Tantec - Plasma and Corona Surface Treatment for Better Adhesion

The Tantec Group is a privately held company founded in 1974, and is a leading manufacturer of standard and customized corona and plasma systems for surface treatment of plastics and metals for improved adhesion properties.

Tantec surface treaters are sold worldwide to end-users and OEMs through more than 30 partners and through our own branch offices.

WHAT IS PLASMA AND CORONA SURFACE TREATMENT?

It is often necessary to bond plastic materials to metals or other plastics, or simply to print on a plastic surface. In order for this to succeed, the liquid coating, adhesive or ink should be able to wet the surface of the material.

Wettability depends on one specific property of the surface: surface energy, which is often referred to as surface tension. Surface energy and surface tension are measured in mN/m.

The higher the surface energy of the solid substrate in relation to the surface tension of the liquid, the better its wettability, and the smaller the contact angle. In order for a proper bond to exist between a liquid and a substrate surface, the substrate's surface energy should exceed the liquid's tension by about 2 mN/m-10mN/m.

NEEDLETEC – SURFACE TREATMENT OF NEEDLEHUBS PRIOR TO GLUEING

Tantec's new corona treatment system for plastic needle hubs, NeedleTEC, is the answer to production problems related to bonding and leakage. Treating the needle hub's surface increases surface wettability and adhesion properties through electrical discharge.

Due to the corona treatment's ability to achieve extremely high tensile strength, it has become one of the most common methods used to treat hub surfaces. For example, untreated hubs present tensile strengths are between 18N-25N, whereas Corona-treated hubs achieve tensile strengths up to 75N.

VACUTEC - SURFACE TREATMENT OF CATHETERS WITH VACUUM PLASMA

By increasing the surface energy of catheters, vacuum plasma treatment improves the bonding properties of coatings - thereby adding extra safety and reliability to the product.

The process chemically roughens the surface, and allows it to 'grab onto' the coating being applied. The resulting chemical bond that occurs with the surface is thus stronger than a simple mechanical bond.

Before treatment, silicone's surface energy is only 38mn. Vacuum plasma treatment nearly doubles the surface energy to 72mn - which is necessary for coatings to wet the surface and adhere properly.

ROTOTEC – SURFACE TREATMENT OF OPTHALMIC LENSES PRIOR TO COATING

Ophthalmic plastic lenses are sophisticated products, and their performance relies very much on the surface treatments they are undergoing in the manufacturing process prior to applying i.e., tinted, photochromism or hard coatings.

Tantec's RotoTEC units are in-line o-ring belt conveyors with an integrated rotary electrode system to ensure an extreme uniform corona-discharge distribution on the optical surfaces.

Surface tensions as high as water wet ability (72mN/m) are achieved, which makes a RotoTEC unit indispensable prior to the washing of the lenses. As the water spreads evenly on the surface, an ultra-clean surface is presented to the following coating processes.

After washing and drying, the Corona treatment effect is more or less gone, therefore, the lenses are passing through a second RotoTEC unit on the line to re-establish high surface tension before the first coating process. A third RotoTEC is required downstream, if a further layer of coating is prescribed i.e., photochromic or hard coatings.

SYRINTEC – SURFACE TREATMENT OF SYRINGE BARRELS

SyrinTEC is specially designed for optimising for optimising the adhesion properties of printing inks onto syringe barrels which are normally made from low surface energy polymer materials.

SyrinTEC operates using highly durable ceramic electrode elements resulting in complete and uniform treatment of the syringe barrels. SyrinTEC includes a high-frequency generator, high-voltage transformers, treating station with 9 to 11 electrode elements and an ozone filter.