ANALYSIS OF ROLLING ON THE EDGES OF AN ASSEMBLY DOUBLED USING THERMOFUSION

• Main Author: PORAV Viorica
• Format: Article
• Language: English
• Published: Editura Universităţii din Oradea 2020-05-01
• Series: Annals of the University of Oradea: Fascicle of Textiles, Leatherwork
• Subjects: contraction percentage; humidothermal treatment; thermofusing; chemicalized insert; twisting; flaking; differential contraction
• Online Access: http://textile.webhost.uoradea.ro/Annals/Vol%2021-no%201-2020/Textile/Art.%20no.%20412%20pag%2093-96.pdf

In this paper we analyze an undesirable effect that appeared as a result of the thermal or humidothermal thermofusion operation, due to the incorrect choice and use of the thermofusion parameters, the angle of overlap of the warp threads of the two materials (in the case of a chemicalized weaved insertion), or, most commonly, due to the incompatibility of the shrinkage percentage of the chemicalized insertion with the percentage of shrinkage of the base material. Thus, a twisting effect of the edges of the assembly, consisting of the base material and the insert with adhesive, may appear (especially for fused parts with a small surface). The twisting edge may be towards the chemicalized insert, in this case being considered positive, when the percentage of shrinkage is greater in the insert, and can be considered negative when the twisting is towards the base material, when this has a contraction rate higher than the insertion. In fused assemblies - base material and adhesive chemicalized insert - with large surfaces, the difference between the contraction percentage of the coated insert and the base material manifests itself in the form of bubbles, which can be observed better during rolling or handling of the material while performing certain work operations. In contrast to fused assemblies with small surfaces, for which the difference in the percentage of contraction is observed immediately, for fused assemblies with large surfaces, this difference is observed during manipulations in technological processing, during wearing, or after cleaning.