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New trisazo dyes from 3,5-bis(p-aminophenyl)-1,2,4-triazole and 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole which are found to have no toxicity and no carcinogenicity, and 2,5-bis(p-aminophenyl)imidazole have been prepared to replace benzidine type dye, Direct Deep Black EX. Dyeing with these dyes was carried out on cotton, silk, wool and 6-nylon. These dyes have been shown to have very good dye-ability and also to be very similar to benzidine type dye in colour and fastnesses to light and washing.

The equilibrium adsorption of Orange II by Vinylon has been investigated over a wide range of the dye concentration in the dyebath. The internal adsorption isotherms have been calculated from the results. They differ considerably from the linear form assumed in the formulation of the dyeing theory and far from a Langmuir or a Freundlich relation.Taking into consideration a heterogeneity of the fibre, it has been assumed the Vinylon surface to be composed of three groups of dyeing sites having the different affinities for dye. The internal adsorption isotherms may be represented by the following equation-assuming a Langmuir adsorption of the dye on each group of dyeing sites-.The amount of dye adsorbed on the fibre surface was calculated using the equation (1). There was good agreement between the observed and the calculated values.The saturation values [S] for each group of dyeing sites was independent of the concentration of salt in the dyebath but K for each group considerably dependent of that.The heat of dyeing for each group of dyeing sites was calculated. It was found that there were large differences in the heat of dyeing between the groups dyeing sites.

Disperse dyes were synthesized from 1, 2, 3, 4-tetrachloroanthraquinone. They showed good dyeing properties for Tetoron through high pressure dyeing treatment, although their properties for Acetate were not satisfactory. The dyes containing aryl group showed sun-fastness of 6 grade or above and sublimation-fastness of 4-5 grade. Even the dyes without aryl group showed improved fastness against sunlight, abrasion, washing, and sublimation over the corresponding 1, 4-disubstituted anthraquinones.

The absorption isotherms of four disperse dyes for polypropylene fibers were determined at various temperatures. The affinity, heat of dyeing and entropy of dyeing were calculated from the thermodynamical treatment. The heasts of all four dyes investigated were all negative, so the binding process was exothermic. The affinity of the dye for polypropylene was found to increase with the increase in the hydrophobic character of the dye. The increase in the hydrophobic character of the dye, however, causes the decrease in the heat and entropy of dyeing. This result shows that the higher affinity of the hydrophobic dye comes from the decrease in the entropy of dyeing. From a consideration of the thermodynamical data, it is assumed that the breakdown of so called “iceberg” water structure in the vicinity of the hydrophobic dye takes place in the course of the binding process. The interaction between polypropylene fibre and disperse dye is explained by using the following concept that the binding process involves two main effects: (1) an exothermic interaction (may be dispersion force) (2) an entropic interaction (the formation of a so called. “hydrophobic bond”)

A series of dispersing dyes containing a β-methyl group and an α-amino group have been synthesized in such a way that those substituents are not located in adjacent positions to each other on the ring structure. The starting compounds employed were the Diels-Alder adducts obtained from 2, 3-dimethylbutadiene with naphthazarine and with 5-nitro-2, 3-dichloronaphthoquinone. Their dyeing qualities for Acetate and Tetoron were then tested. It has been reported that the presence of a methyl group in an adjoining position to the amino group lowers the fastness against sunlight due to increased electron density at the amino group. The dyes prepared in the present study thus showed improved fastness of 4-6 grade for Acetate, that for Tetoron being around 3 grade. They also revealed excellent resistance against washing and sublimation, though their dyeing qualities remained almost the same as that of 2-methylanthraquinone derivatives. Shift of the maximum absorption peak toward the longer wave length was noted in ethanol when the methylanthraquinones were compared with anthraquinone derivatives containing no methyl group.

To investigate the mechanism of dyeing of Vinylon with basic dyes, the absorption isotherms of C. I. Basic Blue 9, C. I. Basic Violet 3, C. I. Basic Bed 2, C. I. Basic Blue 26, C. I. Basic Violet 10 and C. I. Basic Orange 2 in presence or in absence of salt were determined at 80°C.The isotherms obtained were represented approximately by the following equation which was a linear combination of two functions.It is considered that in the equation (1), the term K[D]s[S]/1+K[D]s correponds to the dyeing mechanism which takes place by adsorption of dye cations by carboxyl anions in Vinylon, and that the term K′[D]s corresponds to the dyeing mechanism which takes place by solution of dye into the fibre.By the use of the equation (1), the saturation value, the number of carboxyl groups in Vinylon, can be calculated from the isotherms. The values calculated were ca. 8m. mol/kg fibre. ([D]F and [D]s are the concentration of dye in the fibre and in solution, [S] the saturation value, K, K′ constant).

