Lamination

As laminate ( from Latin lamina " layer " ) refers to a material or a product consisting of two or more surface layers bonded together. These layers may consist of identical or different materials. The preparation of a laminate is referred to as laminate.

There are generally two reasons for the preparation of a laminate:

• Combination of different materials, so that the finished laminate combines the properties of all the components in it, for example, Floor coverings in which a fixed and affordable pad with a visually appealing cover layer ( usually wood imitation) is glued to the floor;
• Identity cards, in which a printed card is glued as an information carrier between two protective plastic film.

• In the manufacture of components made of fiber-reinforced plastics, which are made ​​thicker at stress points higher, and in which the fiber direction is chosen according to the load direction;
• In the manufacture of plywood, in which each individual layer of wood can be examined before gluing on any damage or growth failure.

Laminate floor covering as

Laminate floors mimic the look of a high-quality floor covering (mostly hardwood ), however, consist of a low-cost carrier layer which is sealed with a thin decorative layer and decorated. Such a floor is to be laid very inexpensive and easy ( compared for example with parquet or tiles).

Laminate floors are available in various panel thicknesses and with different abrasion resistance (service class ). Cheaper laminates are relatively thin, have a relatively simple decor and are more susceptible to abrasion and moisture ( especially in the abutting edges between two panels ). High quality laminates imitate contrast with textured embossing ( to simulate a wood grain surface ) and V - joints between the panels very realistic the look of a real wood floor. Elaborate surface sealers allow the use of laminate on heavily loaded floors such as in nightclubs.

However, all laminate floors have a common drawback: the case of damage or wear of the surface they can not grind like a solid wood floor because of the decorative layer, the support material would be exposed immediately.

Laminates of fiber-reinforced plastics

Laminates of fiber-reinforced plastics are strong, lightweight and free customizable materials from embedded in synthetic resin fibers. They are used in aerospace, automotive and boat and in many other areas where high strength and lightweight materials are needed.

A distinction laminates according to several criteria:

On their structure

• Fully laminated, so massive version: The component consists entirely of fiber- reinforced plastic. Such laminates are relatively heavy, but less sensitive to point loading, and easier to manufacture in tight radii.
• Sandwich laminate: Between two layers of fiber reinforced plastic laminate an intermediate layer of, for example, wood, foam or Nomex weave is inserted. This intermediate layer makes the overall component significantly thicker (and therefore stiffer ), but also weigh considerably less than a stiff intermediate layer of full- laminate. They are usually much lighter than solid laminates, but through the soft core susceptible to puncture and point load.

After the material of the fibers used, usually

• Fiberglass laminate (GRP): inexpensive, readily available, transparent in thin layers. The fibers are resistant to UV light.
• Carbon fiber laminate: very light and strong, but expensive. Electrically conductive and sensitive to impact. When using appropriate tissue results in a visually attractive surface (so-called " point of view coal ").
• Kevlar laminate: relatively insensitive to impact and point loading. Vibration damping and electrically insulating. The fibers are UV - sensitive and can absorb moisture.

• Fibrous materials for fiber-reinforced plastics

Kevlar fabric

After the alignment of the fibers used

• Unidirectional laminate: the individual fiber layers run in only one direction. The fibers are very stretched and tensile forces can absorb very well. The individual layers are usually oriented in different directions in order to accommodate loads in various directions. The strength in any direction is very accurately defined.
• The fabric laminate of: consists of a fabric of fibers. The fibers are woven together, and thus have the warp and weft threads. While the weft threads are straight, the warp threads are woven through by them. The warp threads can stretch under load so, therefore, the laminate is less stiff in the warp direction.
• Fiber mat laminate: the fibers are superimposed disordered. Since the fibers are not stretched, such a laminate is less rigid than those mentioned above.
• Spray " laminate ": This material is not actually a laminate because no defined layers are applied. Instead resin is incorporated with a spray gun in a mold, with short (up to several centimeters long ) fiber pieces are added. The short and disordered fibers and the very high resin content provide poor strength values ​​and high tendency to microcracks that weaken the material further. In addition, it is impossible to control the applied layer thickness accurately. Advantageously, only the very low-cost production.

After the material of the resin used ( as a matrix for holding and fixing of the fibers ), usually

• Polyester resin: inexpensive and easy to apply. Hardens quickly, but is relatively brittle and tends to form microcracks. Surfaces of polyester resin are very smooth and shiny, so they are well suited for decorative surfaces or mold.
• Vinyl ester resin: high quality, but also more expensive than polyester. Less brittle.
• Epoxy resin: expensive and relatively complex in processing. Long cure times allow long processing, but also require much time. In order to achieve high strength is often a well-defined post-curing at an elevated temperature (so-called annealing ) is required. Very flexible and high strength, excellent adhesion properties.
• Phenolic resin: very heat resistant, making it suitable for high temperature applications such as brake pads or heat shields.

