JP2005320636A - Method for producing stretchable nonwoven fabric for disposable paper diaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a stretchable nonwoven fabric for disposable paper diapers in which functionality and sensuousness required for disposable paper diaper can be improved and a method for producing the disposable paper diaper excellent in functionality, sensuousness and a fitting property, etc., obtained when worn. <P>SOLUTION: The method for producing the stretchable nonwoven fabric for paper diapers comprises arranging an elastic yarn beam-winding body for winding several elastic yarns onto a bobbin in a beam state in which several elastic yarns are parallel arranged at an elastic yarn-feeding position in production process of the stretchable nonwoven fabric for paper diaper, positively rotating the elastic yarn beam-winding body, feeding elastic yarn while reeling the elastic yarn beam and inserting many numbers of elastic yarns fed into spaces between nonwoven fabric and fixing these yarns. The elastic beam winding body for production of stretchable nonwoven fabric for disposable paper diapers is obtained by winding many numbers of elastic yarns on the bobbin in the beam state in which many numbers of elastic yarns are parallel arranged. In the elastic yarn beam winding body, the yarn length (Lm) of wound elastic yarn, yarn number (E) and fineness (Ddtex) satisfy the formula: 1<L/(E×D)<7. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a stretchable nonwoven fabric suitable for producing a paper diaper having excellent appearance aesthetics and excellent fit properties at low cost. More specifically, the present invention relates to an improvement in a method for supplying elastic yarn in a process for producing a stretchable nonwoven fabric for paper diapers.

  Some disposable diapers have a wide variety of structures, but an elastic thread is inserted to improve the fit of the body around the legs, abdomen, waist, etc., or to prevent leakage of urine. Often composed of stretched nonwoven fabric.

  This stretchable nonwoven fabric is a laminate-structured nonwoven fabric having stretchability, in which a plurality of elastic yarns are inserted between nonwoven fabric sheets while being stretched with a predetermined draft, and are fixed between the nonwoven fabric sheets in the stretched state. As an example, there is a stretchable nonwoven fabric produced by arranging a plurality of elastic yarns in parallel between two webs and fixing the elastic yarns by mechanical entanglement between the webs (Patent Document 1). reference). A hot melt adhesive is also used for fixing the elastic yarn between the webs.

  Such stretchable nonwoven fabrics are generally produced in one step during the manufacturing process of disposable diapers. As the elastic yarn, polyurethane elastic yarn or rubber yarn is used, and the elastic yarn is manufactured in the form of a wound body of cheese or the like wound up on a paper tube, or in a state of being hung down in a box, making a disposable diaper. It is supplied to the elastic nonwoven fabric manufacturing process in the process. Since these elastic yarns are fixed in parallel in a stretchable nonwoven fabric for disposable diapers, it is necessary to supply a plurality of elastic yarns simultaneously when producing a stretchable nonwoven fabric having a certain width. .

  For example, when supplying elastic yarn from a wound body, a plurality of the wound bodies are placed on a feeding roller provided in a paper diaper manufacturing machine so that a predetermined draft is positively produced by the rotational speed of the roller. While adjusting the amount of elastic yarn supplied, a plurality of elastic yarns are simultaneously fed in parallel, inserted between nonwoven fabric sheets, and fixed to produce a stretchable nonwoven fabric. In addition, when using a rubber thread suspended from the box, the amount of rubber thread supplied is adjusted so that a predetermined draft is obtained after being wound up by a reel for drawing provided in a paper diaper manufacturing machine. However, a stretchable nonwoven fabric is produced by simultaneously feeding a plurality of rubber yarns in parallel and inserting them between nonwoven fabric sheets and fixing them.

  By the way, in recent years, more advanced functionality and aesthetics have been demanded for disposable diapers. For example, as a fitting property at the time of wearing, a scientific and delicate power design for each part is required to be comparable to women's underwear. Appearance has also become important as an appealing element to consumers. Therefore, it is desired that the elastic yarn to be used is thinned to increase the number of yarns used, and the elastic yarn inserted between the nonwoven fabrics is less noticeable. Furthermore, while maintaining the function of preventing diaper slipping and urine leakage when worn, further improvements are required to make it difficult for the baby's delicate skin to become clamped. It is desired to disperse and equalize the tightening force by making the elastic yarn to be made thinner and a larger number.

  In addition, as shown in FIG. 9, the elastic yarn is supplied in the disposable diaper manufacturing process by using a wound body (12) in which each elastic yarn is individually wound on a paper tube or tube as an elastic yarn of a disposable diaper manufacturing machine. On the feeding roller (11) one by one in series, pull out one elastic thread (Y) from each wound body (12), change the yarn path direction with the guide (13), This is performed by supplying a large number of elastic yarns in parallel.

