Mechanical process, wet or dry, to obtain continuous changes in appearance and color of textile fabrics using rollers coated with diamond powder

Mechanical process, rollers and machines (10) for obtaining continuous modification of the appearance and color of textile fabrics by passage, dry or wet, of the fabric (41) under tension, around rollers (23-26) with a coating (35) of diamond powder, uniformly or in areas marked out in their surfaces.

The invention concerns the processes, machines and equipment for changing 
the appearance and colour of textile fabrics to secure effects some of 
which may be special. 
Machines and processes for altering the appearance and colour of fabrics 
generally are well known in the trade. 
These changes may be brought about by chemical or mechanical methods. 
If the process is mechanical the machines used are those for lapping or 
finishing; they comprise lapping rollers, generally working dry, around 
which a fabric, stretched under tension, is passed by unwinding it from 
one roller and winding it, after lapping, onto another. 
The lapping rollers have an abrasive coating, the type of grain used being 
decided by the desired result. 
The coating consists of abrasive granules fixed onto a suitable support. 
If the process is chemical the methods used are limited in the effects they 
produce and may damage the fabrics. Mechanical methods using rollers 
coated with abrasive granules raise many problems because of low 
efficiency, of the need for frequently redressing the abrasive layer, of 
the unevenness of results and because of obtaining effects which often are 
not those required. 
Purpose of the invention is to provide a process for wet and dry lapping or 
finishing which offers considerable advantages compared with present 
processes both because of the effects obtained on all types of textile 
fabrics and because of its high production efficiency as will be explained 
below. 
Subject of the invention is a process for continuous modification of 
surface appearance and colours on fabrics generally, in which process the 
fabric passes, stretched under tension, round a set of lapping rollers, 
the working surfaces of which carry a coating of diamond powder. 
The diamond powder is applied to the surface of the roller by 
electrodeposition. 
Shapes and sizes of the granules forming the diamond powder are chosen 
according to the desired abrasive action. 
The fabric can be treated dry or wetted. For wet treatment, before its 
passage round the abrasive rollers, the fabric passes through a bath of 
liquid. The liquid may be water or may contain substances which, combined 
with the abrasive action, produce special effects on the treated fabric. 
The working surface of the rollers may be divided up into areas of 
different shapes and sizes with intervals between one such area and 
another making the abrasive action more powerful due to the edges, which 
may be sharp,of the areas raised in relation to the spaces,facilitating 
discharge of particles removed and easier distribution of the liquid if 
the fabric is being treated wet. 
The spaces may be strips with no diamond powder or even grooves in the 
surface of the rollers, with or without diamond powder, according to 
circumstances and preferences. 
Also as circumstances require, the strips or grooves may be longitudinal or 
annular, placed at the same or different centre distances, the purpose of 
this being to produce on the fabric treated areas separated from untreated 
areas. The strips or grooves may be one or more halical pairs. 
These pairs may lie in opposite directions and cross over. This produces 
excellent discharge flows of detached particles or dispersion of liquid if 
the treatment is wet. The strips or grooves may be partly longitudinal and 
partly annular, freely crossing one over another. Some rollers are 
motor-driven. 
The number of rollers coated with diamond powder around which the fabric 
passes, and similarly the speed of one or other of the rollers,may be 
varied at will according to the effects it is desited to obtain. 
The direction of rotation can be reversed for some or all rollers according 
to previously set stages of work. Clearance angle between fabric and 
rollers may be varied in accordance with the results to be produced. 
Fabric tension can be varied as preferred to obtain that which is most 
suitable for the purpose. 
The speed at which the fabric moves can also be varied. Action of the 
diamond coated rollers can be simultaneous on both sides of the fabric. 
All working parameters chosen can be memorized in an electronic programmer 
so that they can be repeated. 
The foregoing clearly shows that the present invention gives rise both to a 
new process, to new rollers and to new machines which, with the new 
rollers, make possible a new process. 
The invention offers evident advantages. 
The use of rollers coated with diamond powder permits an excellent 
treatment to be given with maximum output efficiency, maximum variety of 
action on all types of textile fabrics, and offers the possibility of 
repeating as desired the effects that have been programmed. 
Processing can be not only dry but also wet causing no furring, and can be 
carried out on dyed and printed fabrics, on denim types and all done 
without chemicals. Any type of fabric can be treated, thin or thick, of 
natural or synthetic fibres, cotton, wool, viscous, linen, polyester, 
polyammide, cupro/rayon, nylon, imitation leather and every other type 
used. 
Processing can be carried out simultaneously on both sides of the fabric. 
Maximum consistency of effects over time is assured, as coaxiality of 
granules ensured by diamonds over the whole length of the lapping rollers, 
remains unaltered until completely worn down, within three/four hundredths 
at least. 
Overall efficiency of the machine whose rollers have a diamond granule 
coating, is several times greater compared with present methods using 
common types of abrasives. There is no need for the redressing generally 
required. The possibility of using the best number of lapping rollers to 
suit the work required, gives a very high output and greater effects made 
possible by the fact that the rollers can also move in the transversal 
direction. 
To sum up these advantages the strong and steady abrasive power of diamond 
powder realizes dry or wet lapping able to produce any effect desired on 
any textile fabric at a rate of output decided at will according to 
quantities required. This applies not only to a uniform all-over treatment 
of the fabric but also to the unlimited possibilities of patterns between 
treated areas, untreated areas and others treated differently, all due to 
what can be achieved with diamond powder coated rollers in which there is 
a variety of strips and grooves.

