Patent ID: 8728224
Filing Date: 2014-05-20
Classification: C04B

Abstract:
1. A ceramic molding composition comprising a water-soluble binder comprising a water-soluble hydroxypropyl methyl cellulose having a methoxyl substitution of 28 to 30 wt % and a hydroxypropyl substitution of 5 to 7 wt %, and a ceramic material, wherein the binder has a syneresis value in aqueous solution form of at least 30 wt % and a clay heat gel strength of at least 0.5 kgf, and wherein the term “syneresis” refers to the separation of water from a gel due to contraction of the gel, and the “syneresis value” of a cellulose refers to a percentage of the total weight of water and water vapor exuded from a cellulose gel divided by the weight of the gel, and is obtained by the method that 30 g of 2.5 wt % aqueous solution of water-soluble hydroxypropyl methyl cellulose kept at 20° C. is placed in a 30-ml beaker and heated in a household microwave oven (max. 600 W) at the low power (about 180 W) for 3 minutes to form a gel, the gel is weighed, then transferred to a petri dish and heated in the microwave oven under the same conditions for 4 minutes, and at this point, the total weight of the water and water vapor separated from the gel is measured.