High strength ceramic fiber board

• US 5,273,821 A
• Filed: 11/12/1991
• Issued: 12/28/1993
• Est. Priority Date: 11/12/1991
• Status: Expired due to Term

• Current Assignee: Unifrax I LLC (ASP Unifrax Holdings, Inc.)
• Original Assignee: Carborundum Universal Investment Limited (Compagnie de Saint-Gobain SA)
• Inventors: Stahlman, Mark D., Olson, James R.
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): EDWARDS, NEWTON O
• Application Number:
  US07/790,938
• Time in Patent Office: 777 Days
• Field of Search: 428/357, 428/384, 428/379, 501/95, 162/152, 162/150, 162/145, 162/175, 524/47, 524/52, 524/53
• US Class Current: 428/357
• CPC Class Codes: C04B 14/4625 Alumina
• CPC Class Codes: C04B 14/4656 Al-silicates, e.g. clay
• CPC Class Codes: C04B 16/0641 Polyvinylalcohols; Polyvinylacetates
• CPC Class Codes: C04B 2235/5212 Organic
• CPC Class Codes: C04B 2235/5224 Alumina or aluminates
• CPC Class Codes: C04B 2235/5228 Silica and alumina, including aluminosilicates, e.g. mullite
• CPC Class Codes: C04B 2235/606 Drying
• CPC Class Codes: C04B 2235/608 Green bodies or pre-forms with well-defined density
• CPC Class Codes: C04B 2235/61 Mechanical properties, e.g. fracture toughness, hardness, Young's modulus or strength
• CPC Class Codes: C04B 24/38 Polysaccharides or derivatives thereof C04B24/243 takes precedence
• CPC Class Codes: C04B 24/383 Cellulose or derivatives thereof
• CPC Class Codes: C04B 28/14 containing calcium sulfate cements gypsum-paper plates E04C
• CPC Class Codes: C04B 28/24 containing alkyl, ammonium or metal silicates; containing silica sols reaction mixtures resulting in mineral polymers C04B28/006; polymeric reaction products of alkali metal silicates with isocyanates C08G18/3895
• CPC Class Codes: C04B 33/36 Reinforced clay-wares
• CPC Class Codes: C04B 35/14 based on silica
• CPC Class Codes: C04B 35/6263 characterised by their solids loadings, i.e. the percentage of solids
• CPC Class Codes: C04B 35/6316 Binders based on silicon compounds
• CPC Class Codes: C04B 35/636 Polysaccharides or derivatives thereof
• CPC Class Codes: C04B 35/80 Fibres, filaments, whiskers, platelets, or the like
• CPC Class Codes: Y10T 428/29 Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
• CPC Class Codes: Y10T 428/2949 : Glass, ceramic or metal oxide in coating

Abstract

A high strength ceramic fiber board having a green strength of at least 300 psi and a green density of less than about 22 lb/ft³ ; and having a composition comprising 65-97.5% wt. ceramic fiber, 1-10% wt. PVA fiber, 0.5-10% wt. cationic starch, 0-25% wt. clay filler and 1.0-15% wt. colloidal silica.

Claims

1. A high strength ceramic fiber board having a green strength of at least 300 psi and a green density less than about 22 lb/ft³ formed from a composition comprising 65-97.5% wt. ceramic fiber, 1-10% wt. PVA fiber, 0.5-10% wt. cationic starch, 0-25% wt. clay filler and 1.0-15% wt. colloidal silica.

2. A high strength ceramic fiber board as in claim 1 wherein said ceramic fiber is selected from the group consisting of non-crystalline aluminosilicate fibers, crystalline high alumina fibers, and mixtures thereof.

3. A high strength ceramic fiber board as in claim 1 wherein said cationic starch is selected from the group consisting of potato starch and corn starch.

4. A high strength ceramic fiber board as in claim 2 wherein the average diameter of said ceramic fiber is in the range of about 1-4 microns.

5. A high strength ceramic fiber board as in claim 1 wherein the composition comprises about 90% wt. ceramic fiber, about 5% wt. PVA fiber, about 1.5% wt. cationic starch and about 3.5% wt. colloidal silica.

6. A high strength ceramic fiber board as in claim 1 wherein said green strength is about 350 psi and said green density is about 18 lb/ft³.

7. A high strength ceramic fiber board as in claim 1 wherein said green strength is about 500 psi and said green density is about 21.5 lb/ft³.

8. A high strength ceramic fiber board as in claim 1 wherein the composition comprises about 79% wt. ceramic fiber, about 5% wt. PVA fiber, about 2.0% wt. cationic starch, about 10% wt. clay filler and about 4.0% wt. colloidal silica.

9. A high strength ceramic fiber board having a green strength of at least 300 psi and a green density less than about 30 lb/ft³, and wherein said ceramic fiber board is machinable without significant breakage.