US3846970A

US3846970A - High bulk and potentially high bulk fibrous material

Info

Publication number: US3846970A
Application number: US00500599A
Authority: US
Inventors: K Hitomi; K Takagi; S Nomura; S Okada
Original assignee: Daido Keori KK; Mitsubishi Rayon Co Ltd
Current assignee: Daido Keori KK; Mitsubishi Rayon Co Ltd
Priority date: 1961-10-03
Filing date: 1965-10-22
Publication date: 1974-11-12
Anticipated expiration: 1991-11-12

Abstract

Continuous filaments are subjected to treatments to produce in the axial direction of each filament alternating and repeating high shrinkage segments and low shrinkage segments. Yarns and fabrics produced from the filaments will bulk out in the low shrinkage segments by the shrinkage of the high shrinkage segments upon being subjected to a relaxation treatment.

Description

United States Patent [191 Hitomi et al.

[451 Nov. 12, 1974 HIGH BULK AND POTENTIALLY HIGH BULK FIBROUS MATERIAL Related U.S. Application Data [62] Division of Ser. No. 142,546, Oct. 3, 1961, Pat. No.

[52] U.S. Cl. 57/140 R, 28/7217, 57/140 BY, 57/157 MS, 161/172 [51] Int. Cl ..z D02g 3/24 [58] Field of Search 28/72, 72 F, 72 G, 72 K,

28/595, 71.3; 57/157, 157 MS, 140, 1401, 34 H; 161/172, 177;264/168, 167, 210, 290;

[56] References Cited UNlTED STATES PATENTS 2,820,986 l/1958 Seney 57/1401 3/1959 Lohr et al. 57/140 2.953.427 9/1960 Eg'ger 57/1401 2,975,474 3/1961 Smith 57/140 1 2,980,492 4/1961 Jamieson et al. 264/210 3,018,516 3/1963 Evans 28/72 F 3,107,972 10/1963 Pitzl 57/140 1 3,116,197 12/1963 Kasey, Jr 57/1401 3,127,915 4/1964 Bottomley 57/140 1 3,302,385 2/1967 Ruddell et al. 57/157 Primary Examiner-John Petrakes Attorney, Agent, or Firm-Robert E. Burns; Emmanuel J. Lobato; Bruce L. Adams [57] ABSTRACT Continuous filaments are subjected to treatments to produce in the axial direction of each filament alternating and repeating high shrinkage segments and low shrinkage segments. Yarns and fabrics produced from the filaments will bulk out in the low shrinkage segments by the shrinkage of the high shrinkage segments upon being subjected to a relaxation treatment.

18 Claims, 37 Drawing Figures PATENTEUNUV 12 1914 11846; 970

sum 1 12 FIG. I

i I 2 t? 6% FIG. 20. H F|B.2b H L PATENTEU HOV 12 E374 SHEET 0% OF 12 Pmmmmw 12 1914 31346; 970

sum as or 12 FIG. I?

Pmmmm 12 m4 SHEET 0s 0F 12 FIG. l8

PATENTEDNHV 12 1914 SHEET 07 HF 12 FIG. 24

PATENIEU NOV 12 m4 SHEET 08 0F 12 FIG. 25

PMENTEDnnnznsm 3L846l970 sum 100F12 PATENIEDHBY 12 m4 3846370

sum

11 or 12 HIGH BULK AND POTENTIALLY HIGH BULK FIBROUS MATERIAL This is a divisional application of our application, Serial No. 142,546, filed Oct. 3, 1961, now US. Pat. No. 3,248,771.

The present invention relates to new and improved high bulk and potentially high bulk fibrous materials, and more particularly to new and improved high bulk and potentially high bulk synthetic fibrous materials, especially textile products.

Bulky textile fibers are known. These fibers are frequently prepared by applying processings such as heat treatment, twisting and untwisting or like treatments to fibers in the form of yarns. Fibers for use in high bulk textile products are also frequently prepared by means of mechanical crimping. Also, fibers for use in high bulk textile products are found in the form of fibers looped in a random manner by applying jets of compressed air thereupon. Fibers for use in high bulk textile products are prepared and made generally available by many other means. a

The high bulk textile products which are known and serve to clarify the principles of the present invention are known as high bulk yarns obtained by applying heat treatment to the spinning material which consists of mixtures of shrinkage and non-shrinkage fibers after said material has been spun, whereby the shrinkage fibers are shrunk and thus the non-shrinkage fibers project out.

The main object of the invention is toprovide novel and improved fibrous material having superior properties to give high bulk textile products which are novel and improved in high bulkiness and mechanical properties.

Another object of this invention is to provide fibrous materials which are characterized in the sense of being usable for high bulk textile products having wellbalanced properties, and excellent appearance and feel to the touch and the like.

Still another object of the invention is to provide fibrous material for use in high bulk textile products. The fibrous material is not limited in kind and type and is able to be given sufficient bulkiness in any condition and at any stage of processing, for instance, prior to and following the yarn spinning process and in the form of knitted, woven and non-woven fabrics.

- In order to fulfill the above-mentioned objects, fibrous material according to the invention consists of single filaments, each having in the direction of the fiber axis alternately a high shrinkage portions which shrinks to a greater extent upon being subject to subsequent treatments such as by heating and a low shrinkage portion which shrinks to a lesser extent under the same conditions.

