Performance and production technology result diligent in one's studies thereof as to the bondedfibre fabric that contains melt-adhesive composite fibers it is found that the invention that proposes has below solved the defective that exists in the prior art:
The invention provides and contain first component that comprises crystalline polypropylene and mainly comprise poly second component, two components are with the melt-adhesive composite fibers of arranged side by side or eccentric sheath-core relation setting, wherein the second component continued presence in the fibre length direction to the surface of small part fiber, has the three-dimensional crimp of 4-16 inch, filament denier is 1.0-2.0, and apparent length is 20-40mm.
Composite fibre of the present invention can be through the following steps enforcement and produce:
Utilize the polymers compositions spinning step of the spinnerets that spins arranged side by side or eccentric sheath-core type composite fiber,
Be higher than 90 ℃, be lower than 130 ℃ temperature, the stretching step of the undrawn yarn that so obtains to stretch under the 0.6-0.85 times of stretch rate of maximum tension ratio,
Cool off under the temperature that this drawn yarn to one is lower than preheat temperature and carry out the curling treatment step of silk, and
Be higher than 80 ℃, but be lower than the HEAT SETTING step of the silk that carries out under 120 ℃ the temperature.
Further, the present invention will provide the above above-mentioned melt-adhesive composite fibers of a kind of 50%wt of containing or the part fused fabric of the fiber that obtains according to above-mentioned processes.In fabric of the present invention, the mutual crosspoint of composite fibre is interconnective by the fusion of second component in the composite fibre.
Further, the present invention will provide a kind of amenities used surfacing, and thickness is greater than 1mm, and contains the fabric of above-mentioned part clinkering.
Be often referred to the propylene that contains polymerization as the crystalline polypropylene of composite fibre the first component of the present invention as a kind of crystalline polymer of key component, not only comprise Noblen, and comprise propylene and ethene, butene-1, or the copolymer of 4-methylpentene.
Main polyethylene as second component is often referred to the ethene that contains polymerization as the polymer of key component in composite fibre of the present invention, such as in or low-pressure polyethylene and polyethylene from high pressure process, it not only comprises Alathon, and comprise ethene and propylene, the copolymer of butene-1 or vinylacetate (EVA). Poly fusing point is preferably lower than as 20 ℃ of the fusing points of the crystalline polypropylene of the first component or more.
Above-mentioned crystalline polypropylene and polyethylene can contain the various additives that are generally used for polyolefine fiber being unlikely to not reach in this scope of the object of the invention, such as stabilizing agent, and filler and pigment.
Melt-adhesive composite fibers among the present invention is to form by a spinneret extruding spinning that spins parallel type or eccentric sheath-core type composite fiber. Second component must continued presence at least part of fiber surface of fibre length direction, and best as far as possible wide the topped fiber surface of second component. Because it is to utilize the difference of two component elastic shrinkage to produce curling that heat is melted adhesive composite fibers, eccentric sheath-cored structure shown in the figure one preferably is in the situation that this composite fibre has sheath-core pattern structure, and the 5-15% (based on the diameter of sheath-core composite fibre) at sheath component center is preferably departed from the center of core component.
Composite fibre of the present invention can utilize the conventional method of spinning parallel composite fiber or eccentric sheath-core type composite fiber and obtain, wherein second component is used as the sheath component, ratio to two components in the composite fibre is not particularly limited, but second component is preferably 40-70%wt.
Melt-adhesive composite fibers of the present invention has three-dimensional crimp. Composite fibre had better not produce curling when heat treatment prepares adhesive-bonded fabric, and in other words, composite fibre of the present invention had better not produce rear curling. When heat treatment of fiber, basically do not produce afterwards when curling, produce the curling filament contraction that causes and when heat treatment prepares adhesive-bonded fabric, can avoid.
The crispation number of melt-adhesive composite fibers of the present invention is generally the 4-16/ inch, and is preferably the 6-14/ inch. When crispation number is less than 4/ inch, it causes the winding of fiber on the carded machine barrel. When crispation number surpasses 16/ inch, the hole variation, and the silk knot forms when causing adhesive-bonded fabric to prepare.
