In comparison to acetylation of cotton, ramie yarn was acetylated with acetic anhydride using sulfoacetic acid catalyst and benzene diluent.
Ramie requires a somewhat longer time of pretreatment (immersion in acetic acid). When appropriately pretreated, the rate of acetylation and chloroform solubility of the acetylated yarn are similar to that of cotton, but the shrinkage by the acetylation is in this case much smaller. Acetylated ramie may be dyed evenly. No serious loss of the standard and knot strength was to be observed by the acetylation. Elastic recovery of highly acetylated ramie is excellent.

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Cellulose fibers may be acetylated smoothly without imbibition liquid but with impregnated solid. The solid must be of such compounds that has affinity for acetic anhydride and introduces this into the fiber. Besides compounds which had been mentioned by J. J. Thomas there are other compounds which are effective. Single catalyst may also be applied for this purpose.

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As cyclohexanone is insoluble in water, acetalization of polyvinyl alcohol fiber with emulsion was undertaken
Nonionic emulsifier, such as polyethylene glycole laulylether, give good emulsion and are stable even in acid medium.
Although acetalization takes place smoothly, it is defficult, as in methanol solution, to obtain higher degree of acetalization than 30 mol%.
There the acetalized fibers are non-resistent to boiling water.

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The determination of acetyl value in cellulose acetate by Eberstadt method is a time-consuming procedure that does not lend itself well to control the routine operation in industry, although it is now used as the most aconrate method.
The determination of cellulose content in cellulose acetate was easily carried out by applying the bichromate oxidation method for cellulose in cotton.
This procedure, with some improvement, is found particulary rapid and also gives exact results.
The standard deviation and the accuracy of the Eberstadt method and our modified method are discussed by comparison.

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In order to investigate the behaviors of mercerized cellulose in a course of emulsion xanthation, linter and rayon wood pulps and their mercerised pulps were emulsion xanthated under the conditions that merecrized pulps would show the most peculiar behaviors in the reaction. The solubilities of pulp, γ-values of undissolved part of pulp and viscose were determined at various reaction times.
The findings (Fig. 1_??_14) on the bebaviors of four kinds of pulps are discussed.

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In actual slivers, there are groups (“Cluster”) of fibers which cannot be divided into single fibers in carding and behave like a single fiber. In the drafting zone, moreover, some of these groups (of fibers) may be divided into several smaller groups and some of groups or fibers may be united into a single group. In this paper, the effects of grouping of fibers and its division or combination in the drafting zone upon the irregularity of drafted sliver are studied. After theoretical studies, the following equations may be introduced. Here, V₀(y, ∞) and V(y, ∞)are the relative variances of the number of fiber leading ends included in a piece of sliver y long, in in-going and drafted sliver respectively. D is the draft ratio, and _??_ is the mean density of fiber leading end in in-going sliver. K is the number of fibers which combine into a single group, _??_₀ and _??_ are the means of K, and C²₀_??_K_??_and C²_??_K_??_are the relative variances of K in in-going and drafted sliver respectively. ατ is the relative amplitude of variation with wave length λτ in in-going sliver, which may be analysed into Fourier Series. I(y), A(λτ, D, σ) and α(λτ, D, y) are coefficients which vary with D, λτ, y and the shape of distribution of velocity change point of fiber leading end, as formulated in the previous paper. From these equations, several problems on actual drafting may be discussed.

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In this paper, we deal with that phenomenon similar to buckling when textile fabrics are deformed by shearing.
When the shearing deformation of textile fabrics approach a certain value, the stress concentrates along their diagonal line, and some nodal-lines appear on them. This critical deformation may be called the critical angle. This angle can he obtained indirectly from an discontinued point on the load-deformation curve.
From our experiment the following observations may be derived:
(1) The critical angle of sized textile fabrics are smaller than that of the scoured.
(2) The relationship between the tension applied to textile fabrics and the critical angle is linear on the semi-logarithmic co-ordinates, and the tangent is nearly constant independently of their cover factor.
(3) The degree of freedom from the shearing deformation of textile fabrics are inversely proportional to their tightness.

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The felting process is generally carried out in aqueous solution or steam, because the rate of felting in aqueous solution is larger than that in the air. So the difference of the cyclic compression-recoveay behaviours of the bulks of two sorts of Angora rabbit fibres were observed in the water and air by means of the method described in the preceding paper.
As the results, it was recognized, the specific thickness t (cm/g•cm^-2) under a certain pressure p decreased as the number of cyclic compression increased in the distilled water, but in the air it slightly decreased. The slope of the compression line (log t-log p) varied according to the sorts of the fibres in the bulk.

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In order to size effectively to warp yarn with starch at low temperature, starch size solutions with low viscosities were prepared by decomposing starch molecules with α-amylase, and observations are made on the mechanism of addition of starch size to yarn, mechanical properties of starch films and sized yarn, and their relations, with the following results obtained:
a) Drop of viscosity of size solution based on decomposition of starch molecules with α-amylase was remarkable, and its dependency on temperature was less in proportion to the degree of decomposition. Viscosity of starch solution illustrated the saturated minimum value after the time of treatment correspond to the addedamount of α-amylase to starch.
b) In decomposing starch, it is better to add α-amylase to starch solution after preparing its size solution, for the reason of obtaining homogeneous size solution. Similarly, it is better to treat starch for longer time with smaller volume of enzyme than treatment for shorter time with larger volume.
c) Reduction of viscosity by enzyme treatment promotes penetration of size solution into the yarn, and it results in increased amount of size adheres to the yarn.
d) Increase of breaking strength and abrasive resistance of sized yarn per unit weight of adhered size is remarkable using the size treated with α-amylase. It may be explained from difference of role between size fixed on surface of yarn which resists mainly to stretch and the inter-fiber size which takes part of cross-links between them.
e) As decomposition of starch is advanced mechanical properties of sized yarn gradually deteriorates, but they are much more predominant than in that sized with non-treated starch. All this is due to weakning of mechanical properties of solid phase of fixed size prepared by drying, based on decomposition of starch molecules with α-amylase. It can also be verified by determination of breaking strength and elongation of films made with starch sizes variously decomposed by α-amylase.
f) From above results, it is obvious that the analytical method is more desiable to perform extensive study of warp sizing than by determination only of mechanical properties of sized yarn.

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This paper deals with the creep phenomenon displayed by resin-treated viscose rayon. Such viscoelastic behavior of these rayon fibers are shown here as creep curves that indicates the state of interiors of fibers affected by chemical bonding or phisical adhesion among cellulose chains.
It was found that elongation (%) of treated fibers was generally smaller than of non-treated fibers at all ranges of time, and maximum point of distribution curves of retarded times in treated fibers depends less on loads than in non-treated fibers.

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A spun rayon fabric, pretreated with ferrous sulfate, was dipped in an aqueous acrylic acid solution containing a little H₂O₂, then wrung and heated at 90_??_95°C for polymerization. Next it was treated by aluminium acetate solution to reduce hydrophilic property.
We studied some properties of treated fabric and obtained following results.
1. Acrylic acid monomer can be polymerized in viscose fibre.
2. Acrylic acid monomer impregnated and polymerized fabrics can resist to soaping by treating with aluminium acetate solution.
3. By above treatments some improvements in character of fabrics may be expected, i.e. rigidity, crease recovery, water repellency, shrinkage in soaping and strength of spun rayon fabric.

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