In Direct-to-Film (DTF) printing, DTF adhesive powder forms the bonding layer that attaches the printed image to fabric during heat pressing.
One of the most important characteristics of this powder is particle size.

Particle size influences how evenly the powder covers the printed image and how the adhesive layer forms during curing and heat transfer.
For this reason, DTF adhesive powders are commonly categorized according to their particle size distribution, typically measured in microns.

Understanding powder particle size helps clarify how different powders behave within the DTF transfer process.

What Particle Size Means in DTF Powder

DTF adhesive powder consists of thousands of small thermoplastic polymer particles.

The particle size refers to the diameter of these particles, usually expressed in micrometers (µm).

For example:

  • 80 µm particles are very fine
  • 120 µm particles are medium size
  • 200 µm particles are relatively coarse

Manufacturers typically specify a particle size range, rather than a single number, because powders naturally contain particles of slightly different sizes.

Example ranges often seen in the industry include:

  • 80–170 µm
  • 100–200 µm
  • 120–250 µm

These ranges describe the distribution of particle sizes within the powder.

Common Particle Size Categories

Although exact specifications vary by manufacturer, Adhesive powders are typically categorized by polymer composition and particle size.

Fine Powder

Fine powders typically fall within ranges such as:

  • 80–120 µm
  • 80–170 µm

Because the particles are small, they can spread easily across detailed printed areas.

Fine powders are often associated with:

  • smoother adhesive layers
  • better coverage of small details
  • thinner adhesive buildup

Medium Powder

Medium powders often fall within ranges such as:

  • 100–200 µm
  • 120–200 µm

This size category is commonly used in many DTF printing systems because it balances coverage and handling.

Medium particle sizes allow powder to distribute across printed areas while still forming a consistent adhesive layer after curing.

Coarse Powder

Coarser powders may include ranges such as:

  • 120–250 µm
  • 150–300 µm

Larger particles tend to form a thicker adhesive layer once melted.

Because of their size, coarse powders may produce a more textured adhesive surface compared with finer powders.

How Particle Size Affects Powder Coverage

When powder is applied to freshly printed film, the particles attach to the wet ink layer.

Particle size influences how this coverage occurs:

  • Smaller particles can settle into fine printed details
  • Larger particles tend to remain on broader ink areas

During curing, these particles melt and merge together to form a continuous adhesive layer.

The distribution of particle sizes within the powder therefore influences how evenly the adhesive layer forms across the printed design.

Particle Size and Powder Flow Behavior

Another reason particle size matters is the way powder moves and spreads during application.

Powder particles must flow across the printed film and attach to the ink layer before excess powder is removed.

Particle size can influence:

  • how easily powder spreads across the film
  • how evenly particles distribute across printed areas
  • how excess powder separates from the film

Because of this, manufacturers design powder particle size distributions to suit common DTF printing workflows.

Particle Size as One Parameter in Powder Classification

Particle size is only one parameter used to describe DTF adhesive powders.

Other characteristics also help classify powders, including:

  • polymer composition
  • melting temperature range
  • powder color
  • curing conditions

These parameters work together to determine how the adhesive powder behaves during the DTF transfer process.