Further, according to the invention, high bulk textile products such as novel and improved threads, knitted, woven or non-woven fabrics, industrial use textile products and the like are produced from the fibrous material of the invention.

Underwear, outerwear, fancy works, ornamental goods, carpets and other finished textile products having high bulkiness can be produced from the abovementioned textile products. Other objects according to the invention will be apparent from the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a diagrammatic representation of a general example of the fibrous material for use in high bulk textile products (which may be very often referred to only as the fibrous material" hereinafter),

FIGS. 2a and 2b are diagrams to represent a basic property of the fibrous material according to the invention, in which FIG. '2a shows many of the fibers arranged in parallel and given preliminary treatments and single filaments of the fibrous material the same as are shown in FIG. 1, while FIG. 2b illustrates the fibrous material shown in FIG. 20 being given secondary treatments by heating.

FIGS. 3a and 3b represent a single filament of the fi brous material of FIGS. 2a and 2b on an enlarged scale.

FIGS. 4a and 4b represent diagrams to describe the processing theory for conventional fibers; FIG. 4a shows a parallel arrangement of high shrinkage fibers and non-shrinkage fibers mixed, while FIG. 4b represents the fibers of FIG. 4a after being given a heattreatment.

FIGS. 5a and 5b are enlargements of a pair of the strands shown in FIGS. 4a and 4b, respectively.

FIG. 6 is a diagrammatic viewof yarns prepared by using the fibrous material according to the invention.

FIG. 7 is a diagrammatic view of conventional bulky yarns.

FIGS. 8a and 8b represent diagrammatically the simplest apparatus for the production of the fibrous material according to the invention as well as an example of the invention wherein said apparatus is used; FIG. 811 represents a condition prior to the preliminary treatments, and FIG. 8b, a condition after the said treatments.

FIG. 9 represents a vertical sectional view of a sectional zone of the said apparatus.

FIG. 10 represents a perspective view of the gripping unit, viewed separately.

FIG. 11 shows diagrammatically the structure of one type of fibrous material according to the invention;

FIG. 12 is a similar view of another embodiment of the fibrous material of the invention;

FIG. 13 is a similar view of yet a further embodiment of the fibrous material of the invention;

FIG. 14 is a similar view of a still further embodiment of the material of the invention;

FIG. 15 is a diagram for illustrating diagrammaticall the mode of processing filament yarns.

FIG. 16 is a side view, partly broken away, of an example of a continuous production process according to the invention which is suitable to produce the fibrous material according to the invention. a

FIG. 17 is a section along the A-A line of FIG. 16.

FIG. 18 is a diagrammatic enlarged partial side view to represent the overfeeding mechanism and its principles. I

FIG. 19 is an enlarged perspective view, partly broken away, to represent a gripping piece fixed on a chain link.

FIG. 20 is an enlarged section along the 8-8 line of FIG. 19.

FIG. 21 is an enlarged section along the CC line of FIG. 20.

FIG. 22 is an enlarged perspective view of a spring case.

FIG. 23 is an enlarged perspective view of a chain link.

FIG. 24 is an enlarged perspective view representing another example of a gripping piece fixed on a chain link.

FIGS. 25-29 represent another useful continuous production apparatus according to the invention; FIG. 25 is a side view of said apparatus, partly broken away; FIG. 26 is a section view along the DD line of FIG. 25; FIG. 27 is an enlarged section along the E-E line of FIG. 25; FIG. 28 is an enlarged partial side view representing diagrammatically the overfeeding mechanism.

FIG. 29 is an enlarged perspective view, partly broken away, representing a gripped piece on a chain link.

FIG. 30 is an enlarged side view, partly broken away, of further useful continuous production apparatus.

FIG. 31 is a section along the EE line of FIG. 30, and,

FIG. 32 is a plot of tenacity and elongation curves.

The meaning of terminology as used through the present specification and appended claims is given below: The term single filament or elongated fibrous unit is used to represent one of the minimum units of a fiber. No matter what designation may be used, single filament or elongated fibrous unit has substantially the above meaning. Silver, top, tow, filament or the like is used throughout this description to mean a common thing, regardless of the condition, shape or properties of any given fiber.

H and L are relative to each other; by the letter H is meant the nature and portion of high shrinkage due to treatments such as heating or the like; by the letter L is meant the nature and portion showing none or little shrinkage due to treatments such as heating or the like. A nature showing more than approximately percent difference in shrinkage against H is included in L.

By the letter L is meant the portion which should subsequently be designated as L.

By preliminary treatments is meant an operation to provide fibers which in the direction of its axis have alternate H and L portions of the prescribed length by completing partial relaxation (under tension or nontension) or stretching of the said fibers by means of treatments such as heating, and by "secondary treatments is meant an operation whereby after the fibers having alternate H and L portions are spun into yarns, or then woven or knitted or made into non-woven fabrics, and the L-portion is projected out in relation to the shrinkage of H-portion due to treatments such as heating.

-As heating medium for the said fibers, either a dry heat or a wet heat can be used. Heat treatment can be replaced by solvent treatment either in the gas phase or the liquid phase (or the liquid phase), dielectric heating or a radiation treatment.

The invention is applicable to man-made fibers which are or will be known. Particularly preferable fibers in this respect are those which possess a nature that such strain imparts by stretching is fixed under normal conditions. The strain due to stretching is relaxable with accompaniment of shrinkage, upon subsequently being treated such as by heating or the like.

