Toner particles were perimentally produced in a high-speed shear mill by applying multiple coatings of three toner constituent materials to core (resin) particles having an average diameter of 14μm. To discover the optimal toner particle characteristics, the order of coating application and shear mill rotation velocity were varied. The following findings were obtained:
It was possible to design toner particles using the dry coating method in which toner constituent materials, such as a coloring agent, a charge control agent (CCA) and a flowability-enhancing agent were coated sequentially on thermoplastic resin core particles. This result suggests that the composite production process currently used in the kneading and pulverizing method can be simplified.
It was demonstrated that to design toner particles of superior functionality, such as improved charging and fixing characteristics, coatings of coloring agent, CCA, and flowability-enhancing agent, in that order, yielded the best results. Also, a high-speed shear mill rotation velocity of 16.7rps yielded the best toner particles having high functionality and good flowability.

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Several tablet cores were prepared by various granulation methods and were coated by using an aqueous or organic film coating. The adhesive strength to remove the tape (tape adhesive strength) or film (film adhesive strength) from a unit area of the tablet core surface was measured by using adhesive tape.
It was found that the tape adhesive strength was nearly equal to the tensile stress of the tablet core surface. This is because a relatively large amount of the tablet core surface adhered to the tape after testing.
For the aqueous coating, the film adhesive strength was influenced by the hardness, granulation method, composition and moisture content of the tablet core. By evaluating the tape adhesive strength of the humidified tablet core, the film adhesive strength was predicted. The film adhesive strength was greater than that of the organic coating, because the aqueous film liquid penetrated the tablet core during the coating process.

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In order to achieve a high solid circulation rate in a spouted bed with three draft-tubes without generating slugging fluidization but with uniform circulation in each draft-tube, the relationship between the opening ratio of perforation plate, the air velocity in the colum, U, and the space between draft-tube and perforation plate, s, was studied.
When the opening of perforation plate was designed for the air velocity in the outside of the draft tube to be about one-fifth of the terminal velocity of a particles used, the solid circulation rate, W, under non-slugging fluidization increased linearly with U at a rate increasing with s. However, U in such a steady circulation, had an upper limit, decreasing with increase in s. Thus, the maximum of W at the upper limit of U reached about 3kg/s at 0.53-0.8 of s.

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A new aqueous polymeric enteric coating system was developed with the aqueous dispersions of hydroxypropylmethylcellulose phthalate (HPMCP) nanoparticles prepared by the emulsion solvent diffusion method. The average diameter of HPMCP nanoparticles (pseudolatex) was 120nm with a polydispersity index of 0.172. The enteric coating of riboflavin granules with the present system was successfully conducted using a fluidized bed coating.
To obtain satisfactory acid resistance (i. e. enteric properties) of the coated granules with HPMCP nanoparticles, the coating film thickness needed to be 10μm or more. The coating amount required to obtain satisfactory acid resistance of the coated granules with HPMCP nanoparticles was found to be much smaller than with the pulverized HPMCP available on the market. This is because the coating film with HPMCP nanoparticles was closer and more uniform than that with pulverized HPMCP particles. The equation to predict the amount of polymer required for satisfactory enteric coating was proposed in the present study.

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