Wheatpaste
Paste adhesives are in the form of an aqueous Quellungsproduktes from starch or organic cellulose ethers. Usually it is methyl cellulose. They consist of 2-20 % of renewable material and 80-98 % water. Glue binding by evaporation of water from physically; they are cold -curing ( s cold glue ) and easy to process.
Properties / types
Paste form even at the lowest concentrations, a highly viscous, non- stringy mass. Due to the various types of wallpaper industry offers various types of wallpaper paste, sometimes with widely different properties. Decisive for the selection of the paste are the processing instructions of the wallpaper manufacturers that are entered in the depositor roll of wallpaper.
Commercially paste are mainly offered in powder form as normal or special paste:
Quality differences
Since 1953, there are high-quality wallpaper paste from the materials based on natural substances methyl cellulose and starch. Both are non-toxic and are also often mixed with resins and other substances that facilitate the application, make the wallpaper paste stronger or more durable. Wallpaper paste, which have a very low or no methyl cellulose content, but strength as the main ingredient can be produced cheaper. This reduces bond strength and the total liability. Also, because the resin content is frequently low, usually reduced with lesser-quality wallpaper pastes the initial adhesion and the wet strength during the subsequent coat.
Areas of application
- Glue is used for gluing wallpaper, it can, however, only water vapor permeable wallpaper stick with it. Impermeable to water wallpaper as metal foil or vinyl wallpaper at little to non-absorbent substrates allow the water vapor from escaping, the paste will not dry and therefore do not exert its adhesive strength.
- In the bindery is also used as an adhesive paste.
- Starch paste, mainly from potato starch is used heavily in the production of corrugated board.
- For the production of paper mache paste is used as a binder.
- In the street art ( street art ) glue is used to attach pre-fabricated and cut- works (so-called Cutouts ) used on walls.
- As a coupling agent in the manual ultrasonic testing
- From Meyers Lexicon:
" Glue ( bookbinding glue ) adhesive for bookbinding is obtained from wheat starch by with a little cold water touches the same to a pulp and this poured with vigorous stirring in a thin stream into hot water until the same has assumed the proper consistency. Cooking may be the glue not because he then easily jump off after drying. The paste is pure cold processed or, if, in order to increase its bond strength, mixed it with some glue water, lukewarm. For coarser work is prepared paste made from rye flour, and if you mix the still hot paste with half the weight of the applied starch or flour turpentine good, so the glue adheres better, resists moisture and is ideal for sticking the new wallpaper on old. To make the paste more durable, is dissolved in the water, with which it brews the strength, the 16th part of the weight of the latter alum or mixed on the final, cold paste with a little creosote or gasoline. To prevent insects from the crafted with glue stuff, boiled the water with a little aloe, wormwood or gourds. "
Application
Start
Wallpaper paste is mainly available as a powder. The application of this into a vessel with clean, clear water ( not mineral water ) is stirred, also called " start ". As Anmachgefäß any suitable clean and rust-proof container. Most suitable are cylindrical container, as this can better be stirred. What is the relationship must be powder and water are mixed, the processing instructions can be found on the package. It is important very quickly to pour the wallpaper paste into the water, as it can clump otherwise. Then the wallpaper paste has - depending on paste type - swell some time.
Soaking time
The soaking time refers to the amount of time the wallpaper paste must be left before wallpapering on the wallpaper to soak them. The soaking time differs depending on the strength and quality of the wallpaper paper notes are indicated in the depositors of the roll of wallpaper. The soaking time should be approximately the same length over all paths, since different times can cause soft pattern shifts. By soaking the wallpaper expands significantly from in width, it changes its dimension. Adhesive is dried after the application of the wallpaper on the wall, a tight connection between the wall and wallpaper is prepared. Since trying the wallpaper during drying to contract again, it comes to the so-called drying voltage by which the wallpaper has the desired tone and bubble- free fit on the wall. Non-woven wallpaper is not made of paper and remain dimensionally stable even after exposure to moisture. Therefore, this Tapetenart must not depart. This also makes it possible to coat the substrate with glue or roll curl and dry the fleece wallpaper paste into the bed.
Storage
Up mixed paste can be, depending on the environmental conditions, usually keep up to 14 days if they are covered. Exception are normal paste. For a mold growth during storage of pastes benzalkonium chloride, may be added as a preservative.
Glue stains
Dried glue are delicate surfaces only very tedious, sometimes even impossible to remove, leaving a striking gloss effect against the light. If wallpaper paste during papering get to the front of the wallpaper, but it can be dabbed with a damp cloth and clear water.
Removing wallpaper
Old wallpaper can be removed with so-called and wallpaper from the wall. Quality non-woven wallpaper, which were bonded with high quality non-woven wallpaper paste, can be dry stripped from the wall for many years.
History
For centuries been used in the painting and decorating craft so-called bone glue for wallpapering. 1888 developed the painter and decorator Ferdinand Sichel the first ready-made wallpaper paste based on vegetable starch and made the bone glue unnecessary. For the " Sichel wallpaper paste SM " had to be diluted and stirred prior to processing only with hot water. Beginning of the 1920s, took over the production of sickle developed by Dr. Friedrich Supf cold water soluble starch paste in dry form, also referred to as the source strength. In 1953, Henkel under the trademark Metylan a new wallpaper paste on the market, which consisted of pure methyl cellulose. The white cellulose powder is immediately absorbed by the water, does not clump, forming in a few minutes, a homogeneous solution with strong consistency. Due to the ease of processing ability, high adhesion and resistance to lime and cement the new wallpaper paste superseded all previous paste methods. Since 2002, there are some wallpaper paste in the low-dust granules. 2010 Henkel developed the first wallpaper paste, which is stirred in as a liquid concentrate in water. This could be a lump-free mixing and rapid use skill to be achieved.
Sustainability
From an environmental, occupational hygiene and health point of view there is no better adhesives as pastes. The application is however limited to the listed areas.