The structural changes of cotton fibers by practical liquid ammonia treatment under four different conditions were investigated. Two liquid ammonia units were used, one of which had one drying cylinder and the other had two cylinders. The running speed of each unit was set at high or low. In each unit, the lattice type I did not decrease even after long ammonia wetting, and as the drying time increased, the lattice typeIII increased, the amorphous region also decreased. Therefore, regarding practical liquid ammonia treatment, the changes in the crystal structure are thought to occur as follows: Almost all cellulose changes to ammonia cellulose after short ammonia wetting, and along with the removal of the ammonia, the lattice type III increases, the amorphous region decreases and the residual ammonia cellulose converts to the lattice type I. It was found that after liquid ammonia treatment the pore volume corresponding to the PEG radius over 1.1nm and the water retention decrease, the dry and wet crease recovery angle, the tear strength, the tensile strength and the dye uptake increase. The degree of decrease or increase depends on the degree of drying respectively.
There are two major methods in liquid ammonia treatment, which are the ammonia dry process and the ammonia wet process. In the ammonia dry process, liquid ammonia is applied on the fabrics and is removed by heating, whereas in the ammonia wet process, the ammonia is removed by water. The differences of the effects between these two processes were investigated precisely using continuous practical units and a discontinuous laboratory unit. The X-ray diffraction patterns of the finished samples were quite different between the two processes: only the cellulose I type was found in the ammonia wet process samples, while both of cellulose I and III types were found in the ammonia dry process. Pore distribution analysis by liquid chromatography also showed different results between the two processes. Various other properties though were not substantially different. The slight differences found were as follows: the higher crease recovery angle in the ammonia dry process, and the harder hand and the higher dyeabillity in the ammonia wet process.
The eight kinds of standard fabric, cotton, nylon, acetate, wool, rayon, acryl, silk and polyester, were treated with the extract of Aloe arborescens (Kidachi aloe) dry leaves under an alkaline condition, respectively. Among them, the treated silk, wool and rayon fabrics showed deep colors, and moreover, the silk and rayon ones had strong antibacterial activity. They were tested on their color fastness against ultraviolet, washing, water, dry-cleaning or dry-heating, and then, their antibacterial activity was inspected again. As a result, it was cleared that the treated silk fabric keeps more effective antibacterial activity than the rayon one after the color fastness tests. In addition, it was found that its antibacterial activity was more effective on Staphylococcus aureus than on Klebsiella pneumonoiae. For silk, the extract of Aloe arborescens dry leaves was suggestted to have a possibility as a practical antibacterial agent.
It is commonly known that water repellency of the fabric treated with fluorocarbon resin brings about a decrease by the washing and recovers by the subsequent heat treatment. In this article, effect of the water repellency was investigated on the cotton and polyester fabrics treated with silicone resin. Silicone resin has been widely used in the textile finishing as the softening and water proofing agents. The fabrics were treated with a silicone resin, Poron MR (Shinetsu Chemical Co.) and then washed and subsequently heat treated. Although the water repellency increased by the resin treatment, it decreased by the washing apparently and recovered a little by the heat treatment. The effect of the heat treatment was small comparing with that of the fluorocarbon resin. Furthermore, in order to investigate the change of the surface chemical composition of the fabric, ESCA analysis was carried out. The O1s and Si2p intensities were almost unchanged by the washing and following heat treatment. The Si2p showed also the same tendency. As a mechanical property of the treated fabric, KES shearing and bending hysteresis parameters, modulus and hysteresis width of the silicone resin treated cotton and polyester fabrics decreased by the heat treatment after washing. Therefore, the treatment is effective at improving the softening of the fabric in water repellent finish.