CN107849750B

CN107849750B - Method for manufacturing tow band, tow band manufacturing device and method for manufacturing cigarette filter

Info

Publication number: CN107849750B
Application number: CN201580082122.2A
Authority: CN
Inventors: 岩本尚久; 新屋忠道; 府藤笃; 伊藤弘
Original assignee: Daicel Corp
Current assignee: Daicel Corp
Priority date: 2015-07-31
Filing date: 2015-07-31
Publication date: 2020-05-22
Anticipated expiration: 2035-07-31
Also published as: WO2017021994A1; CN107849750A; JPWO2017021994A1; JP6276897B2

Abstract

The invention provides a method for manufacturing a tow band, which comprises the following steps: the method comprises a step of conveying a plurality of filaments to the downstream side in the conveying direction by bringing the plurality of filaments to be conveyed into contact with the peripheral surface of a godet roller (6) that is rotating, and a step of inserting the plurality of filaments conveyed by the godet roller (6) between the pair of nip rollers (16, 17) that are rotating and crimping the plurality of filaments in a crimping device (9) that has the pair of nip rollers (16, 17) and is disposed on the downstream side in the conveying direction from the godet roller (6). The plurality of filaments has a filament denier of 5 or more and 15 or less, and a total denier of 10000 or more and 25000 or less. A plurality of filaments are inserted between a pair of nip rollers (16, 17) in a loose state to a degree that they can be conveyed.

Description

Method for manufacturing tow band, tow band manufacturing device and method for manufacturing cigarette filter

Technical Field

The present invention relates to a method for manufacturing a tow band, a tow band manufacturing apparatus, and a method for manufacturing a cigarette filter.

Background

The cigarette filter can be manufactured using, for example, a tow band using a plurality of filaments such as cellulose acetate fibers. In a tow band manufacturing apparatus, as disclosed in patent document 1, for example, a plurality of filaments spun using a spinning tube are integrated by a godet roll to form a yarn, and the plurality of yarns are further integrated while being guided in a predetermined direction by a guide pin to form a yarn bundle, and are conveyed to a crimping apparatus. In the crimping device, the yarn bundle is inserted between a pair of nip rollers and is pressed into a stuffing box provided on the downstream side in the conveying direction of the pair of nip rollers, whereby the yarn bundle is crimped. The tow band thus obtained is dried and folded into a bundle, and packed in a packaging container.

In a filter rod making apparatus (also referred to as a plug (plug) winder), as disclosed in patent document 2, for example, a tow band continuously fed out from a packing container is formed into a rod shape by opening and impregnating a plasticizer. Thereafter, a plug (also referred to as a plug) is manufactured by winding a wrapping paper around the outer periphery of the tow band. Cigarette filters are manufactured by cutting the filter rod into given lengths.

In recent years, slim cigarettes having a smaller diameter than that of ordinary cigarettes, such as "slim" cigarettes, "ultrafine cigarettes" or "extra-fine cigarettes," have been manufactured. The tow band used for manufacturing the filter of a slim type cigarette has FD (filament denier) larger and TD (total denier) smaller than those of tow bands used for manufacturing the filter of a general type cigarette.

Documents of the prior art

Patent document

Patent document 1: japanese Kokai publication 2008-504457

Patent document 2: japanese patent laid-open publication No. 2003-38157

Disclosure of Invention

Problems to be solved by the invention

When producing a tow band having a large FD, the yarn is less likely to be crimped in the crimping device, and hence crimping unevenness may occur. When a cigarette filter is manufactured using a tow band in which the crimping unevenness occurs, there is a concern that the coefficient of variation (PDCv) of the ventilation resistance of the cigarette filter becomes large, and the quality of the cigarette filter is deteriorated.

Accordingly, an object of the present invention is to reduce variation in ventilation resistance of a cigarette filter by suppressing uneven crimping of a tow band when the cigarette filter is manufactured using a tow band having a large FD and a small TD.

Means for solving the problems

The method for manufacturing a tow band according to an embodiment of the present invention includes: and a step of crimping the plurality of filaments conveyed by the godet rollers by inserting the plurality of filaments between the pair of rotating nip rollers, wherein the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to an extent that they can be conveyed, and wherein the filament denier of the plurality of filaments is 5 or more and 15 or less and the total denier is 10000 or more and 25000 or less.