5-Nitro-2, 3-dichloro-1, 4-naphthoquinone (1a) and its derivatives (2a)-(7a) were synthesized. These were reduced with S2O3 in conc. H2SO4 to give 2, 3-dichloro-1, 4-dihydroxy-5, 8-naphthoquinone-8-imine (1b) and its derivatives (2b)-(7b), their maximum light absorbancy and dyeing ability of acetate, Vinylon, Amylan and Terylen have been investigated. Of these compounds tested, (1b) and (4b) showed excellent and clear dyeing than others. Among the textiles tested for dyeing, Amylan was the best with some dullness while Vinylon was slightly inferior than others. Terylen showed the same dyeing efficiency as that of acetate by dyeing at 100°C without carrier. Fastness of dyes was superior in Therylen and inferior in other fibers.

6-Chloroquinizarin was synthesized in good yield from 4-chlorophthalic anhydride and hydroquinone in the presence of sodium aluminum chloride. Disperse dyes of general formula, 1, 4-di (NHR)-6-chloroanthraquinone (R= H-, CH3-, C2H5-, n-C3H7-, n-C4H9-, n-C6H13-, HOC2H4-), were then prepared and their dyeing properties on Tetoron examined. The colors of dyed cloth varied from violet to greenish blue. Their dyeing affinity was good ; perticularly the dyes with R= H-, CH3-, C2H5- showed excellent affinity. The dyes with R=, HOC2H4- showed good fastness against sublimation. When compared with the corresponding 1, 4-disubstituted anthraquinones, the λmax of these dyes in ethyl alcohol shifts toward longer wave length, the value of emax is larger and the melting point is higher. The light-fastness, however, remained almost in the same order of that of 1, 4-disubstituted anthraquinones.

Disperse dyes, 6-phenoxy-1, 4-disubstituted anthraquinones and 6, 7-diphenoxy-1, 4-disubstituted anthraquinones were prepared and their dyeing properties on acetate and Tetoron examined. The colors of dyed cloth varied from violet to blue. Their dyeabilities on Tetoron were good; particularly, 6-phenoxy-1, 4-disubstituted anthraquinones sho-wed excellent affinities to Tetoron in high temperature dyeing treatment. Their dyeabilities on acetate, however, were not satisfactory. The λmax of 6, 7-diphenoxy-1, 4-disubstituted anthraquinones in ethyl alcohol shifts toward longer wavelength than that of the corresponding 1, 4-disubstituted anthraquinones. Their light-fastness on acetate was good, and their abrasion-as well as wash-fastness was excellent. They, particularly 6, 7-diphenoxy-1, 4-disu-bstituted anthraquinones, showed good sublimation-fastness.

The equilibrium absorptions of C. I. Direct Yellow 12, C. I. Direct Red 1 and C. I. Direct Red 2 by Vinylon have been investigated at 90°C. The salt-dye ratio p and the substantivity ratio q were calculated from the results. For C. I. Direct Red 1 and C. I. Direct Red 2, a logarithmic p, q plot is represented by an approximate single line, and this result is found in agreement with the theoretical deduction that the isothermal relation between the substantivity ratio and the salt-dye ratio is independent of the composition of the equilibrium solution.On the other hand, for C. I. Direct Yellow 12, the result does not agree with the prediction of the direct dyeing theory, and the substantivity ratio increases with increase of the salt concentration in the dye-bath.To explain this abnormal dyeing behavior, it is assumed that in the case of C. I. Direct Yellow 12, the dye molecules in the solution are easily dehydrated by added NaCl even at the dyeing temperature and the degree of hydration of the dye molecules decreases with increase of NaCl concentration in the dye-bath. Such a dehydration of the dye molecule increases the chemical potential of dye in the solution and decreases the chemical potential of dye in the fibre, so the substantivity ratio increases with an increase of the salt concentration in the dye-bath.