Special types of damage and their analysis

As a supplement to damage analysis in relation to specific fibres this section deals with important types of causes of damage. Mahall divided his book entirely on the basis of types of damage, namely  

Since these deposits are usually not distributed evenly on the fibres and textile 

Even more sensitive than these staining tests for detecting grease and oil contamination is an imprint on thermoplastic films (see Section 8.4.6). During production of the imprint, hydrophobic deposits diffuse into the film and can usually be easily recognized by the local cloudiness they cause. The natural waxes of cotton do not interfere here because they are evenly distributed. Spots caused by pigments or disperse dyes are also transferred onto the film imprints and are then easier to investigate microscopically.  

In addition, grease, oil, waxes and paraffins can be detected by IR spectroscopy, either by a direct comparison of spectra from the stain and from unstained areas, with the possibility of subsequent subtraction of spectra, or after extractions and concentration by spectroscopy of the extraction residue. 

The high frequency of stains as a manifestation of damage was mentioned in Section 8.3.2. The reasons for the occurrence of stains are very numerous. Several examples of stain analysis were described in Section 8.4.4 and the typical method of approach in Section 8.3.5. LoffeT has also described the comparative selective extraction of stains with subsequent identification, preferentially with TLC and IRS. In Section 8.4.3 details of TLC analysis of stains caused by grease and oil or polyester carriers are presented. In Section 8.4.4 information is given on the identification of silicone stains and fluorocarbon deposits using IRS. The detection of silicones with fluorescence microscopy is described in the literature.  

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