PRINTING

Do you need a quotation or advice about our processes and services?
Our technical project manager Caroline Deutschmann, is happy to answer any of your questions.
Contact her directly at +49 (0)2352 9781 0.

PRINTING & LABELLING METALS, PLASTICS AND WOOD

Seltertech offers printing and labelling services on metals, woods and plastics. Each procedure is done using thermal transfer printing, laser printing, CIJ and electrolytic labelling on designated surfaces. We apply various methods within the following technical parameters.

TECHNICAL PARAMETER THERMAL TRANSFER PRINTING

• Width of 16 – 130 mm
• Printing area of 106 mm
• 240 g/m² to
• Resolution of 300dpi

TECHNICAL PARAMETER LASER LABELLING

• Hang-tags width of 150 mm
• Hang-tags length of 210 mm

TECHNICAL PARAMETER CIJ – CONTINUOUS-INKJET-PRINTING

• Printing speed of up to 12 m/s by 7 x 5-Matrix
• Character height: from 0.8 to 20 mm
• Fonts: 5 x 5 to 32 x 32
• 1-5 lines
• All fonts and graphics are freely positionable and combinable
• All major barcodes / Data Matrix code (ECC 200 and EAN / ECC)
• Time, date, expiry date, CW, Julian calendar, timer
• 10 programmable counter for numbering, production counter and metering
• Multilevel contrast and bold feature, print repetition, delayed printing, backward printing, text rotation 90° / 180°, reflection, inverting, reversing and alternating print out (also object-oriented).

TECHNICAL PARAMETER CIJ ELECTROLYTIC LABELLING

• With an inscription window of X mm x X mm

THERMAL TRANSFER PRINTING

PROCEDURE

Thermal transfer printing on metal, is done by generating heat to the printed design (Greek thermós = warm) without having any major mechanical influence on the printing material. The resulting print is very durable and can be used on a variety of printing substrates.

The print head for a thermal transfer printer has multiple heating elements, called dots. To print on substrates, such as paper labels, a special colour film (ink ribbon) is synchronously moved along the print head. The dots are heated according to the desired printed image. Heating then initiates the transfer of colour to the printing material.

With thermal transfer printing, the interaction among the thermal transfer printers, the ink ribbon and the paper to be printed is crucial in order to obtain a high quality label.

We use printed cardboards for inscribing labels and hang-tags in thermal transfer printing. Additionally, we use a laser labelling station for inscribing hang-tags with EAN barcode.

USE

Through its versatility, thermal transfer printing is applicable in a wide range of areas. Printing singular data, serial numbers and individual labels as well as processing data in large quantities is possible. Thermal transfer printing is especially suited for producing barcode labels, as its superb contrasting allows a high scan rate. A customized thermal transfer printing label has a comparably long life expectancy. If the right combination of substrate material and thermal transfer ribbon is selected, they are also resistant to mechanical and chemical influences.

AREAS OF APPLICATION

• Product labelling
• Shipping and transport labelling
• Food labelling
• Labelling in the automotive industry
• Quality control labelling
• Device coding

MATERIALS FOR THERMAL TRANSFER PRINTING 

Due to the versatility of thermal transfer printing, the following is a list of the most common materials available since there is an abundant supply:

• Polyethylene films
• Polypropylene film
• Polyester films
• PVC films
• Paper (standard paper, chromo paper, brilliant paper – depending on the use of the label, the quality and durability of printing)
• Textile fabric
• Direct printing on products and product packaging

ADVANTAGES OF THERMAL TRANSFER PRINTING

The main advantages of thermal transfer printing is the low cost of printing and the high durability of the printed image. Moreover, it is an advanced, long-lasting yet low-maintenance technology. The contour definitions and contrast are very good, which is especially advantageous for barcoding.

Within the professional arena, the set-up costs are eliminated when compared to other printing techniques such as screen printing.

Printing in many colours is possible, using a wide range of thermal transfer films – including special colours such as silver and gold.

ADVANTAGES OF THERMAL TRANSFER PRINTING

The main drawback is certainly the monochrome, rasterized print. Full coloured images or photos are impossible with the thermal transfer printing process. However, there are various work-around techniques for multicoloured pictogram.

In comparison to thermal direct printing, there is the disadvantage of two separate used materials exists in paper and ribbon. With thermal direct transfer, only the paper must be replaced (see also Comparison: Direct thermal or thermal transfer).

LASER MARKINGS

PROCEDURE

Laser markings or inscriptions are durable, abrasion-resistant and very legible. With laser engraving many materials can easily be identified. A permanent inscription is also achievable without used material.

