Additive allows laser marking on clear films
coatings that could be used to provide a narking technology for
transparent packaging material, such as blisters used for
pharmaceuticals.
The launch represents an extension of Sherwood's DataLase product range, which was first introduced earlier this year. This is colour change process for the high speed printing of images using low power laser light that can be used for applications such as coding and dating of products, printing graphics, and security marking.
The new product - DataLase Clear - enables images to be transferred into transparent media via a laser without interfering with the translucency of the substrate. It uses a combination of chemistry, substrate conversion and lasers to allow text and images to be marked directly onto transparent materials.
The technology "offers higher fidelity imaging compared to traditional coding and marking processes such as thermal transfer and inkjet. More importantly, because this process does not require the use of inkjet fluid or transfer ribbons, there is little maintenance involved," said Sherwood.
The company says that one important aspect of the new technology is the ability to form images directly between the layers of a clear laminate film, or self-adhesive label, while retaining the integrity of the uppermost layer. This provides a permanent image that is resistant to abrasion are guaranteed, as well as preserving the integrity of the film, which could be an issue in environment-sensitive products such as pharmaceuticals.
Furthermore, the embedding of the laser coating within a laminate construction could be used to provide both overt and covert security features as brand protection devices.
The process is carried out either by doping the additive directly into an existing coating or by a separate coating operation. This creates a Laser imagable transparent layer within the product. When the coated material comes into contact with the output from a low power CO2 laser, it changes from clear to black, producing a high contrast indelible image. The additive is non-hazardous, and the low power laser output prevents burning of the substrate. Furthermore, DataLase Clear is compatible with a wide range of binder systems and ketonic, aromatic, and ester solvents.