For this purpose, polyacrylic fibers are highly recommended. Similarly, polyvinyl alcohol-, polyester-,

pololefin-, diacetate-cellulose-, and triacetate cellulose fibers are preferable.

The special features of the novel fibrous material according to the invention will be apparent in comparison with known bulky yarns from the following description I taken in connection with the accompanying drawings. In the following description, the fibrous materials according to the invention are those treated by heating.

The fibrous material according to the invention is shown in FIG. 1.

For a better understanding, conventional bulky yarns are described first.

CONVENTIONAL BULKY YARNS First, reference is made to FIGS. 4a, 5a, and 7 of the accompanying drawings.- High shrinkage fibers as denoted H which shrink by heating at temperatures higher than 5060C and low shrinkage fibers donated L are employed as materials, which are mixed normally, for instance, at a ratio of 40:60, The mixture is called conventional fibrous material", as against the fibrous material according to the invention.

When the known fibrous materials are spun into yarns and subsequently heated, the yarns become high bulk yarns as shown diagrammatically in FIG. 7 due to the L fibers bulking out because of the shrinkage of H fibers subjected to the resistance of fiber bundles or due to twisting as shown in FIGS. 4a and 5b. In this case, the parts as denoted by arrows in FIGS. 5a seem to remain substantially unshifted under the resistance caused by twisting and the like.

High bulk yarns using the fibrous material according to the invention Reference is made to FIGS. 1, 2a, 3a and 6. The fibrous material according to the invention comprise a plurality of single filaments. Each of the single filaments has, in the direction of the fiber axis, alternately a high shrinkage portion H, which shrinks to the greater extent by heat treatment at temperatures higher than 5060C and a low shrinkage portion L.

The length of the portion H may be selected at will, whie that of the portion L can be determined by predetermining the ratio L/H at a proper value.

The process for producing the above-mentioned fibrous material will be fully described. Now, the starting material comprises only such fibers which may shrink mainly by heating. This material or fibers is gripped by suitable mechanical means at a number of axially spaced portions therealong, and subjected to heat treatment before spinning with said gripped portions being thus isolated from the influence of the heating medium. The exposed, axially spaced portions L of the fibers are subjected thereby to the heat treatment, while on the contrary, the gripped portions H are effectively insulated from heating. In practice, the length H and the ratio H:L can be selected at will. In the example, shown in FIG. 3a, the relation H:L is selected to be 10:12 mm. FIG. 1 has been also plotted under these numerical assumptions.

When the fibrous material has been spun into yarns and then subjected to a second heat treatment, the L portions accompanied by the shrinkage of the H portions are bulked as shown diagrammatically in FIGS. 2b and 3b, and consequently, high bulk yarn is produced. Those skilled in the art understand that in a spun yarn the threads, or filaments are restricted longitudinally at axially spaced points of the yarn and not as shown diagrammatically in FIG. 2b. In FIG. 6, yarn made of fibrous material according to the invention is generally designated 1. In FIG. 7, conventional bulky yarn is gen-- erally'designated 2. In these Figures, single filaments are denote by 1, l" and 2, 2", respectively. The novel yarn 1 comprises two single filaments, each comprising a number of alternately arranged portions H and L. For clarity, portions H are illustrated in chain lines, while portions L are shown in full lines. In addition, one filament 1' is shown with a thick line and the other filament 1" is illustrated with a thin line.

It will be noted from FIG. 7, one filament 2' of the conventional bulky yarn 2 consists wholly of the H type fiber and the other filament 2" comprises a L type fiber. More specifically, the conventional bulky yarn comprises two types of completely different fibers H and L, while the novel fibrous material of, the invention comprises a plurality of filaments, each of which comprises an alternate arrangement of different portions H and L, extending in the axial direction of the fiber, thus providing a substantial difference between the two and thereby giving possibilities of producing remarkable differences in the nature and quality of the final products prepared therefrom. The realizable difference in appearance, tenacity and elongation, elastic recovery, uniformity in bulkiness and other physical properties of the final products, such as threads produced from the novel and the conventional fibrous material are as follows: I. Tenacity and elongation In connection with the tenacity, which will be easily recognized from the uniformity in bulkiness, the novel filaments l greater tenacity and less bulked-out projections as produced after bulkying treatment than in the case of the conventional filaments 2, as illustrated in FIG. 4b. Thus, with the novel filaments, almost all of the constituent fibers take part in providing the tenacity of the produced bulky yarn, so that the strength thereof may be amazingly increased.

The following table, which shows relative experiments on knitting yarns as produced both in the novel and conventional ways and demonstrates the degree of tenacity decrease as produced in the bolk-treated yarns in comparison with those before such treatment.

filaments the above-mentioned straight arrangement of core fibers does not exist in any way and generally forms a spiral shape thereby elongation in the initial elongating stage becomes considerably large, as will be illustrated in detail in connection with tenacity curves plotted against eloagation.

II. Degree of Elastic Recovery From reasons as was set forth in item I, the conventional filaments 2 provide their elastic recovery solely relying upon the H-fiber components, preferably premixed about percent of the total, while the L- cornponents are floating during the initial loading conditions of the yarn. On the contrary, with the novel fila ments 1, elastic recovery is provided by the action of all the contained fibers, even when initially loaded. Thus, the recovery will be amazingly improved after loading and without any substantial influence upon the Youngs modulus of the yarn produced therefrom.

