Controlled adhesive activation
15 August 2017
A carbon infra-red (IR) system from Heraeus Nobleight is helping Lohmann Technologies UK to achieve accurate control over adhesive activation temperature – an essential stage in the production of specialist tape. It is incorporated in an Elite Cameron laminating machine from TS Converting.
Lohmann Technologies UK offers tailor-made technical adhesive solutions and adhesive tapes for manufacturers, designers and OEM customers in the automotive, consumer goods, construction and medical sectors. Custom-designed tapes are often of a laminated construction, where an adhesive is applied to a release paper, which is then laminated onto a suitable fabric or substrate. In use, the release paper is removed and the adhesive activates through pressure or heat so that the tape can be bonded to a surface.
However, sometimes it is necessary to pre-activate the heat curing adhesive during sub- assembly manufacture so that it sticks to the release paper and the substrate and is then ready for final heat curing. Pre or final activation takes place when heat is accurately controlled in the laminating system. Lohmann make extensive use of Elite Cameron Laminating machines from TS Converting and these can be fitted with a temperature-controlled water-filled hot roller system. Lohmann decided to investigate the use of infra red for this vital heating stage and consequently, trials were carried out in Milton Keynes, using a carbon medium wave infra-red cassette from Heraeus.
These proved so successful that a full scale 22kW system was fitted to Lohmann's Elite Cameron machine and this now raises the heat the laminated tape to the adhesive pre-activation temperature of 60-70°C at a web line speed of around 11m/min. The actual power output of the IR is linked to the web speed control.
"We are very pleased with the new infra-red system," comments Paul Summers, the project engineer at Lohmann, "We have better control over the heating process, and the infra-red is easier to use and much cleaner than the heated roller system. It also offers better heat transfer over a larger area and its fast speed of response means that we can minimise any damage to the tape caused by over-heating in the event of any unanticipated stoppage.
Heraeus specialises in the production and application of high quality energy sources covering the electro-magnetic spectrum from ultraviolet to infra-red. It has over 40 years experience in infra-red technology and offers the expertise, products and systems to provide efficient and effective solutions to drying, heating and curing problems throughout industry.