Method of protecting surfaces of glass substrates

US6491972B1 · kind B1 · utility

Assignee

• Schott Glas · DE

Inventors

• Andreas Weber · Salzburg, AT
• Reiner Mauch · Guldental, DE
• Roland Buerkle · Nieder-Olm, DE
• Andreas Berndt · Oldenburg, DE
• Dirk Schlatterbeck · Friltschen, CH
• Marten Walther · Engelstadt, DE

Key dates

• Filing date: Feb 15, 2000
• Grant date: Dec 10, 2002
• Expiry date: Feb 15, 2020

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31649
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A method of protecting a surface of a display glass or a hard disk substrate during processing arid transport includes applying at least one polyvinyl alcohol or other polymer protective layer on the surface, which is soluble in polarorganic solvents, so that the layer can be removed after processing and transport by washing in heated water or a polar organic solvent without leaving residues on the surface. The polyvinyl alcohol used to make the protective coating has an average molecular weight of ≧ about 60,000 g/mol and a hydrolysis degree of ≧95% and the at least one polyvinyl alcohol layer is dried by heating at temperatures of about 150° C. or less to form the protective coating after applying the polyvinyl alcohol layer. The other polymers are less soluble in water than polyvinyl alcohol but are easily removed with organic solvent.