According to the above method, when a tow band is manufactured using a plurality of filaments having a filament denier of 5 or more and 15 or less and a total denier of 10000 or more and 25000 or less, the plurality of filaments are inserted between a pair of nip rollers in a loose state to the extent that they can be conveyed. This prevents a strong tension from acting on the plurality of filaments in the conveying direction between the pair of nip rollers, and the plurality of filaments are less likely to slip against the peripheral surfaces of the nip rollers between the pair of nip rollers. Therefore, the plurality of filaments can be appropriately crimped while suppressing unevenness in crimping. Therefore, in the cigarette filter manufactured by using the tow band including the plurality of filaments, the variation of the ventilation resistance can be reduced and the ventilation resistance can be stabilized. This can prevent the quality of the cigarette filter from being degraded.

Further, the tension applied to the plurality of filaments in the conveying direction may be adjusted between the godet roller and the pair of nip rollers, so that the plurality of filaments may be inserted between the pair of nip rollers in a state of being loosened to an extent that they can be conveyed.

According to this method, the tension applied to the plurality of filaments in the conveying direction is adjusted between the godet roller and the pair of nip rollers, whereby the plurality of filaments can be easily adjusted to a state in which they are loosened to a degree that enables conveyance when they are inserted into the pair of nip rollers.

Further, the peripheral speed ratio V2/V1 between the peripheral speed V1 of the godet roller and the peripheral speed V2 of the pair of nip rollers may be set to a value in the range of 1.02 to 1.04. By setting the value of the circumferential speed ratio V2/V1 in this way, the plurality of filaments can be easily adjusted to a state in which they are loosened to such an extent that they can be conveyed when they are inserted into the pair of nip rollers.

Further, between the godet roller and the pair of nip rollers, the plurality of filaments may be conveyed toward the downstream side in the conveying direction while being guided by bringing the plurality of filaments into contact with 1 or more guide pins.

According to this method, the conveying direction of the plurality of filaments can be changed by guiding the plurality of filaments using 1 or more guide pins. Further, by adjusting the tension applied to the plurality of filaments in the conveying direction so that the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to such an extent that the plurality of filaments can be conveyed, the frictional resistance of the plurality of filaments against the guide pins can be reduced, and the plurality of filaments are prevented from being damaged by contact with the guide pins.

Further, the plurality of filaments may be inserted between the pair of nip rollers in a state of being loosened to such an extent that the plurality of filaments can be conveyed, so that a variation coefficient of the number of crimps of the plurality of filaments crimped by the crimping apparatus may be set to a value in a range of 2.0% to 3.0%. By using a tow band in which the coefficient of variation in the number of crimps of the tow band is suppressed within a predetermined range, the variation in the ventilation resistance of the cigarette filter can be reduced favorably.

In addition, a method for manufacturing a cigarette filter according to an embodiment of the present invention is a method for manufacturing a cigarette filter using a crimped tow band, and by using the tow band manufactured by any of the above manufacturing methods, a coefficient of variation in ventilation resistance of the cigarette filter is set to a value in a range of 2.0% to 3.0%. Thus, the cigarette filter can be manufactured with stable quality with small variation in ventilation resistance.

Further, a tow band manufacturing apparatus according to an embodiment of the present invention includes: a godet roller for conveying the plurality of filaments to a downstream side in a conveying direction by bringing the plurality of filaments to be conveyed into contact with a rotating peripheral surface; and a crimping device which has a pair of nip rollers, is provided on the downstream side of the godet rollers in the conveying direction, and crimps the plurality of filaments conveyed by the godet rollers by inserting the plurality of filaments between the pair of nip rollers in rotation. The plurality of filaments have a filament denier of 5 or more and 15 or less and a total denier of 10000 or more and 25000 or less, and the tow band manufacturing apparatus is configured such that the plurality of filaments are inserted between the pair of nip rollers in a loose state to a degree that they can be transported.

According to the above configuration, when a tow band is manufactured using a plurality of filaments having a filament denier of 5 or more and 15 or less and a total denier of 10000 or more and 25000 or less, the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to a degree that enables conveyance, and therefore, it is possible to prevent a strong tension from acting on the plurality of filaments in the conveyance direction between the pair of nip rollers, so that the plurality of filaments are less likely to slide with respect to the peripheral surface of each nip roller between the pair of nip rollers. Therefore, the plurality of filaments can be appropriately crimped while suppressing unevenness in crimping. Therefore, in the cigarette filter manufactured by using the tow band including the plurality of filaments, the ventilation resistance can be stabilized, and the variation of the ventilation resistance can be reduced. This can prevent the quality of the cigarette filter from being degraded.

In addition, the following configuration is also possible: the tension applied to the plurality of filaments in the conveying direction is adjusted between the godet roller and the pair of nip rollers, so that the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to an extent that they can be conveyed.