  In such a conventional elastic yarn feeding method, the number of elastic bobbin bodies (12) to be installed is limited by the length of the feed roller (11), so there is a limit to increasing the number of elastic yarns supplied. There is.

  Therefore, it has been attempted to install a plurality of elastic bobbin bodies in a limited space by arranging a plurality of delivery rollers and dividing them into upper and lower parts and front and rear parts. In this case, in order to make the elastic yarns individually fed from the wound body into a state where a large number of elastic yarns are arranged in parallel at intervals of several millimeters on one plane immediately before being inserted between the nonwoven fabrics. Guides the path of the elastic yarn that is unwound from the elastic bobbin that is divided into multiple stages on the top, bottom, and front and back, where it was not necessary for unwinding from a single feed roller. It is necessary to bend by such as. As a result, there arises a problem that the supply tension of the elastic yarn varies due to the frictional resistance caused by contact with the guide or the like, and it becomes difficult to maintain a stable yarn supply draft. If the yarn feeding draft of the elastic yarns fed in parallel and inserted between the nonwoven fabrics varies between the elastic yarns, the resulting nonwoven fabric has non-uniform stretch properties, making it difficult to obtain a stretch nonwoven fabric with good quality. Therefore, such a yarn feeding method is not preferable in practice.

Japanese Patent No. 3217630

  An object of this invention is to provide the manufacturing method of the elastic nonwoven fabric for paper diapers which can improve the functionality and aesthetics which are calculated | required by a paper diaper goods, without accompanying the productivity deterioration at the time of paper diaper manufacture. That is, it aims at providing the method for manufacturing the paper diaper excellent in functionality, aesthetics, and the fitting property at the time of wearing.

  The present invention employs the following means in order to achieve the object.

  That is, the method for producing a stretchable nonwoven fabric for paper diapers according to the present invention is a method of producing a stretchable nonwoven fabric for paper diapers by using an elastic yarn beam wound body in which a large number of elastic yarns are wound on a bobbin in a parallel beam state. Place at the yarn feeding position, positively rotate the elastic yarn beam winding body to feed the elastic yarn beam while unwinding, and insert and fix a large number of supplied elastic yarns between the nonwoven fabrics It is characterized by.

The elastic yarn beam roll-up body for producing a disposable diaper stretch nonwoven fabric according to the present invention is an elastic yarn beam roll-up body in which a large number of elastic yarns are rolled up on a bobbin in a parallel beam state. It is characterized by satisfying the condition to be satisfied.
1 <L / (E × D) <7
(Where L = yarn length of elastic yarn (m), E = number of yarns wound up, D = fineness of elastic yarns wound up (dtex))

  This elastic yarn beam winding body for producing a stretchable nonwoven fabric has an elastic yarn beam wound up on a bobbin in the vicinity of the yarn feeding start end located at the outermost winding layer and at the yarn feeding end located at the innermost winding layer. In the vicinity of the portion, it is preferable that the positions of the elastic yarn beam are aligned and regulated by the tape-like material over the entire width of the elastic yarn beam.

  Furthermore, this elastic yarn beam roll-up body for producing a stretchable nonwoven fabric is arranged at the elastic yarn feeding position in the manufacturing process of the stretchable nonwoven fabric for paper diapers, and the elastic yarn beam roll-up body is actively rotated to unwind the elastic yarn beam. In the method of manufacturing a stretchable nonwoven fabric for paper diapers by inserting and fixing a large number of elastic yarns supplied between the nonwoven fabrics, the source of the elastic yarns is wound up by the beam being fed When switching from the body A to the standby beam winding body B, the yarn feeding end of the elastic yarn beam of the beam winding body A and the yarn feeding start end of the elastic yarn beam of the beam winding body B It is preferable to produce a stretchable nonwoven fabric for paper diapers by joining together in the vicinity of the position of the tape-like material attached in the vicinity, and then transferring the yarn from the beam winding body A to the beam winding body B A.

  If the elastic yarn is supplied according to the method of the present invention, the functionality and aesthetics required for the disposable diaper product can be enhanced without substantially deteriorating the productivity at the time of manufacturing the disposable diaper. That is, it is possible to improve the functionality and aesthetics of stretchable nonwoven fabric for paper diapers and paper diapers with easy means that are not disadvantageous in terms of cost, and it is also possible to produce paper diapers with excellent fit when worn. It becomes.

  Hereinafter, the present invention will be described in detail.

  Examples of the elastic yarn used in the present invention include polyurethane-based elastic yarn, polyether-ester-based elastic yarn, polyamide elastic yarn, etc., or thread-like so-called rubber yarn made of natural rubber, synthetic rubber, semi-synthetic rubber, or the like Examples include elastic yarns obtained by combining or mixing with other organic synthetic resins mainly composed of, and those having a rubber-like elasticity are preferable.

