Herma adds 62F clear-on-clear label adhesive

Clear-on-clear labels make a sophisticated impression but can be problematic if required to withstand wet conditions, said Herma, with the framing effect especially undesirable. This occurs when moisture causes an unsightly white haze to creep across the applied label from its edges.

62F has been shown to eliminate this problem. Even when tested by immersing in water for 96 hours, it failed to trigger any clouding. The adhesive is further characterised by high initial tack and very good resistance to oils and aqueous media.

Alongside its other benefits, the 62F grade is not subject to secondary cross-linking (unwanted hardening) in connection with multi-color printing and prolonged UV curing. The adhesive therefore retains good flow behaviour. Further, to ensure that the labels preserve their qualities for their entire life, the new grade offers especially good resistance to light, heat, water and ageing.

The permanent UVA adhesive has been designed specifically for clear-on-clear applications in which moisture is a factor, as in the drinks industry, but is also suitable for challenging and critical applications in the cosmetic, food and pharmaceutical industries. In view of its unconditional approval by the German test institute ISEGA, it is also suitable for direct contact with dry, moist and fatty foodstuffs.

The new adhesive 62F is most effective in combination with the label film Herma PP 50 Transparent (grade 885). Thanks to special surface treatment, this film delivers good print quality with all conventional printing techniques.

The clear-on-clear adhesive 62F is the latest addition to Herma’s range of speciality products. ‘Grade 62F further underscores our existing strong reputation as a problem-solver,’ commented Herma managing director Dr Thomas Baumgärtner. ‘Our standing has encouraged us to focus investment activity on ultra-modern production technology in the last few years.’

By way of example, Herma recently retrofitted a special, precision-dosing rotating bar nozzle to an existing coating plant for UVA adhesives, as reported here. The nozzle applies the adhesive within extremely small weight tolerances to achieve an ultra-smooth finish, even with high grammages. ‘For special clear-on-clear labelstock in particular, this is an essential precondition,’ stated Baumgärtner.