Padding process

See Dyes, application and evaluation for a discussion of exhaust dyeing, textile printing, and the various pad processes. 

If a padding process is used to brighten a polyester/cotton blend, both the disperse and anionic brighteners may be applied from the same pad bath, even when a resin finish is applied simultaneously to the cellulosic component of the blend. Similarly, both types of... 

Another source of highly colored dyebaths is found in continuous dyeing processes where the last filling of the padder required to complete the process at weU-defined conditions has to be withdrawn at the end of the padding process. Dyestuff concentrations of 50 g technical dyestuff are quite usual for such dye liquors. 

Dioxazine Dyes. The synthetic routes (see below) to almost all dioxazines yield products with a symmetrical structure, resulting in at least two reactive anchors. The highly reactive double-anchor dyes are suitable for both the exhaust and the padding processes. Ecological limits for wastewater are satisfied as a result of a high degree of fixation and low salt requirements in the exhaust process, whereby the latter also has a positive influence on leveling. 

In terms of dyeing methods, the economical padding process is favored. In the exhaustion dyeing process, the trend is toward the short-liquor technique. 

Pad Processes. In a continuous or semicontinuous processes, the fabric is first padded with the dye solution. The substantive adsorption of dyes during padding is avoided by employing minimum amounts of pad liquor at ambient temperatures. For even penetration of the dye, the material is then steamed without intermediate drying for 1-3 min in saturated steam (pad steam process ). Alternatively, it is heated to 80-85 °C and rolled up in a closed chamber where it is slowly rotated for 2-8 h (pad roll process). 

Additional benefits to be realized from the low wet pick-up foam application method include greater line speed (especially where the dryer represents a bottleneck in the pad process to be replaced), lower pollution abatement costs due to reduced volumes of effluent and exhaust gases and reduced water consunption. 

A cotton fabric is to be treated with 5.0 % on weight of fabric (owf) with a chemical finish in a wet on dry padding process. If the wet pickup is 90 %, what concentration of chemical is needed ... 

Figure 5 Metal Thickness Difference vs. Trench width for different pad-process combinations Figure 6 Metal Thickness Difference vs. Trench Width for two different slurries...

The use of vat dyes in pigment form for cheeses and rayon cakes suggested improved techniques for various continuous and semi-continuous padding methods for the application of vat dyes to piece goods. Most vat dyes are now marketed in forms specially prepared to yield relatively stable dispersions of extremely finely-divided particles required for pigmentation. Fhe earliest and simplest procedure was the so-called pigment-pad process illustrated diagrammatically in Fig. 20.3 Ciba review. No. 120). In this case... 

It is also possible to produce antibacterial woven cotton and polyester fabrics using colloidal silver nanoparticles. Figure 1.14 clearly shows that silver nanoparticles are well-dispersed on the fibre surfaces in each fabric. In this procedure, woven cotton and polyester fabrics were padded through a certain concentration of silver colloids and squeezed to 83 % wet pick-up with a laboratory pad at a constant pressure. Textile fabrics in which the antibacterial activity shows good laundering durability can be easily obtained via the padding process using nanosized silver colloidal solutions. 

Because tooling costs are low, the process is most common in aircraft manufacture and repair, where production runs are short. Also, the rubber pad process works be.st with softer and more easily formed materials such as aluminum. 

The overlying software-based system feeds the CMAC scheme (implemented in hardware) with the properly padded (when needed) input blocks Minput which are parts of the whole message that is intended to be protected for authentication. The padding process is a quite simple process that can be carried out by the software. This does not imply security problems since there is no secrecy or keys information that should be protected at this point. The initial unit part is the hardware component responsible for the conditional bitwise operation xor between the Mi pui and one of the subkeys Ki or K2. 

The coating of the technical polyester fabrics was carried out by a padding process with a lab padder (Mathis). The coated fabrics were tightened on a pin tenter heat setter (Labcoater LTE-S, Mathis) and dried for about 1 h. The drying temperature for the technical polyester fabric was always below 120 °C. 

The SMPU solution prepared was used directly in solution form, and was prepared by mixing 80 g of SMPU solution with IL of water. The process employed was the traditional pad-dty-cure process, whereby the cotton fabric is immersed into the finishing solution on a padding machine (Rapid 354) arrd padded twice between two mbber rollers at a pressme of 3 MPa. After the padding process, the wet pick-up of the fabric was about 75% (based on a completely dry sample). It was subsequently dried at 80°C for two minutes, before being cured at 120°C for three mirmtes. 

Once again, it does appear that this technique, often referred to as the SAA/PAD process, is rarely encountered in industry in general and the aerospace business in particular. 

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