The lapping machine 10 for textile fabrics comprises the base 11 with 
initial support 12 to sustain the rotating roller 13 on which is wound the 
roll 40 of fabric 41 to be treated. 
Having passed a set of transmission units 14 and a bath of liquid, the 
stretched fabric passes through the set 20 of four lapping rollers 23-26 
after which, treated and wrung out, it winds onto the roller 15 on the 
support 16 where it forms the roll 42 of treated fabric. 
The lapping rollers like 26 in FIG. 3 comprise a metal tube 30 supported at 
its ends by drums 31 and 32. On the outside of the tube a laminated sheet 
33 is laid, with its surface 34. 
A layer 35 of diamond granules and powder is applied by electrodeposition 
to said laminated sheet. 
These diamond granules carry out the function of thousands of single tools; 
they ensure high precision, strong abrasive power and long life. 
Abrasive action obviously depends on granule size. 
The fabric can be kept wet after passing through the humidifying bath and 
is kept constantly pulled. 
The roller 50 in FIG. 4 has a working surface coated with diamond powder 60 
divided up by smooth strips 42. 
In FIG. 5 the working surface 61 of the roller 51 is divided up by 
longitudinal grooves 71. 
The working surface 62 of the roller 52 in FIG. 6 is divided up by a series 
of smooth annular strips 72. 
The working surface 63 of the roller 53 in FIG. 7 is divided up by a smooth 
helical strip 73. 
In FIG. 8 the working surface of the roller 50 is divided up by a pair of 
smooth helical grooves 74 and 75 lying in opposite directions, one 
crossing the other. 
FIG. 9 shows roller 55 whose working surface 65 is divided up by a set of 
longitudinal 76 and annular 77 strips. In all the types described in FIGS. 
4-9, the smooth non-diamond coated strips can be replaced by grooves, or 
vice versa. 
The centre distance between strips or grooves can be constant or varied as 
preferred, on any one roller or on one roller and another. 
On any one roller there may be strips without diamond powder coating and 
grooves. 
The diamond coated surface may include areas with granules of different 
sizes and possessing different characteristics. 
The purpose of everything explained above is to produce particular effects 
on the appearance and colour of the fabric, as circumstances and 
preferences may require. 
Lapping stages may be one or more, each with four, six or eight lapping 
rollers. 
Movement of these rollers may also be transversal. The number of roller 
turns, their direction of rotation, clearance angle between fabric and 
lapping roller, tension of the fabric and speed of movement can all be 
regulated. 
The fabric can be treated on both sides simultaneously. 
All operating parameters are connected to a microprocessor so that they can 
be repeated as needed. 
Speed of regulation can be adjusted over a wide range, for example from 10 
to 30 m/min.