According to the above configuration, by adjusting the tension applied to the plurality of filaments in the conveying direction between the godet roller and the pair of nip rollers, the plurality of filaments can be easily adjusted to a state in which they are loosened to a degree that they can be conveyed when they are inserted into the pair of nip rollers.

Further, the peripheral speed ratio V2/V1 between the peripheral speed V1 of the godet roller and the peripheral speed V2 of the pair of nip rollers may be set to a value in the range of 1.02 to 1.04.

By setting the value of the circumferential speed ratio V2/V1 in this way, the plurality of filaments can be easily adjusted to a state in which they are loosened to such an extent that they can be conveyed when they are inserted into the pair of nip rollers.

Further, the yarn feeding device may further include 1 or more guide pins, and the 1 or more guide pins may be disposed between the godet roller and the pair of nip rollers, and may contact the plurality of filaments to guide the plurality of filaments and convey the plurality of filaments to a downstream side in a conveying direction.

According to the above configuration, by guiding the plurality of filaments using 1 or more guide pins, the conveying direction of the plurality of filaments can be changed. Further, by adjusting the tension applied to the plurality of filaments in the conveying direction so that the plurality of filaments can be inserted between the pair of nip rollers in a state of being loosened to such an extent that the plurality of filaments can be conveyed, the frictional resistance of the plurality of filaments against the guide pin can be reduced, and the plurality of filaments can be prevented from being damaged by contact with the guide pin.

In addition, the following configuration is also possible: the plurality of filaments are inserted between the pair of nip rollers in a loose state to a degree that the plurality of filaments can be conveyed, so that the coefficient of variation in the number of crimps of the plurality of filaments crimped by the crimping device can be set to a value in a range of 2.0% to 3.0%. By using the tow band in which the coefficient of variation in the number of crimps of the tow band is suppressed within a predetermined range, the variation in the ventilation resistance of the cigarette filter can be reduced favorably.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, when a cigarette filter is manufactured using a tow band having a large FD and a small TD, variation in the air flow resistance of the cigarette filter can be reduced by suppressing uneven crimping of the tow band.

Drawings

FIG. 1 is an overall view of a tow band manufacturing apparatus.

Fig. 2 is a partial view showing a conveyance path between a godet roller and a pair of nip rollers.

FIG. 3 is an overall view of a filter rod making apparatus.

Description of the symbols

1 tow band manufacturing device

6 godet roller

7. 8 guide pin

9 crimping device

16. 17 nip roll

100 filaments

103 tow band

106 cigarette filter

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience, a tow band used for manufacturing a filter of a general cigarette is referred to as a "tow band for RTC". The tow band used for manufacturing a filter of a slim cigarette is referred to as an "STC tow band".

(embodiment mode)

[ apparatus for producing tow band ]

Fig. 1 is an overall view of a tow band manufacturing apparatus 1. The tow band manufacturing apparatus 1 spins a plurality of filaments 100 having a filament denier of 5 or more and 15 or less and a total denier of 10000 or more and 25000 or less, and manufactures a tow band 103 for STC from the plurality of filaments 100.

As shown in fig. 1, a tow band manufacturing apparatus 1 includes: a mixer 2, a filtering device 3, a spinning device 4, a oiling device 5, a godet roller 6, guide pins 7, 8, a crimping device (crimper) 9, a drying device 10, and a baling device 11. The tow band manufacturing apparatus 1 further includes a control unit, not shown.

The mixer 2 includes a mixing vessel 12 and a stirrer 13, and adjusts a spinning dope containing a material of the filaments 100 (in the present embodiment, a material of cellulose acetate fibers). The filtering device 3 filters the spinning dope supplied from the mixer 2 to remove impurities. The spinning device 4 includes a plurality of spinning tubes 14 arranged side by side, a spinneret 15 provided at an upper portion of each spinning tube 14, and a spinning pump not shown, and spins a plurality of filaments 100.

In the spinning device 4, for example, a spinning pump is driven based on a dry spinning method, the spinning dope passed through the filter device 3 is fed to each of the spinnerets 15, and is discharged downward from a plurality of spinning holes formed in each of the spinnerets 15 into the spinning tube 14, thereby spinning a plurality of filaments 100. The plurality of filaments 100 are integrally combined while being conveyed from each spinning tube 14 to the downstream side in the conveying direction, thereby forming a yarn 101.