The elastic yarn may be either a monofilament or a multifilament. The elastic yarn may be used as a raw yarn as spun, or may be used as a non-elastic yarn or a processed yarn covered with an elastic yarn.
The elastic yarn used in the present invention is particularly preferably a polyurethane elastic yarn.

  Preferred polyurethane-based elastic yarns include a long-chain diol such as a copolyester diol as a soft segment, a diisocyanate such as diphenylmethane-4,4 diisocyanate as a hard segment, and a chain extender such as a bifunctional hydrogen compound. Polyester polyurethane elastic yarn, or polyether based polytetramethylene ether glycol as soft segment, diphenylmethane-4,4 diisocyanate as hard segment, and chain extender such as low molecular weight bifunctional hydrogen compound as main constituents A polyurethane elastic yarn is exemplified.

  Examples of the polyether ester elastic yarn include an elastic yarn having polytetramethylene ether glycol as a soft segment and polybutyl terephthalate as a main component as a hard segment.

  The polyurethane polymer segment used in the polyurethane elastic yarn that can be used in the present invention is composed of a soft segment (a) such as a long-chain polyether segment, a polyester segment or a polyether ester segment, an isocyanate and a chain extender. And a hard segment (b) which is a relatively short chain segment obtained by reaction with a diamine or diol.

  As the soft segment (a) of such a polyurethane-based polymer, 1) a polymer or copolymer obtained from tetramethylene glycol, 3-methyl-1,5-pentanediol, tetrahydrofuran, 3-methyltetrahydrofuran, etc. Ether segment, 2) polyester segment obtained from diols such as ethylene glycol, tetramethylene glycol, 2,2-dimethyl-1,3-propanediol and dibasic acids such as adipic acid and succinic acid, and 3) poly- It is preferable to use a polyetherester segment obtained from (pentane-1,5-carbonate) diol, poly- (hexane-1,6-carbonate) diol, etc., among which the resistance during elongation is reduced, a guide, Reduce the resistance force by needles etc. during knitting From the standpoint of preventing yarn breakage, it is more preferable to use a copolyether polyol of tetrahydrofuran and 3-alkyltetrahydrofuran. In particular, those using a copolyether polyol having a high degree of polymerization are preferred from the viewpoint of obtaining excellent stretch properties.

  The polyurethane polymer is obtained by subjecting a prepolymer product obtained by polyaddition reaction of a hydroxyl-terminated soft segment precursor with an organic diisocyanate (capping reaction) to chain extension with an amine chain extender or a diol chain extender. Can do.

  Examples of the organic diisocyanate used in the production process of the polyurethane polymer include bis- (p-isocyanatophenyl) -methane (hereinafter abbreviated as MDI), tolylene diisocyanate (hereinafter abbreviated as TDI), bis- (4 -Isocyanatocyclohexyl) -methane (hereinafter abbreviated as PICM), hexamethylene diisocyanate, 3,3,5-trimethyl-5-methylenecyclohexyl diisocyanate and the like can be used, and MDI is particularly preferable.

  As the chain extender, an amine chain extender is preferably used. For example, diamines such as ethylenediamine, 1,3-cyclohexanediamine, and 1,4-cyclohexanediamine are preferably used to form polyurethane urea.

  The amine chain extender is not limited to only one kind of diamine, and may be composed of plural kinds of amines. A chain terminator can be included in the reaction mixture to help control the final molecular weight of the polyurethaneurea. Usually, a monofunctional compound having active hydrogen as a chain terminator, such as diethylamine, can be used.

  Further, the chain extender is not limited to the above amine, and may be a diol. For example, ethylene glycol, 1,3-propanediol, 4-butanediol, neopentyl glycol, 1,2-propylene glycol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,4-bis (β -Hydroxyethoxy) benzene, bis (β-hydroxyethyl) terephthalate, paraxylylene diol, and the like can be used. The diol chain extender is not limited to only one type of diol, and may be composed of a plurality of types of diols. Moreover, you may use together with the compound containing one hydroxyl group which reacts with an isocyanate group.

  As a method for producing such a polyurethane polymer, various methods such as a melt polymerization method and a solution polymerization method can be employed. The polymerization formulation is not particularly limited. For example, a method of synthesizing polyurethane or polyurethane urea by simultaneously reacting polyol, diisocyanate, and chain extender composed of diol or diamine can be employed. Any method may be used.

  Moreover, a normal stabilizer etc. can also be mix | blended in the range which does not impair the effect of this invention.

