Patent GB-644958-A (GB)
Title: Improvements in and relating to the hardening treatment of casein or the like protein fibres
IPC: D01F4/00
Filed: 1948-07-21
Abstract: <PICT:0644958/IV (a)/1> The process of the parent Specification for treating a tow of casein or like protein fibres with a hardening liquid of specific gravity greater than that of the fibres is modified in that the convolutions of the tow lying on the surface of the accumulated mass of tow within the bath are continuously sprayed with hardening liquid so that the mass of tow floating on or in the liquid is uniformly impregnated with the hardening liquid throughout the hardening treatment.  Preferably, hardening liquid is also sprayed on to the tow just before it is laid on the surface of the accumulated mass in the bath.  The spraying device may be attached to the device for feeding the tow into the bath. This device may traverse the bath while oscillating in a direction at right angles to the direction of traverse.  The hardening liquid which is sprayed on to the tow may be continuously withdrawn from the liquid in the bath and it may be heated so that when applied to the tow it is 3-6 DEG C. higher than the temperature of the bath.  Crystallization of salts on the tow is thus prevented.  If the tow is taken from a bath containing sodium sulphate and is being fed to a bisulphate hardening bath, sulphuric acid may be added to the withdrawn liquor before it is sprayed on to the tow.  The treatment may be applied to milk casein or to vegetable casein or globulins such as those derived from soya beans, peanuts, and the like.  As shown, a tow of casein fibres passes round godets 2, 3, 4, carried by a traversing and oscillating bar 5, and is then fed in sinuous convolutions 6 on to the surface of the hardening liquid 7.  The bar carries a feed pipe 9 which sprays hardening liquid on to the tow.  The tow is continuously removed from the underside of the mass of convolutions.  A shaft 11 has a double helical traversing screw 14 which is keyed into the bar 5 so that on rotation of the shaft the bar is traversed.  Shaft 10 drives godets 2, 3, 4, through sprocket mechanism.  Shafts 10, 11 and bar 5 are oscillated by means of rocking arms 15, 16 which are pivoted on rods 23, 24, and rocked by rods 25, 26.  These rods are oscillated by means of pins on rotating wheels, the pins working in vertical slots in enlargements of the rods.  In an example, a tow obtained by extrusion of milk casein into a formaldehyde - sodium sulphate - aluminium sulphate bath is fed into the hardening bath which contains a solution of formaldehyde and sodium and aluminium sulphates at 50 DEG  C.  The surface of the mass of convolutions in the bath is sprayed with liquor from the bath but heated to 53 DEG  C. In another example, tow treated as in the first example is fed into a further hardening bath containing sodium bisulphate, sulphuric acid, aluminium sulphate, and formaldehyde at 40 DEG  C. and the surface convolutions are sprayed with a liquid obtained by mixing sulphuric acid with liquid withdrawn from the bath, the temperature being raised to 43 DEG  C.ALSO:<PICT:0644958/IV (c)/1> The apparatus used in the process of the parent Specification for treating a tow of casein or like protein fibres with a hardening liquid of greater specific gravity than that of the fibres is modified in that means are provided for spraying with hardening liquid the convolutions of the tow lying on the surface of the accumulated mass of two within the bath.  Hardening liquid is preferably also sprayed on to the tow just before it is laid on the surface of the accumulated mass in the bath.  The spraying device may be attached to the device for feeding the tow into the bath.  This device may traverse the bath while oscillating in a direction at right angles to the direction of traverse.  The hardening liquid which is sprayed on to the tow may be continuously withdrawn from the bath, and it may be heated so that when applied to the tow it is 3-6 DEG  C. higher than the temperature of the bath.  As shown, a tow of casein fibres passes round godets 2, 3, 4 carried by a traversing and oscillating bar 5, and is the fed in convolutions 6 on to the surface of the hardening liquid 7.  The bar carries a pipe 9 which sprays hardening liquid on to the tow.  The tow is continuously removed from the underside of the mass of convolutions.  A shaft 11 has a double helical traversing screw 14 which is keyed into bar 5 so that on rotation of the shaft the bar is traversed.  Shaft 10 drives godets 2, 3, 4 through sprocket mechanism.  Shafts 10, 11 and bar 5 are oscillated by means of rocking arms 15, 16 which are pivoted on rods 23, 24 and rocked by rods 25, 26.  These rods are oscillated by means of pins on rotating wheels, the pins working in vertical slots in enlargements of the rods.