Offset printing generally refers to offset printing, which is a kind of lithography. Simply put, offset printing is a printing method that transfers the graphics and text on the printing plate to the substrate with the help of blanket, and blanket is also the existence of blanket. This printing method is named.

Blanket plays an irreplaceable role in printing, for example, it can make up for the unevenness of the substrate surface, make the ink fully transferred, and reduce the transfer of water on the printing plate (see below for the role of water in printing) to the substrate.

The above is just a general concept. What we usually call offset printing now, perhaps in a narrow sense, is a three-roll lithography method (printing plate, blanket and impression), which is called offset printing in southern China.

Extended data

Lithographic printing, also known as offset printing, uses the principle that water and oil are immiscible to coat the printed part with grease, so that the non-printed part can absorb appropriate moisture.

When the layout is inked, the printed part will drain and absorb ink, and the non-printed part will have an anti-ink effect, and then press it? Printed on paper, of course, modern offset printing is a very fast mechanical process.

UV ink selectively absorbs ultraviolet light. Its drying is affected by the total energy radiated by ultraviolet light source and the energy distribution of light with different wavelengths. Under the irradiation of ultraviolet light, the photopolymerization initiator in UV ink absorbs photons with a certain wavelength, and the excitant excites to form free radicals or ions.

Then, through intermolecular energy transfer, the polymerizable prepolymer, photosensitive monomer and other polymers become excited States, resulting in charge transfer conjugates, which are continuously crosslinked, polymerized and solidified into films.

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