  N, N-dimethylacetamide (hereinafter abbreviated as DMAc), dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone and the like can be used as a solvent when the polyurethane polymer is used as a solution. Is the most commonly used solvent.

  The solution concentration of the polyurethane polymer when used as a spinning solution is not particularly limited, but is usually preferably 30% to 40% (based on the total weight of the solution), and particularly 35% to 38% is a dry spinning method. It is preferable in the case of.

  In the present invention, a method for producing a polyurethane elastic yarn by spinning a polyurethane polymer is not particularly limited. For example, in the case of a polyurethane elastic yarn using a diol as a chain extender, a melt spinning method, It is preferable to employ a dry spinning method or a wet spinning method. In the case of polyurethane urea elastic yarn using diamine as a chain extender, it is usually preferable to employ a dry spinning method.

  When spinning, if necessary, some of the methyl groups of dimethylsilicone and dimethylsilicone may be reduced to reduce friction between the yarn and the guide of the spinning machine, or to prevent electrostatic charging. An oil agent such as silicone oil such as modified silicone substituted with an alkyl group, phenyl group, amino group or the like, or mineral oil may be imparted to the yarn. The cross-sectional shape of the obtained elastic yarn may be circular or flat.

  The fineness of the elastic yarn is preferably 22 dtex or more and 470 dtex or less, but is not limited thereto.

  In addition, as elastic yarn for paper diapers, there is an oilless yarn type that is substantially free of oil, or a small amount of oil that does not hinder the adhesive function of the adhesive used for fixing to the nonwoven fabric. Those attached are preferred. That is, in the case of elastic yarn with oil agent attached, select and use conditions that do not cause problems in adhesion when fixing and fixing with nonwoven fabric with hot melt adhesive etc. in the manufacturing process of elastic nonwoven fabric for disposable diapers Can do.

  Further, the elastic yarn beam winding body used in the present invention has a beam shape in which a large number of the above-described elastic yarns are arranged in parallel, and is wound on the bobbin in this beam state. Here, an array band in which a large number of elastic yarns are arranged in parallel and aligned is hereinafter referred to as a beam.

  The bobbin for hoisting the beam is a cylindrical one commonly used for hoisting fibers and yarns, and has a flange (3) at both ends to prevent the beam from collapsing. For example, a hooked bobbin (2) as shown in FIG. 2 can be used. As the material, general steel, special steel, stainless steel, aluminum, plastic, wood and the like can be used. The dimensions of the bobbin shape, heel diameter (flange diameter), inner width (winding width), outer width, body diameter, etc. are appropriately determined according to the space around the elastic yarn supply position of the paper diaper manufacturing apparatus and the elastic yarn supply design of the paper diaper. You can design freely. For example, the winding width (W) of the bobbin may be determined according to the number (E) of elastic yarns constituting the beam and the fineness of the elastic yarn, but the lateral width per elastic yarn is 0.5 to 7 It may be set to about 5 mm / piece. The winding width (W) when the number (E) of elastic yarns is 30 to 120 is generally about 10 to 50 cm. Further, a bobbin having a thin winding width (reel-shaped bobbin) such as a reel of a movie film may be connected in the axial direction, and the winding width (W) of the reel-shaped bobbin in that case is 0.5-7. What is necessary is just about 5 cm. The cylinder diameter (R) of the bobbin may be about 5 to 20 cm. Further, the heel diameter (F) may be about 30 to 170 cm.

  FIG. 3 schematically shows an example of the elastic yarn beam winding body (1) according to the present invention, and a beam of 40 elastic yarns (Y) is wound on the hooked bobbin shown in FIG. The case is illustrated.

  The elastic yarn beam roll-up body (1) for producing a disposable diaper stretchable nonwoven fabric according to the present invention is an elastic yarn beam roll-up body in which a large number of elastic yarns are rolled up on a bobbin in a parallel beam state. The condition that satisfies is satisfied.

1 <L / (E × D) <7
Here, L is the yarn length (m) of the wound elastic yarn. E is the number of wound elastic yarns, that is, the number of elastic yarns constituting the beam. D is the fineness (dtex) of the wound elastic yarn.

  The number of elastic yarns constituting the beam (E) may be determined according to the elastic nonwoven fabric production conditions such as the width of the elastic nonwoven fabric and the density of the elastic yarn inserted therein, but in general, What is necessary is just to be about 30-200 pieces. Generally, the elastic yarn length (L) may be about 20,000 to 100,000 m.

  When the value of [L / (E × D)] in the beam winding body (1) is 1 or less, the yarn length is short, the yarn feeding transition frequency of the beam winding body is increased, and the productivity of the disposable diaper is deteriorated. On the contrary, if the value of [L / (E × D)] is 7 or more, the yarn length is too long and the weight of the beam winding body becomes heavy, which causes problems in terms of yarn feeding stability and structural strength. Yes, not preferred.

