Thixotropic grease composition

US4810395A · kind A · utility

Assignee

• American Telephone and Telegraph Company, AT&T Bell Laboratories · US

Inventors

• Alvin C. Levy · Atlanta, US
• Bob J. Overton · Lenoir, US

Key dates

• Filing date: May 20, 1987
• Grant date: Mar 7, 1989
• Expiry date: May 20, 2007

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/4401
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A grease composition comprising oil, colloidal particle filler, and, optionally, a bleed inhibitor is disclosed. The grease typically has a critical yield stress below 140 Pa at 20.degree. C., preferably below 70 or 35 Pa. The grease can advantageously be used as a cable filling material, especially for optical fiber cable. In the latter case it can result in cable having substantially no cabling loss. Preferred compositions comprise 77 to 95% b.w. of ASTM type 103, 104 A, or 104B paraffinic or naphthenic oil, or polybutene oil; 2 to 15% b.w. of hydrophobic or hydrophilic fused silica; and optionally, up to 15% b.w. of styrene-rubber or styrene-rubber-styrene block copolymer, or semiliquid rubber.