US2252123A - Method of producing moire patterns - Google Patents

Description

Aug. l2 1941i. H. GROSS METHOD OF PRODUCING MOIR PATTERNS Filed Sept. 16, 1939 ORNEY Patented ug. 12, 1941 UNITED rss Partnry OFFICE This invention relates to the production of moire scratch patterns on textile fabrics and, in particular, to the production of such patterns on fabrics made from cellulose acetate fibres, commercially known as celanese.

In the art of producing moire scratch patterns,` the fabric is customarily treated while in two layers, which are usually formed by folding the material either longitudinally or transversely to form a two-ply web `and passing the web through a scratching machine in which a moire pattern is scratched on the surface of the fabric. After passing through the scratching machine and after suitable conditioning, the web is passed between heated calender rolls which apply heat and pressure to cause the design to be reproduced upon the inner or abutting surfaces of both of the plies, the final result being a characteristic moire effect wherein the scratched pattern has a different lustre or sheen than the remainder of the fabric.

yIn carrying on this process, care must be taken to maintain the two layers in absolute registration as to weave. This is commonly accomplishedby the use of a tracing machine in which the two layers are inspected and cleaned, that is, adjusted to remove the traces and match the weave. This tracing and cleaning involves considerable care and expense and is particularly troublesome when treating fabrics which require moistening prior to scratching, such, for example, as cellulose acetate fibres. In treating such fibres, the material must be moistened, scratched and dried before being calendered. It is usually necessary to roll the material between each of these steps, due to the different lengths of time required therein. 'This rolling and re-rolling of the material renders the proper tracing and cleaning extremely diiiicult due to the natural creepage of the layers, particularly when formed into a large roll. It is accordingly an object of the present invention to provide a novel and improved process in which these diniculties are avoided.

Another object is to provide a novel and improved process for producing a moir scratch pattern on cellulose acetate fabrics.

Another object is to provide a process in which the tracing and cleaning operations are reduced to a minimum.

Another object is to provide a process in which the necessity for maintaining an exact registration between the weaves of the two plies in the scratching machine is eliminated.

Another object is to provide a process of the type above indicated which is adapted to treatment of large rolls of material.

Various other objects and advantages will be apparent as the nature of the invention is more fully disclosed.

Although the novel features which are believed to ce characeristic of this invention are pointed out more particularly in the claims appended hereto, the invention itself may be better understood by referring to the following description, taken in connection with the accompanying drawing, in which certain specific embodiments thereof have been set forth for purposes of illustration.

In the drawing,

Fig. l is a diagrammatic view representing certain steps of the present process and Fig. '2 is a diagrammatic View representing a modification of the moistening step.

Referring to the drawing more in detail, the material is indicated as received for treatment in the form of a roll l0 on which the material has been rolled in two layers, an upper layer Il and a lower layer I 2, to form a two-ply web.

The roll Ill may be formed in accordance with standard practice from dyedV goods which have Ibeen received for treatment. These goods are commonly received in the form of a single layer roll. The material may be transferred from this single layer roll to a standard folding machine which is adapted to so fold the material that both ends are made available. An end cloth may be sewed onto each of the ends of the material and the material is then passed in two layers through a tracer where it is inspected for matching of the weave. In the event that the weave of the two layers cannot be matched, the material is discarded as it will 'be unsuited for the subsequent process.

After passing through the tracer, the material is rolled into a double layer roll which constitutes the roll l0 of Fig. 1. In certain instances, two or more pieces of material may be attached together to produce a large roll and facilitate the further treatment.

The material from the roll I0 is now passed through a tank I4 containing a bath of water I5. The material may be held in this tank by suitable means, such as a roller I6. A suitable spray I1 may be positioned to wet the upper surface of the top layer Il so as to ensure an even and uniform wetting of the material as it passes through the tank.

terial.

A tank M lhas been shown merely for purposes of illustration. 'Ihe material may be wet in other ways, such as by a spray or by passing between wet belts or the like. Fig. 2 discloses an alternate method of wetting the material,

l which comprises a steam box 20 through which the material is passed from the roll I over a plurality of rolls 2l in a position to be contacted by steam which may be injected through a series of nozzles 22, fed by a supply pipe 23.

