Screen printing is a commonly used process in the premium segment, which especially emphasizes opacity, sharpness and brilliance of the print images. This process uses a rubber squeegee to transfer the printing ink through a screen mesh onto the article surface. Those areas of the screen mesh, which should not transfer ink, are being blogged with a stencil.
Our machines allow to decorate a large range of materials, such as glass, ceramics and plastics of various sizes and shapes. The production rate of our machines is up to max. 250 ppm.
We can use, depending on the material of the article, either UV inks or ceramic inks with the screen printing process.
Printing with ceramic inks requires the use of screen mesh, which are being heated with special screen heaters. Afterwards, the printed ink is being fired at high temperature into the article surface.
On the other hand, UV inks are being cured immediately after the printing process, using an ultra violet light source. To do this, special UV aggregates are being used, which cure and harden the ink immediately after the printing process and also ensure the over printability. High temperature firing of UV inks is not necessary.
The Koenig & Bauer Kammann UV-Technology has been developed in-house and is characterized by it’s short set up times and it’s low maintenance cost. The system is closed and features a cooling system with filtered air and a tool less insert system. The intensive focus line achieves best possible curing results. Alternatively, like we do in the digital printing process, we can integrate LED UV curing aggregates into any machine type.
To achieve the best possible ink adhesion, we can use various pre-treatment processes, which help to decontaminate the article surface and to prepare it for optimized adhesion.
The digital printing process allows to apply individual, personalized and fotorealistic print images on a large variety of materials and shapes (e.g. round, oval, flat or angular). This process allows to decorate articles with a diameter of up to 120mm and a length of 450mm. The max. print image height is 220 mm. Because digital printing is a contactless process, we can print on areas, which can not be decorated using the screen printing process.
Unlike screen printing, the digital printing process does not need a film positive (litho), because the pre-press step takes place at the computer. The image files are in a first step linearized by using a RIP (Raster Image Processor) and then converted into a graphic file, which is usable for our printing machine.
Additionally, we create an ICC-profile (Internal Color Consortium), in order to convert the color between between different color spaces.
The print image is created from 4 process colors cyan, magenta, yellow and black (CMYK) and can optionally be extended with the color white and possibly other custom colors. In addition, we are able to print an adhesion promoter and a protective varnish, in order to ensure the best possible adhesion on glass and on plastic.
A combination of different printing processes within a machine can be realized and allows to use the strength of each process.
Koenig & Bauer Kammann will be pleased to answer any questions you might have with regards to Colour management and Optimization of your digital work flow.
Hot stamping is a process, which transfers a coloured layer from a carrier foil with a transfer die or a transfer wheel onto the article to be decorated. Pressure, heat and contact time are the main variables in this process. Glass articles require a special screen printed primer on the article surface in the shape of the artwork. The foil is only transferred in those areas, which are printed with the primer.
Hot stamping on plastic articles does not require the application of a primer prior to the foil transfer. The material and special transfer tools allow a direct application onto the article surface.
The transfer tool is during the transfer process in contact with the hot stamping foil, which consists of multiple layers. A dividing layer is applied onto a carrier foil, which acts as a substrate. The dividing layer melts through the impact of the heated transfer tool and releases the transfer layers. The transfer layers include the decorative layer and the adhesion layer. The adhesion layer (a reactive glue) links the decorative layer durably and wipe-proof to the article substrate.
Hot stamping stations can be used in combination with screen- and digital printing stations and allow large variety of decoration possibilities. The max. hot stamping image height is 200 mm, independent of the material.