Insoluble azo dyes known to the high color, bright color, especially red, purple, blue, dark reddish brown. The light fastness of dyeing concentration, pale when poor. Rubbing fastness is also low. Printable Black And White Checkered Flag Chlorine bleaching of most of the dyes and high fastness to washing.
(A) Naphthol and its backing of those who used to produce insoluble azo dyes and diazo compounds of the chromophore coupling of phenolic coupling agent known as Naphthol. The majority of the naphthol naphthol derivatives, currently the most used
Naphthol can not be directly dissolved in water, Printable Black And White Checkered Flag but must be the formation of the naphthol sodium salt was only dissolved in caustic soda solution. Personalized Decorative House Flags Dissolve the caustic soda dosage should be used when more than the theoretical amount, which is to inhibit the hydrolysis of the sodium salt of Naphthol and the prevention of the role of carbon dioxide and acid gases in the air. However, the amount of caustic soda should not be too high, otherwise it will reduce the naphthol dye to reduce the color yield. In addition, the color Shihai likely to cause decomposition of the diazonium salt. Therefore, caustic soda, the actual amount of control in the free base volume for 3 ~
Naphthol fiber dyeing process known as rendering. The base fluid composition is as follows (pad):
Naphthol the AS
Pacific oil 10ml
Caustic soda (360Be) 13ml
Heated water into a
Naphthol dissolved with hot melt and cold dissolution method, commonly used in hot melt method. The thermosol
The Naphthol bottoming process conditions vary with the staining method, the base temperature in the general dip of 30 to
(B) of the chromophore and its diazotization color base is generally organic aromatic amines, Printable Black And White Checkered Flag it can not be directly coupled chromogenic and Naphthol must be at low temperatures by diazotization with sodium nitrite and hydrochloric acid can color phenol coupling color. Therefore, Advertising Feather Flags And Banners the diazotization reaction is the effect of sodium nitrite and hydrochloric acid, the amino groups on the color-based molecules into the diazo reaction process:
Ar-NH2 2HCl NaNO
Diazotization method has two kinds of cis and inverse method.
Smoothing is the color base before adding the appropriate amount of water blending, then add the specified amount of hydrochloric acid, low temperature and under constant stirring, slowly add sodium nitrite, diazotization reaction to complete. Color-based red color base orange GC base purple color sauce GBC can be used along
Diazotization of the inverse method is the tone color base with sodium nitrite and an appropriate amount of cold water into a uniform paste and ice cooling, and then slowly pour it into the continuously stirred ice-hydrochloric acid solution, the reaction is completed, the base color red B is the inverse method diazotization.
Color based diazotization solution stability related to the dyeing quality problems. Wind Flags Wholesale When the diazotization reaction, the diazonium solution was transparent liquid, Custom Made Swooper Flags When the diazotization reaction is not complete, the solution becomes cloudy. In order to ensure the stability of the diazotization solution, Printable Black And White Checkered Flag the solution should be appropriate to increase the amount of hydrochloric acid, it showed a strong acidic.
Some color diazotization conditions difficult to grasp, Custom Printed Teardrop Flags dye works often be pre-diazotization, and then add the stabilizer, made of the color salt sale, such as the commonly used where the Lamine blue salt VB and other.