The influence of operating conditions on the experimental results were investigated and the standard test conditions were established.
After the compression experiments on several fibers the possible evaluations were discussed, and it is proposed to characterize the bulkiness of fibers by the compression energy, resilience and fatigue ratio given as the ratio of the energy of deformation in the first and 2 nd cycles.
Compressional index expressed in the forms of product of compression energy, resilience and fatigue ratio are defined as the values which collectively evaluate the bulk compression characteristics of fibers.
The evaluation by compressional index shows a good agreement with handling test results.

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Aqueous solution of the mixture of polyvinyl alcohol and vinyl methyl ether-maleic acid copolymers is extruded into coagulating bath which is used for spinning of vinylon. The fiber thus obtained was stretched, dried, heat-treated, and formalized.
The fiber is superior to ordinary vinylon in dyeability, but inferior in tenacity.

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Fibers prepared from mixture of polyvinyl alcohol and polyacrylic acid (PA) were heat-treated and formalized. Resistance of these fibers to water, acid, and alkali was examined with the following results
Resistance of unformalized fibers to water increase with heat-treatment and also with increased amount of PA. Above all, boiling water resistance of fibers containig 25_??_30% PA, subjected to heat-treatment at 220°C, is fairly high and is approximately comparable with resistance of ordinary vinylon. Resistance of formalized fibers to boiling water is good.
Resistance of formalized fibers to hydrochloric acid increases as with content of PA is increased, whereas their resistance to alkali decreases

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When domestic and wild silkworm cocoon fibroin fibre, from which sericin has been completely removed, is observed under the electron microscope, while it is being moderately broken down with hydrogen peroxide or sodium hydroxide, 400-600 Å diameter fibrils, formed by a large number of 100-150 Å diameter and 0.2-0.4μ diameter, 0.6-0.8μ width sparse fibrils were noticed. During the fibre break-down process, regardless whether it is domestic or wild cocoon fibre, 0.2-0.4μ diameter fibrils possess a characteristic of developing into band-form fibrils of 1.0-1.2μ width when treated with hydrogen peroxide or sodium hydroxide. With the exception of wild silkworm and one group of the domestic cocoon (Kuniichi, Kuniichikai, Koishimaru, Chinese etc), the middle layer fibroin fibre of the common domestic cocoon is weak against chemicals such as hydrogen peroxide and sodium hydroxide, different from those the outer and inner layer fibroin fibres.
The following is on the detail electron microscopic study of fibroin fibre fibrilization based on the observations of fibre cross-section of replica test material.
The results on the cross-sections of cocoon fibre and sericin-free fibroin fibre being that much finer, comparatively uniform fibroin of 0.2-0.4μ diameter fibrils and 0.6-0.8μ width fibrils, totalling around 1, 000 were noticed, compared to the fibril 0.3-3μ diameter noticed under the ordinary microscope. In order to observe the fibril structures more accurately, the cross-section was treated gradually and broken down with ten per cents solution of hydrogen peroxide or one normal solution of sodium hydroxide the results being that still finer, fibrils of 400-600 Å diameter were accurately observed.

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In the tin finish on silk, the authors used degummed raw silk and “Habutae” fabrics as samples and condensed sodium phosphates, phosphates and sodium meta-Silicates used as assistant agents. The treatment was conducted with stannic chloride with the following results:
(1) The weight percentage increases in proportion to the number of repetition of treatment in every case of condensed phosphates, phosphates and sodium meta-silicates.
(2) The weight percentage also increases when treated with high concentration of condensed phosphates or sodium meta-silicates, but the percentage decreases considerably when treated with 0.5_??_0.12% solution. The percentage, however, increases gradually when treated with the still lower concentrated solutions.
(3) When compared with sodium salts and potassium salts, the potassium salts are compara-tively less influenced by temperature or concentration and the weight percentage is comparatively stabilized.

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The absorption of binary mixtures of Solacet dyes by Vinylon has been studied over a wide range of dye concentration and temperature. It has been found that in the mixture dyeing the amount of one dye absorbed was reduced in the presence of the other dye, but in all cases the total molecular concentration of two dyes absorbed was more than that of individual dyes absorbed singly. Assuming that the Solacet dyes, whan applied in admixture, are absorbed by Vinylon without mutual interaction, the equations have been derived from the thermodynamical treatment in order to correlate the amount of each dye absorbed from the mixture dye-bath with the affinities of individual dyes in the single dyeing. The reduction in the amount of one dye absorbed, caused by the presence of the other dye in the same dye bath, can be explained by these equations quantitatively.
The affinity and the heat of dyeing of each dye in the mixed dyeing are determined by the thermodynamical treatment. The values for the affinity and the heat of dyeind are in fair agreement with those in the single dyeing.

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