  The elastic yarn beam winding body (1) in the present invention is fixed so that the mutual positional relationship of the elastic yarns in the beam is not disturbed when the beam ends are connected when switching the beam winding body of the beam supply source. For this purpose, it is preferable to attach a tape-like material over the entire width of the beam. This tape-like product is a narrow one in which an adhesive or the like that can adhere to the surface of the elastic yarn exists on the surface, for example, made of imitation paper, fabric, film, aluminum, “Teflon (registered trademark)” An adhesive tape in which an adhesive layer is provided on a tape base material such as a narrow adhesive sheet obtained by cutting an adhesive sheet into a narrow width, or the like can be used. What is necessary is just to select suitably about the material and shape. The tape width may be about 2 to 10 cm, for example.

  The tape-like material for preventing disturbance of the mutual positional relationship of the elastic yarn in the beam is attached in the vicinity of the yarn feeding start end located in the outermost winding layer, and the yarn feeding end located in the innermost winding layer It is preferable to make it adhere in the vicinity of the part.

  Thus, the elastic yarn beam winding body (1) having the tape-like material attached in the vicinity of the yarn feeding start end portion and in the vicinity of the yarn feeding end end portion is placed at the elastic yarn feeding position in the manufacturing process of the elastic nonwoven fabric for disposable diapers. The elastic yarn beam winding body (1) is actively rotated to feed the yarn while unwinding the elastic yarn beam (4), and a large number of supplied elastic yarns are inserted and fixed between the nonwoven fabrics. In the method for producing a stretchable nonwoven fabric for paper diapers, when the source of elastic yarn is switched from the beam winding body A that is being fed to the beam winding body B that is waiting, as shown in FIGS. Performed in the procedure.

  Immediately before switching the supply source of the elastic yarn, as shown in FIG. 4, the elastic yarn beam wound up on the beam winding body A being supplied is almost empty, and is attached near the end of the yarn supply. A tape-like product (5) appears. Further, a portion of the tape-like material (6) attached in the vicinity of the yarn feeding start end portion of the elastic yarn beam is taken out from the beam winding body B in standby. Next, as shown in FIG. 5, the attached end of the tape-like object (6) is pulled out from the standby beam winding body B, and the feeding end of the attached tape-like object (6) and the beam winding body A during feeding is fed. At the end of the yarn, the end to which the tape-like material (5) is attached is joined by attaching another adhesive tape (7). Subsequently, as shown in FIG. 6, the portion joined by the tape is temporarily removed from the yarn guide guide reed (8) so as not to be caught by the yarn guide guide reed (8), and is passed through the tape joined portion. . After passing, as shown in FIG. 7, each of the beam winding bodies is moved downward, and the beam supplied from the beam winding body B ′ that has started feeding passes through the yarn path guide oscillator (8). Lower the yarn path. Next, as shown in FIG. 8, the beam winding bobbin A ′ that has finished supplying yarn is removed, and the beam winding body B ′ that has started supplying yarn is moved to a fixed position during beam supply.

  By switching the beam supply source in such a procedure, the beam switching operation can be performed quickly without disturbing the alignment state of a large number of elastic yarns in the beam.

Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to these examples.
In addition, evaluation in an Example and a comparative example was based on the following method.

[Appearance of disposable diapers]
Whether or not the elastic yarn inserted into the gathered portion of the paper diaper was conspicuous from the top of the nonwoven fabric was evaluated by sensory evaluation by 10 observers to observe with the naked eye. The judgment results are displayed in the following categories.

◎: Eight or more people felt inconspicuous.
○: Fewer than 8 and 6 or more felt inconspicuous.
Δ: Fewer than 6 and 4 or more felt inconspicuous.
×: Fewer than 4 people felt inconspicuous.

[Dispersion of tightening force of disposable diapers]
Whether the elastic yarn inserted into the gathered part of the paper diaper feels difficult to be inserted into the human skin from above the nonwoven fabric was evaluated by sensory evaluation in which 10 judges were pressed against the skin and observed. The judgment results are displayed in the following categories.

A: More than 8 people felt it was difficult to bite in.
○: Fewer than 8 and 6 or more felt that biting was difficult.
Δ: Fewer than 6 and 4 or more felt that biting was difficult.
×: Fewer than 4 people felt it was difficult to bite.

[Production of disposable diapers]
The time required for continuous operation until the replacement of the elastic yarn is defined as (T1), and the time required for replacement with a new elastic yarn after continuous operation is defined as (T2). T3) was determined by the following formula.