Oiling devices 5 are disposed below the respective spinning tubes 14 to adhere the oil emulsion to the yarn 101. A fiber finish is included in the oil emulsion along with water. The godet rollers 6 are disposed below the respective oiling devices 5, are driven to rotate, and convey the yarn 101 to the downstream side in the conveying direction by contacting the peripheral surface. The godet roller 6 is driven to rotate at the peripheral speed V1 by the control unit.

The guide pins 7 are disposed so as to extend in the vertical direction on the downstream side in the conveyance direction of the godet rollers 6. Each guide pin 7 guides the yarn 101 to the downstream side in the conveying direction by coming into contact with the yarn 101 conveyed by each godet roller 6. The guide pins 8 are disposed so as to extend in the vertical direction on the downstream side in the conveying direction of the guide pins 7. Each guide pin 8 guides the yarn 101 to the downstream side in the conveying direction by coming into contact with the yarn 101 conveyed by each guide pin 7. The yarns 101 are conveyed to the downstream side in the conveying direction and are united in the horizontal direction to form a yarn bundle 102. The yarn bundle 102 is conveyed to the crimping device 9.

In the tow band manufacturing apparatus 1, the yarn bundles 102 may be formed by integrating the respective yarns 101 in a vertical direction. At least one of the guide pins 7 and 8 may be used in accordance with the conveying direction of the conveying yarn bundle 102. The number of the guide pins 7 and 8 is not limited, and may be plural. The guide pins 8 may be arranged to extend in the horizontal direction perpendicular to the conveying direction.

The crimper 9 is a stuffing box type, and has a pair of nip rolls (also referred to as feed rolls or press rolls) 16 and 17 and a stuffing box 18, and crimps the yarn bundle 102. The pair of nip

rollers

16 and 17 are arranged to be axially supported in parallel and are rotationally driven, whereby the yarn bundle 102 is inserted into the nip portion N between the pair of nip

rollers

16 and 17. The pair of nip

rollers

16 and 17 are rotationally driven at the peripheral speed V2 by the control unit. The stuffing box 18 has a 1 st plate material 19, a 2 nd plate material 20, and a 3 rd plate material 21, and is disposed on the downstream side in the conveying direction of the pair of

pinch rollers

16, 17. The plate surfaces of the 1 st plate member 19 and the 2 nd plate member 20 are arranged to face each other. The 3 rd plate member 21 is disposed between the 1 st plate member 19 and the 2 nd plate member 20 so as to extend from the 1 st plate member 19 to the 2 nd plate member 20, and an end portion on the downstream side in the conveying direction is biased so as to press the plate surface of the 2 nd plate member 20. The 1 st plate member 19, the 2 nd plate member 20, and the 3 rd plate member 21 are flat plate-like members as an example, but at least one of them may be a bent plate-like member.

Fig. 2 is a partial view showing the conveyance path L between the godet roller 6 and the pair of nip

rollers

16, 17. Fig. 2 shows the godet roller 6 and the guide pins 7, 8 disposed closest to the nip N. In the tow band manufacturing apparatus 1, the peripheral speed ratio V2/V1 of the peripheral speed V1 of each godet roller 6 and the peripheral speed V2 of the pair of nip

rollers

16 and 17 is set as appropriate, and is set to the same value slightly larger than 1.00 as an example. Specifically, each circumferential speed ratio V2/V1 is set to a value in the range of 1.02 or more and 1.04 or less (here, 1.03). As a result, a weak tension is applied to the yarn bundle 102 in the conveying direction in the conveying path L, and the yarn bundle 102 is inserted into the nip portion N in a loose state to such an extent that it can be conveyed. Fig. 2 shows a case where the yarn bundle 102 in a state of being loosened to such an extent that the yarn bundle can be conveyed passes through a position deviated from a straight line X passing through the lower portion of the peripheral surface of the guide pin 8 and the nip portion N in the conveyance path L and is conveyed). The term "degree of transportability" as used herein means: during the operation of the tow band manufacturing apparatus 1, the yarn 101 and the yarn bundle 102 can be conveyed normally in the tow band manufacturing apparatus 1 without the yarn 101 being separated from or entangled with the guide pins 7 and 8 and without the yarn bundle 102 being separated from or entangled with the godet roller 6 or the pair of nip

rollers

16 and 17.

