Offset printing ink requirements have the following characteristics: 

1 the transparency of the ink must be high. Thin film coating into uniform ink, the requirement of bearing of the monlchamus membrane material background to display more clearly, ink transparency requirements higher. Ink on paper, there are three forms of color: 

1 in the form of solid and dot, dot, field (that is, 100% dot) on the recovery of the sun light as selective absorption and reflection, and presented the color. 

Monochrome dot of parallel and overlapping to show: that is, two independent outlets are tied together or stacked on the paper presented color. 

Overlapping color dot: that is, two kinds of color dot in the paper overlap and display color. Such as yellow and blue when the two colors to overprint shows that green hue. 

2 ink pigment particles require delicate. Especially for the fine print. Calendars, landscapes and so on high precision printing, fine particles of the ink, fine pigment particles to printing out fine printing products. 

3 requires strong color printing ink. Color is an ink color intensity or concentration, for the same color ink, color depends on: 

Dispersion of pigments in the link. The higher the degree of dispersion, the stronger the coloring ability. 

Depend on the content of pigment. The higher the content, the stronger the color. 

4 printing ink with light characteristics. Offset printing ink color under the sun, light with light, by the light ink fade, easy to color as far as possible to the extent slow, outdoor advertising of printing products after the weather most likely to fade. The color is yellow, red two kinds of colors, green, black two kinds of color change color, fade relatively slow some, solve good yellow, red two kinds of color fading, discoloration problem, to improve the quality of printing products is very important. 

5 requirements for offset printing ink color efficiency is high. Efficiency is a comprehensive index of gray and color ink, offset printing ink requires color hue to pure, no color deviation, no noise. 

6 the chemical characteristics of offset printing ink can be stable. Ink color in some chemicals will change, especially the acid, alkali, salt, oxidation agent of pigment in the ink will be a certain chemical reaction, often easy to change color. Therefore, it is required that the offset ink has better chemical stability.