T3 = [{24− (24 ÷ T1) × T2} × 7] / 168 × 100
Based on the value of this operating rate (T3), it was determined and displayed in the following categories.
A: When T3 is 96% or more.
○: When T3 is less than 96% and 94% or more.
Δ: T3 is less than 94% and 92% or more.
X: When T3 is less than 92%.

[Example 1]
Elastic yarn used: “LYCRA” (registered trademark) T-127 manufactured by Operontex Co., Ltd.
Fineness (D) of the elastic yarn: 235 dtex
Number of elastic yarns constituting elastic yarn beam (E): 40 yarn length of elastic yarn wound on bobbin as elastic yarn beam (L): 20,000 m
Bobbins used: Aluminum bobbed bobbins (cylinder outer diameter 20 cmφ, winding width 22.5 cm, rod outer diameter 38.0 cmφ)
Tape used: Cloth adhesive tape (width 2.5 cm, length 24.5 cm)

  40 elastic yarn wound bodies are arranged on a feed roller and unwound and supplied at the same speed to form a beam state in which 40 elastic yarns are arranged in parallel within a width of 22.5 cm, and are wound on the bobbin. An elastic yarn beam winding body in which a yarn length (L) of 20,000 m of elastic yarn was wound was produced. In addition, before winding on a bobbin, the cloth adhesive tape was affixed over the beam width in the position of 200 cm from the winding start end of the elastic yarn beam. Furthermore, a cloth adhesive tape was pasted over the beam width at a position 300 cm from the end of winding.

  The obtained elastic yarn beam winding body is arranged at the elastic yarn feeding position of the paper diaper manufacturing apparatus, and the speed is adjusted so that the speed of the elastic yarn unwound from the beam winding body and supplied is 50 m / min. While actively rotating the beam hoist to unwind the elastic yarn, and then adjusting the draft rate of the elastic yarn to double with a draft roller rotating at a surface speed of 100 m / min. The elastic yarn is inserted between the nonwoven fabrics at a distance of 1.5 mm, and the elastic yarn and the nonwoven fabric are fixed with a hot melt adhesive to produce a stretchable nonwoven fabric for paper diapers. Using this stretchable nonwoven fabric, ordinary paper diapers Manufactured.

The paper diaper thus obtained had a very excellent appearance because the elastic yarn was hardly noticeable from the appearance because thin elastic yarn was used. Also, the degree of dispersion of gather tightening force was at an excellent level.
Moreover, regarding the productivity of disposable diapers, it was possible to sufficiently shorten the time required for switching the elastic yarns and to sufficiently shorten the stop time, and an excellent productivity improvement effect was recognized.

[Example 2]
Elastic yarn used: “LYCRA” (registered trademark) T-127 manufactured by Operontex Co., Ltd.
Fineness (D) of the elastic yarn: 117 dtex
Number of elastic yarns constituting the elastic yarn beam (E): 80 yarn length of elastic yarn wound on the bobbin as an elastic yarn beam (L): 20,000 m
Bobbins used: Aluminum bobbed bobbins (cylinder outer diameter 20 cmφ, winding width 22.5 cm, rod outer diameter 38.0 cmφ)
Tape used: Cloth adhesive tape (width 2.5 cm, length 24.5 cm)

  80 of the elastic yarn wound bodies are arranged on a feed roller and unwound and supplied at the same speed to form a beam state in which 80 elastic yarns are arranged in parallel within a width of 22.5 cm, and are wound on the bobbin. An elastic yarn beam winding body in which a yarn length (L) of 20,000 m of elastic yarn was wound was produced. As in Example 1, when winding on the bobbin, a cloth adhesive tape covering the beam width was applied in the vicinity of the winding start end of the elastic yarn beam, and a cloth adhesive tape covering the beam width was applied in the vicinity of the winding end end. I pasted it.

  The obtained elastic yarn beam winding body was placed at the elastic yarn feeding position of the paper diaper manufacturing apparatus, and the distance between the elastic yarns when inserted between the nonwoven fabrics was changed to 0.75 mm, in the same manner as in Example 1. Then, a stretchable nonwoven fabric for paper diapers was prepared, and then a normal paper diaper was manufactured.

The paper diaper obtained in this way had very thin elastic yarns, so that the elastic yarns were hardly noticeable from the appearance, and the appearance was very excellent. In addition, the degree of dispersion of the gathering tightening force was very excellent.
Moreover, regarding the productivity of disposable diapers, it was possible to sufficiently shorten the time required for switching the elastic yarns and to sufficiently shorten the stop time, and an excellent productivity improvement effect was recognized.