The abovementioned tenacity-elongation curves are shown in FIG. 32. Under initial loading only, H- components fibers preliminarily mixed therein take charge of resisting the load, while L-components become floating during the same period. The aforementioned tendency of the conventional filaments 2, may be clearly acknowledged by the substantial displacement of yield point of the conventional yarn.

Further, under higher loaded conditions, the conventional filaments 2 are liable to be subject to a remarkable relative shift or slippage of H-fibers, or even breakage thereof, and then to deformation in the fibers in the sheath part, thus showing practically a permanent deformation of the yarn. On the contrary, with the novel filaments l, a satisfactory elastic recovery may be provided after higher loaded conditions.

III. Uniformity in Bulkiness As is commonly known, the degree of uniformity in bulkiness of yarn not only has a large influence upon the appearance, touch and the like esthetic performances, but also has an intimate relationship with the mechanical properties of the final products produced from the yarns. This factor plays a great role in the finishing procedure of knitted, woven fabrics and threads or the like made from the yarns.

More specifically, the conventional bulky yarns as denoted by (2) have a deficiency in that they are flat- TABLE Tenacity. grs. Elong'at ion, Degree of Yarn Count Contracefore tion of Before After Reduc- Before After Test No. Kind of Yarn Bulking Yam 7: Bulking Bulking tion% Bulking Bulking l novel yearn (l) 2/33 26 765 719 6 I2 47 2 ditto 2/36 26 69l 675 2 ll 44 3 ditto 2/38 25 63] 620 2 l I 43 4 ditto (*1) 2/36 26 627 604 4 ll 44 5 comparable 2/36 28 647 412 36 I2 conventional yarn (*2) 6 ditto (*3) 2/36 27 635 386 39 12 4 Remarks:

I Yarn count is same as in case 2. but the preliminary twist has been selected to be 10% less than in the latter case.

2 H:L 40 turbo top was used. '3 HzL 40 z 60; cut fiber top was used.

Th s n i erati n m y be appl to h case tened, in case they are dyed as yarn under heat and tenof elongations. With the conventional filaments 2, the core fibers comprising mostly H fibers are in a state of substantially straight arrangement, while with the novel sion. This drawback is attributable mostly to the change in state of the aforementioned floating fibers. Effective remedies for solving this drawback have not w yet been found and the problem is now getting serious in various fields of textile manufacturing. These difficulties can be solved by the invention by the novel fibrous material having a proper length of H, a suitable ratio of H L and a favorable shrinkage of each single filament or fiber are employed. Consequently, efficient uniformity in the bulkiness and a substantially equal appearance to that of knitting yarn by 100 percent wool products can be obtained.

Fibrous material which were properly chosen as was seen above does not shown any flattening tendency when the above-mentioned finishing procedure in carried out.

IV. As to the conventional bulky yarns, it has been reported many times from the view point that the ratio H L should be employed in consideration of the expected properties of the yarn, the shrinkage caused by uneven mixture, the uniformity of bulkiness, the degradation of yarn tenacity, the bulkiness and the like. Every report recommends a mixing ratio of ca. 40:60 to be most efficient, and has tendency to deny to change this ratio greatly. However, according to the invention, the problem involved in the above view point is being solved. Namely, the above solution is brought by changing in the shrinkage degree of H-fibers, the length of H, the ratio of H L, as well as a combination of these factors. With respect to the novel fibrous material as obtained by the invention, satisfactory products can be obtained from being affected greatly upon properties, appearance, and touch by Hfibers properties and separation between higher shrinkage portion H and lower shrinkage portion L.

Thus, according to the invention, there are the shrinkage ratio of fiber itself described in IV, and the combination of the length of H and the ratio of H L. Furthermore, there are various kinds of combinations based on the invention. These combinations may be applied to various cases which will be described in the next paragraph, in order to obtain particular characteristics and merits.

V. Another type of novel fibers shall be illustrated with reference to the several accompanying drawings:

In FIG. 11, the fibrous material representing various ratios of H L is schematically shown. In the Figure, H shows a high shrinkage portion having a length of 15 mm. L represents a low or non-shrinkage portion, 16 mm in length. In the similar way, high shrinkage portions H and H extend l5 and 25mm, respectively. Low shrinkage portions L and L are 41 mm in length, respectively, as is shown. The single filament comprises a number of units, each having the above mentioned six elements H L,, H L H and L Now, considering in this case, between two of the fibrous materials having the relation H L of (mm) and I0 (mm), respectively, the apparent bulkiness of the latter will be larger than that of the former, when such kind fibrous material are shaped into yarns, fabrics and the like.

As a further example, two fibrous materials having the relation H: L of 10; 15 (mm) and 20 (mm) are considered. In this case, the latter will represent a lower Youngs modulus than in the case of the former so that it may become more soft when such kind fibrous material are shaped into yarns, fabrics and the like.

Thus, various properties may be possessed by the final products, depending upon the length H, as well as upon the ration H 1 L. It will thus be clear that the relation of lengths H and L should be selected depending upon the desired final use of the novel fibers.

As an aspect of the invention, therefore, the single filament comprises cyclically arranged units, each of which includes two or more different lengths of H and ratios of H L. By this means, yarns knitted or woven products produced from these novel single filaments may represent highly complicated compositions.

