Chapter 7 Thermosetting (Heat setting) Lecturer: Prof Dr Yan kelu
Chapter 7 Thermosetting (Heat Setting) Lecturer: Prof. Dr. Yan kelu
7.1 Introduction The dimensional stability, dyeability, and other properties of thermoplastic fibers are affected by repeated heating and cooling The main purposes of heat setting are as follows To stabilize the material to shrinkage distortion, and creasing To improve the dyeability of fabrics
7.1 Introduction • The dimensional stability, dyeability, and other properties of thermoplastic fibers are affected by repeated heating and cooling. The main purposes of heat setting are as follows: • To stabilize the material to shrinkage, distortion, and creasing, • To improve the dyeability of fabrics
定型三大内容: 棉的丝光 ·合纤热定型 树脂整理
定型三大内容： • 棉的丝光 • 合纤热定型 • 树脂整理
合成纤维在纺丝成型中热处理时间较短, 存在内应力;在织造过程中纤维、纱线 受力也存在内应力。因此,合纤织物遇 热易发生皱缩,织物幅面失去平整,印 花花纹改变,成衣尺寸失去稳定性 定型的目的 消除织物上已有的皱痕和提高织物的热 稳定性(主要指高温条件下的不收缩性) 和不易产生难以去除的折痕
• 合成纤维在纺丝成型中热处理时间较短， 存在内应力；在织造过程中纤维、纱线 受力也存在内应力。因此，合纤织物遇 热易发生皱缩，织物幅面失去平整，印 花花纹改变，成衣尺寸失去稳定性。 • 定型的目的： • 消除织物上已有的皱痕和提高织物的热 稳定性（主要指高温条件下的不收缩性） 和不易产生难以去除的折痕
fiber demanded y arn available modal ware stable
• fiber demanded • yarn available modality • ware stable
7.2 General Situation of Processing Heat setting can be done with either dry or steam. Polyester is usually heat set dry while nylon may be heat set either dry or with steam. Continuous heat setting of flat fabrics is usually done with dry heat by impinging hot air on the fabric in a tenter frame. Steam heat setting is often done in an autoclave or may be done using continuous steaming equipment
7.2 General Situation of Processing • Heat setting can be done with either dry or steam. Polyester is usually heat set dry while nylon may be heat set either dry or with steam. Continuous heat setting of flat fabrics is usually done with dry heat by impinging hot air on the fabric in a tenter frame. Steam heat setting is often done in an autoclave or may be done using continuous steaming equipment
7. 2. 1 Dry setting machine and process 7.2.1. I Dry setting machine see also Abb.7.290, p. 184 Pig 7-1, and Montex
7.2.1 Dry setting machine and process 7.2.1.1 Dry setting machine see also Abb.7.290, p. 184 Pig.7-1, and Montex
7.2.1.2 Process width: 2-3 cm bigger than finished size overfeed: 30%(Cloth feeding device Temperature and time: see also P453 Tab. 31 doffing(cropping) <50 oC(cold air; cooling cylinder)
7.2.1.2 Process • width: 2-3 cm bigger than finished size • overfeed : 30% (Cloth feeding device) • Temperature and time : see also P.453 Tab.31. • doffing(cropping): < 50 oC(cold air; cooling cylinder)
7.2.2 Wet setting Saturated steam The presence of water apparently promotes molecular chain rearrangements which increase the size of openings through which dyes can diffuse
7.2.2 Wet setting • Saturated steam • The presence of water apparently promotes molecular chain rearrangements which increase the size of openings through which dyes can diffuse
7.2.3 Arraignment of Working Procedure Heat setting can be done before any wet treatment after scouring and mercerizing or after dyeing of the fabric
7.2.3 Arraignment of Working Procedure • Heat setting can be done: • before any wet treatment, • after scouring and mercerizing, • or after dyeing of the fabric