Patent ID: 6645931
Filing Date: 2003-11-11
Classification: C11D

Abstract:
A solid-shaped detergent comprising particles for detergent, comprising a particle capable of releasing a bubble from an inner portion of the particle in a process of dissolving the particle in water, the bubble having a size of one-tenth or more of a particle size of the particle, and wherein the particles have a dissolution rate of 90% or more, under conditions where the particles are supplied in water at 5Â° C.; stirred for 60 seconds under the stirring conditions that 1 g of the particles are supplied to a 1-L beaker having an inner diameter of 105 mm which is charged with 1 L of hard water having 71.2 mg CaCO3/L, wherein a molar ratio of Ca/Mg is 7/3, and stirred with a stirring bar of 35 mm in length and 8 mm in diameter at a rotational speed of 800 rpm; and filtered with a standard sieve having a sieve-opening of 74 &mgr;m as defined by JIS Z 8801, wherein the dissolution rate of the particles is calculated by the Equation (1):Dissolution Rate (%)=[1âˆ’(T/S)]Ã—100â€ƒâ€ƒ(1) wherein S is a weight (g) of the particles supplied; and T is a dry weight (g) of insoluble remnants of the particles remaining on the sieve when an aqueous solution prepared under the above stirring conditions is filtered with the sieve; wherein the particles have a bulk density of 500 g/L or more; and wherein the particles comprise base particles for supporting a surfactant and/or detergent particles prepared by supporting a surfactant to the base particles, wherein each base particle comprises 20 to 90% by weight of a water-insoluble inorganic compound, 2 to 30% by weight of a water-soluble polymer and 5 to 78% by weight of a water-soluble salt, wherein said base particle has a localized structure in which larger amounts of the water-soluble polymer and/or the water-soluble salt are present near the surface of the base particle rather than in the inner portion thereof, and wherein said base particle is obtained by the steps comprising carrying out spray-drying of a slurry with no surfactant.