In connection with the fibrous material having compositions as set forth in the above, hand effects similar to those obtainable by the conventional mix-spinning of variable denier fibers or variable length fibers which is commonly employed in the conventional spinning process are recognized, thereby providing highly complicated mixing and configurating effects. Moreover, according to the invention, the conventional mix-spinning stage can be omitted and the mixing effects which assures the uniformity of the final products can be remarkably improved.

VI. In FIG. 12, two kinds of a single filament mixed are schematically shown, which have different lengths of H and different ratios of H L each other. It is also possible to mix three or more such different filaments together.

By the above-mentioned measures, not only variations in length H and ratios H L, but also another factors such as variable denier, variable fiber length and the like may be further incorporated in the bulky yarn products. For example, the deniers of the filaments are 3 and 5, respectively. The relation of H L are 20 30 (mm) and 15 20 (mm), respectively. In addition to such modified filaments, when the fibrous material of different H and L described in V having complicated and mixed effects are used, high bulk textile products V with more peculiar hand and other properties may be provided.

VII. In FIG. 13 are shown the fibrous material that only H-portion are situated in the extreme ends of a single filament.

When this type of filaments are employed, spun and subjected to the secondary treatment, these provide the yarn which is less fuzzy by drawing the extreme ends of filaments in the yarn.

VIII. A single filament illustrated schematically in FIG. 14 has L-portions at its extreme ends. When this type of filaments are spun and subjected to the secondary treatment, these provide the yarn which is more fuzzy.

The above described feature that the opposite ends of a novel filament are shaped solely in the form of H- or L- portion, is preferably combined with any of the novel features as set forth hereinbefore in items V-Vl. As a result, the fibrous material with deformed shape and characteristics are obtained.

It will be clear that all the specific features as already mentioned above can be combined efficiently with any one of those which will be explained hereafter. As a result, this gives various possibilities to provide still improved properties and hands to the bulk textile products prepared from the novel fibrous material according to the invention.

IX. Filaments According to conventional techniques there are various ways in obtaining textures yarns from filaments, of which two general classes are known, namely, high expansibility and shrinkage, and high bulkiness. As regards the latter process, there are loop formation of tibers by means of compressed air streams as is seen in Taslans case and mixed twisting between high and low shrinkage yarns.

Next, the application to filaments of the invention shall be described in details with reference to FIG. hereinunder:

As is shown in the figure, the filaments are temporarily untwisted and arranged preferably in parallel or unchanged state. Under these conditions, they are subjected to the primary treatment to represent I-I-portions and L-portions alternately in the oblique direction and then subjected to the secondary treatment for obtaining high bulkiness. In the above processing, secondary treatment after two or more fibers are plied together, is more effective. Instead of forming each kind of portion in a laterally oblique direction, it may be made a right angle with the fiber direction, if desired.

After the above primary treatment, the filaments may be treated by means of compressed air jet streams to subject the fibers to random looping thereof, as well as to shifting and random arrangement of neighboring similar portion, i.e. random arrangement of H and L portions. Then, the filaments are subjected to the secondary treatment for the purpose of bulking after one plied yarn or more are manufactured. As a result, various outstanding features may be added compared with bulkiness by the ordinary loop formation.

X. Still another type of fibrous material according to the invention may consist of blend with shrinkage and non-shrinkage natural and artificial fibers, when a single fibrous material or more is blended.

If high and low shrinkage fibers are blended with wool according to the conventional bulky yarn preparing process, the low shrinkage fibers L are normally positioned within the sheath portion, the wool fibers within the intermediate portion and the high shrinkage fibers H within the core.

With use of the aforementioned novel fibrous material, however, the similar processing will normally result in that the wool fibers occupy the relatively outer layers, so that the desirous and advantageous quality of material having an excellent feel when touched may be highly improved, for instance, in the case of mixed fiber spinning with wool fibers.

XI. Knitted and woven fabrics According to the invention using the abovementioned fibrous material, high bulk knitted and woven fabrics may be provided in addition to the yarns as mentioned above. These final products represent high tenacity, high initial elongation value, low plastic deformation, high elasticity and successful spongy characteristics favorable to hand touching thereof. The constituent fibrous materials are less fuzzy, so that the surface of the fabrics produced therefrom is smooth and clear, thereby possessing especially high resistance to raising and pilling. These products represent not only least unevenness in the bulkiness, but also substantially no change in-their color shade before and after bulking in the case of yarn dyed fabrics.

For carrying the invention into effect, there are gen erally two ways of processing. In the first place, the novel fibrous material is prepared by subjecting it to the primary treatment under consideration of the desired nature and characteristics to be possessed by the intended final products, such as design fabrics, heavier or lighter fabrics, and the like which are spun into yarns orthreads and then worked into knitted or woven products, which are then subjected to the secondary treatment. In the second place, the fibrous material after being treated primarily, is successively subjected to the secondary treatment in the form of yarn, and then worked into knitted or woven products. The thus produced final products through either processing may successively provide the aforementioned additional characteristics to those obtainable by the conventional bulky yarn preparing process. More specially, the latter process are especially characterized by the higher te-v nacity, least fuzzing tendency and the like of the yarn, which mean high superiority and large convenience in the knitting or weaving process.

XII. Non-woven fabrics According to the invention, non-woven bulky fabrics can also be produced. All of the aforementioned novel fibrous material may be advantageously employed for production of nonwoven fabrics.