When inserted between the pair of nip

rollers

16 and 17, the yarn bundle 102 is subjected to a fine primary crimp at the nip portion N, and then released from the nip portion N and pressed into the stuffing box 18. As shown in fig. 1, the inner space of the stuffing box 18 is narrowed toward the downstream side in the conveying direction by the end portion on the downstream side in the conveying direction of the 3 rd plate member 21 pressing the plate surface of the 2 nd plate member 20. The yarn bundle 102 temporarily stays while being vertically meanderly bent in the stuffing box 18, and then passes between the 2 nd plate member 20 and the 3 rd plate member 21 and is discharged to the downstream side in the conveying direction. This makes it possible to obtain the tow band 103 to which the high-order crimp is applied. The number of crimps of the yarn bundle 102 can be set in the crimper 9. The number of crimps is the number of peaks given to the yarn 102 per unit length in the conveying direction, and is set such that the number of peaks given to the yarn 102 per 10 inches in the conveying direction is 300, for example.

The drying device 10 dries the tow band 103 after passing through the crimping device 9, thereby removing the residual solvent and moisture in the tow band 103. The baling device 11 folds and compresses the tow band 103 after the drying device 10 passes through into a bundle shape, and bales into a given baling box 25.

[ Filter rod manufacturing apparatus ]

Fig. 3 is an overall view of the filter rod making apparatus 30. The filter rod making apparatus 30 is used to make cigarette filters 106 using a tow band 103. As shown in fig. 3, the filter rod making apparatus 30 includes: a first opening injection device 31, a second opening injection device 32, a pre-tensioning roller pair 33, a first opening roller pair 34, a second opening roller pair 35, a third opening injection device 36, an impregnation device 37, a conveying roller pair 38, a transport injection device 39, a funnel (funnel)40, a bobbin 41, and a rotary blade 42.

The first opening jet device 31, the second opening jet device 32, and the third opening jet device 36 are disposed at positions spaced apart from each other in the filter rod making apparatus 30, and jet-shaped air is jetted to the bundle-shaped tow band 103 continuously fed from the packing box 25 to open the tow band 103 in the width direction (direction orthogonal to the conveying direction). The first opening jet device 31 and the second opening jet device 32 are disposed on the upstream side in the conveying direction than the pair of pre-tension rollers 33, and the third opening jet device 36 is disposed on the downstream side in the conveying direction than the pair of second opening rollers 35.

The pre-tension roller pair 33 has a pair of rollers 43 and 44, and the tow band 103 is inserted between the pair of rollers 43 and 44 to apply tension to the tow band 103 in the conveying direction. The first opening roller pair 34 has a pair of

rollers

45 and 46, and the second opening roller pair 35 has a pair of

rollers

47 and 48. The first opening roller pair 34 and the second opening roller pair 35 are arranged side by side in the conveying direction, and the tow band 103 is inserted between the pair of

rollers

45 and 46 and between the pair of

rollers

47 and 48, respectively. The first pair of opening rollers 34 and the second pair of opening rollers 35 open the tow band 103 in the conveyance direction and the width direction.

The impregnation device 37 impregnates the tow band 103 after passing through the third opening fiber injection device 36 with the plasticizer. The plasticizer is triacetin as an example, but is not limited thereto. The conveying roller pair 38 has a pair of

rollers

49 and 50, and conveys the tow band 103 having passed through the impregnation device 37 to the downstream side in the conveying direction.

The transportation and injection device 39 compresses the transported tow band 103 into a cylindrical shape by using injected air, and transports the tow band to the hopper 40. The hopper 40 conveys the tow band 103 to the downstream side in the conveying direction while winding the tow band into a spiral shape. The bobbin 41 forms the tow band 103 into a cylindrical shape, and the roll paper 104 is wound around the outer periphery of the tow band 103. The rotary blade 42 cuts a tow band 103 formed into a cylindrical shape and wound with a roll paper 104 at the outer periphery into a given length. A filter plug 105 is manufactured by cutting the tow band 103 with the rotary blade 42, and a cigarette filter 106 for cigarettes of the slim type is manufactured by cutting the filter plug 105 to a given length.

As described above, in the tow band manufacturing apparatus 1, by setting the value of the circumferential speed ratio V2/V1 of each of the godet rollers 6 and the pair of nip

rollers

16 and 17 to a value in the range of 1.02 or more and 1.04 or less (here, 1.03) as an example, a weak tension is applied to the yarn bundle 102 in the conveyance direction in the conveyance path L between the godet roller 6 and the pair of nip

rollers

16 and 17. This makes it possible to stably convey the yarn bundle 102 in the conveyance path L while preventing positional variation of the yarn bundle.