' It is to be understood, of course, that the mechanical construction of the steam box may be varied as desired and that the present showing is only intended to be diagrammatic. Y

In accordance with the present invention, the web, after being moistened as above described either by passage through the tank I4 of Fig. 1 or through the steam box of Fig. 2, is passed between guide rollers 25, after which the layers are separated, the upper layer Il passing over an embossed pattern roll 26 and the lower layer l2` being held by idler rolls28 out of contact with the pattern roll. A` scratch roll 29 having a plurality of flexible blades 3) of the usual form is rotated in a reverse' direction so as to scratch the moir pattern on the upper layer as it passes over the embossed pattern roll 26. The scratching machine is of standard construction and only so much thereof has been shown herein as is necessary lto an understanding of the present invention. After passing through the scratching machine, the layers I IV and I2 are again united by means of guide rolls 32 and may be passed over a guide roll 33 and rolled on a rod 34 to form a roll 35. The material on the roll 35 is in the form of a two-ply web, one layer of which has been scratched by the blades 30. It is also in a wet condition due to the moistening step above described. The roll 35 may now be stored for a length off time t0.V partially dry the same. They are preferably allowed to stand on end over night so as to remove aA suflicient amount of water to prevent the Ydye from running in the drying box, to be described. Y

After being thus partially dried, the material is taken from 'the rolls 35 andcis passed through a dryingbox of suitable construction in'which` the materialv is thoroughly dried. It is now passed through a tracer` in which it is` inspected and treated to remove traces and to clean the material, that is, to remove the linesV produced by lack of registration between the weaves of the two layers. The material may. be, re-rolled between the drying and tracing steps. if' desired. The materia-l thus traced and cleaned isnow passed between heatedl calender rolls, wherein heat and pressureY is applied to bring out the moir design upon the abutting surfaces of both layers of ma- It is of course important that the cleaning and tracing operation be accurately carried out s o that the moire design will be properly reproduced on both layers.

After passage through the calender rolls, the two layers may be separated and rolled into single layer rolls.,

In carrying onthe above process, it will be noted that only one layer is scratched to produce the moire pattern. Consequently, the necessity for exact registration between the two layers in the scratchingmachine is avoided. The preliminary'tracing is used-for the purpose of determining whether or not the weaves in the two materials are identical. Thereafter, the material may be rolled and rerolled a plurality of times and no attempt need be made to match the material during this part of the process. After the material has been scratched and dried, however, it may then be passed through the tracer and cleaned and matched before passing to the calender` rolls. By thus simplifying the process, it has been found that a more uniform moir pattern isobtained and that waste due to improper treatment and improper matching is materially reduced. By this process it is possible to treat large rolls of material, such, for example, as 700 to 800 double yards. As distinguished from this, the roll was limited by creepage of the material of the two layers to a maximum size of not over about double yards when the material was treated in accordance with prior processes which involved scratching of both layers.

While the invention has been shown particularly as applied to a` material of the cellulose acetate type,lwhich requires moistening ofthe fibres prior to scratching, it is to be understood that it may also be applied to the treatment of other fabric materials in which the moistening step may be omitted ifv desired. Certain specific terms have been used for convenience in referring to various details of` the invention. It is to be understood, however, that these terms are to be given as broad an interpretation as the art. will permit and that the invention is only to be limited in accordance with the following claims.

What is claimed is:

1. The method of producing moir scratch patterns in fabrics, whichcomprises folding said fabric transversely into a two-layer web, scratching a moire pattern on one of said layers only, matching the weave of said layers and applying heat and pressure to the two layers so as to cause the design :to be reproduced upon the surfaces of bothof said layers.

2. The method of producing moir scratch patterns in fabrics, which comprises folding said fabric transversely into a two-layer web, scratching a moire' pattern on one of said layers only, combining the layers to form a two-ply web, matching the weave in said web and passing the same between heated calender rolls to apply heat and pressure thereto for causing the design to be reproduced upon the surfaces of both layers.

3.' The method of producing moir scratch patternsin fabrics, .which comprises folding two layers of said fabric transversely to form a two-ply web, moistening said web, scratching a moir pattern on one of said layers only while moist, drying saidweb, matchingthe weave in said two layers,and'sub'jecting-said web t0 heat and pressure to cause the design to be reproduced. upon the surfaces of, both Aof-said layers.

4; The method of producing moir scratch patterns in fabrics made from cellulose acetate bres which, comprises folding said fabric transversely to form a two layer web, moistening said web, scra.tching a moire pattern on one of said layers only while moist, drying said web, matching the weave thereof and subjecting the web to heat and pressure for causing thepattern to be reproduced von the surfaces of both of lsaid layers.

HERMAN GROSS.

Images