An expedient experimental method has been proposed to characterise the mixing process and performance of powder mixers based on the measurement of changes in the color of the mixture with operating time. To evaluate the mixing and dispersing characteristics among the different types mixing equipment, adhesive fine calcium-carbonate (white) and iron-oxide (dark red) powders were applied as a bulk and a tracer, respectively. The influence of the mixing procedures on the calibration curves of the relationship between the lightness value of the mixture and the tracer concentration has been discussed based on the agglomerate size of the tracer powder. The degree of attainment to the final dispersing state, η_I was defined as an index of the intensity of mixing or dispersing process of the powder.
It has been shown that the characteristics of mixers are classified into three groups according to the dispersing process by using the index η_I.

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The zeolite-filled membranes were made by a casting technique using polybutadiene and polydimethylsiloxane as the membrane material. The relationship between the dispersion state of zeolite in the membrane and the adsorption characteristics of water vapor were discussed. As the results, the equilibrium amount of water vapor adsorbed on zeolite in the membrane was approximately one-half the amount adsorbed on zeolite only. The adsorption rate of water vapor was dependent on the dispersion state of zeolite, the thickness of the membrane and the kinds of the membrane material. The modified particle-membrane diffusion model to describe the dispersion state of zeolite was presented on the basis of the transport through the membrane.

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A pre-mixing experiment was carried out on materials for toner with a high-speed type mixer using mixing time as a variable. The obtained pre-mixture was kneaded under a definite condition, and then the keaded material was pulverized and classified. On the basis of the evaluation of the kneaded state and charging characteristics, the effect of pre-mixing time was examined.
The results show that the agglomerate area ratio in the kneaded material and the CCA (charge control agent) concentration on the surface of the toner particles enable the assessment of the kneaded state and the consideration of the pre-mixing process. Furthermore, it is clarified that an excellent kneaded state is obtained at longer pre-mixing times, and the condition of CCA dispersion on the surface of the toner and the charging characteristics is determined by the kneaded state.

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This paper presents the influence of agglomeration upon the flow property of the slurry low pressure molding. (Zr, Sn) TiO₄ powder agglomerate was pulverized by a high speed mixer. The agglomeration state was evaluated by tapping the density and residual by #350 sieving. The flow property was measured by the viscosity and scratch of a grindmeter. The dewaxing properties were evaluated by pore size distribution, the fraction of residual binder after dewaxing, and the rejection ratio of greenware due to crack.
Pulverization of the agglomerate reduces the thixotoropy of the slurry, contributing to uniform pore size and residual binder distributions. They all contribute to reducing cracks in greenwares.

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Composite particles with a double layer or with a matrix type layer were prepared by a two-step mechanofusion process. Stainless particles (mean particle diameter: 35μm) were used as core materials. Zirconia particles (0.3μm) were used for the primary coating of the core particles in the first mechanofusion process.
(1) The structure of the coating layer on primary composite particles changed from agglomeration to consolidation with increasing mechanofusion treatment time. The transformation of the coating layer structure could be controlled under water cooling conditions during the mechanofusion process.
(2) The composite particles with a double layer could be obtained in such a way that the primary composite particles with a consolidation layer were coated with Cu particles.
(3) Zirconia particles were peeled off from the consolidation layer of the primary composite particles when spherical stainless particles were used as secondary coating materials.
(4) The composite particles with a multicomponent dispersed layer could be obtained in such a way that the primary composite particles with an agglomeration layer were coated with flaky stainless particles.

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