PUR’s role in surfaces

Kleiberit claims it has set the standard in the field of polyurethane adhesives for more than 20 years and that this strength is aptly portrayed in its motto - 'Competence PUR!'

Kleiberit realised there was a chance to extend its competence in PUR hot melts to the lacquer industry and it says this ultimately resulted in an alternative to traditional lacquering technology, with the added advantage of a much simpler application process. Kleiberit HotCoating® technology, for both rolled materials and flat substrates, offers a wide variety of advantages, says the company: One processing step; no interim sanding; 100% solid content; smaller production area; lower capital expenditure; reliable production; and variability.

HotCoating®
Kleiberit says its HotCoating is an innovative coating based on a reactive PUR hot melt system. It is solid at room temperature and is melted with a pre-melter before being applied to the substrate. Coating weight is adjustable depending on customer requirements. The chemical cross-linking with the humidity of the PUR material results in a very resistant surface which is extremely shock and wear resistant (up to AC3), claims Kleiberit.

An additional very thin layer (inline) application of Kleiberit's UV-curing TopCoat allows for precise variations in gloss level and variations in colouring. In addition, it allows the PUR to cure over a longer period without damage because the UV TopCoat gives immediate scratch resistance, it says.

"Not only does Kleiberit HotCoating offer many advantages in comparison to traditional lacquering technology, customising features such as staining or printing (digital or direct) can also be easily integrated into the Kleiberit HotCoating inline process," says the company. "This means that wrapping materials such as veneer and decorative paper can be individually designed and finished in a single piece flow according to customer requirements."

Kleiberit says its customers are already producing veneer rolls which are individually coloured with stain before Kleiberit HotCoating is applied to achieve a surface coating which protects the veneer and makes it very flexible.

HotCoating flat components
The flooring market is no longer just limited to parquet: solid wood flooring versus laminate flooring. New products and further developments have led to differentiation and the field of solid wood products has expanded to include solid wood flooring, engineered multi-layer parquet, veneered flooring with HDF or MDF cores and printed veneer floor.

Laminate flooring has also expanded and is no longer just traditionally-made laminate floor produced as direct pressure laminate (DPL), this field has also expanded to include high/continuous pressure laminate (HPL/CPL), printed direct laminate (PDL), digital printed laminate and paper flooring.

Regardless of whether its veneer flooring, paper flooring, direct printed or digital printed flooring, the following holds true:

• Protection is required with a resistant Coating
• Sanding is not possible
• Additional requirements: natural feel, pores, transparent coatings.

Kleiberit's HotCoating technology is claimed to meet these requirements with a simple-touse, compact technology:

• Protection with AC3 coating
• No intermediate sanding required
• Transparent
• Universal adhesion
• Imprinting of three dimensional structure, ie pores.

In the flooring market, differentiation and customisation are also in demand, and there is a wide variety of systems attempting to meet customers' demands in different ways.

Decorative and digital or direct print surfaces need to be protected with a shockand wear-resistant coating, but the surface cannot be sanded prior to the coating process.

Kleiberit says its HotCoating has excellent universal adhesion to various materials such as paper, print colours and lacquer systems, making it the ideal coating for decorative and printed surfaces - sanding is not required.

Kleiberit HotCoating is transparent, so it does not affect the optical qualities of the surface. It is also very shock- and wearresistant, so the finished product is very durable, says the company.

Flooring applications with decorative surfaces or digital/direct printing are suited for long-term use when coated with its HotCoating, says Kleiberit. "As a result of the extraordinary flexibility, there is no microcracking, which can destroy the sealing characteristics. Even with a low coat weight, Kleiberit HotCoating offers a very high wear resistance," it claims.

Glossy surfaces
The worldwide trend towards high-gloss surfaces in interiors, furniture and flooring places new requirements on processes and products. Kleiberit says it has developed diverse innovations specifically for high-gloss which are tailored to those requirements.

The perfect high-gloss surface combines cost-effectiveness and technical feasibility.

Main factors are: maximum gloss level; smooth surface; depth effect; resistance; cost; process technology; and design variety.

The generally recognised high-end area is the mirror and real glass surface.

There are several ways to create a high gloss surface and Kleiberit says it offers a solution for all.

It says the following process technologies are in trend:

1. Laminating high gloss foils onto wood based panels with PUR hotmelt adhesive

2. Bonding transparent material with Kleiberit PUR hotmelt adhesives

3. Kleiberit HotCoating on melamine faced wood based panels.

Inline digital print
In all industries, there is a trend to smaller batch sizes, says Kleiberit: "Excluding highvolume markets, the tendency is very clear that end-users, architects and designers want to have personally designed furniture, windows, doors or flooring.

"Companies producing these kinds of components have to increasingly have the possibility to produce an individuallydesigned component in one batch size. To be able to do this in a cost effective way, these companies cannot work with minimum quantities in purchasing decorative material.

In addition, they have to be able to precisely follow the customer's requirements in design very quickly. Kleiberit says its HotCoating and digital printing technologies are ideally suited to meet these demands.

"Digital printing technology's philosophy mirrors that of Kleiberit HotCoating and allows users to create even small batches of very high quality decorative material."

Kleiberit also says its HotCoating, like digital printing, is a technology which is not too complex to allow users to create even small batches with a very high-quality, protective and durable finish.

"This allows everyone the opportunity to create individually designed wrapping material and to protect it inline with a very durable and flexible coating - all with a very simple-to-use technology which is absolutely flexible and low in capital investment," says the company.

In its Technical Centre in Weingarten, Kleiberit's processing technologies are available on a production scale, where it says product developments - and customer demonstrations - can be conducted in full scale.