# US 4,400,433 A · Process for the preparation of molding flexible graphite granules and a molded graphite product produced therefrom

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- Number: US 4,400,433 A
- Document ID: US4400433A
- Status: Granted
- Kind: A
- Application number: 06/260,172
- Filed: 1981-05-04
- Granted: 1983-08-23
- Earliest claimed: 1980-05-02
- Assignees: Fukuvi Chemical Industry Co., Ltd.
- Inventors: Jiro Ishiguro; Kazuo Maruya
- Web page: https://patentgrep.com/patent/US4400433A

## CPC

- C04B 35/536: based on expanded graphite {or complexed graphite}
- F16J 15/20: Packing materials therefor
- Y10T 428/30: Self-sustaining carbon mass or layer with impregnant or other layer
- C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE
- F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Flexible graphite granules prepared by a process comprising agitating vermiform expanded graphite masses having a bulk density of not more than 0.01 g/cc in a liquid have been found to be extremely suitable for producing a flexible graphite product, even with a low density, having an excellent shape-retaining property as well as a shapeability and exhibiting strong mechanical strengths.

## Claims

### Claim 1

A molded graphite product produced by a process comprising:
immersing veriform expanded graphite masses having a bulk density of not more than 0.01 g/cc in a liquid which is inert to the graphite and capable of wetting at least the surfaces of the graphite masses, said liquid being employed in an amount of at least 25 times, by weight, that of the vermiform expanded graphite masses;
agitating the graphite masses in the liquid for a time sufficient for the graphite masses to undergo compression and density-increase and form graphite granules;
separating the graphite granules from the liquid;
drying the graphite granules; and
molding the dried graphite granules by pressing to have a density of 0.8 to 2.0 g/cc.

### Claim 2 (depends on 1)

A molded graphite product according to claim 1, wherein the process further comprises feeding the dried graphite granules to a screw extruder with a screw having a predetermined compression ratio and extruding the dried graphite granules therethrough to obtain flexible graphite granules having a further increased bulk density.

### Claim 3 (depends on 1, 2)

A molded graphite product according to claim 1 or 2, which is in the form of a packing ring and has a density of 0.8 to 1.1 g/cc.

### Claim 4 (depends on 1, 2)

A molded graphite product according to claim 1 or 2, which is in the form of a pipe.

### Claim 5 (depends on 1, 2)

A molded graphite product according to claim 1 or 2, which is in the form of a round rod or angular rod.

### Claim 6 (depends on 1, 2)

A molded graphite product according to claim 1 or 2, which is in the form of an article having a relatively large length and having a semi-circular or U-shaped cross-section.