In the tow band manufacturing apparatus 1, the yarn bundle 102 is inserted between the pair of nip

rollers

16 and 17 in a loose state to such an extent that it can be conveyed. Therefore, when the yarn bundle 102 is inserted between the pair of nip

rollers

16 and 17, a strong tension is applied to the yarn bundle 102 in the conveyance direction, and the yarn bundle 102 is prevented from being easily slid with respect to the peripheral surfaces of the nip

rollers

16 and 17 between the pair of nip

rollers

16 and 17. Therefore, the yarn bundle 102 can be properly crimped while suppressing the unevenness of crimping. Therefore, the tow band 103 can be manufactured with reduced variation in the number of crimps and with uniform crimps. Specifically, the tow band 103 can be manufactured in which the coefficient of variation in the number of crimps is suppressed to a value in the range of 2.0% to 3.0%.

Further, by adjusting the tension applied to the yarn bundle 102 in the conveyance direction between the godet roller 6 and the pair of nip

rollers

16 and 17, the yarn bundle 102 can be easily adjusted to a state in which it is loosened to a degree that it can be conveyed when it is inserted between the pair of nip

rollers

16 and 17. Specifically, by setting the circumferential speed ratio V2/V1 to a value in the range of 1.02 or more and 1.04 or less, the yarn bundle 102 can be easily adjusted to a state in which it is loosened to a degree that it can be conveyed when it is inserted between the pair of nip

rollers

16 and 17.

In the tow band manufacturing apparatus 1, the tension applied to the yarn bundle 102 in the conveying direction in the conveying path L is adjusted so that the yarn bundle 102 is inserted between the pair of nip

rollers

16 and 17 in a loose state to such an extent that the yarn bundle can be conveyed, and therefore the frictional resistance of the yarn bundle 102 against the guide pins 7 and 8 is reduced. This makes it difficult for the yarn bundle 102 to be damaged by contact with the guide pins 7 and 8, and reduces the amount of filament (fly) generated by damage to the yarn bundle 102.

In the conventional tow band manufacturing apparatus, when the position of the yarn bundle conveyed in the conveyance path between the godet roller and the pair of pinch rollers is changed to cause the uneven winding of the tow band, it is conceivable to increase the tension applied to the yarn bundle conveyed in the conveyance path in the conveyance direction, for example, as a general solution to this problem. However, the inventors of the present application have found that there is room for improvement in a measure for solving the crimp unevenness of the tow band when the tow band for STC is manufactured. As a result of intensive studies, the present inventors have found that uneven crimping of a tow band can be appropriately suppressed by inserting a yarn bundle between a pair of nip rollers of a crimping device in a state where the yarn bundle is loosened to such an extent that the yarn bundle can be conveyed. The present embodiment has been completed based on these findings, and based on a concept different from the general concept, by allowing the positional change of the yarn bundle 102 in the conveyance path L to some extent and inserting the yarn bundle 102 between the pair of nip

rollers

16 and 17 in a state of being loosened to an extent that the yarn bundle can be conveyed, the unevenness in crimping in the tow band 103 is favorably suppressed.

In the filter plug manufacturing apparatus 30, the filter plug 105 is manufactured using the tow band 103 that has been uniformly crimped while suppressing crimping unevenness in the crimping apparatus 9. Thus, a cigarette filter 106 in which PDCv was well suppressed was manufactured. Specifically, in the filter rod manufacturing apparatus 30, by manufacturing the filter rod 105 using the tow band 103, a cigarette filter 106 in which the PDCv is suppressed to a value in the range of 2.0% or more and 3.0% or less can be manufactured as an example. This makes it possible to manufacture a cigarette filter 106 with stable ventilation resistance. This can prevent the quality of the cigarette filter 106 from being degraded.

In addition, in the tow band manufacturing apparatus 1, since the tow band 103 can be manufactured while reducing the amount of filament generated, in the filter rod manufacturing apparatus 30, it is possible to suppress the filament from absorbing the plasticizer in the impregnation device 37 and mixing into the cigarette filter 106 to generate melt holes (meltholes). This can further prevent the quality of the cigarette filter 106 from being degraded.

(measurement test)

In the tow band manufacturing apparatus, when the peripheral speed ratio V2/V1 of each of the godet rollers and the pair of nip rollers was changed, the positional variation of the yarn bundle with respect to the guide pin and the variation of the PDCv of the cigarette filter were examined by a measurement test.

As the samples for the measurement test, a tow band for RTC was produced using a plurality of filaments having a Y-shaped cross section with FD of 3.0, and a tow band for STC was produced using a plurality of filaments having a Y-shaped cross section with FD of 6.0. The TD of the RTC tow band was 30000 and the TD of the STC tow band was 17000. When the tow band for RTC is manufactured, the peripheral speed ratio V2/V1 is uniformly set to any one of 1.03, 1.04, and 1.05. When manufacturing the tow band for STC, the circumferential speed ratio V2/V1 was uniformly set to 1.03 or 1.05.