[Example 3]
Elastic yarn used: “LYCRA” (registered trademark) T-127 manufactured by Operontex Co., Ltd.
Fineness (D) of the elastic yarn: 235 dtex
Number of elastic yarns constituting elastic yarn beam (E): 80 yarn length of elastic yarn wound on bobbin as elastic yarn beam (L): 10,000 m
Bobbins used: Aluminum bobbed bobbins (cylinder outer diameter 20 cmφ, winding width 22.5 cm, rod outer diameter 38.0 cmφ)
Tape used: Cloth adhesive tape (width 2.5 cm, length 24.5 cm)

  80 of the elastic yarn wound bodies are arranged on a feed roller and unwound and supplied at the same speed to form a beam state in which 80 elastic yarns are arranged in parallel within a width of 22.5 cm, and are wound on the bobbin. An elastic yarn beam winding body in which a yarn length (L) of 10,000 m of elastic yarn was wound was produced. As in Example 1, when winding on the bobbin, a cloth adhesive tape covering the beam width was applied in the vicinity of the winding start end of the elastic yarn beam, and a cloth adhesive tape covering the beam width was applied in the vicinity of the winding end end. I pasted it.

  The obtained elastic yarn beam winding body was placed at the elastic yarn feeding position of the paper diaper manufacturing apparatus, and the distance between the elastic yarns when inserted between the nonwoven fabrics was changed to 0.75 mm, in the same manner as in Example 1. Then, a stretchable nonwoven fabric for paper diapers was prepared, and then a normal paper diaper was manufactured.

The paper diaper obtained in this way had a very excellent appearance because the elastic yarn was hardly noticeable from the appearance because thin elastic yarn was used. Also, the degree of dispersion of gather tightening force was at an excellent level.
Further, regarding the productivity of the disposable diaper, the time required for switching the elastic yarn was slightly longer than that in Example 1, but was within a satisfactory level.

[Example 4]
Elastic yarn used: “LYCRA” (registered trademark) T-127 manufactured by Operontex Co., Ltd.
Fineness (D) of the elastic yarn: 117 dtex
Number of elastic yarns constituting elastic yarn beam (E): 40 yarn length of elastic yarn wound on bobbin as elastic yarn beam (L): 40,000 m
Bobbins used: Aluminum bobbed bobbins (cylinder outer diameter 20 cmφ, winding width 22.5 cm, rod outer diameter 38.0 cmφ)
Tape used: Cloth adhesive tape (width 2.5 cm, length 24.5 cm)

  40 elastic yarn wound bodies are arranged on a feed roller and unwound and supplied at the same speed to form a beam state in which 40 elastic yarns are arranged in parallel within a width of 22.5 cm, and are wound on the bobbin. An elastic yarn beam winding body in which the yarn length (L) of the elastic yarn was wound up to 40,000 m was produced. As in Example 1, when winding on the bobbin, a cloth adhesive tape covering the beam width was applied in the vicinity of the winding start end of the elastic yarn beam, and a cloth adhesive tape covering the beam width was applied in the vicinity of the winding end end. I pasted it.

  The obtained elastic yarn beam roll-up body was placed at the elastic yarn feeding position of the paper diaper manufacturing apparatus, and a stretchable nonwoven fabric for paper diapers was produced in the same manner as in Example 1, followed by manufacturing a normal paper diaper.

The paper diaper obtained in this way had a very excellent appearance because the elastic yarn was hardly noticeable from the appearance because thin elastic yarn was used. Also, the degree of dispersion of gather tightening force was at an excellent level.
Moreover, regarding the productivity of disposable diapers, the time required for switching the elastic yarn can be greatly shortened, and the stopping time can be greatly shortened, which is a very excellent productivity improvement effect.

[Comparative Example 1]
Elastic yarn used: “LYCRA” (registered trademark) T-127 manufactured by Operontex Co., Ltd.
Fineness (D) of the elastic yarn: 470 dtex
Number of elastic bobbin used for elastic yarn supply (number of elastic yarns supplied): Length of elastic yarn wound around 10 bobbin (L): 95,800 m
Winding amount of used winding body: 4.5kg

  As shown in FIG. 9, ten elastic yarn wound bodies are arranged in series at the elastic yarn feeding position (position on the feeding roller) of the paper diaper manufacturing apparatus, and the elastic yarn supply speed is 50 m / min. The elastic yarn is positively unwound while adjusting the rotation speed of the feed roller so that the speed becomes the speed, and then the draft magnification of the elastic yarn is doubled with a draft roller that rotates at a surface speed of 100 m / min. The elastic yarn and the nonwoven fabric are fixed with a hot melt adhesive, and a stretchable nonwoven fabric for paper diapers is produced by using the stretchable nonwoven fabric. The usual paper diapers were manufactured.

  The paper diaper thus obtained was not satisfactory in appearance even when the elastic yarn was seen with the naked eye, and further, the degree of dispersion of gather tightening force was not satisfactory.

