What thermography is
Thermography is a print finishing process that produces raised, glossy text and images by applying a resinous powder to freshly-printed wet ink and then fusing the powder to the ink surface using heat. The result is a tactile raised surface that resembles engraving at significantly lower cost. Thermography is widely used for business cards, letterheads, wedding invitations, and formal stationery in India.
Thermography should not be confused with thermal printing (which uses heat-sensitive paper and produces flat images) or thermochromic printing (which uses colour-changing inks). Thermography is specifically the raised-powder heat-fusion process described here.
The thermography process — step by step
Step 1 — Offset printing
The design is printed in standard offset ink on paper. The thermography effect works only on freshly printed, wet ink — the wet ink is the adhesive that holds the thermography powder. Thermography is always a post-printing operation applied inline or immediately after offset printing.
Step 2 — Powder application
The printed sheet passes through a powder application unit where thermography powder is dusted evenly across the entire sheet surface. The powder adheres to the wet ink areas but not to the dry non-printed areas.
Step 3 — Powder removal (non-image areas)
The sheet passes over a vacuum collection system or vibrating brush that removes excess powder from the non-printed areas, leaving powder only on the ink-covered (still wet) areas.
Step 4 — Heat fusion
The sheet passes through an infrared or convection heat tunnel at 180–220°C. The thermography powder melts, flows into the ink, and fuses to create a raised, glossy surface. The height of the raised image depends on the particle size of the powder and the thickness of the ink layer — typically 0.2–0.8mm of raise above the paper surface.
Thermography powder types
- Clear gloss: The most common — a transparent high-gloss resin that amplifies the colour of the printed ink beneath. Used for gold, silver, and vivid process colour effects.
- Clear matte: A translucent matte resin — less common, used for subtle raised texture without the gloss shine.
- White: An opaque white powder used to create raised white text on coloured or dark backgrounds.
- Metallic (gold, silver, copper): Powder with metallic particles — gives a raised metallic appearance without requiring foil stamping. Less durable than foil but significantly cheaper.
- Colour-matched resins: Thermography powder can be tinted to specific colours — used when the printed ink below would not provide the desired final colour.
Thermography vs engraving — the honest comparison
Thermography is frequently described as a "poor man's engraving" and is sometimes used to simulate the appearance of engraved stationery. The comparison is important for clients who may be quoted either process:
- Raised appearance: Both produce raised text — thermography tends to be rounder and more dome-shaped; engraving is sharper-edged
- Back of sheet: Engraving produces a visible bruise or indent on the reverse of the sheet (the counter-impression from the die); thermography leaves no mark on the reverse
- Durability: Thermography can crack or peel if the sheet is folded through the raised area; engraving is permanent
- Cost: Thermography is 3–8× cheaper than engraving at typical India commercial quantities
- Minimum quantity: Thermography: 100 sheets. Engraving: 500+ sheets (due to die cost)
India market context
Thermography is widely available at commercial printing presses in India's major cities. It is a standard offering at business card printers in Mumbai's Lamington Road printing district, Delhi's Daryaganj area, and Sivakasi (which produces the majority of India's commercial visiting cards and stationery). The process is especially popular for visiting cards, wedding card borders and headings, and letterhead printing for professionals (doctors, lawyers, chartered accountants) who want a formal raised appearance without the cost of engraving.