When manufacturing the tow band for RTC, the set value of the number of crimps per 10 inches of the tow band in the crimping apparatus is set to 345. When manufacturing the tow band for STC, the set value of the number of crimps per 10 inches of the tow band in the crimping apparatus was set to 300. In the production of each tow band, a tester visually confirmed the positional variation of the yarn bundle with respect to the specific guide pins arranged to extend in the vertical direction, and evaluated as "a" if the positional variation of the end of the yarn bundle in the vertical direction for 1 minute was less than 3mm and evaluated as "B" if the positional variation was 3mm or more.

Using the tow band of each sample manufactured as described above, a plurality of filter rods were manufactured by a filter rod manufacturing apparatus (KDF-3/AF-3) manufactured by Hauni corporation (germany). The length of the filter rod produced using the tow band for RTC was set to 120mm, the circumference was set to 24.4mm, and the filling amount NTW was set to 0.570 g. The length of each filter rod manufactured using a tow band for STC was set to 120mm, the circumference was set to 16.7mm, and the filling amount NTW was set to 0.300 g.

The values of PD (air flow resistance) of the plurality of filter rods of each sample manufactured were calculated. Further, the value of Cv was calculated from the fluctuation in the standard deviation of the ventilation resistance values of 1 group of filter rods, with 15 filter rods of each sample set as 1 group. Further, 10 sets of Cv values were averaged to calculate PDCv. The results of the measurement test are shown in table 1.

[ Table 1]

As shown in table 1, when samples 1 and 4 for manufacturing the STC tow band were compared, the PDCv of the filter rod was 3.8% in sample 4 in which the value of each peripheral speed ratio V2/V1 was set to 1.05, while the PDCv of the filter rod was suppressed to 2.5% in sample 1 in which the value of each peripheral speed ratio V2/V1 was set to 1.03. As a cause of this, in sample 4, since the value of each peripheral speed ratio V2/V1 was set to be excessively larger than the reasonable value, the tension applied to the plurality of filaments in the conveying direction became excessively large, and the yarn bundle slipped in the conveying direction against the peripheral surface of each nip roller between the pair of nip rollers, and hence the uneven crimping occurred. On the other hand, in sample 1, since the value of each peripheral speed ratio V2/V1 was set to a reasonable value, the tension applied to the yarn bundle in the conveying direction was small, and the yarn bundle was inserted between the pair of nip rollers in a state of being loosened to such an extent that it could be conveyed, and the plurality of filaments were appropriately crimped. It is noted that the evaluation of the positional variation of the yarn bundles with respect to the guide pins in samples 1 and 4 is a, and it is understood that the yarn bundles can be stably conveyed in samples 1 and 4 within the range in which the present test is performed.

Next, if samples 2, 3 and 5 for manufacturing a tow band for RTC are compared, the values of PDCv are in the following order: sample 2, in which the value of each peripheral speed ratio V2/V1 was set to 1.04, was the lowest, followed by sample 3, in which the value of each peripheral speed ratio V2/V1 was set to 1.03, followed by sample 5, in which the value of each peripheral speed ratio V2/V1 was set to 1.05. From the test results, it is considered that the RTC tow band tends to increase PDCv around the minimum value of PDCv which is considered to be in the vicinity of the PDCv value of sample 2. As a cause of this, when the value of each peripheral speed ratio V2/V1 is set to be excessively larger than an appropriate value, the yarn bundle slides in the conveying direction between the pair of nip rollers with respect to the peripheral surfaces of the nip rollers, and thus the uneven crimping is increased. Further, in samples 2, 3 and 5, since the evaluation of the positional variation of the yarn bundle of sample 3 is B, it is understood that when the values of the peripheral speed ratios V2/V1 are set to values excessively smaller than the reasonable values, the positional variation of the yarn bundle in the conveyance path becomes large, and therefore the state of the yarn bundle when inserted between the pair of nip rollers becomes unstable, and the unevenness in crimping becomes large. As one of the reasons why the value of PDCv was not sufficiently reduced in sample 3, it is considered that the FD of the RTC tow band was 3.0, and therefore, when the peripheral speed ratio V2/V1 was set to be small, the positional variation of the yarn bundle in the conveyance path was likely to increase, and the state of the yarn bundle when inserted between the pair of nip rollers became unstable.