Melt-adhesive composite fibers of the present invention must have filament denier 1.0-2.0. When the dawn number is lower than 1.0, the curling formation that becomes too thin and cause the silk knot. When the dawn number surpasses 2.0, there is the volume recovery downward trend of a kind of feel hardening and the rear adhesive-bonded fabric of compression.
The apparent shearing length of melt-adhesive composite fibers of the present invention is generally 20-40mm, and is preferably 25-35mm. When it was lower than 20mm, the transmission performance of fiber on carding machine was low, and it becomes the reason of fiber curling round the roll problem. When it surpassed 40mm, the entanglement of fiber was apparent and becomes the reason that the silk knot forms.
The apparent shearing length of melt-adhesive composite fibers of the present invention is preferably 50-70% to the ratio of shearing length.When ratio was lower than 50%, the transmission performance of fiber on carding machine was low, and the fiber curling round the roll causes the formation of silk knot.When ratio surpassed 70%, it is very strong that the entanglement of fiber becomes, and cause the winding of fiber on the feeding roller, and the carded step itself becomes impossible.
The production method of melt-adhesive composite fibers of the present invention comprises:
By a spinning side by side or the polymers compositions spinning step of the spinnerets of sheath-core type composite fiber,
Be higher than 90 ℃, but be lower than under 130 ℃ the temperature, the undrawn yarn that so obtains is being carried out stretching step with the draw ratio of 0.6-0.85 times of maximum tension ratio,
Cooling drawn yarn to is lower than the temperature of preheat temperature and carries out the curling treatment step of silk, and
Be higher than 80 ℃, but be lower than the HEAT SETTING step of carrying out fiber under 120 ℃ the temperature.
In the spinning step, comprise first component of a crystalline polypropylene and mainly comprise poly second component by a spinning side by side or the spinnerets of sheath-core type composite fiber extrude make long filament so that the second component continued presence at least a portion fiber surface.
In stretching step, the undrawn yarn of extruding is preheated to a draft temperature.When draft temperature was lower than 90 ℃, curling became too thin.When draft temperature surpassed 130 ℃, mutual obvious clinkering took place and unfavorable in the composite fibre polyethylene.
When stretch rate was lower than 0.6 times of maximum tension ratio, the difference of two component elastic recoverys diminished and therefore curls and can not produce.When draw ratio surpassed 0.85 times of maximum tension ratio, the difference of two component elastic recoverys became too big and crimped loops diminishes.Its consequence not only crispation number becomes many, and the apparent shearing length of fiber becomes too short and unfavorable.The maximum tension ratio is meant when stretch rate rises gradually, the stretch rate when strand begins lousiness to occur.
In curl handling, drawn yarn is cooled off being lower than under the temperature of draft temperature, and tow is got at tension force condition last volume with the winding wheel of a deflector roll such as nip rolls, and the loose generation of tow subsequently is curling.Surpassing when carrying out under the temperature of draft temperature when curl handling, curling generation is insufficient.
In the HEAT SETTING step, produce the tow that curls in curl handling and be higher than 80 ℃, be lower than under 120 ℃ the temperature and carried out HEAT SETTING 0.5-30 minute.When heat setting temperature is lower than 8 ℃, exist in the preparation bondedfibre fabric step and produce the possibility of curling in disadvantageous back.When heat setting temperature is higher than 120 ℃ and since two component elastic recovery difference produce curling stretch and the apparent shearing length of fiber elongated and unfavorable.
Consider that from the viewpoint that bondedfibre fabric processing is easy melt-adhesive composite fibers of the present invention usually is cut into predetermined length and is used as staple fibre.
The fabric of part clinkering of the present invention can contain more than the 50wt%, reaches the above-mentioned melt-adhesive composite fibers until 100wt%.The bondedfibre fabric of part clinkering can utilize conventional carded method, the gas meltblown, or the dry pulp method changes melt-adhesive composite fibers into a bondedfibre fabric and this bondedfibre fabric is heat-treated so that fabric portions clinkering and obtaining.The bondedfibre fabric of part clinkering can contain the following polyester of 50wt%, polyamide, and polypropylene, polyethylene, or other synthetic fiber, natural fabric such as cotton and wool, or regenerated fiber such as artificial silk are as the fiber that is different from melt-adhesive composite fibers.In this step, melt-adhesive composite fibers must be in fabric blending 50wt% or more consumption.When the content of melt-adhesive composite fibers is lower than 50wt%, not only can not get the fabric of high nonwoven intensity, because the fiber part that is cross-linked with each other is less in the fabric, and the high loft and the high volume recovery of fabric can not obtain after the compression of expection.
