Hybrid composites were prepared by impregnating epoxy resin into the short fiber mat consisting of carbon and glass fibers. The effect of the mix ratio of the reinforcing fibers (hybrid ratio) on the mechanical properties of the hybrid composites and the temperature dependence of the mechanical properties were studied.
As the hybrid ratio of carbon fibers decreases, Young's modulus decreases almost linearly, the tensile strength remains almost constant, and the impact fracture energy increases almost linearly. It is possible to estimate Young's modulus, the tensile strength, and the impact fracture energy of the composites with various hybrid ratios from an additive rule.
Young's modulus and tensile strength decreases with increasing temperature. The impact fracture energy increases as the temperature rises. The hybrid ratio-temperature superposition holds for each mechanical property.

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The flow of polymer melt in a flat die was analyzed theoretically by using a computer simulation and the relationship between the theoretical and experimental results was investigated.
As for the pressure drop in the die, the theoretical results agreed with the experimental ones for different kinds of dies. But with respect to the residence time distribution of polymer melt in the die, especially in case of coat-hunger type die, the theoretical results were slightly different from the experimental ones near the edge of die. As the uniformity of polymer melt depends on die lip clearance, the exact correspondence between theoretical and experimental results could not be obtained. But the theoretical analysis is very useful to evaluate the uniformity of a flat die.
By using the theoretical equations and dimensionless analysis, the scale-up rule considering the pressure distribution, residence time distribution and uniformity index was presented. We can obtain a basic consideration for design of a flat die by means of computer simulation technique, and the experimental results of both smaller flat die and the scale-up rule can be used for efficient design of larger flat die.

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In an attempt to obtain disulfide-enriched wool (fibers and fabrics), the reaction of wool with a disulfide-containing crosslinking agent, that is, bis (β-isocyanatoethyl) disulfide (BIED), was studied in dimethylformamide. BIED reacted mono-and bifunctionally with wool to form branches and crosslinks, respectively. The crosslinking efficiencies in the percent ratio of the number of the crosslinks (inter-and intrachenic) formed to the total disulfide introduced, which were obtained before and after reduction, ranged from 48% to 66%. The crosslink density of a BIED-treated fiber sample was determined by the method of Arai and Hanyu from Young's modulus in aqueous LiBr/butyl carbitol at 70°C. The crosslink density of the sample determined by the chemical analysis was 1.4 times that of the control wool, while the density determined from the physical method was two times. Supercontraction behavior of BIED-treated wool fibers was compared with that of hexamethylene diisocyanate-treated fibers in either an aqueous solution of NaHSO₃, a disulfide reducing agent, or in formamide, a hydrogen bond breaking reagent. Hexamethylene diisocyanatetreated wool fibers did not supercontract in both media, while BIED-treated wool fibers with a low add-on supercontracted in aqueous NaHSO₃ but did not in formamide. BIED-treated wool fibers with a higher add-on, however, did not supercontract in aqueous NaHSO₃, probably because the excessive introduction of hydrophobic new crosslinks interferes with the penetration of the reducing agent.

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The dyeing rates of wool fibers pretreated with t-butanol-n-heptane, formic acid, chloroform/methanol and aqueous n-propanol were investigated with reference to changes in the fine structure of wool fibers. The dyeing experiments were performed using C. I. Acid Orange 7 and Acid Red 73 in an acidic dyebath. An acceleration of the rate of dyeing by the solvent treatment was observed: the apparent dyeing rate increased in the following order; uncleaned (scourd) wool<cleaned (t-butanol-n-heptane treated) wool<formic acid treated wool=chloroform/methanol treated wool<aqueous n-propanol treated wool. From the relationship between the relative dye uptake (C_t/C∞) and the square root of the dyeing time (t^1/2), it can be seen that the surface lipid-type contaminants act as a factor interfering with the dye penetration. Further, it is apparent that the solvent treatments to extract lipid and protein materials facilitate the dye penetration within the bulk phase, Since the activation energy for the dye diffusion was the same for all the pretreated wool fibers, the diffusion mechanism of dye molecule within the bulk phase for all the solvent-extracted wools assumed to be nearly the same as that for the cleaned wool.
Accordingly, the increase of the apparent dyeing rate is attributable to 1) the reduction of surface barrier effect and 2) faster movement of dye molecules within the cell membrane complex (CMC) and an increase of the effective internal surface area for dye penetration caused by the modification of bulk structure in the CMC.

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We designed a data structure for paper pattern that enables to describe how the fragments or parts of a dress are sewed together and how the dress is put on the body. Such information is required in our system for 3-dimensional CAD for dress. In this system, we input the shape of each fragment, assign the lines to be sewn and mark some lines which are to put at some characteristic position of the body (e. g., waist line). Then the computer divides the fragments into finite elements, establishes the topology of the dress by referring the sewing information, estimates the rough position of each element (i.e., put on the body), calculates the form and distortion of the dress from mechanical characteristics of the cloth and body shape data, and displays the solid view of the result on 3-dimensional graphic display. The fact that our CAD system can simulate the formation of the final shape of the dress, assures that the information given in our paper pattern suffices to indicate how the parts should be assembled and sewn in CAM or automated sewing system. In this paper we describe the data structure of the paper pattern and the automatical division of it into finite elements.
A pattern of a dress usually consists of some pieces of cloth which are to be sewn together, and each piece has rather complicated boundary curves. Even though the lines which will be sewn together have different shapes and lengths, our program generates the points correctly corresponding with each other on every line. Moreover, when the shape of a line is complicated, the pitch of division is automatically reduced so that the line defined by the calculated dividing points well approximates the original line. Then every fragment is divided into a collection of triangles (formally, into a two dimensional simplicial complex).
Our program can divide an arbitrary pattern and can produce well formed triangles, even if there is no additional information for division instructed by the user. Hence, it is suited for the use by those who are not expert with the mechanical analysis by finite element method.

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An attempt has been made to determine the solubility parameter by solubility method of disperse dyes in single and mixed solvents whose solubility parameter values have been known. The solubility parameters of the dyes were also calculated using Hoy's and Small's methods. Furthermore, the relationship between the solubility parameters of the dyes and the amount of saturation adsorption of the dyes on poly (ethylene terephthalate) films was investigated. When the dyes are applied on poly (ethylene terephthalate) films from an aqueous dispersion, the correlation between the solubility parameter values determined by solubility method and the dye adsorptions is closer than that between the values calculated using Hoy's and Small's methods and the dye adsorptions.

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This is a paper concerned with investigating and discussing how the specialists' or consumers' groups perceive the color names and color differences of pile fabrics.
The results obtained are as follows.
(1) Specialists assigned most of color names to the colorimetric ones, but those perceived by consumers did not agree well with the colorimetric ones. A long term training for the specialists in the color recognition results in the exact recognition of the surface colors of pile fabrics and in the proper assignments of the color name. On the other hand, consumers do not realize the correct meanings of the tone adjectives for the lack of experience.
(2) The color names perceived by specialists and consumers by the use of the standard color chips corresponded well to the colorimetric ones.
(3) The correlation coefficient between the color differences perceived by specialists and the colorimetric ones was very high, but the coefficient for the consumers' was low. This fact also indicates as that specialists have established the standard colors for the judgement of color differences by a long term experience on the color differences.

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“Wicking” of water was examined with cotton and polyester fabrics.
It was found that the hight of absorbed water increased with increasing twists, but decreased when excessively twisted. It was explained that water was absorbed mainly through the capillaries formed in the threads and the diameter of the capillary was influenced by the amount of twist. The hydrophobic fibers as polyester do not always show lower values compared with hydrophilic fibers as cotton.

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