Gravure Coating : Hot Melt Selective Coater

The gravure coating process relies on an engraved roller running in a coating bath, which fills the engraved dots or lines of the roller with the coating material. The excess coating on the roller is wiped off by the Doctor Blade and the coating is then deposited onto the substrate as it passes between the Engraved roller and a Pressure Roller.

This is developed in 2006 & Exhibited in IIASE'07 at Nehru Center, Bombay.

This machine uses the old technique of Gravure coating; whose versatility has been increased by recent technology developments. A gravure roll has been adopted to accurately carry out the coating of Hot Melt (Pressure \ heat Sensitive) Adhesive using an extremely small amount of material. This results in stable bead, which when combined with lamination application gives very good quality and a constant coating weight.

The absence of solvents, volatile parts and water, offers an environmentally friendly operating process, and since no additional heating energy is required to evaporate water or solvent and the curing takes place by ambient air temperature or by the humidity of the ambient air, no drying or curing ovens are necessary.

The gravure of the roller exactly determines the desired uniform add-on and the pattern on the substrate. This is required for minimum coating weights, good bonding strength and soft touch.

A tremendous choice of gravures allows an optimal selection of coating patterns and weights. The coating patterns range from regular geometric patterns to random dots and nets and other optical effects.

Advantages of this system are :

  • Easy to operate
  • Minimal equipment set-up
  • Simple coating supply system

Disadvantages of this system are :

  • No gravure wear compensation
  • Special gravure pattern required
  • Increased open surface allows for heat loss

Machine in operation