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The steady flow and dynamic viscoelastic properties of disperse systems consisting of polystyrene copolymer particles of different sizes in polystyrene solutions were measured by means of rotating cylinder type rheometers over wide ranges of temperature, rate of shear, and frequency. The yield values, evaluated by use of the modified Casson equation for disperse systems, were found to be independent of temperature. Time‐temperature superposition was applied to the flow curves and the frequency dependence curves of the dynamic properties, giving identical shift factors which obeyed the WLF type equation and were almost independent of the size and content of the particles. The yield value increased with increasing particle content and polymer concentration in the disperse medium. The smaller the particle size, the larger the yield value. The frequency dependence curves of the storage shear modulus G′ and the loss modulus G″ showed second plateaus lower than the rubbery plateau at lower frequencies. The correlation between the yield value and the complex shear stress is discussed.

Changes of thickness with pressure in the measuring were examined, and the following empirical formulawas obtained.log T-log T0=-KW (1) or T=T0e-K/w (2) where, T; thickness at which pressure is WT0; thickness at which is zero and which especially we designated the intrinsic thicknessW; measuring pressureK; constant decided with paper propertiesK';1/log10eK=2.3026K

Hmax and smoothness were measured by needle touch type unevenness tester and Bekk automatic smoothness tester, respectively, and relation between h and Hmax or smoothness was examined.It was found that h was closely conected with Hmax or smoothness.When thickness of paper was measured in superposition by micrometer, and h was obtained with the formula showed in part 1, thereby the surface condition of paper is briefly known.

Disperse systems such as various suspensions, emulsions and filled polymers show remarkable nonlinear viscoelasticity even at strains smaller than 10%. A practical and general method has been proposed to determine the nonlinear viscoelastic functions G'1, G"1, G'3, G"3, and so on by the analysis of non-sinusoidal shearing stress as a result of forced sinusoidal shear strain.The above nonlinear functions were evaluated for disperse systems of polystyrene solution and styrene-divinyl benzene copolymer latex at various temperatures. In general, the frequency dependence curves of all the functions are rather flat and become less sensitive to temperature as the temperature rises. To the curves at different temperatures, the so-called time-temperature superposition can be applied; the shift factors determined in the course of horizontal shifts of curves for various functions are quite the same, and are independent of the strain amplitude. The master curves of the nonlinear functions manifest plateaus in the low frequency region, where the polymer solution itself shows rapid changes in G' and G". The height of the plateaus increases with increasing latex content.

The measurement methods of paper by the porosity testers of six kinds, Gurley densometer, Emiel Greiner porositymeter, Schopper air permeability meter, Emanueli porositymeter, Oken type denso-aspero meter and smoother, were examined, and further the relationships between these testers were theoretically and experimentally obtained.(1) In the relation between the Gurley densometer (G) and the Emiel Greiner porositymeter (E), the theoretical formulas agreed well with the experimental values. But, in the range of low air resistance, the experimental values by the Emiel Greiner porositymeter were smaller than the theoretical ones, whereas in the range of high air resistance, that relation was reverse.The relationship between two testers was shown by the following theoretical formulas.Ve=83046.6/0.803tG+513.34 … (1) VE= (979+0.675Ve) /1033 Ve … (2)were Ve and VE in cc/5mintG in sec/100cc (2) In the relation between the Schopper air permeability meter (S) and the Gurley densometer or the Emiel Greiner porositymeter, the theoretical formulas agreed very well with the experimental values.Especially, the theoretical formula of relation between the Schopper and the Gurley was in better agreement with the experimental values than that relation between the Emiel Greiner and the Gurley.The relationship between the Schopper and the Gurley was shown by the following theoretical formula.tG=24096.38/Vs … (3)where tG in sec/100ccVs in cc/5in(3) In the relation between the Emanueli porositymeter (M) and the Gurley densometer, the theoretical formula also agreed well with the experimental values, and this formula was as followsAM=43.478×tG/d … (4) ortG=523.023×P1/P2… (5)where AM in a unit of Emanuelid is thickness in cmtG in sec/100ccP1 or P2 is a differernt pressure (4) The Oken type denso-asperometer (O) and the Smoother (SM) have close relation with usual tester as the Gurley densometer etc.These testers were suitable for a manufacturing process test of high air resistance paper because these testers have superior accuracy and especially made the rapid test possible.The relationship between the Gurley and the Smoother was shown by follows experimental formulas;in the case which standard head was used, log HSM=-1.146log tG+5.122…(6) in the case which cramp type head was used, log Hsm=-0.638 log tG+4.247… (7)The relationship between the Gurley densometer and the Oken type denso-aspero meter was shown by the following experimental formula, log T0=0.965 log tG+0.0818… (8)

The nonlinear viscoelastic functions G1′, G1″, G3′, and G3″ were evaluated for disperse systems of polystyrene solution and styrene‐divinyl benzene copolymer particles at various temperatures ranging from 10 to 70°C over the frequency range from 12 to 1/256 Hz. In general, frequency dependence curves of all the functions are rather flat and become less sensitive to temperature as the temperature rises. To the curves at different temperatures, the so‐called time‐temperature superposition can be applied; the shift factors determined in the course of horizontal shifts of curves for various functions are quite the same and are independent of the strain amplitude. Master curves of the nonlinear functions manifest plateaus in the low frequency region, where the polymer solution itself shows rapid changes in G′ and G″. The height of the plateaus increases very rapidly with increasing particle content. All the moduli G1′, G1″, G3′, and G3″ decreases first rapidly and then slowly with increasing strain amplitude u...