Offset Printing Principle:

① Utilizing the principle of water and oil not mixing: The image and text areas of the printing plate are oleophilic (attract ink) and hydrophobic (repel water), while the blank areas are hydrophilic (attract water) and oleophobic (repel ink).

② The image and text are first transferred to a blanket cylinder, which then transfers the ink to the substrate through an inked roller.

③ The cylinder has oleophilic and hydrophobic properties, enabling it to transfer ink efficiently while limiting the transfer of water. Additionally, the cylinder's elasticity ensures accurate transfer of the image and text under high printing pressure.

Characteristics:

① Capable of multi-color printing with vibrant colors, saturated hues, and minimal impurities and stains.

② Large printing area with a flat finish, suitable for high-quality print works.

③ Widely used, with offset lithography being a common example of offset printing.

 

Relief Printing Principle:

① Printing areas: Raised and ink-adhering; Blank areas: Recessed and non-ink-adhering.

② When paper comes into contact with the plate, the ink from the printing areas transfers to the paper.

Characteristics:

Produced under pressure, resulting in a slightly uneven surface finish.

 

Intaglio Printing Principle:

① The image and text areas on the plate are lower than the blank areas, with varying depths corresponding to the darkness of the image and text layers.

② During printing, ink is applied to the plate, and the ink on the raised areas is wiped away, leaving ink only in the recessed printing areas.

③ A substrate with strong ink absorption is pressed against the plate, transferring the ink from the printing areas to the substrate.

Characteristics:

① Varying depths in the printing areas result in varying ink layer thicknesses, creating a range of tones and shades.

② Images and text are printed with a 45-degree screen.

 

Screen Printing Principle:

① Image and text areas: Open mesh holes; Blank areas: Mesh holes blocked, also known as stencil printing.

② Ink is applied to the screen, and a squeegee presses the ink through the mesh holes in the image and text areas onto the substrate.

Characteristics:

① Simple equipment, easy operation, and low-cost printing and plate-making.

② Highly adaptable, capable of printing on hard or soft, flat, curved, or uneven surfaces.

③ Suitable for single-color printing and multi-color or halftone printing with various inks and coatings.

④ Flexible printing area based on the plate setup, suitable for large products.

 

Principle of Digital Printing:

Any printing method that uses ink, toner, or other dyes directly from a computer or output device can be considered digital printing.

Characteristics:

① Not durable: Digital printing uses toner for vibrant colors but is not suitable for long-term preservation.

② Quick turnaround: Eliminates the need for traditional drying and manual processes.

③ Convenient proofing: More vivid color reproduction but may struggle with uniform large-area solid colors.

④ Increased costs: For orders exceeding 300 pieces, digital printing lacks price advantages compared to offset printing.

⑤ Printing size: Limited to A3 format.

⑥ Personalization: Allows flexible design changes and production of different batches of prints.