As the method for part clinkering melt-adhesive composite fibers, add the method for hot air drying machine or air suction type band drier as example by using one.By these methods are used in fabric, mutual clinkering forms fabric to the mutual cross section of composite fibre by the fusion of second component.Fusion bonded temperature is usually above the fusing point of second component, but is lower than the fusing point of first component, is preferably 120-155 ℃.With the drying machine is example, and the clinkering time was longer than 5 seconds usually.
Surfacings such as amenities of the present invention are to utilize the bondedfibre fabric of part clinkering to produce, and common thickness is greater than 1mm.When bulky character greater than 1mm, and particularly the elastic recovery after the compression to be higher than 50% o'clock surfacing be satisfactory.When thickness is lower than 50% less than 1mm and recovery, material can not obtain soft feel.
The thickness of indication is meant material is applied 50gf/cm in this specification
2After the load 24 hours, allow material also under the 2gf/cm2 load, measure thickness and definite one-tenth-value thickness 1/10 (mm) subsequently with the thickness that recovers it at the non-loaded lhr that leaves standstill down.Elastic recovery after the compression is meant that the surfacing that is scaled behind the percentage (%) applies 50kgf/cm
2Thickness of measuring behind the load 24hr and same surfacing are in the non-loaded thickness difference of measuring after with the thickness that recovers it after down making it to leave standstill 1hr.
According to the present invention, can produce and have high volume recovery, good forming characteristic, high strength and the heat that has soft feel are simultaneously melted the compound fibre of self-adhesion, and therefore as surfacings such as amenitiess, particularly, part fused fabric of the present invention can be widely used in sanitary napkin and paper nappy.
Embodiment
With reference to embodiment, the present invention will obtain more specific description.Yet, must understand that these specific embodiments must not limit the present invention.Physical property value among the embodiment is measured by the following method:
Crispation number: the crispation number of melt-adhesive composite fibers is measured according to JIS L1015 (chemical fibre staple fibre method of testing) 7.12.1.
Filament denier: the filament denier of melt-adhesive composite fibers is measured according to JIS L1015 (staple fibre method of testing) 7.5.1-A.
Apparent shearing length: the apparent shearing length of melt-adhesive composite fibers is curlingly to stretch and do not apply extra masterpiece and be used for measuring the length (mm) of fiber under the staple fibre and determining what do not make staple fibre under the no tension force.Obtain the mean value of 30 measurements.
Volume is replied: it is by measuring fabric to be applied 50gf/cm that the volume of the bondedfibre fabric of part clinkering is replied
2The thickness of sample fabric (A) behind the load 24hr makes fabric leave standstill 1hr to recover its volume down non-loaded, at load 2gf/cm
2Under measure fabric thickness (B), and obtain according to following equation volume calculated response rate:
When evaluation result, have 50% fabric and be considered to acceptable, and that other fabric is thought is unacceptable with the upper volume response rate.Acceptable fabric is set at A, and unacceptable fabric is set at C.
Bondedfibre fabric intensity: the intensity of the bondedfibre fabric of part clinkering is measured according to JIS L1085 (test of bondedfibre fabric interlayer cloth).Be that 10cm and draw speed are to measure the wide sample thing of 5cm under the condition of 30 ± 2cm/min by stretching along the intensity (MD) of fabric direction and perpendicular to the intensity (CD) of fabric direction wherein in clamp distance.During evaluation result, have the above fabric of MD intensity 2500g/5cm and think acceptablely, be lower than 2500g/5cm and then think unacceptable; Have the above fabric of CD intensity 500g/5cm and think acceptablely, be lower than 500g/5cm and then think unacceptable.Acceptable fabric is made as A, and unacceptable fabric is made as C.
