fabriques a partir de ces suspensions et procedes de fabrication des articles
WO2001083163A2 (fr) * 2000-04-28 2001-11-08 3M Innovative Properties Company Procede de nettoyage de verre
US6638144B2 (en) 2000-04-28 2003-10-28 3M Innovative Properties Company Method of cleaning glass
US7503834B2 (en) 2004-01-15 2009-03-17 Carl Zeiss Vision Gmbh Apparatus and a method of polishing an optical surface; an optical component; and a method of manufacturing a polishing tool
WO2022237200A1 (fr) * 2021-05-12 2022-11-17 华侨大学 Procédé de préparation d'un bloc à polir sol-gel souple

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH069869U (ja) * 1992-05-19 1994-02-08 裕一 市口 研磨具
JP2595909Y2 (ja) * 1992-08-24 1999-06-02 ホーヤ株式会社 レンズ研磨用パッド

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4255164A (en) * 1979-04-30 1981-03-10 Minnesota Mining And Manufacturing Company Fining sheet and method of making and using the same
US4576612A (en) * 1984-06-01 1986-03-18 Ferro Corporation Fixed ophthalmic lens polishing pad
EP0192047A2 (fr) * 1985-02-22 1986-08-27 International Business Machines Corporation Article abrasif fixé à base de Polyuréthane
EP0211591A2 (fr) * 1985-08-07 1987-02-25 Minnesota Mining And Manufacturing Company Agglomérats érodables et abrasifs les contenantainsi que la méthode de préparation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4255164A (en) * 1979-04-30 1981-03-10 Minnesota Mining And Manufacturing Company Fining sheet and method of making and using the same
US4576612A (en) * 1984-06-01 1986-03-18 Ferro Corporation Fixed ophthalmic lens polishing pad
EP0192047A2 (fr) * 1985-02-22 1986-08-27 International Business Machines Corporation Article abrasif fixé à base de Polyuréthane
EP0211591A2 (fr) * 1985-08-07 1987-02-25 Minnesota Mining And Manufacturing Company Agglomérats érodables et abrasifs les contenantainsi que la méthode de préparation

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0438671B1 (fr) * 1990-01-22 1996-07-10 Somar Corporation Ruban abrasif et sa méthode de fabrication
EP0438671A2 (fr) * 1990-01-22 1991-07-31 Somar Corporation Ruban abrasif et sa méthode de fabrication
USRE35709E (en) * 1992-12-17 1998-01-06 Minnesota Mining And Manufacturing Corporation Reduced viscosity slurries, abrasive articles made therefrom and methods of making said articles
US5470368A (en) * 1992-12-17 1995-11-28 Minnesota Mining And Manufacturing Company Reduced viscosity slurries, abrasive articles made therefrom, and methods of making said articles
US5496387A (en) * 1992-12-17 1996-03-05 Minnesota Mining And Manufacturing Company Binder precursor dispersion method of making abrasive articles made from reduced viscosity slurries, and method of reducing sedimentation rate of mineral particles
US5368619A (en) * 1992-12-17 1994-11-29 Minnesota Mining And Manufacturing Company Reduced viscosity slurries, abrasive articles made therefrom and methods of making said articles
WO1994013434A1 (fr) * 1992-12-17 1994-06-23 Minnesota Mining And Manufacturing Company Suspensions epaisses a viscosite reduite, articles abrasifs fabriques a partir de ces suspensions et procedes de fabrication des articles
WO2001083163A2 (fr) * 2000-04-28 2001-11-08 3M Innovative Properties Company Procede de nettoyage de verre
WO2001083163A3 (fr) * 2000-04-28 2002-03-28 3M Innovative Properties Co Procede de nettoyage de verre
US6638144B2 (en) 2000-04-28 2003-10-28 3M Innovative Properties Company Method of cleaning glass
KR100750759B1 (ko) * 2000-04-28 2007-08-20 쓰리엠 이노베이티브 프로퍼티즈 캄파니 유리 세척 방법
US7503834B2 (en) 2004-01-15 2009-03-17 Carl Zeiss Vision Gmbh Apparatus and a method of polishing an optical surface; an optical component; and a method of manufacturing a polishing tool
EP1711311B2 (fr) 2004-01-15 2011-07-20 Carl Zeiss Vision GmbH Dispositif et procede pour polir une surface optique et procede pour realiser un outil de polissage
WO2022237200A1 (fr) * 2021-05-12 2022-11-17 华侨大学 Procédé de préparation d'un bloc à polir sol-gel souple

Also Published As

Publication number Publication date
JP2796678B2 (ja) 1998-09-10
CA2001487A1 (fr) 1990-04-26
JPH02167662A (ja) 1990-06-28
CA2001487C (fr) 1994-03-22
EP0366051B1 (fr) 1993-03-10
DE68905297T2 (de) 1993-06-17
MX171378B (es) 1993-10-21
DE68905297D1 (de) 1993-04-15

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