Non-woven bulk fabrics prepared from the novel material are characterized by their uniformity, since the webs may be successfully mixed together even by a single process, which uniformity is especially shown by the thickness and mechanical strength of the thus produced non-woven fabrics. The above mentioned advantage obtained by the invention, that is, the dispensability of the mixing stage will contribute to a substantial reduction of the production costs.

To accomplish various purposes as have been described above, apparatuses by the invention are schematically shown in the several Figures of the accompanying drawings The term Example as set forth hereinafter will be directed substantially to the process and the stages thereof.

Example 1 This example shall be explained in connection with the production of novel filaments, H-portion and L- portion of which extend 10 mm and 12 mm long, respectively.

FIGS. 8a and 8b, 9-10 illustrate schematically a highly simplified device for producing above mentioned type of fibrous material according to the invention.

The device comprises a number of grippers, each consisting of a couple of cooperating gripper pieces 6. Each gripper piece 6 is made preferably of iron 3 and has an elongated form, the width of which is selected to be 10 mm, that is, equal to the length of each portion H. Each piece 6 is lined on its inside surface with an elastic strip 4, preferably made of rubber, plastics or the like. Each set of piece 6 is detachably united together by means of set bolts 7, passing through clearance holes 5, which have been drilled through the piece and liners, with the latter abutting against each other as shown in FIG. 9. The gripper is tightened on bolts 7 by nuts 8.

As the starting material to be processed, top turbo stapler of acrilonitrile fibers are employed. The above fibers have been heat stretched at a temperature of C with a stretching ratio 1.31 and have 2.5 deniers, degree of contraction of 18 percent and mean fiber length 5 in. These fibers are gripped by a plurality of gripper and are tightened by bolts and nuts 7-8. The

distance L, 12 mm in the present example, must be determined by adjusting the free space between two adjacent gripper and in consideration of the above mentioned degree of shrinkage, 18 percent, the distance between two adjacent gripper is selected to be 14.6 mm, as illustrated in FIG. 8a. The squeezing sets are then slidingly shifted in the longitudinal direction of the fibers and on and along guide rails 9, so as to loosen the free portions of fibers, as clearly illustrated at L in FIG. 8b. The gripper sets, thus shifted slightly towards each other, are fixedly positioned by tightening bolts 10, which are screwed through rails 9 laterally. The fibers are then, under these conditions, immersed into a treating bath, not shown, containing a body of boiling water for about 2-3 seconds, resulting in the slackened portions of the fibers subjected to contraction and practically tensioned, as schematically represented by dash-dotted lines L in FIG. 8b. The thus treated fibers are taken out from the bath, cooled and dried in the open air, and finally released from the grippers. The squeezed portions of the fibers, having been insulated from the influence of the heating medium, are now kept unchanged, thus providing the high shrinkage portions H, while the practically heat treating portions L extending between each two adjacent grippers are transformed into low or nonshrinkage portions L. In this way, the novel fibrous material having a H:L relation of 10:12 (mm) and illustrated in FIG. 1, has been prepared. In FIGS. 8a and 8b, the dimensions of H, L and L are shown as 10, 14.6 and 12 mm. respectively.

In the above case, the distance between the grippers shifted towards each other must be shorter than 12 mm, and may be adjusted to any suitable length, if the present condition is satisfied. If the above distance should be set to a value longer than 12 mm in this example, the fibers would be heat set, which is, however, excluded from carrying out the present stage of the invention. Under some conditions, however, such heat setting may be advantageously utilized for a specific purpose, which will be described in more detail hereinafter.

The primarily treated fibrous material is then spun into yarn as in the conventional manner, and then subjected to the secondary treatment by dipping it into a boiling water hath, not shown, for about one or two minutes. Upon this treating, the portions H are subject to shrinkage and the alternate portions L are correspondingly bulked out, as already described in connection with FIG. 6.

As the heating medium for the primary and secondary treatments, hot air may also be employed, if desired. The treating temperature for the first treatment is preferably adjusted to 140-150C, and thst for the second treatment advantageously to the same temperature range, in either case of wet or dry processing.

Instead of heat treatment, any conventional different process, such as chemical treatment may be employed for either or both of the above mentioned two stage treatments.

The substantial disclosures as set forth in the present example may be equally applicable to several further examples to be given hereinafter, except otherwise noted.

For the mass production of the above mentioned novel fibrous material, such a machine may be preferably used, wherein a number of grippers are continuously kept in motion in a successive order, and the material to be treated is gripped by the grippers at separate portions therealong and the free portions thereof are kept slackened by overfeeding provided by the movable grippers in succession.

Such a machine is described in detail, wherein single filament are treated by the machine so as to form a number of alternately arranged high and low shrinkage portions in and along the filament, adapted to be advantageously used for the production of high bulk textile products. The machine may be referred to as the first embodiment of machine hereinafter 'for convenience only.

Now, especially referring to FIG. 18, the present machine shall be described below substantially at its principle only.