Silk footing order: the silk footing of the bondedfibre fabric of part clinkering is by counting 1cm
2Silk footing and be scaled number/m on the sample fabric
2And determine.At review as a result the time, have 1 or the bondedfibre fabric that do not have a part clinkering of silk knot and think acceptablely, the silk knot more than 2 is then thought unacceptable.Acceptable fabric is set at A, and unacceptable fabric is set at C.
Feel: the feel of the bondedfibre fabric of part clinkering is carried out sensory test by 5 Quality Inspectors and is determined.When all Quality Inspector's judgement sample fabric sofetenings, fabric is considered to " good "; When the Quality Inspector more than three judges fabric sofetening, fabric is considered to " well "; When the Quality Inspector more than three judges that the sample fabric soft feel is insufficient, fabric is considered to " poor ".Good fabric is set at A, and good fabric is set at B, and the fabric of difference is set at C.
Fabric shrink: the contraction of the no fabric of part clinkering can be 25cm by sample fabric being cut into size
2, under 145 ℃, heat 5min with drying machine down non-loaded, measure along the contraction on three points of fabric direction, by calculating mean value.During evaluation, have the fabric that is lower than 10% contraction and think acceptablely, think unacceptable and have the fabric that shrinks more than 10%.Can accept fabric and be made as A, unacceptable fabric is set at C.
Embodiment 1-4 and comparative example 1-9
Every kind of melt-adhesive composite fibers staple fibre shown in the table 1 is to have 350 holes by one, diameter 0.6mm, the spinnerets that is used to spin sheath-core or eccentric parallel composite fiber extrude polypropylene as first component and polyethylene as second component to form tow, reach drawn tow under the conditions shown in Table 1, and the drawn yarn cutting short-forming fiber is obtained.The fiber physical property that obtains thus is shown in table 1.
The staple fibre of the every kind of melt-adhesive composite fibers that obtains thus utilizes carding machine to make basic weight to be 20-30g/m
2Fabric, and carry out 5 seconds of heat treatment of fabric to obtain the bondedfibre fabric of the mutual clinkering of the mutual cross section of a fiber with an air suction type band drier at 135-140 ℃ predetermined temperature.The characteristic of bondedfibre fabric is shown in table 2.In the embodiment 4 and comparative example 9 of table 2, use among the embodiment 1 and the staple fibre in the comparative example 3.
Table 1
| The melt-adhesive composite fibers physical property |
| | First component | Second component | Composite construction | Compound ratio the first/the second component | Draft temperature (℃) | Chilling temperature (℃) | Heat setting temperature ℃ |
| Embodiment 1 | PP
2)
| PE
3)
| Eccentric sheath-core | 50/50 | 115 | 50 | 100 |
| Comparative example 1 | " | " | Eccentric sheath-core | " | " | " | 130 |
| Comparative example 2 | " | " | Eccentric sheath-core | " | " | " | 100 |
| Comparative example 3 | " | " | Eccentric sheath-core | " | " | " | " |
| Comparative example 4 | " | " | Eccentric sheath-core | " | 110 | 80 | 80 |
| Comparative example 5 | " | " | Eccentric sheath-core | " | " | " | " |
| Comparative example 6 | " | " | Eccentric sheath-core | " | 115 | 50 | 100 |
| Embodiment 2 | " | LL
4)
| Eccentric sheath-core | 40/60 | 95 | 40 | 80 |
| Comparative example 7 | " | " | Eccentric sheath-core | " | " | " | " |
| Embodiment 3 | " | PE3) | Side by side | 50/50 | 110 | 100 | 100 |
| Comparative example 8 | " | " | Side by side | " | " | 60 | 60 |
2) PP: PE crystalline polypropylene 3): LL high density polyethylene (HDPE) 4): linear low density polyethylene
Table 1 (continuing)
| The melt-adhesive composite fibers physical property ' |
| | Actual stretch rate | The maximum tension ratio | The MS ratio
9 | Crispation number/inch | Wrapped configuration | Filament denier | Shearing length mm | Apparent shearing length mm |
| Embodiment 1 | 4.0 | 4.8 | 0.83 | 11.3 | Three-dimensional | 1.5 | 51 | 34 |
| Comparative example 1 | " | " | " | 3.5 | Three-dimensional | " | " | 43 |
| Comparative example 2 | 4.4 | " | 0.92 | 18.2 | Three-dimensional | " | " | 21 |
| Comparative example 3 | 4.0 | " | 0.83 | 12.7 | Machinery 5) | " | " | 29 |
| Comparative example 4 | 3.2 | 3.5 | 0.91 | 16.0 | Three-dimensional | 0.8 | " | 22 " |
| Comparative example 5 | 2.0 | " | 0.57 | 3.1 | Three-dimensional | 1.5 | " | 43 |
| Comparative example 6 | 4.0 | 4.8 | 0.83 | 11.3 | Three-dimensional | " | 64 | 44 |
| Embodiment 2 | " | 5.1 | 0.78 | 13.3 | Three-dimensional | 2.0 | 51 | 28 |
| Comparative example 7 | 3.3 | " | 0.64 | 13.9 | Three-dimensional | 3.0 | " | 25 |
| Embodiment 3 | 3.4 | 3.9 | 0.87 | 6.5 | Three-dimensional | 1.0 | 38 | 26 |
| Comparative example 8 | " | 3.8 | 0.89 | 15.1 | Three-dimensional | " | " | 17 |
1) MS ratio: actual draw ratio ÷ maximal draw ratio 5) machinery: the wrapped configuration of utilizing stuffer box to obtain.