Since the FD of the STC tow band is 6.0, even if the peripheral speed ratio V2/V1 is set to be slightly smaller than the PDCv minimum value, the positional variation of the yarn bundle in the conveyance path is unlikely to increase, and the yarn bundle is unlikely to be unevenly crimped. Therefore, in the STC tow band, in order to reduce PDCv while suppressing uneven crimping, it is considered that a large number of filaments are loosened to a degree that enables conveyance when inserted between a pair of nip rollers.

The present invention is not limited to the above embodiments, and the technical means and methods thereof may be changed, added, or deleted without departing from the scope of the present invention.

Industrial applicability

As described above, according to one embodiment of the present invention, when a cigarette filter is manufactured using a tow band having a large FD and a small TD, the tow band can be prevented from being unevenly crimped, and variation in ventilation resistance of the cigarette filter can be reduced. Therefore, it is advantageous to use the method for producing a tow band, the tow band production apparatus, and the method for producing a cigarette filter, which are widely used to achieve the effect.

Claims

1. A method of manufacturing a tow band, comprising:

a step of conveying the plurality of filaments to the downstream side in the conveying direction by bringing the plurality of filaments to be conveyed into contact with the peripheral surface of the godet roller that is rotating, and

a step of, in a crimping device which has a pair of nip rollers and is disposed on the downstream side in the conveyance direction from the godet roller, inserting a plurality of filaments conveyed by the godet roller between the pair of nip rollers while rotating and crimping the filaments,

the plurality of filaments have a filament denier of 5 or more and 15 or less and a total denier of 10000 or more and 25000 or less,

wherein the plurality of filaments are inserted between the pair of nip rollers in a loose state to a degree that they can be conveyed.

2. The method of manufacturing a tow band according to claim 1, wherein the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to an extent that they can be conveyed by adjusting tension applied to the plurality of filaments in a conveying direction between the godet roller and the pair of nip rollers.

3. The method for producing a tow band according to claim 1 or 2, wherein a peripheral speed ratio V2/V1 between a peripheral speed V1 of the godet roller and a peripheral speed V2 of the pair of nip rollers is set to a value in a range of 1.02 or more and 1.04 or less.

4. The method of manufacturing a tow band according to claim 1 or 2, wherein the plurality of filaments are conveyed to a downstream side in a conveying direction while being guided by contacting the plurality of filaments with 1 or more guide pins between the godet roller and the pair of nip rollers.

5. The method of manufacturing a tow band according to claim 1 or 2, wherein the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to such an extent that they can be conveyed, so that a coefficient of variation in the number of crimps of the plurality of filaments crimped by the crimping device can be set to a value in a range of 2.0% to 3.0%.

6. A method for manufacturing a cigarette filter using a crimped tow band, the method comprising:

by using the tow band produced by the production method according to any one of claims 1 to 5, the coefficient of variation in ventilation resistance of the cigarette filter is set to a value in the range of 2.0% to 3.0%.

7. A tow band manufacturing device is provided with:

a godet roller for conveying a plurality of filaments to a downstream side in a conveying direction by bringing the plurality of filaments into contact with a rotating peripheral surface thereof, an

A crimping device which has a pair of nip rollers, is disposed downstream of the godet rollers in the conveying direction, and crimps the plurality of filaments conveyed by the godet rollers by inserting the filaments between the pair of nip rollers during rotation,

the tow band manufacturing apparatus is configured such that the plurality of filaments are inserted between the pair of nip rollers in a loose state to such an extent that they can be conveyed.

8. The tow band manufacturing apparatus according to claim 7, which is configured in such a manner that: the tension applied to the plurality of filaments in the conveying direction is adjusted between the godet roller and the pair of nip rollers, whereby the plurality of filaments are inserted between the pair of nip rollers in a state of being loosened to such an extent that they can be conveyed.

9. The tow band manufacturing apparatus according to claim 7 or 8, wherein a peripheral speed ratio V2/V1 of a peripheral speed V1 of the godet roller to a peripheral speed V2 of the pair of nip rollers is set to a value in a range of 1.02 or more and 1.04 or less.

10. The tow band manufacturing apparatus according to claim 7 or 8, further comprising 1 or more guide pins, wherein the 1 or more guide pins are disposed between the godet roller and the pair of nip rollers, and are in contact with the plurality of filaments to guide the plurality of filaments and convey the plurality of filaments to a downstream side in a conveying direction.

11. The tow band manufacturing apparatus according to claim 7 or 8, which is constructed in the following manner: the plurality of filaments are inserted between the pair of nip rollers in a loose state to a degree that the plurality of filaments can be conveyed, so that the coefficient of variation in the number of crimps of the plurality of filaments crimped by the crimping device can be set to a value in a range of 2.0% to 3.0%.