Method for obtaining viscose filament rayon with cyclically varying linear density called "flame" rayon, an installation for the realization of this method, and a product, obtained using this method and this installation

Abstract

When to the spinning machine one or two individual installations for dying are joined suggested method allows production of dyed in one or two colours filament rayon with cyclically varying linear density.

1 . A method for obtaining viscose filament rayon with cyclically varying thickness, including the following stages: mercerization of initial pulp i.e. processing with a concentrated solution of sodium hydroxide, resulting in alkali cellulose, which afterwards undergoes the process of destruction to decrease the cellulose degree of polymerization, followed by temperature reduction and dosing of the alkali cellulose amount for the production of one batch of viscose; carbon-disulphide treatment which causes the alkali cellulose to transform into cellulose xanthate; the cellulose solution of one batch is then mixed and homogenized with the one from the previous and the following batch and deaerated, filtered to remove the impurities; then the viscose solution is fed for spinning to the spinning machine, as the viscose solution coming out from the spinnerets enters the spin bath where as a result of the chemical reactions in course transforms into filament fibres which are passed through spinning devices to a centrifuge at each working position in order a rayon cake to be formed;
 With the main characteristic that the spinning is performed by interrupting the synchronization of the viscose solution supply to the spinnerets of spinning machine and the takeover of the freshly-spun in the spin bath filament rayon by separately actuating of the first and the second spinning devices and the rayon arranging in centrifuge device using the existing first power feeding installation, and separately actuation and control of the power shaft and viscose dozing pump joined to it by using new second power feeding installation, run by a control unit (inverter) thus carrying out a programmed change of the quantity of the supplied for spinning viscose independently from the operation of the first and second spinning and etc., devices of the spinning machine.   
     
     
         2 . A method for obtaining dyed in mass viscose filament rayon with cyclically varying thickness/linear density according to  claim 1 , with the main characteristic that viscose solution before spinning is mixed with preliminarily prepared pigment suspension from one of a couple of dispersed in water organic pigments prepared as pastes; homogenization of the mixture, which is passed for the same way of spinning as  claim 1  and all other stages of the above-described processes. 
     
     
         3 . A method for obtaining bicolour dyed in mass viscose filament rayon with cyclically varying thickness/linear density according to  claim 1 , with the main characteristic that to the spinning machine are added two independently operating installations for dying in mass by the use of which viscose solution before spinning could be coloured by two preliminary prepared different in colour pigment suspensions. By the use of two homogenizers and two local viscose pipe collectors to the neighbour working positions of spinning machine at the same time could be supplied differently coloured viscose solutions for spinning. After spinning differently coloured freshly spun filament fibers from these two working positions are transferred to the first working position centrifuge only by the use of first and second spinning devices of the same first working position. After spinning as  claim 1  freshly spun bicolour filament rayon with cyclically varying thickness is passing through all other stages of the above described processes. 
     
     
         4 . An installation for the production of viscose filament rayon with cyclically varying thickness, added to the existing spinning machine part of which are local viscose pipe collector ( 38 ) to which a range of working positions are joined each one supplied with viscose solution dozing pumps, power shaft actuating viscose dozing pumps, first and second spinning devices ( 27 , 28 ), an arranging system ( 39 - 5 ) by which freshly spun filament rayon is transferred from second spinning device ( 28 ) to the centrifuge ( 29 ) where freshly spun cake is obtained, two electric motors  40 - 1  and  40 - 2  powered by electricity from first feeding unit  40 - 4  and actuating as follows: first electric motor  40 - 1  through the first reduction gear  39 - 1  and a gear transmission system  39 - 3  is connected for actuation of first  27 - 1  and the second  28 - 1  spinning devices as the second electric motor ( 40 - 2 ) is actuating the arranging device  39 - 5  with the main characteristic that a second power feeding installation is added consisting of a third electric motor ( 40 - 3 ), powered by electricity from the second feeding unit ( 40 - 7 ) and connected to it a new control unit ( 42 —controlling inverter system), as the third electric motor through an additional reduction gear group ( 39 - 2 ) is actuating the power shaft ( 21 ) only and the viscose solution dosing pumps ( 22 ) both work of which is controlled by unit ( 42 ) according to the preliminarily set into this unit program operating range of changes of the power shaft ( 21 ) and viscose dozing pumps; / 22 /revolutions, independently from the operation of the all other devices. The spinning on the spinning machine ( 10 ) is followed by all other stages of the above-described processes from washing unit ( 12 ), till a storage unit ( 19 ). 
     
     
         5 . An installation for the production of dyed in mass viscose filament rayon with cyclically varying thickness according to  claim 2 , with the main characteristic that to the spinning machine ( 10 ) an individual installation for dying in mass ( 10 - 1 ) is joined, including a storage tank for a preliminarily prepared pigment suspension ( 30 ), a suspension dosing pump ( 31 ), a homogenizer ( 32 (connected to the local viscose pipe collector of the spinning machine, to which are joined a range of working positions. Power shaft and all other spinning devices actuating is arranged in accordance with scheme described in  claim 4 . 
     
     
         6 . An installation for the production of bicolour viscose filament rayon with cyclically varying thickness according to  claim 3 , with the main characteristic that to the spinning machine ( 10 ) are joined two individual installations for dying in mass ( 10 - 1 ), with two storage tanks for preliminarily prepared pigment suspensions ( 30 ), including two suspension dosing pumps  31  and two homogenizers  32  connected through two local viscose pipe collectors to one spinning machine with joined to them a range of working positions. The actuation of viscose dozing pumps independently to which viscose pipe collectors are joined is arranged by one and the same power shaft ( 21 ) which operation follows the scheme described in Clam  4 . 
     
     
         7 . Viscose filament rayon with cyclically varying thickness/linear density obtained following the method and installation as described in  claim 1 . 
     
     
         8 . Viscose filament rayon dyed in mass with cyclically varying thickness/linear density obtained following the method and installation as described in  claim 2 . 
     
     
         9 . Bicolour viscose filament rayon with cyclically varying thickness/linear density obtained following the method and installation as described in  claim 3 .