Method of manufacturing polishing pad

• US 10,457,790 B2
• Filed: 04/06/2016
• Issued: 10/29/2019
• Est. Priority Date: 04/06/2016
• Status: Active Grant

• Current Assignee: KPX Chemical Co., Ltd.
• Original Assignee: KPX Chemical Co., Ltd.
• Inventors: Kim, Seung-Geun, Kang, Hak-Su, Choo, Jeong-Seon, Jung, Dae-Han, Park, Gi-Young
• Primary Examiner(s): Daniels, Matthew J
• Assistant Examiner(s): Swier, Wayne K.
• Application Number:
  US15/534,828
• Publication Number:
  US 20180118908A1
• Time in Patent Office: 1,301 Days
• CPC Class Codes: B24B 37/24 characterised by the composition or properties of the pad materials
• CPC Class Codes: B29C 44/3415 Heating or cooling
• CPC Class Codes: B29C 44/3442 Mixing, kneading or conveying the foamable material mixing plastics B29B7/00; mixing in general B01F
• CPC Class Codes: B29C 44/56 After-treatment of articles, e.g. for altering the shape
• CPC Class Codes: B29C 44/5627 by mechanical deformation, e.g. crushing, embossing, stretching
• CPC Class Codes: B29C 69/001 a shaping technique combined with cutting, e.g. in parts or slices combined with rearranging and joining the cut parts for reinforced material B29C70/545; B29C49/4278, B29C51/268 take precedence
• CPC Class Codes: B29K 2075/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/0061 Gel or sol
• CPC Class Codes: B29K 2105/24 crosslinked or vulcanised
• CPC Class Codes: B29L 2031/736 Grinding or polishing equipment
• CPC Class Codes: C08G 18/12 using two or more compounds having active hydrogen in the first polymerisation step
• CPC Class Codes: C08G 18/3808 having chlorine atoms
• CPC Class Codes: C08G 18/4804 Two or more polyethers of different physical or chemical nature
• CPC Class Codes: C08G 18/4808 Mixtures of two or more polyetherdiols
• CPC Class Codes: C08G 18/4825 Polyethers containing two hydroxy groups C08G18/4833 - C08G18/5096 take precedence
• CPC Class Codes: C08G 18/4854 Polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
• CPC Class Codes: C08G 18/4858 Polyethers containing oxyalkylene groups having more than four carbon atoms in the alkylene group
• CPC Class Codes: C08G 18/7621 being toluene diisocyanate including isomer mixtures
• CPC Class Codes: C08J 2203/06 CO2, N2 or noble gases
• CPC Class Codes: C08J 2203/182 of physical blowing agents, e.g. acetone and butane
• CPC Class Codes: C08J 2207/00 : Foams characterised by their intended use
• CPC Class Codes: C08J 2375/08 : from polyethers
• CPC Class Codes: C08J 9/06 : by a chemical blowing agent
• CPC Class Codes: C08J 9/122 : Hydrogen, oxygen, CO2, nitrogen or noble gases
• CPC Class Codes: C08J 9/127 : Mixtures of organic and inorganic blowing agents
• CPC Class Codes: C08J 9/14 : organic

Abstract

A method of manufacturing a polishing pad includes producing an urethane prepolymer having a viscosity of 20,000 cps (at 25° C.) to 40,000 cps (at 25° C.) by mixing a plurality of polymers, mixing the urethane prepolymer with an inert gas and a low-boiling blowing agent having a boiling point of 60° C. to 150° C., and manufacturing a polishing layer including porous pores by causing a mixture produced at the mixing to be subjected to gelation and curing in a predetermined cast.

Claims

1. A method of manufacturing a polishing pad, the method comprising:

(a) producing an urethane prepolymer having a viscosity of 20,000 cps (at 25°

C.) to 40,000 cps (at 25°

C.) by mixing a plurality of polymer molecules, wherein the plurality of polymer molecules comprises a polymer having four or more hydroxyl groups, and an amount of the polymer having four or more hydroxyl groups ranges from 1% to 30% based on a total weight of the urethane prepolymer;

(b) mixing the urethane prepolymer produced at the producing step (a) with an inert gas and a low-boiling blowing agent having a boiling point of 60°

C. to 150°

C.; and

(c) manufacturing a polishing layer including porous pores by causing a mixture produced at the mixing step (b) to be subjected to gelation and curing in a predetermined cast,

wherein, the mixing step (b) includes causing an average size of pores produced by mixing the inert gas of 5% to 30% and the low-boiling blowing agent of 0.1% to 10% of a total volume of a mixture produced at the mixing step (b) with the urethane prepolymer produced at the producing step (a) to be 31 μ

m or smaller.

2. The method according to claim 1, wherein,

the manufacturing step (c) includes manufacturing the polishing layer with a generation of a glazing phenomenon suppressed by forming a polyurethane having a three-dimensional bonding structure by mixing the urethane prepolymer produced at the producing step (a) and a curing agent.

3. The method according to claim 2, wherein, the plurality of polymer molecules includes any one selected from the group consisting of polypropylene glycol, polyurethane, polyether, polyester, polysulfone, polyacrylic, polycarbonate, polyethylene, polymethyl methacrylate, polyvinyl acetate, polyvinyl chloride, polyethyleneimine, polyethersulfone, polyetherimides, polyketone, melamine, nylon, fluorohydrocarbon, and any combination thereof.

4. The method according to claim 1, further comprising opening the porous pores on a surface of the polishing layer by processing the polishing layer.

5. The method according to claim 1, wherein the polymer having four or more hydroxyl groups is a polypropylene glycol having four or more hydroxyl groups.

6. The method according to claim 5, wherein the plurality of polymer molecules further comprises toluene disocyanate and polytetramethylene glycol.