Impregnation
Specialty papers, such as decor, overlay, corunded overlay and backing papers, impregnated with melamine and urea resins are used for manufacturing laminates and in further processing for decorating wood based panels.
Partly methylated melamine resins are used for impregnating specialty papers. Such impregnated papers are used for producing edge banding materials and finish foils for decorating wood based panels.
Metadynea offers market leading melamine-formaldehyde and urea-formaldehyde resins for manufacturers of impregnated papers used for production of direct pressed laminates (LPM, furniture and laminate flooring), laminates (HPL, CPL), edge banding, finished foils, pre-impregnated papers as well as for paperless direct print applications.
Due to the long term engagement in the industry, Metadynea has an understanding of the various processes and technologies used for impregnation and lamination.
We are happy to partner with our customers to continuously improve their processes by resin development.
About Resins
Metadynea Austria has decades of experience in adhesives for the woodworking and the paper saturation industry. We have know-how in different kinds of binders but most expertise we have gained in formaldehyde based resins. This knowledge is applied in our advanced industrial resin production.
High level of automation and the possibility to precisely adjust every batch results in high quality resins with a high stability of parameters from batch to batch. Thus, our customers are able to work without any adjustments in their process from one delivery to another.
Our plant laboratories are equipped with the most modern tools to make precise measurements not only to fulfil the standard requirements but also to follow and control non-standard quality parameters of resins like real-time monitoring of resin parameters during synthesis.
Metadynea’s R&D center in Krems has the most modern analytical equipment and application equipment that allows us to test resin properties and to simulate industrial processes.
Metadynea Austria continuously develops its products to maintain the leading position in our markets. We constantly invest in the improvement of existing processes and in the development of new resins.
MF Impregnation Resins
Melamine-Formaldehyde (MF) resins are aqueous solutions of rather low molecular condensation products of melamine and formaldehyde, in many cases modified with certain functional additives to achieve certain properties while processing or in the finished product (e.g. furniture, laminate floor).
Typically, MF resins are used as saturating resins for paper. Herein, the liquid resin penetrates into the paper. Shortly thereafter the paper is dried at elevated temperature. In this step the resin is condensed further. This continued condensation is carried out under heat and pushed forward by a hardener system.
Then the impregnated paper is taken into a hot press and pressed e.g. on top of a particle board. If the curing is done completely a paper-polymer composite is produced. The resulting material possesses superior surface properties like high thermal stability, optical properties (transparency), resistance against water, water steam and various chemicals and surface hardness.
Decorative, backing and overlay papers (also fortified), filled with melamine resin, are used for direct lamination on particle boards or similar for the furniture and flooring market as well for boards decorated with HPL and CPL, used in applications with heavy demands on chemical and mechanical resistance and hygienic properties of surfaces, e.g. kitchen, lab, hospitals, etc.
Metadynea’s MF resin portfolio contains various resins of 52 – 68% solid content which are characterized by excellent penetration properties and a colorless and clear appearance.
UF Impregnation Resins
Urea-Formaldehyde (UF) resins are aqueous solutions of low molecular condensation products of urea and formaldehyde. As a consequence of their chemical nature, UF resins show higher susceptibility to hydrolysis and a lower heat resistance as MF resins. Generally speaking, and due to cost advantages compared to MF resins, UF resins are used either pure or in blends with MF resins in two stage impregnation processes for saturating the core of the decorative paper prior to coating with MF resins (e.g. for furniture production).
Typically UF resins are used for the production of paper based finished foils, pre-impregnated papers and sometimes for edge-banding materials. Depending on the final application, the UF resin is blended with acrylic emulsions.
Metadynea’s UF resin portfolio contains various resins of 50 – 60 % solid content, and which show excellent penetration properties, a clear and colourless appearance. The portfolio is rounded up by low emission resins, enabling our customers to produce low formaldehyde emitting surfacing materials.
Etherified MF Resins
Etherified MF resins are predominantly aqueous solutions of low molecular condensation products of melamine and formaldehyde. During their production, the formed melamine methylols are etherified by alcohols. Depending on the adjusted degree of etherification either partly or completely etherified MF resins are obtained. For etherification most of the times methanol is used but other alcohols are applied, too. The etherification is carried out in an acidic pH range and is competing with the further self-condensation of the melamine methylols. The self-condensation leads to unwanted oligomers instead if the parameters for etherification aren’t adjusted carefully. The oligomers themselves can have a strong impact on the resin poperties, such as reduced water dilutability, higher viscosity, reduced penetration speed, and a wrong reactivity. Etherified MF resins are usually less reactive as regular MF resins and thus have a significantly longer shelf life.
Depending on their final field of application etherified MF resins are used either as such or functionalized by the incorporation of additives such as flexibilizers.
Non-modified, partly methylated MF resins are used e.g. as wet strength agents in the production of specialty papers like overlay, grinding and pasting papers. Prior to its use as wet strength agent the resin is diluted and activated by acids. Another application of such resins is as binder for production of glass fleeces.
Partly etherified MF resins containing additives are typically used for the production of edge banding materials, finish foils and extremely flexible impregnated papers (e.g. wrapping papers). Usually the incorporated additives are plasticizers and acrylic emulsions. Application areas of such products are decoration of wood based panels and deliver products complying with highest optical and technical demands.
Furthermore, partially methylated melamine resins can also be used directly for the surface treatment of cardboard or paper. They improve the wet strength of the surface, the picking and splitting resistance and provide dimensional stability. Further areas of application include the formulation of paints and textile finishing. Partially methylated urea resins are also used for these two applications.
Our portfolio of partly etherified MF resins contains various products of 52 – 75 % solid content either with or without further modifications. The resins have excellent penetration properties, and are of clear and colourless appearance. Additionally the resins are designed for low and lowest formaldehyde emissions, both during conversion in the mill and in the final product applications.
Do you have further questions?
Send an email to resins(at)metadynea.com or use our contact form. We are looking forward to your message!