Colour rinses

Semipermanent dyes are formulations that dye the hair without the use of hydrogen peroxide, to a colour that only persists for 4-6 shampooings. Temporary hair dyes or colour rinses aim to provide colour that is removed after the first shampooing process. 

Personal care products Leave-on rinse-off cosmetics toiletries Colour cosmetics, hair care, baby infant care Skin creams / lotions, wet-wipes, sun-care Bath shower gels, hand body wash, soaps... 

Fig. 28. Valence band spectra (UPS) of an AIROF electrode in the coloured (1.25 V) and in the bleached (0.0 V) state. The electrode was rinsed after emersion with ultra pure H20. After [67],...

Figure 12.26 Effect of temperature and pH of rinsing on the colour yield of dyeings of Cl Vat Orange 9 [247]...

A 1-50 g mass of aspirin was hydrolysed with 25-0 cm of 1-00 mol NaOH solution. After the hydrolysis was complete, the reaction mixture was transferred, with rinsings, to a 250 cm standard flask and made up to the graduation mark with distilled water. The solution was mixed thoroughly and 25-0 cm was pipetted Into a conical flask, along with a few drops of phenolphthalein Indicator. This was titrated with 0-0500 mol sulfuric add solution until the end-point of the titration was Indicated by the colour change from pink to colourless. The titrations were repeated until concordant results were obtained. 

Effect of Light on the Decomposition of Silver Chloride. Introduce 2 ml of a 0.1 W silver nitrate solution into a test tube and add dropwise such an amount of a saturated sodium chloride solution that will be sufficient for the complete precipitation of the silver as -a chloride. Rapidly filter out the precipitate, rinse it with water and put it on two watch glasses. Place one glass with the precipitate in a dark cupboard, and leave the other at a window in daylight. In an hour, compare the colour of the precipitates and explain the phenom->ena you observe. How does light affect the reaction After the experiment, put the precipitates containing a silver compound into he jars set aside for them. 

Open the stopper of flask 7 and watch the change in the colour of the gas. Again add 2-3 ml of water, rinse the flask, and pour out the liquid into a beaker. Prove that a solution of sulphuric acid has been prepared. What impurities does the acid contain Write the equations of all the occurring processes. 

Bleaching. It is often necessary in the manufacture of lacquer nitrocellulose to remove all traces of coloured substances by bleaching. One method consists in oxidizing with potassium permanganate in the proportion of 1 kg KMn04 to 100 kg of lacquer nitrocellulose in the presence of a little sulphuric acid. After the reaction is over the nitrocellulose is rinsed with water, and the brown colour of manganese dioxide is removed by the action of sulphur dioxide or sodium sulphite. 

A certain quantity of the spirit (e.g., 300 c.c.), together with the rinsings of the measuring vessel, is distilled with a few drops of sodium hydroxide solution or a little magnesium oxide to remove the fixed matters aud the colouring materials and to liberate the pyridine bases in case these are present partly as salts the amount of distillate collected is that of the spirit taken. 

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