Reducers are additives used in screen printing inks to adjust the viscosity or thickness of the ink. Reducers are typically added to the ink to make it easier to work with and achieve the desired printing results. There are different types of reducers, such as:

1. Viscosity Reducers: Viscosity reducers are used to thin out the ink and make it flow more smoothly through the screen mesh onto the substrate. This helps prevent clogging of the screen and allows for more consistent printing results.

2. Retarders: Retarders are used to slow down the drying time of the ink, especially in hot or dry conditions, to prevent the ink from drying out too quickly and causing issues during the printing process.

3. Curable Reducers: Curable reducers are used in plastisol inks to reduce the ink viscosity while still allowing the ink to cure properly when exposed to heat. This ensures that the printed design remains durable and long-lasting.

Reducers are essential tools for screen printers to control the ink's consistency, drying time, and overall performance. Properly using reducers can help achieve optimal printing results and improve the efficiency of the screen printing process.