Photocatalytically-activated self-cleaning article and method of making same

In a method for forming a glass float ribbon wherein the method includes the steps of melting glass batch materials in a furnace;

• delivering the molten glass onto a bath of molten tin;
• pulling the molten glass across the tin bath whereupon the glass is sized and controllably cooled to form a dimensionally stable glass float ribbon;
• removing the float ribbon from the tin bath;
• moving the float ribbon by conveying roller through a lehr to anneal the float ribbon;
• moving the float ribbon to a cutting station on conveying rollers where the ribbon is cut into glass sheets, the improvement comprising:
• depositing by a process selected from the group consisting of spray pyrolysis and chemical vapor deposition a crystalline phase of a photocatalytically-activated self-cleaning coating over a surface of said float ribbon as the float ribbon is formed, whereby said coating has a photocatalytically-activated self-cleaning reaction rate of at least about 2.times.10.sup.-3 cm.sup.-1 min.sup.-1.

A method comprising the steps of:

• providing an article of manufacture having at least one surface;
• depositing a sodium ion diffusion barrier layer by a process selected from the group consisting of chemical vapor deposition, magnetron sputtered vacuum deposition (MSVD), and spray pyrolysis having a thickness of at least 100 .ANG. over said surface;
• and
• depositing a photocatalytically-activated self-cleaning coating by a process selected from the group consisting of chemical vapor deposition, MSVD, and spray pyrolysis over said sodium ion diffusion barrier layer whereupon said sodium ion diffusion barrier layer inhibits migration of sodium ions from the surface of said article to said photocatalytically-activated self-cleaning coating.

In a method for forming a glass float ribbon wherein the method includes the steps of melting glass batch materials in a furnace;

• delivering the molten glass onto a bath of molten tin;
• pulling the molten glass across the tin bath whereupon the glass is sized and controllably cooled to form a dimensionally stable glass float ribbon;
• removing the float ribbon from the tin bath;
• moving the float ribbon by conveying roller through a lehr to anneal the float ribbon;
• moving the float ribbon to a cutting station on conveying rollers where the ribbon is cut into glass sheets, the improvement comprising:
• depositing as the float ribbon is formed a photocatalytically-activated self-cleaning coating over said float ribbon which has a major surface and an opposing other major surface, wherein the major surface which contacted the tin bath has tin diffused therein so that the deposition is on the major surface having the diffused tin which forms a sodium ion barrier layer for the photocatalytically-activated self-cleaning coating.