USE

• Laser inscription on glass
  Laser markings can also be used on glass. As with all other surfaces, the labellings are durable and abrasion resistant. Laser inscriptions are often used particularly within the beverage industry on drinking glass.
• Laser inscription on ceramic
  Whether it is a flowerpot in the garden or cups in the dishwasher – ceramic products are often exposed to harsh environments. Here a permanent laser marking is often the right choice.
• Laser inscription on wood
  Wood products are often exposed to corrosive substances such as rinsing or washing. Laser inscriptions remains even during the use of these substances.
• Laser inscription on plastic
  Laser can also be used for labelling plastic. Even on PET bottles, which consist only of very thin plastic. Laser engraving can be used without any problems.
• Laser inscription on rubber
  In many industries, gaskets and other rubber products are used. They often have to be traced back to the production site. To rule out manipulation, laser markings are therefore used. The properties of the material are not affected in this case.
• and many other materials …

OVERALL BENEFITS

• Labelling is possible when product is stationary or in motion
• Labelling speeds of up to 300 m per minute or 1,800 products per minute
• Avoid using used items such as ink or labels

TYPES of LASERS

CO2-Laser

CO2 laser markers are used for inscribing various types of materials: plastic, rubber, paper, cardboard and films as well as coated metals.

Whether it is expiry dates, barcodes, serial or product numbers – CO2 lasers provides clean and reliable inscriptions, no matter the industry.

CO2 lasers are suitable for engraving almost all materials (removing the top layer).

Fibre Laser

Fibre lasers are used for engraving or making annealed inscriptions on stainless steel and metal or to change the colour on plastics.

Advantages of fibre lasers

• universally applicable
• easily integrated into existing lines
• improved beam quality compared to CO2 laser
• power spectra of 5/10/20/30 / 50 W
• marking fields sizes from 70 x 70 mm to 300 x 300 mm
• IP52 / 54
• Life expectancy 100,000 hours

YAG lasers (diode-pumped lasers)

Due to the special features of the YAG laser, one can create better colour changes on some plastics than with fibre laser.

Advantages of YAG lasers

• universally applicable; ideal for workshops / manual workstations
• due to other pulse length / pulse peak power can achieve a better contrast on some plastics than with the fibre laser.
• power spectrum of 4 W
• marking field size of 70 x 70 mm
• IP52
• Life expectancy 20,000 hours

INDUSTRIAL CIJ PRINTER (CONTINUOUS INKJET PRINTERS)

PROCEDURE
These devices are used for non-contact labelling of moving objects on production conveyor belts. There are also systems with mechanized or manual feed to the print head for labelling stationary objects. The devices are characterized by high printing speed on any surface. Such printers with continuous inkjet belong to a category of printers for so-called small fonts. (SCP – Small Character Printer)

For labelling:

• Automotive parts
• Cable + jack
• Steel + metal
• Wood
• Rubber + plastics
• Components
• Food + Drink
• Packagings
• and other products

ADVANTAGES

• The biggest advantage of the inkjet printer is the relatively simple structure of the device and its associated low manufacturing cost. In recent years, the results achieved a quality – at least on special papers – that other methods only rarely accomplish or at a high cost. The page throughput in text printing for inkjet printers comes close to laser printers. On coated paper, the difference in typeface is hardly discernible. The quality output of digital data through printing is very reasonable in relation to the material costs; however, the devices are profitable only for larger companies because of its high purchase prices.
• Some inkjet printers achieve remarkable colour spaces – only full colour systems and thermal sublimation printer offer greater colour spaces. The former are unable to be purchased for personal use, while the latter is higher in its consumption costs.

DISADVANTAGES

• Inkjet printers are sensitive to the medium to be printed; many inks are neither indelible nor archive proof (water-soluble, long-term chemical changes). Fading, particularly under the influence of short-wave light components (daylight), is considerably stronger than with other methods, so they are not used for laser printing; however, inkjets can be used with non-fading colour pigments.
• The highest quality is achieved only on relatively expensive special papers, which cause in some cases, page prices to be more than one euro per A4 page. However, ordinary paper is sufficient for most applications. The cost to print black and white remains stable while coloured prints are rather lower than coloured laser prints. However, considerably lower cost can be achieved with pure black/white laser printers.
• Furthermore, the inkjet systems tend to dry out, whenever not much printing is being done. This results in expensive ink replacement and / or print heads.
• Inkjet printers are not suitable for bulk printing, because they are usually slower. Either laser-, offset- or gravure printing process is used depending on the print run.

ELECTRONIC LABELLING

PROCEDURE

Electrolytic marking and labelling is used for directly labelling electrically conductive material surfaces. A control unit, a template and electrolytes are required for this marking process.

In the electrochemical process, the basic structure of the material surface is rapidly forced into oxidation, which enables penetration into the material surface. The term oxidation comes from chemistry and means that a material forms a bond with oxygen, and then triggers a chemical reaction. The electrolytes are composed of various salts.

ADVANTAGES

Electrolytic inscription was developed for signing electrically conductive product surfaces. Within a short time, you will get a high-contrast, permanent marking, which is corrosion-free and resistant to seawater, abrasion, acid and sterilization resistant.

The electrolytic inscription as a method of marking is very affordable and economical. Graphics, numbers, letters, codes, symbols, etc. can easily be labelled electrolytically.