Table 2
| | The bondedfibre fabric physical property of clinkering |
| | Content % | Basic weight g/m
2 | Bulkiness | Strength characteristics |
| Thickness (mm) | Volume recovery (%) | Estimate | MD g/5cm | Estimate |
| Embodiment 1 | 100 | 25 | 2.0 | 61 | A | 2840 | A |
| Comparative example 1 | The fiber of comparative example 1 can not form bondedfibre fabric |
| Comparative example 2 | 100 | 25 | 1.9 | 68 | A | 2520 | A |
| Comparative example 3 | " | " | 0.7 | 38 | C | 3150 | A |
| Comparative example 4 | " | " | 1.7 | 57 | A | 2720 | A |
| Comparative example 5 | The fiber of comparative example 5 can not form bondedfibre fabric |
| Comparative example 6 | 100 | 25 | 1.6 | 60 | A | 2670 | A |
| Embodiment 2 | " | 30 | 2.2 | 53 | A | 3200 | A |
| Comparative example 7 | " | " | 1.4 | 32 | C | 2200 | C |
| Embodiment 3 | " | 20 | 1.3 | 55 | A | 2610 | A |
| Comparative example 8 | " | " | 1.0 | 62 | A | 2550 | A |
| Embodiment 4 | 50
6)
| 25 | 1.3 | 51 | A | 2950 | A |
| Comparative example 9 | 30
7)
| " | 1.0 | 45 | C | 3030 | A |
6) fiber (50%) blending of the fiber of embodiment 1 (50%) and comparative example 3.7) fiber (70%) blending of the fiber of embodiment 1 (30%) and comparative example 3.
Table 2 (continuing)
| | The bondedfibre fabric physical property of clinkering |
| | Strength characteristics | Shaping characteristic | Feel |
| CDg/5cm | Estimate | Naps silk knot is (individual/m
2)
| Estimate | Fabric shrinkage (%) | Estimate |
| Embodiment 1 | 610 | A | 0 | A | 3.1 | A | A |
| Comparative example 1 | (fiber of comparative example 1 can not be split into bondedfibre fabric) |
| Comparative example 2 | 590 | A | 13 | C | 4.7 | A | B |
| Comparative example 3 | 780 | A | 0 | A | 2.9 | A | C |
| Comparative example 4 | 510 | A | 38 | C | 6.3 | A | B |
| Comparative example 5 | (fiber of comparative example 5 can not form bondedfibre fabric) |
| Comparative example 6 | 500 | A | 9 | C | 3.2 | A | B |
| Embodiment 2 | 630 | A | 1 | A | 2.0 | A | A |
| Comparative example 7 | 450 | C | 0 | A | 1.8 | A | C |
| Embodiment 3 | 550 | A | 0 | A | 2.9 | A | A |
| Comparative example 8 | 540 | A | 57 | C | 13.1 | C | B |
| Embodiment 4 | 640 | A | 0 | A | 2.8 | A | A |
| Comparative example 9 | 660 | A | 0 | A | 2.8 | A | B |