Direct thermal is a ribbon-free printing system: the printhead applies heat directly to a sensitive face material and the image appears with no transfer ribbon. It is fast, simple and economical. But "direct thermal" does not describe a single material — it describes a family, and within it there are important differences in durability and resistance. This guide runs through the three common grades so the choice starts from the real environment of use. If you are looking for an overview of the system, the direct thermal labels material page gathers the rest of the context.
The most common mistake: ordering "direct thermal" without specifying the grade. The supplier sends standard paper, and the label ends up in an environment that paper was never meant for.
Standard thermal: paper with no protective coating
Standard thermal is thermal paper with no varnish coating on the sensitive face. It is the most economical grade and the starting point of the family. It prints well and covers internal labelling where the label has a short life and does not face aggressive agents.
Under normal indoor warehouse conditions, its service life is around 12 months; heat, intense light and humidity shorten it. The image has no protective coating, so friction, grease and plasticisers degrade it. It is paper: it does not resist permanent water or continuous abrasion.
Typical uses
- Scale and weighing labels at the point of sale.
- Picking, order preparation and internal logistics.
- Delivery notes and short-life dispatch documentation.
- Shipments and traceability where the label does its job for days or weeks.
⚠ Worth noting
Traditional thermal paper can contain bisphenol A (BPA) or bisphenol S (BPS) as a developer. For food or pharma it pays to specify a BP Free paper without bisphenols — a point covered in the next section.
Top: thermal paper with a protective varnish
Top is thermal paper with a varnish coating added on the sensitive face. That varnish coating improves resistance to friction, grease, humidity and light. Print legibility can hold up for about 2 years in normal indoor conditions. It is still paper: not suitable for prolonged outdoor exposure or high heat.
It is the right grade when the label will be handled, will be near greasy product or needs to withstand more than a quick shipment. As a real-world reference, Lit-Off's Ref. FH21 is a BP Free top thermal paper, free of BPA and BPS, with ISEGA approval for indirect food contact and FSC Mix Credit certification. It carries a rubber hot-melt adhesive with good initial tack on a wide range of surfaces.
Typical uses
- Food labelling at room temperature, where resistance to grease and freedom from bisphenols are needed.
- Pharma and parapharmacy with traceability and handling requirements.
- Retail and end products that are handled repeatedly.
- Logistics with intensive handling or medium service life.
PP direct thermal: a plastic face material instead of paper
PP direct thermal replaces paper with a polypropylene face material — a plastic film — while keeping the sensitive face for ribbon-free direct thermal printing. Plastic face material: resists permanent moisture, condensation, tearing and the cold chain. The print is still direct thermal — sensitive to heat and light even though the face material holds up. Its mechanical durability is greater than paper's; the exact life depends on the application.
As a real-world reference, Lit-Off's Ref. A10 is a 75 µm white polypropylene film for ribbon-free direct thermal printing. It carries the A10 adhesive, a water-based permanent acrylic, approved for direct food contact. It applies from −10 °C, has a service range of −15 / +60 °C and is suitable for the cold chain.
Typical uses
- Frozen and chilled products, including the cold chain.
- Humid environments or with permanent condensation.
- Applications where the label can get wet or be washed.
- Food labelling that requires direct food contact.
PP thermal solves the face material problem — moisture, cold, tearing — but not the image's. Like all direct thermal printing, it is still sensitive to heat and light; the plastic does not change that part.
Comparison table of the three types
| Type | Face material | Indicative durability | Face material resistance | Cost | Typical use |
|---|---|---|---|---|---|
| Standard thermal | Paper | ~12 months indoors | Low | Low | Scales, picking, internal logistics |
| Top | Paper with varnish | About 2 years indoors | Medium | Medium | Food, pharma, retail |
| PP thermal | Polypropylene | Long, depending on the application | High | High | Frozen, chilled, humid environments |
Indicative values for normal conditions of use. Image durability always depends on the heat, light and humidity of the specific environment; the "face material resistance" column refers to mechanical and moisture resistance, not the print's resistance to light.
When direct thermal is not the right choice
Direct thermal stands out for its simplicity and cost, but it has a clear limit: the image is thermal and therefore sensitive to heat and light. There are applications where that limit shows up too soon.
For a service life of more than two years, prolonged outdoor exposure, high heat or direct UV radiation, it is worth looking at coated paper printed with a ribbon or, depending on the case, polyester printed by thermal transfer. Coated paper with a ribbon keeps the image stable for far longer than any direct thermal; the coated paper material page covers when it is the right choice. For truly demanding environments — chemicals, intense abrasion, high temperature — polyester is the reference face material.
"Direct thermal is excellent as long as the label lives indoors and for a short time. As soon as sun, heat or years come into play, the right system is a different one."
Not sure which grade of direct thermal your application needs? Tell us the environment and the service life required.
Ask with no obligationFrequently asked questions
How long does a direct thermal label last?
It depends on the grade. Under normal indoor warehouse conditions, standard thermal paper lasts around 12 months; top paper can keep its legibility for about 2 years. Heat, intense light and humidity shorten that life in all cases. PP thermal has greater mechanical durability than paper, but the image is still direct thermal and sensitive to heat and light.
What is the difference between standard and top thermal?
Standard thermal paper has no protective coating, so friction, grease and plasticisers degrade the image. Top adds a varnish that improves resistance to friction, grease, humidity and light, and extends legibility. Both are still paper: neither is suitable for prolonged outdoor exposure or high heat.
Is direct thermal suitable for frozen products?
For frozen and chilled products, PP direct thermal is the right choice, with a plastic face material that resists permanent moisture, condensation and cold. Lit-Off's Ref. A10 is a PP thermal film that applies from −10 °C, has a service range of −15 / +60 °C and is suitable for the cold chain. Thermal paper is not the right choice in those environments.
Can direct thermal be used outdoors?
Direct thermal is not the right choice for prolonged outdoor exposure. The image is sensitive to light and heat, and degrades with sun exposure. For outdoor identification with a long service life, coated paper with a ribbon is a better choice, or better still, polyester labels printed by thermal transfer.
Does thermal paper contain BPA?
Traditional thermal paper can contain bisphenol A (BPA) or bisphenol S (BPS) as a developer. BP Free thermal papers without bisphenols exist, recommended for food and pharma. Lit-Off's Ref. FH21 is a BP Free top thermal paper, free of BPA and BPS, with ISEGA approval for indirect food contact.
Does direct thermal need a ribbon?
No. Direct thermal is printed by applying heat directly to a sensitive face material: it uses no ribbon or transfer tape. This simplifies the printer and reduces consumables, but it is also why the image is sensitive to heat and light over time.
Which type of direct thermal should I choose for food labelling?
For food labelling at room temperature, a BP Free top thermal paper such as Ref. FH21 covers resistance to friction and grease, freedom from bisphenols and approval for indirect food contact. For frozen, chilled or humid environments, PP thermal such as Ref. A10 — with direct food contact and suitability for the cold chain — is the right choice.
Summary
Direct thermal spans three grades with different performance. Standard is the paper without a protective coating, economical and suitable for short-life internal labelling. Top adds a varnish that improves resistance to friction, grease and humidity, and is the usual grade for food, pharma and retail.
PP thermal replaces paper with a polypropylene face material: it resists moisture, cold and tearing, and is the choice for frozen products and humid environments. In all three cases, the image is still direct thermal and sensitive to heat and light.
To learn more about the complete system, see the direct thermal labels material page. If your application demands more than direct thermal can give, tell us the environment of use and we will point you to the right material.