HPL ( High Pressure Laminate ) and CPL (Continuous Pressure Laminate )

Early on after the development of the first synthetic resins, it was discovered that this an excellent way of pressing inexpensive materials such as paper, paperboard or textile fibers into flat sheets, which in turn could well to production of thicker laminates themselves. To several impregnated with melamine and phenolic resin paper under pressure and temperature and are pressed together with a covering layer. These materials are available as HPL (short for High Pressure Laminate ) known, but are also named with the brand name as Dekodur, Duropal, Resopal or Sprelacart. By using heat-resistant resins keep the finished boards to high temperatures (eg, cigarette ash and hot pot soil) was for a short time without taking damage. The surfaces are easy to maintain and clean, light- resistant, odorless and resistant to alcohol, organic solvents and water.

HPL is used in many everyday products because of the scratch resistance and the diversity that can be generated by different printed papers. Table tops, door panels, furniture and kitchen tops are just some of the more common applications. If it does not depend on a high shock resistance, or the coating to the contours of the material to follow, support plates can be provided with a direct coating. Then, for example, two impregnated with melamine resin paper or a so-called finish film are pressed directly with the carrier material.

A marketed as an environmentally friendly version of HPL are listed at market ECO HPL laminate panels. These are primarily molded from recycled paper made ​​without the use of artificial and phenol-formaldehyde resins.

CPL plates ( Continues Pressure Laminate ) are pressed in a continuous or continuous process in two -sided heating roll belt presses in a kind of endless panel. The pressing pressure is less than HPL.

In German-speaking countries, these laminates are also " Decorative laminate sheets " called (according to DIN abbreviated DKS = Decorative plastic laminate ) or " decorative laminate ".

The use of special materials, an increased resistance to flame effects can be achieved. A heat dissipating layer, for example, a metal foil which makes the plate resistant to cigarette burns, by the heat is quickly dissipated.

Various disk properties such as Zug-/Biegefestigkeit, abrasion resistance, scratch and stain resistance, behavior to cigarette burns, hot cooking pot bases, boiling water, etc., are governed by test standards.

For postforming panels used papers and resins allow for a subsequent softening of the impregnation, since the crosslinking of the plastic molecules is initially not yet been completed. As deformation by the action of heat and pressure is possible to adhere the laminated sheet, for example, the rounded edges of the reinforcing material around.

Wood-based materials

Many well-known wood-based materials are also laminates, including, for example,

• Plywood with its sub- types such as multiplex boards.
• Countertops and furniture fronts, in which a particle board with a protective plastic decorative layer is glued.
• Formverleimtes plywood, here the individual layers of veneer plywood are glued not on a flat surface, but the same in the prescribed form. This allows you to produce relatively complex shapes made ​​of wood.
• Kaltverleimtes of laminated wood, which is similar to formverleimtes plywood of many layers of wood bonded at room temperature. Here, however, the grain runs in all layers in parallel, so that the created form part has characteristics similar to a piece of solid wood that is grown in the same shape. On the Block ( twisting of the layers to each other) are not usually for aesthetic reasons.
• OSB panels (also called OSB ) are not strictly be described as laminates, as they not defined layers (Latin: laminae ) are constructed.

• Various laminated wood materials

Multiplex board

Chipboard with and without laminated decorative layer

A chair made ​​of laminated plywood

Kaltverleimtes molded plywood

OSB board

Laminated steels

Damascene consists of several layers each verschmiedeten steel, so that in the finished product is formed by a pattern of the steel types used. Because even here several layers are connected to each other, one also speaks of laminated steel.

Sealing of printed products

In this context, lamination refers to the welding of documents, photographs or similar printed material between two transparent plastic film (polyester film ). This plain paper from moisture, wrinkles and damage is protected, also manipulation more difficult, and labels can be easily removed when required. The laminating pouches are usually called as pouches or in the service sector as roles that are processed over large laminating machines sold. The pouches are half-folded, so documents can be easily aligned straight. There are different thicknesses of laminating pouches. The data are usually in micrometers ( often referred to as μ, Mic, Wed or Mü called ) and refer to a " half" of the film. In a statement, for example, " 80 Mic " is the thickness of a laminated document is 160 microns plus the thickness of the paper. There are two types of processing:

• Heat lamination: Here, the paper is inserted into the slide and guided in a laminator with a hot roll, the both layers of plastic fused at about 60 ° to 120 ° C to each other by heat and pressure.

• Cold lamination: This is located in the foil pouch, an adhesive that is already glued together by pressure. Cold lamination can therefore be carried out without special equipment by hand.

Other use of the term " laminate "

• Unilateral protective lamination of printed works with adhesive films, mostly in the outdoor area for information boards and the like for protection against weather, UV light or vandalism such as graffiti.
• Laminate sail from high strength fibers that are fused and protected on both sides of sheets or layers of fabric.
• Textile laminates, in which a water vapor-permeable ( " breathable " ) membrane layer is adhered to cover layers to protect the membrane from damage.