  Table 1 summarizes the conditions for the examples and comparative examples and the evaluation of the resulting disposable diapers.

  Each of the disposable diapers manufactured in Examples 1 to 4 was at a level that could satisfy both the appearance and the degree of dispersion of the tightening force of the gathered portion, and there was no problem in terms of productivity. On the other hand, Comparative Example 1 was excellent in terms of productivity of the disposable diaper, but was not satisfactory in terms of the appearance of the manufactured disposable diaper and the degree of dispersion of the tightening force of the gathered portion.

  The yarn supplying method of the elastic yarn of the present invention can be applied to a stretchable nonwoven fabric manufacturing process in a paper diaper manufacturing process, and when manufacturing a paper diaper excellent in functionality such as appearance aesthetics and fit. Is preferred. Moreover, the yarn feeding method of the elastic yarn of the present invention can also be used in the step of inserting the elastic yarn into a nonwoven fabric product such as a sanitary napkin.

It is a figure (top view, side view) which shows typically the state which supplies many elastic yarns from an elastic yarn beam winding body by this invention method. It is a figure which shows an example of the bobbin used in the elastic yarn beam winding body of this invention. It is a figure which shows an example of the elastic yarn beam winding body of this invention. In the present invention method, it is a diagram (top view, side view) schematically showing a state immediately before starting to switch from a beam winding body during yarn feeding to a beam winding body during standby. In this invention method, it is a figure (top view, side view) which shows typically the state which connected the beam terminal part during yarn feeding, and the beam start end part in standby. In this invention method, it is a figure (top view, side view) which shows typically the state which supplies the part which joined the edge part of the beam. FIG. 7 is a diagram (top view, side view) schematically showing a state following FIG. 6. FIG. 8 is a diagram (top view, side view) schematically showing a state following FIG. 7. It is a top view which shows typically the state which unwinds and supplies an elastic thread | yarn from several elastic bobbin thread bodies by the conventional method.

Explanation of symbols

1: Elastic thread beam winding body 2: Bobbin 3: Bobbin collar 4: Elastic thread beam 5, 6: Tape-like material (adhesive tape)
7: Bonding adhesive tape 8: Yarn guide guide 11: Feeding roller 12: Elastic bobbin 13: Guide A: Beam hoist during feeding B: Beam hoist during standby Y: Elastic thread W: Bobbin Winding width R: Bobbin cylinder diameter F: Bobbin diameter

Claims (4)

The elastic yarn beam winding body, which is wound on a bobbin in a beam state in which a large number of elastic yarns are arranged in parallel, is placed at the elastic yarn feeding position in the manufacturing process of the elastic nonwoven fabric for disposable diapers, and the elastic yarn beam winding body is positively A method for producing a stretchable nonwoven fabric for paper diapers, wherein the elastic yarn beam is unwound and fed while unwinding, and a plurality of fed elastic yarns are inserted and fixed between the nonwoven fabrics. An elastic yarn beam-rolled body wound on a bobbin in a beam state in which a large number of elastic yarns are arranged in parallel, and satisfying the following condition: Elastic yarn for producing disposable diaper stretchable nonwoven fabric Beam hoisting body.
1 <L / (E × D) <7
(However, L = yarn length of elastic yarn wound up (m), E = number of yarns of elastic yarn wound up, D = fineness of elastic yarn wound up (dtex)) The elastic yarn beam wound up on the bobbin extends over the entire width of the elastic yarn beam in the vicinity of the yarn feeding start end located in the winding outermost layer and in the vicinity of the yarn feeding end end located in the winding innermost layer, respectively. The elastic yarn beam roll-up body for producing a disposable diaper stretchable nonwoven fabric according to claim 2, wherein the position is regulated by a tape-like material. 4. The elastic yarn beam roll-up body for producing a stretchable nonwoven fabric according to claim 3 is disposed at an elastic yarn feeding position in the production process of the stretchable nonwoven fabric for paper diapers, and the elastic yarn beam roll-up body is actively rotated to thereby produce an elastic yarn beam. In the method of manufacturing a stretchable nonwoven fabric for paper diapers by inserting and fixing a large number of elastic yarns fed between the nonwoven fabrics while unwinding the yarn, When the beam winding body A is switched from the beam winding body A to the standby beam winding body B, the yarn feeding end end portion of the elastic yarn beam of the beam winding body A and the yarn feeding start end portion of the elastic yarn beam of the beam winding body B are A method for producing a stretchable nonwoven fabric for a paper diaper, characterized by joining the vicinity of a position of a tape-like object attached in the vicinity of an end, and then transferring yarn from the beam winding body A to the beam winding body B .

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