GB696992A - Improvements in means and method for producing a continuous sheet of integrated mica - Google Patents

Abstract

696,992. Mica. HEYMAN, M. D. Nov. 30, 1951 [Dec. 15, 1950]. No. 28165/51. Class 70, A continuous sheet of integrated mica is produced by reducing pieces of mica to flakes of less than four microns thick while immersed in an evaporative liquid medium, directing a continuous flow of liquid and flakes into a static chamber in which the flakes settle downward through the liquid and are deposited on the upper side of an upwardly sloping and upwardly moving web, thereafter extracting residual moisture from the deposit of flakes to form an integrated sheet, and finally removing said sheet from the web. The liquid media may be water, methyl alcohol, carbon tetrachloride, toluene or xylene. Mica is fed from a container 55 via a shoot 54 fitted with a vibrating device 56 into a funnel 52 which feeds to disintegrators 40, 42 and 43. Liquid such as water which may have been treated in purifier 10 is passed at uniform intervals of time, in uniform amounts and at a required pressure through proportioning pump 26, booster pump 27 and then into the disintegrators in which the mica is split to a thickness of about four microns. Longer particles are intercepted by dam 58 while passing down shoot 41 and these are again split in disintegrator 60. The flakes then pass to a classifier 64 which is reciprocated at 200 times per minute. Larger flakes pass to a further disintegrator 72 before being restored to the main flow, which is then discharged from shoot 70 and onto conveyer means 81 at a point at the bottom of a sloping tank 77. The flakes settle on the outer nylon web 83 and are subjected to vacuum treatment at 95 and at 92 to remove much of the water. The mica now in sheet form 98 is dried on a heated pulley 91 and in oven 100 and is then wound on drum 101. Specification 615,489 is referred to.