AT86756B

AT86756B - Process for the production of alkali cellulose.

Info

Publication number: AT86756B
Authority: AT
Inventors: Carolus Lambertus Stulemeyer
Original assignee: Carolus Lambertus Stulemeyer
Priority date: 1920-01-30
Filing date: 1920-01-30
Publication date: 1921-12-27

Description

  

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  Verfahren zur Herstellung von Alkalizellulose. 



   Es ist bekannt,. dass bei der Herstellung von Viskose, die zur Erzeugung glänzender Fäden, Bänder, Films, Platten usw. dienen soll, die Behandlung der Zellulose mit Alkalilauge einer-der wichtigsten Teile des Prozesses ist. Eine schlecht mit Alkalilauge durchtränkte Zellulose ergibt mit ungelösten Zellulosefasern verunreigte Viskose. Die ungelösten, durch Alkali'gelatinierten Fasern erschweren das Filtrieren solcher Viskosen ausserordentlich, ja sie machen es sogar oft unmöglich. Unfiltrierte Viskosen lassen sich aber nicht in gewünschter Weise weiterverarbeiten, z. B. zu Fäden verspinnen. 



   Es wurde nun gefunden, dass die Ursache des schlechten Eindringens der Alkalilauge in die einzelnen Fasern und deren Zellen, die Luft ist, die ausserordentlich schwer durch Alkalilauge verdrängt wird. Deswegen wird in der Praxis die Zellulose längere Zeit, wie etwa   i   Stunden, mit der Alkalilauge behandelt. 



   Dieser grosse Übelstand wird der Erfindung gemäss, dadurch vollständig behoben, dass man die Zellulose vor der Behandlung mit Alkali möglichst luftfrei macht   und-zweckmässig   auch die Behandlung selbst unter vermindertem Druck ausführt. 

**WARNUNG** Ende DESC Feld kannt Anfang CLMS uberlappen**.



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  Process for the production of alkali cellulose.



   It is known,. that in the production of viscose, which is to be used to produce shiny threads, ribbons, films, plates, etc., the treatment of the cellulose with alkali is one of the most important parts of the process. Cellulose that is poorly saturated with alkali lye results in viscose contaminated with undissolved cellulose fibers. The undissolved fibers gelatinized by alkali make the filtration of such viscose extremely difficult, indeed they often even make it impossible. However, unfiltered viscose cannot be further processed in the desired manner, e.g. B. spin into threads.



   It has now been found that the cause of the poor penetration of the alkali lye into the individual fibers and their cells is the air, which is extremely difficult to displace by the alkali lye. Therefore, in practice, the cellulose is treated with the alkali for a long time, such as 1 hour.



   According to the invention, this major drawback is completely eliminated by making the cellulose as free from air as possible before the treatment with alkali and, expediently, also carrying out the treatment itself under reduced pressure.

** WARNING ** End of DESC field may overlap beginning of CLMS **.

Claims

The great advantage of the process over the known methods is that the process can be carried out about three times as quickly, but especially that the viscose obtained from celluloses treated in this way is evenly saturated with alkali and therefore does not contain any undissolved fibers. The viscose obtained in this way can be nitrided very easily as a result, PATENT CLAIM: Procedure for. Production of alkali cellulose, in particular for the purpose of viscose preparation. characterized in that the cellulose is made as free of air as possible before the mercerization process (dipping in alkali lye) and it is also expedient to carry out the treatment with alkali itself under reduced pressure. ** WARNING ** End of CLMS field may overlap beginning of DESC **.