Fastness to alkali

P.Y.155 provides clean, somewhat greenish yellow shades and is characterized by high tinctorial strength, good solvent resistance, and fastness to alkali and acid. 

P.Y.120 has less of an impact on the paint industry. In contrast to the similarly colored P.Y.97, P.Y.120 is fast to overcoating. Moreover, it exhibits noticeably higher durability. White reductions, reduced 1 1 to about 1 5, are approximately as durable as P.Y.151 systems. P.Y.120 is recommended for general industrial finishes, including automotive refinishes, and it is also suitable for use in architectural paints. P.Y.120 is completely fast to alkali. 

P.O.62 is frequently used in the printing inks field to produce lightfast offset and aqueous flexographic inks. Its lightfastness in these media equals step 5 to step 6 on the Blue Scale, depending on the standard depth of shade. The prints are not completely fast to alkali and do not tolerate clear lacquer coatings and sterilization. 

The printing ink industry uses P.Br.25 for all printing methods. The prints show excellent lightfastness. 1/1 to 1/25 SD letterpress proof prints, for instance, equal step 7 to step 6-7 on the Blue Scale. Prints made from P.Br.25 are fast to the DIN 16 524 standard solvent mixture, to paraffin, butter, soap, and acid, but they are not entirely fast to alkali. The products are fast to clear lacquer coatings and may safely be sterilized. The temperature stability is up to 240°C for 10 minutes or 220°C for up to 30 minutes, which makes P.Br.25 a suitable candidate for metal deco printing inks. It is also frequently applied in printing inks for PVC. 

P.R.242 affords a yellowish red shade, referred to as scarlet. It exhibits good to excellent resistance to organic solvents, such as alcohols, esters, ketones, and aliphatic hydrocarbons. The pigment is more soluble in aromatic hydrocarbons. P.R.242, like other members of its class, is fast to alkali and acid. 

P.Y.117 demonstrates good fastness to alkali and acids. It is completely fast to overcoating up to 160°C and heat stable up to 180°C. For a system consisting of P.Y.117 incorporated in a silicone resin paint, the manufacturer listed a temperature stability of up to 300°C for one hour exposure. 

P.R.88 is also used for printing inks. Its red-violet shade is especially used for printing inks which are to be targeted for packaging, posters, and other special purposes. The prints are entirely fast to organic solvents, plasticizers, and packaged goods, such as butter and soap. P.R.88 prints are fast to alkali and acid, heat stable up to 200°C, and fast to sterilization. 

P.V.23 is a favorite shading pigment for use in emulsion paints, where it lends a reddish tinge to Phthalocyanine Blue shades. Excellent weatherfastness makes it a suitable candidate for exterior application in media based on synthetic resin dispersions. The systems are fast to alkali and plaster. 

Prints containing Alkali Blue are not fast to the standard DIN 16524 solvent mixture, but they are fast to acid, paraffin, butter, and other materials. Tested in accordance with normative testing standards (Sec. 1.6.2.2), the prints unexpectedly also show fastness to alkali. It should be noted, however, that at higher alkali concentrations the tinctorial strength of the system declines and the shade becomes duller. This is a result of the fact that the pigment reacts with alkali. 

These acid rhodamines are usually used for silk and wool because they have level dyeing properties and show good fastness to alkali however, they have poor lightfastness. An improved process for manufacturing 3,6-diaminosubstituted xanthenes is reaction of the inner salts of... 

The Violamines are used for wool and silk, and give shades fast to alkalies and light. 

Green, Lime n Term applied to those green pigments which are employed for their fastness to alkali (lime). For a considerable time it consisted of the green produced from green earth but the term is now applied to other types, e.g., reduced Pigment Green B. 

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