The circulating systems are herein shown in the form of endless carrier bands such as endless chains, which are so arranged that they travel continuously along in the same direction, as long as they meet together. In the Figure, both these systems are shown in part only, where they commence to meet together and to where the material fiber bundles are supplied. Each of the endless chains carries thereon a number of separate gripper elements 28, which are urged resiliently to expand in the outward direction as shown, when they are in their off-service position. In this figure, the right hand couple of gripper elements are shown, when they are about to contact together, while the left hand two couples are illustrated in their cooperating or gripping conditions, thus constituting two united grippers 66. When circulating in their free state, the elements 28 have each a radius, if measured from the center of a carrying wheel, say 14, to the working surface of the element, corresponding to a sum of working radius r plus and a contractive distance r. As the chain travels, each couple of gripper elements are brought into contact with each other at a crossing point P of two circles having the radius r t r about the chain wheel centers 0. If more exactly considered, the said radius extending from the wheel center of the contact point of each gripper element must be expressed by r r r", corresponding to the distance between the wheel center and the leading upper edge of each element, wherein, however, r is nearly equal to r. For this reason, the radius under consideration shall be expressed conveniently by r t r. As both chains continue to travel along, after commencement of gripping the fiber bundles by the couple of cooperating gripper elements 28, and these members arrive at a further advanced point P, which is really the crossing point of the advancing bundles with the center-to-center line OO, the grippers are brought into exact registry with each other, after being somewhat compressed or retracted, thus they constitute together a complete gripper 66 and the fiber bundles are caught positively there between at this point. The distance between two points P and P can be determined as a function of the contracted radius r and the retractable distance r.

According to a practical experiment, 1 in., chains were employed and r and r' were selected to be 77 mm and 6 mm, respectively. In this case, the distance P-P' was practically 32 mm. When the width of each gripper element is taken as 15 mm, the free distance from the preceding gripped portion of the bundles to the newly gripped portion extends 24.5 mm, or 32 mm 15/2 mm. After the complete engagement of the two coop- 10.4 mm, or 25.4 mm 15 mm. Thus, the overfed ratio of the fiber bundles is nearly equal to 2.3 times wherein 2.3 is a ratio of 24.5/10.4.

In this way, the fed thermo-shrinkable bundles are successively gripped by a number of resiliently biased grippers while being overfed at a proper ratio, a slackened portion L is formed between each two successive gripper units. By subjecting these bundles to heat treatments, while being kept gripped and slackened conditions and carried forward by the traveling chains, the slackened zones L are transformed into the low shrinkage portions L, while the gripped portions are kept unchanged in their character, thereby forming the high shrinkage portions H. Thus, the fibrous material is provided therein alternately with H- and Lportions, when seen in its longitudinal direction.

More specifically, referring to FIGS. 16-17, the construction and operation of the above machine shall be described below in more detail.

In the forward part of the machine, to the right hand in FIG. 16, two parallel shafts 11-12 are vertically separated from each other and rotatably mounted in machine framef. Two

chain wheels

13, 13 or 14, 14 are fixed mounted on either

shaft

11 or 12, respectively. Similarly, another two shafts 1516 are arranged and rotatably mounted in the rearward part of the machine and in a symmetrical arrangement to the forward shafts 11-12. These two rearward shafts 15-16 carry thereon two chain or sprocket wheels l7, l7 and 18, 18, respectively. Substantially above the

upper shaft couple

11 and 15, other shafts 20 and .22 are rotatably mounted and mount in turn thereon two

chain wheels

19, 19 and 21, 21, respectively. In the similar way, there are rotatably mounted two

lever shafts

24 and 26 substantially below the

shafts

12 and 16, and two chain sprockets or

wheels

13, 13 and 15, 15' are fixed on the

lower shafts

24 and 26, respectively.

An upper set of the

wheels

13, 17, 21 and 19 supports an endless roller chain 27a and another upper set of the

wheels

13', 17, 21, and 19 carries a similar chain 27a. for cooperation with each other, so as to establish the upper circulating system. In the similar way, the lower circulating system comprises two endless chains 27! and 27!, which are carried by a first set of

wheels

14, 18, and 23, and a second set of

wheels

14', 18, 25 and 23, respectively. Each of said circulating system carries elastically thereon a number of gripper ele ments 23, which have been described hereinbefore in connection with FIG. 18.

As clearly noted from FIGS. l922, the chain comprises a number of links 29, each of which is attached with an attachment 30 at each side thereof, as most clearly illustrated in FIG. 20. Attachment 30 is formed with two separate pins 31 for mounting respective spring 37 contained within a casing 34, which comprises two small box elements 32 connected by two connecting bars 33, as clearly seen in FIG. 22. At the central portion of casing 34 and between the two box elements, a groove-like opening 35 is formed. Spring casing 34 is assembled with a chain link 29 such that the attachments 30 are positioned within the casing and the link is kept in slidable engagement with groovelike opening 35. Two springs 37 are contained as above mentioned within each box element 32. The springs are supported at their one ends by the projecting pins 31, while the opposite ends of the springs are held in position by positioning pins 31 extending downwardly from the bottom surface of a holder 36, to which the connecting bars 33 are fixed, for example, by fixing bolts 41 or otherwise. Thus, if will be clear, that each holder 36 extends fixedly between the two corresponding links 29 comprised in the both side upper circulating chains 27a and 2714'. As will be noted, the lower chains 27!, 271, are constructed similarly in this respect. On the holder 36, an elongated gripper element 28 made of an elastic material such as rubber, synthetic resin, leather or the like, is fixed as by dovetail connection 38 or the like. Gripper element 28 has a width cor responding to the length of one of the H portions to be formed in fibrous material, as well as a proper thickness for positive, yet resilient grip of the material. The length of gripper element 28 is so selected that a larger as possible number of gripper elements are mounted on both of the upper and lower circulating chains at regular intervals and in the opposite, yet resiliently cooperating arrangement between the two systems. Thus, as the upper and lower endless chains continuously circu late along their closed passages, each couple of cooperative gripper elements are urged in their outward direction, brought into contact and correct registry with each other, retarded to a some degree, kept in pressure registry, removed from each other, urged outwardly, and so on, thus repeating the above cyclic operation. In addition, the gripper element is positively prevented from any lateral movement relative to the carrier chains by the provision of set screws 39 as at 39 in FIGS. 1920.

