The effect of hemicellulose contents in pulp on beating rate and strength of paper made from it was studied. In this study two methods were used, one the adding method (adding isolated hemicellulose to the standard pulp) and the other the extracting method (removing hemicellulose stepwisely). In the former when the hemicellulose is isolated with drastic agents, chemical nature of hemicellulose is liable to change, so that it is impossible to say that the isolated hemicellulose will act in the same manner as it does in the original state. Therefore extracting method was employed in the present research. For the preparation of chlorite holocellulose, thin pieces of beech and aspen wood were treated with hot acidified sodium chlorite. These chlorite holocelluloses were treated with KOH solution under nitrogen gas, in order to minimize the oxidation of cellulose. For hemicellulose extraction, KOH solutions of various concentration (from 0.3 to 20%) were used in order to get a series of pulp in which the hemicellulose content was stepwisely arranged. The beating rate and the sheet strength of this series of pulp were examined. From the result of this study, it was concluded that there appeared to be the optimum hemicellulose content in pulp as for as the paper strength was concerned. Other observations were also made with regard to the result observed.
The difference between the ideal contractive force of a multifilament with circular section and the observed value of corresponding monofilament by twisting at a fixed length may be explained by the fineness of the fiber included in the multifilament. If the denier of the monofilament is known, the number of corresponding multifilament of various denier of fiber can be calculated by the following formula._??_ where R; Diameter of multifilament equal to the cross section of Amilan or Saran under consideration. r; Diameter of fiber included in these multifilament. n; Number of fiber. The curve between contractive force at break of these multifilament by twist under a fixed length and their denier of fiber are shown in Figs 4 & 5. From these curves and observed values, we can estimate the fineness of fiber (Fibrill) for Amilan (890 D); Saran (1146 D) which correspond respectively to 3 d, 18 d. Especially for Saran, the fineness of fiber 18 d (Fibrill) is ascertained by microscopic observation.
Findings of theoretical and experimental researches on the winding yarn cnrves around the weft pirns are reported. The displacement Z of the contact point between yarn and pirn or yarn layer surface along the pirn's central axis is calculated by the following equation; where, form of pirn or yarn layer is cylindrical, spindle, revolving speed is constant and traversing motion of yarn guide is expressed by A (1-cosKw). w: revolving angle of the spindle r: radius of the cylindrical pirn or yarn layer d: distance between the pirn or yarn layer surface and traversing yarn guide A: amplitude of a traverse K: speed ratio between the traverse motion and spindle revolution If the pirn or yarn layer is conical form; where r: mean radius of the pirn or yarn layer In the equations (1) and (2) above, the first term expreses the traverse motion and the second term expreses the deflection between the yarn motion around the pirn and the yarn guide motion. It is noted that the focuses of the weft yarn curves around the pirn obtainied by the experimental method almost coincide with the calculation by the equations (1) & (2), and the larger d and K are the large becomes the deflection between the yarn motion around the pirn and the yarn guide motion.
The authors continued the experimental study to improve the ring part and to simplify the test procedure. The results are briefly reported as follows: 1. Instead of hard-chrome plated steel ring, rubber rings of the same size were put to test in anticipation of obtaining more reasonable and practical results, because of its softness and elastic properties resembling those of human fingers. But the rubber ring gave neither such desired results nor any feasable outcome. 2. For the purpose of obtaining a simpler expression of withdrawal resistance without troublesome calculations, the authors used an idea of “mean withdrawal resistance per unit sectional area.” mean with drawal resistance per unit sectional area Fm/A≡fm where Fm: mean withdrawal resistance over a range of fullness from 0 to x, x_??_1.0 A: sectional area of ring hole. In a range of fullness up to 1.0, the value of fm practically coninside with the result calculated from the experimental formula, αρβ, in the previous report. 3. A trial to obtain values of fm that would coninsided of various diameter of ring holes by using a series of ring holes of similar dimensions, ended in a failure. In this case also, the same test piece gives different values of fm if tested by rings of different diameter.
Dye accessibility of fiber depends on the magnitudes of the following factors: 1. The surface area through which the dye passes into the fiber. 2. The speed by which the dye migrates in the fiber. 3. The inner volume υ (cc. per lg dry fiber) in which the dye exists. 4. The dissociation energy E of the dye-fiber-complex. As (1) and (2) can be calculable when E is known, the author starts the studies from obtainingE. When in the hot and very dilute direct dye solution the sizes of the dye particles are very small and homgeneous, there holds the next relation. (dissociation energy of a dye particle from the dyed fiber) (cal/ particle) Here k: Boltzmann's constant, T: absolute temperature, m0: number of dye particles in the initial dye bath, m: number of dye particles in the equilibrium reaching dye bath, υ: volume of the dye bath. The dyeing experiments are as follows. Materials to be dyed; viscose rayon, cuprammonium rayon, Vinylon (appolyvinylformal fiber), and polyvinylalcohol fiber. Temperature: 80°C Period: 3 hrs. Liquor ratio: 1/250. Dyes: Benzopurpurine 4BKX Chrysophenine NS Naphthamine Blue 12B (all purified). Dye concentration: 0.001%(Wt) (Benzopurpurine 0.003%) NaCl concentration: 0.001%(Wt) (Benzopurpurine 0.0003%) The results are: Under the same dyeing condition E of Vinylon is found to be greater than that of cellulose fiber. but smaller than that of polyvinylalcohol fiber.