The flow properties of the effluent (toluene) and the separation of the oil green (mixture of yellow and blue dyes) from the toluene solution has been investigated through the centrifugal liquid chromatograph in which the quartz powder or silica gel were used as the fillers. The.followings were found : (1) the volumetric flow rate against revolution rate N was expressed by Q=KN² where K is a constant referred to physical properties of the filler and to the structure of equipment, (2) retention time, tR was proportional to π (r²₃r²₂) h/Q and proportionality constant showed e (1+K) where π (r²₃r²₂) h, and K were the packing volume for filler, ratio of porosity and partition coefficient respectively, (4) retention volume of each dye was proportional to the packing amount of filler and the proportionality constant was confirmed to be expressed as ε (1+K) /ρ (1-ε) where p is the density of filler, (5) oil green separates into yellow dye and blue dye by silica gel, whereas does not separate by quartz powder, (6) the followings were recognized from consideration on resolution and number of differential cylindrical ring that the mechanism of separation in centrifugal liquid chromatograph follows the same mechanism as the plate theory in column chromatograph (C. C.) presuming the concentric array of differential cylindrical rings in an equal volume in replace of the plates in C. C.

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Influence of the degree of pigment dispersion with roll milling on flow property of the highly viscous suspensions (volume fraction 0.036-0.13) has been investigated for seventeen widely used pigments.
Pigment was first premixed with linseed oil varnish with viscosity of η=7.0 Pa¥s at 30°C and the premixed suspension was milled repeatedly by a three-roll mill of 0.127 m dia. The product suspension was sampled after every pass through the mill and flow property and fineness of it were measured by a cone-plate viscometer and a grind gauge, respectively.
Newtonian behavior of clay suspensions at premixing were not changed with roll milling. Suspensions of silicas and asbestoses were Casson plastic at premixing but their yield stresses decreased remarkably after the first pass through the mill. Organophilic bentonite suspension was newtonian at premixing but its yield stress increased with improvement of the degree of pigment dispersion by repeated milling.
There rheological differences depending on physical properties of pigments are qualitatively discussed in the light of Casson's equation of viscosity. The formation of some structure and its apparent volume fraction are considered to be reflected on yield stress and Casson viscosity.
Dependence of fineness (grind gauge value G) on production rate Qm and the number of passes N was found for bentonite suspensions as follows, GocN^-0.25Qm^0.38

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Acrylic copolymers with different calculated glass transition temperature (Tg calc.) were prepared by varying monomers composition. The melting viscosity (η) of each copolymers was measured and its apparent activation energy of flow (ΔE (η)) was calculated from the relation between log η and 1/T. Moreover, the dynamic viscoelasticity of acrylic-melamine resin on curing process was measured at various temperatures and its apparent activation energy of cure (ΔEa) was determined. The results showed that η of copolymer increased and the rate constant of cure (k) decreased with an increase of Tg calc. ΔEa increased with an increase of ΔE (η) lineally. These results indicate that the curing behaviour of acrylic-melamine resin used in the present study is a diffusion control reaction affected by the viscosity of the reaction system, relating to the segmental mobility of the main chain in acrylic copolymer.

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The separation conditions of high performance liquid chromatography on methyl and butyl melamine resins for coatings were studied to determine the molecular species distributions. Silica packings bonded with octadecyl (C₁₈), octyl (C₈), dimethyl (C₂), phenyl (Ph), nitrile (CN), diol (OH), and amino (NH₂) groups were packed in a stainless-steel tube (4. 6 mm inside diameter, 150 mm length) by the sularry method and were used in the reversed phase mode.
The CN bonded silica packings with medium polarity which have scarcely been used for the. oligomer separation show good performance with water/methylalcohol carrier. The OH, NH₂ bonded silica packings with strong polarity showed very poor separations with weak retention ability. The-order of retention ability is C₁₈>C₈>Ph≅.C₂>CN and agreeds with the common rule in reversed phase partition mode.
In the case of C₂, Ph, C₈, C₁₈ bonded silica packings, it was found that the higher molecular-component of conventional butylated melamine resins did not elude at reasonable time in water/ methylalcohol carrier.

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