Thus, specifically in FIG. 18, gripper elements 28 are kept in their outwardly urged position when traveling along in their off-service conditions. When, however. they arrive nearly at the termination of the leading corner, corner zone, of the corresponding circulating passage and are about to travel along the longest horizontal passage, each cooperative couple of gripper elements belonging to both circulating systems are brought into contact with each other at point P, as described hereinbefore, thus forming a gripper 66. The gripper 66 reduces then in its height under the influence of compressive force acting therein and against the action of springs 37 and arrives at point P, wherein the cooperating gripper elements are brought into perfect registry with each other and under full pressure exerted by said springs, as again set forth hereinbefore. If the fibrous material is fed into the machine at the point P, it is subjected to a positive overfeed by the engagement and contraction of the cooperating gripper elements. Thence, the gripper advances along the straight passage or zone, extending between two opposite sets of

chain wheels

13, 14 and 17, 18, during which the fiber bundles are subjected to the secondary heat treatment. For this purpose, the straight zone is provided with heating medium supplying means, as will be described in more detail hereinafter.

Adjustment of the length H to meet the occasional requirement may be preferably carried into effect by

Claims

1. An elongated fibrous unit having substantially invariable denier and comprising repeating longitudinal segments having different shrinkage potentials but all being oriented, whereby said fibrous unit upon subsequent treatment to induce shrinkage will shrink more at some of said longitudinal segments than at other of said longitudinal segments, and said segments being disposed alternately axially of said elongated unit.

2. The fibrous unit of claim 1, wherein said repeating longitudinal segments are of two different shrinkage potentials, some of said segments being of relatively high shrinkage potential and the other of said segments being of relatively low shrinkage potential.

3. The fibrous unit of claim 2, wherein said high and low shrinkage potential segments alternate.

4. The fibrous unit of claim 2, wherein said relatively high shrinkage potential segments are of a different length than said relatively low shrinkage potential segments.

5. A bulky yarn comprising a plurality of the fibrous units defined in claim 2 said fibrous units being adjacent one another and interlocked at spaced points along their length and portions of said fibrous units between the same successive interlocking points differing in configuration from fibrous unit to therewith interlocked fibrous unit, said configuration varying from substantially linear to buckled, said substantially linear configuration corresponding to said relatively high shrinkage potential segments and said substantially buckled configuration corresponding to said relatively low shrinkage potential segments.

6. A bulky fabric comprising yarn defined in claim 5 knitted.

7. A bulky fabric comprising yarn defined in claim 5 woven.

8. The fibrous unit of claim 1, wherein the length of the segments varies randomly from segment to segment.

9. A yarn comprising a plurality of the fibrous units defined in claim 1 and which will become bulky upon treatment to induce shrinkage of the fibrous units, said fibrous units are adjacent one another and interlocked at spaced points along their length so that at said points substantial longitudinal movement of immediately adjacent fibrous units with respect to one another is substantially restRained.

10. The yarn defined in claim 9, wherein portions of said fibrous units between the same successive interlocking points differ in shrinkage potential from fibrous unit to therewith interlocked fibrous unit.

11. The yarn defined in claim 10, wherein said interlocking comprises entanglement of said fibrous units with one another at said points.

12. The yarn defined in claim 10, wherein said interlocking comprises twisting of said fibrous units about one another at said points.

13. A fabric comprising a plurality of the yarns defined in claim 9 knitted and which fabric will become bulky upon said treatment.

14. A fabric comprising a plurality of the yarns defined in claim 9 woven and which fabric will become bulky upon said treatment.

15. A fabric comprising a plurality of the fibrous units defined in claim 1, said fibrous units comprising a web wherein said fibrous units intersect one another and are interlocked at said intersections and portions of said fibrous units between the same successive interlocked intersections differ in shrinkage potential from fibrous unit to therewith interlocked fibrous unit.

16. Fibrous material for use in high bulk textile products, said material comprising a plurality of single fibers having substantially invariable denier and each having in an axial direction alternately high shrinkage portions and low shrinkage portions but all being oriented, the high shrinkage portions having the capability of shrinkage to a greater extent than the low shrinkage portions upon being subjected to relaxation treatment after being prepared into yarn and fabrics so as to make the low shrinkage portions bulk out by the shrinkage of the high shrinkage portions.

17. Fibrous material according to claim 16, in which each single fiber has in the direction of its fiber axis a series of different zones comprising a first zone having the alternate high shrinkage portions and low shrinkage portions which have different ratio of portion lengths and other zones also having the alternate high shrinkage portions and low shrinkage portions having different relative ratios of portion lengths to corresponding portions of the first zone.

18. A yarn comprising a plurality of fibrous units having substantially invariable denier, said units comprising repeating longitudinal segments having different shrinkage potentials but all being oriented, whereby said fibrous units upon subsequent treatment to induce shrinkage will shrink more at some of said longitudinal segments than at other of said longitudinal segments, and said segments being disposed alternately axially of said units.