In order to elucidate the maturity process of lint during the growing process of cotton fiber, the immaturity ratio (I), perimeter (p), weight fineness (W), wall thickness (t) of lint were daily measured by arealometer. Cotton variety used for this research was “Rikuchimen Kanno No.I”, a sort of upland cotton. Wall thickness and weight fineness of lints increased linearly from 24th day to 40th day after flowering and later showed constant value until the boll opening. Perimeter of lint showed a constant value from 20th day after the flowering to the boll opening. Maturity ratio (I) decreased linearly from 24th to 40th day after the flowering and later showed a constant value until the boll opening. From above experiments, it may be concluded that the elongation growth of lint completed by 22nd day after the flowering, the growth of wall thickness begined from 20th day after flowering, wall thickness increased linearly and completed 40th day after the flowering, and cellulose was synthesized and deposited in lint at the same rate during the secondary wall formation. The relationships among immaturity ratio (I) and immaturity (D), perimeter (p), weight fineness (W) and wall thickness (t) are discussed.
Maturity index and fineness of lint during the growing process of cotton fiber were daily measured by causticaire method in order to make clear the maturing process of cotton fiber. Then these same samples were measured by the various measuring methods of fineness, which are based upon different principles and assumptions, and they were compared. The cotton variety used for this research was “Rikuchimen Kan-no No.1”, a sort of upland cotton. Following results are obtained. 1) Maturity index and fineness of lints increased linearly from 21st day to 40th day after flowering and later showed constant value until the boll opening. From above experiments, it may be concluded that the elongation growth of lint completed by 22nd day after the flowering, wall thickness increased linearly and completed 40th day after flowering, and cellulose was synthesized and deposited in lint at the same rate during the secondary wall formation. 2) Measured value of micronaire fineness, causticaire fineness and arealometer fineness, of lints whose maturity index were above 60, well agreed with each other, but the frequency of measurement should be increased by causticaire and arealometer methods in extremely immature lints.
Acetalization of polyvinyl alcohol powder and fiber with azelaic acid aldehyde OHC(CH2)7 COOH was undertaken. Polyvinyl alcohol can be easily acetalized both in homogeneous (aqueous solution) and heterogeneous (fibrous) reactions, and the degree of acetalization may be determined by the titration of carboxyl groups. But it was difficult to obtain fibers which were sufficiently resistant in boiling water. Viscosity measurement of aqueous solution showed that this acetal is a typical polymeric electrolyte.
Isotropic polvinyl alcohol filaments were stretched to various degrees in different media. For the stretched filaments, the tensile strength and elongation were measured in both wet and drv states. Shrinkage was also observed in gradually heated water. The changes of filament length at the softening point and at the solubility point were calculated from the standard length. This has led to the conclusion that the softening point can be characterized as the point at which Young's modulus becomes very low. Since the filament length at solubility point corresponds to the length at the effective draw, some frame-work structure must be considered in the inner part of the filament. The shape of shrinkage curves can be interpreted qualitatively considering the distribution of secondary bond strength.
To determine the value of pentosan in pulp or wood, the treatment with mineral acid (usually HCl solution) may be carried out in the given conditions, especially as to the velocity of distillation. The apparatus, as shown in the figure, consists of an automatic HCl feeder, a dropping funnel, a connection tube, a distilling flask and a water-cooled condenser. By using this apparatus, 1) It is no longer required to add HCl by hand daring the HCl treatment. 2) Because the head of HCl solution in the dropping funnel is constant, dropping velociety of HCl into the distilling flask is also kept constant. 3) Subsequently, this makes it easy to maintain the constant distillation velocity in the given conditions.
The displacement of back roller and coloured fibers that had been inserted into the sliver before drafting, were observed (Fig. 1). Then the effect of ratch and draft ratio for the distribution of the velocity-change-points were investigated. When the ratch is widened, the center of the distribution -E(_??_)- shifts from the side of front roller towards back roller (Fig. 2), and the distribution range -E(s2)- widens (Fig. 3). The variance of center by time -V(_??_)- becomes larger (Fig. 4). E(_??_), E(s2) and V(_??_) are given in formulae (2), (3) and (4). When the draft ratio becomes larger, the center shifts from the back roller towards the front roller (Fig. 5) and its range is limited. As the ratch besomes smaller, the form of distribution becomes nearly normal, but when large, its skewness becomes positive (Fig. 7_??_Fig. 10).
(Faculty of Technology, Tokyo Metropolitan University, Fukazawa-Cho, Setagaya-Ku, Tokyo) Angora rabbit fibres were immersed in a solution containing Hg(NO3)2 (1.8%) and HNO3 (3.6%) at 30°C for 30min. After being squeezed they were dried at 95°C for 30min. and aged for 3_??_12 months at 35±1°C, during which the change in their mechanical properties was traced and the following results were obtained: (1) The mechanical properties changed when the aging period became more than three months but the change after 3_??_12 months was statistically negligible. (2) When the carroted fibres were aged after being washed, the aging effect can not be recognized.
For the purpose of practical application of methylation of silk fibers by diazomethane for the improvement of its light-resistance, some checks and improvements of diazomethane synthesis and selection of its slovents were investigated. 1. New method of diazomethane synthesis by Boer and Backer (Recueil, 73 229, 1954) is more favorable than other customary methods in respects of simplicity of preparation, stability of intermediate nitrosomethyl compound and the yield of diazomethane. 2. By some modifications to the Boer and Backer's method, as the common solvent for generation and adsorption of diazomethane, the employment of acetone in place of ether is possible, keeping good yield and safety of the operation like in the ether solvent. 3. In anhydrous acetone, diazomethane is more stable than in the other usual solvents (ether, methanol, chloroform, carbontetrachloride etc.) and the methylation of silk in the acetone solution is carried out satisfactorily as well as in the ether solution.
The diffusion coefficients of purified dye acids of three acid dyes (C. 1. 176, C. 1. 182 and C. 1. 184) in Amilan were determined by the two methods, i. e. the use of Hill's equation and the microscopic measurement of the distance of dye penetration, and the limit of application of these methods are discussed. The diffusion coefficients of these dyes in the unstretched fibre are all about ten times as large as those of the stretched fibre, and it appears that the differences in the fine structure of fibre greatly affects diffusion coefficient. With increasing sulphanation, the diffusion coefficient of acid dye in Amilan decreases, while the activation energy of diffusion increases. The authors have derived the simple equation which is able to give the time of half dyeing for Amilan in terms of the diffusion coefficient and the denier of filament. The equation is: