Pad printing, screen printing or hot stamping? Choosing a process for a production part
Part geometry, artwork size and the required effect often narrow the choice before quantity does. This practical comparison shows what to verify before serial production.
Define the result before choosing the process
A production part and the artwork are on the table. You need to choose between pad printing, screen printing and hot stamping. The decision is often reduced to quantity, but it actually starts elsewhere: where exactly is the design located, how much area does it cover, and how must the result look and perform?
Small symbols near the edge of a curved housing, a large colour area on a panel and a glossy metallic band on a cap are three different production tasks. Each may point to a different process before cycle time or price is discussed. The comparison below is an initial technical screen; the final decision must be made using the actual part and an agreed test requirement.
Geometry is the first filter
A print area is more than width × height. Radii, recesses, ribs, edges, changes in level and the space available for a pad, screen or stamping die all matter.
- Pad printing uses a flexible silicone pad that rolls across the surface while transferring the image. This helps with smaller curved and detailed areas. A deep recess, sharp edge or obstruction in the pad path can still distort or prevent the rolling action.
- Screen printing is a natural candidate for larger continuous designs on flat or slightly curved surfaces. In a rotary arrangement it can also decorate suitable cylindrical or slightly tapered parts, provided they can be guided and rotated accurately.
- Hot stamping requires controlled contact between the die, foil and part. It works well on a supported flat surface, a limited cylindrical section or raised detail; a more complex shape increases the demands on the die, locating and dimensional consistency.
A flexible pad therefore does not mean ‘any 3D shape can be printed’, and screen printing is not automatically limited to flat panels. Access, movement and the fixture determine what is feasible in both processes.
Quick decision table
Production situation | Assess first | Why | What may change the decision |
|---|---|---|---|
Small, fine design on a radius, housing or detailed surface | Pad printing | A flexible pad adapts to a limited shape | Deep recess, sharp edge, large area or inaccessible position |
Larger solid area on a flat panel | Screen printing | A screen efficiently transfers a continuous ink layer to a suitable surface | Pronounced curvature, surface interruption or several height levels |
Design on a regular cylinder or slight taper | Rotary screen printing; pad printing may also suit the size | The part can be rotated in a controlled manner | Rim, projection, ovality, inaccurate guidance or design close to an edge |
Metallic, glossy or holographic appearance | Hot stamping | The effect comes from transferred foil, not metallic printing ink | Heat-sensitive material, flexible part, large solid area or poor support |
Several spot colours and precise design position | Pad or screen printing, depending on geometry | Both processes support multicolour configurations | Number of colours, intermediate drying, handling, registration tolerance and the actual machine |
Functional marking exposed to chemicals or abrasion | Select the process only after testing | Durability is not determined by the process name alone | Material, ink or foil, pretreatment, curing and actual service exposure |
This table is neither a price list nor an automatic configurator. Its purpose is to reveal missing information before tooling or a fixture is produced.
Artwork, colours and effect: define the visible result
The artwork brief should include the actual dimensions, vector data, number of spot colours and positional tolerance. A ‘colour logo’ may mean one solid colour, several separate shades or closely registered fine elements. Each version places different demands on the machine, intermediate operations and registration.
Pad printing works well for smaller symbols, logos and scales on shaped parts. For routine work, Tiskárna Jelínek has machines with a print width of up to 9 cm and a Morlock machine that, depending on the artwork and geometry, supports up to four colours within a circular area of approximately 5.5 cm. This is not a universal promise for every shape: pad access and image distortion may reduce the usable print zone.
Screen printing offers an advantage for larger areas of solid coverage, but each colour requires its own stencil and registration control. With a cylindrical product, the start and end of the design, part guidance and any interruption of the surface must also be considered.
Hot stamping produces a different type of result. The metallic shine comes from transferred foil and should not be confused with ordinary ‘gold ink’. Depending on the foil and part, gold, silver, pigment, matt, holographic or blind effects may be possible. Compatibility between the foil, substrate, die and process window is decisive.
Hot stamping also depends on heat, pressure and support
Hot stamping transfers foil through a combination of temperature, pressure and dwell time. A plastic part must therefore tolerate the process without unwanted deformation, indentation or surface change. The fixture must locate the product accurately and support it directly beneath the stamping area.
A large solid area may be more demanding than a narrow band or raised lettering: it increases the force required, the need for uniform contact and the risk of trapped air. A contoured die is also more sensitive to dimensional variation between parts. Tiskárna Jelínek operates five machines for flat, slightly curved and rotary hot stamping, but the suitability of a specific part always depends on testing the sample and selected foil.
Run size does not decide on its own
Quantity affects the economics, but only after the process can handle the geometry and required result. Preparation involves a printing plate and pad, screen and squeegee, or die and foil; all three also require a fixture, setup, inspection and sometimes intermediate drying.
For repeat production, the following may matter more than the total number of parts:
- how many part and artwork variants will alternate;
- whether the part has reliable locating surfaces;
- dimensional variation between batches;
- how quickly the part can be loaded, removed and inspected;
- whether a multicolour design requires the part to move or can remain in one fixture;
- whether the material, surface or product supplier changes.
This is why a universal rule such as ‘screen printing is always best above a certain quantity’ is not useful. The process must first be technically feasible and stable.
Durability must be expressed as a test
‘Permanent print’ is not a measurable requirement. A marking operated by a finger, a part cleaned with alcohol and a component exposed to oil, sweat, temperature cycles or outdoor conditions all require different assessment.
Before sampling, it is therefore useful to define:
- the substance, concentration, temperature and contact time for a chemical test;
- the rubbing material, load and number of cycles for an abrasion test;
- the acceptable change in colour, gloss, legibility or integrity of the design;
- the curing time before testing;
- whether the first sample, every batch or a regular control part will be tested.
Ink and foil data sheets always apply to a specific system and set of conditions. Without testing, they cannot prove that one process is generally more durable than another. Material and service exposure are discussed in more detail in Printing on plastic parts: how to choose the process.
What to send so the process can actually be selected
A well-prepared set of information is enough for the first assessment:
- a photograph of the complete product and a detail of the print area;
- a drawing or 3D data showing the position and size of the artwork;
- the exact material and surface-finish designation;
- vector artwork, spot colours and the required visual effect;
- quantity, repeat batch size and number of variants;
- a description of service exposure and an acceptable test criterion;
- several representative parts from actual production.
You do not need to specify the process in advance. For industrial printing, it is more accurate to send the part, required result and operating conditions. Pad printing, screen printing and hot stamping can then be compared for the actual production task.