Method for manufacturing polishing pad
View Patent ↗A method for manufacturing a polishing pad, which may be laminated, with a small number of manufacturing steps, high productivity and no peeling between a polishing layer and a cushion layer includes preparing a cell-dispersed urethane composition by a mechanical foaming method; continuously discharging the cell-dispersed urethane composition onto a face material, while feeding the face material; laminating another face material on the cell-dispersed urethane composition; curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a polishing layer including a polyurethane foam is formed; cutting the polishing layer parallel to the face into two pieces so that two long polishing layers each including the polishing layer and the face material are simultaneously formed; and cutting the long polishing layers to produce the polishing pad.
1. A method for manufacturing a polishing pad, comprising the steps of:
preparing a cell-dispersed urethane composition by a mechanical foaming method;
continuously or intermittently discharging a light transmitting region-forming material onto a prescribed site of a face material, while feeding the face material;
continuously discharging said cell-dispersed urethane composition onto a part of said face material where the light transmitting region-forming material is not provided;
laminating another face material on said discharged light transmitting region-forming material and cell-dispersed urethane composition;
curing the light transmitting region-forming material and the cell-dispersed urethane composition, while controlling their thickness to be uniform, so that a long polishing layer comprising a light transmitting region and a polishing region integrated therewith is formed; and
cutting the long polishing layer.
2. The method according to claim 1 , wherein said light transmitting region-forming material has a viscosity of 1 to 30 Pa·s when discharged.
3. The method according to claim 1 , wherein said cell-dispersed urethane composition has a viscosity of 1 to 20 Pa·s when discharged.
4. The method according to claim 1 , wherein said light transmitting region comprises a thermosetting resin.
5. The method according to claim 4 , wherein said thermosetting resin is a polyurethane resin.
6. A method for manufacturing a laminated polishing pad, comprising the steps of:
preparing a cell-dispersed urethane composition by a mechanical foaming method;
discharging a light transmitting region-forming material such that the material is deposited in and on through holes, while feeding a cushion layer having continuously or intermittently provided through holes;
continuously discharging said cell-dispersed urethane composition onto a part of said cushion layer where the light transmitting region-forming material is not provided;
laminating a face material on the discharged light transmitting region-forming material and cell-dispersed urethane composition;
curing the light transmitting region-forming material and the cell-dispersed urethane composition, while controlling their thickness to be uniform, so that a long laminated sheet comprising a light transmitting region and a polishing region integrated therewith is formed; and
cutting the long laminated sheet.
7. The method according to claim 6 , wherein said light transmitting region-forming material has a viscosity of 1 to 30 Pa·s when discharged.
8. The method according to claim 6 , wherein said cell-dispersed urethane composition has a viscosity of 1 to 20 Pa·s when discharged.
9. The method according to claim 6 , wherein said light transmitting region comprises a thermosetting resin.
10. The method according to claim 9 , wherein said thermosetting resin is a polyurethane resin.