Process for making urea-formaldehyde insulation
AssigneeCiba-Geigy Corporation
InventorsCharles E. Elmore, David H. Harmon
Life of this patent
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Abstract
A process and apparatus are provided for making desired shapes of urea-formaldehyde suitable for use as insulation from urea-formaldehyde foam. Fluid urea-formaldehyde foam (A) is formed into discrete particles (A') in particle generator (10) which also partially cures particles (A'). After particles (A') are fully cured, they are blended with fluid urea-formaldehyde foam in mixing apparatus (11) which includes blending head (66) to produce mixture (C) which is a coherent mass. Mixture (C) is molded to the desired cross-sectional shape by molding conveyor (12). Cutter (132) cuts formed mixture (C) into the desired length. Thereafter oven (146) is utilized for fully curing the product which is then enclosed in a suitable packaging material.
Claims12
A method of producing cured urea-formaldehyde foam in desired shapes from urea-formaldehyde foam comprising:
- (a) forming discrete urea-formaldehyde particles from the urea-formaldehyde foam such that the discrete urea-formaldehyde particles, when cured, are between about one-half and six inches in length and between about one-quarter and one inch in cross-sectional dimension;
- (b) curing said discrete urea-formaldehyde particles;
- (c) mixing said cured particles with uncured urea-formaldehyde foam to form a resulting mixture that is a coherent mass, wherein said resulting mixture contains said uncured foam and cured particles in a volume ratio of uncured foam to cured particles of between about 1:1 and 1:4;
- (d) forming said resulting mixture into the desired shape;
- and thereafter
- (e) curing the uncured urea-formaldehyde foam present in said mixture to provide a cured mass of urea-formaldehyde of the desired shape.
A method for producing cured urea-formaldehyde foam into desired shapes from cured particles of urea-formaldehyde foam comprising:
- (a) mixing fluid urea-formaldehyde foam with cured particles that are between about one-half and six inches in length and between about one-quarter and one inch in cross-sectional dimension to form a resulting mixture that is a coherent mass, wherein said resulting mixture contains said uncured foam and cured particles in a volume ratio of uncured foam to cured particles of between about 1:1 and 1:4;
- (b) forming said resulting mixture into the desired shape;
- and thereafter
- (c) curing said resulting mixture.
Dependencies are inferred from the claim text.