CN1106469C

CN1106469C - Cellulose-binding fibres

Info

Publication number: CN1106469C
Application number: CN98805895A
Authority: CN
Inventors: P·H·汉森; A·M·拉尔森
Original assignee: FiberVisions AS
Current assignee: FiberVisions AS
Priority date: 1997-04-08
Filing date: 1998-03-31
Publication date: 2003-04-23
Anticipated expiration: 2018-03-31
Also published as: JP3672324B2; AU6918298A; EP0973966A1; TW436535B; CN1259178A; CA2281802A1; DK0973966T3; DE69808061T2; IL131586A0; DE69808061D1; WO1998045519A1; KR20010005771A; IL131586A; ID24606A; EP0973966B1; KR100403057B1; CA2281802C; JP2001518986A; BR9809749A

Abstract

The invention relates to drylaid nonwoven materials comprising bicomponent fibres comprising a low melting polyolefin component and a high melting polyolefin component, the low melting polyolefin component constituting at least a part of the surface of the fibre and comprising a non-grafted polyolefin component and a grafted polyolefin component, wherein the grafted polyolefin component has been grafted with an unsaturated dicarboxylic acid or an anhydride thereof, e.g. with maleic acid or maleic anhydride. The bicomponent fibres fibres have an excellent bonding affinity for natural fibres such as cellulose pulp fibres and allow the production of airlaid nonwovens with reduced generation of dust during the production process and with improved nonwoven strength properties.

Description

A kind of dry-laying non-woven fabric material and production method thereof and the bicomponent fiber that is used to produce this material

Technical field

The present invention relates to a kind of dry-laying non-woven fabric material that contains the polyolefin bicomponent fiber, it has the remarkable bonding affinity to natural fabric such as cellulose fibre.

Background of invention

Absorbent articles of personal hygiene, as throw-away nappy, except that comprising permeable lining, fluid-tight rear panel and one or more liquid Distribution Layers, also comprise absorbent core, it comprises usually such as the natural fabric of cellulose fluff pulp fibres, based on the synthetic fiber and superabsorbent polymer (SAP) material of for example polyolefin and/or polyester.In this types of absorbent agent core, be generally synthetic fiber such as the bicomponent fiber of polypropylene, polyethylene or polyester/polyethylene, formed the supporting network of this absorbent core by heat bonding each other.In ideal conditions, synthetic fiber should be able to be not only own bonded to each other, and can be bonding with natural fabric and SAP, so that form a kind of solid as far as possible and cored structure with cohesion, and natural fabric wherein and SAP are locked in the suitable position of inside configuration.

Yet, be used for doing the shop goods at present, but exist such as the unsatisfactory shortcoming of the cohesiveness of cellulose fibre as the synthetic fiber of air-laid non-weaving cloth production.This problem is because following former thereby become serious increasingly, that is, natural fabric is compared generally all shorter with synthetic fiber, and for example the length of fluff pulp fibers is no more than 3mm, synthetic fiber then general (although not necessarily) much longer.As a result, in manufacture process, produce mao problem, and it is also unsatisfactory to make the performance of non-weaving cloth, because, most natural fabric is not bonding with any synthetic fiber, or opposite, and the structure of the bonding formation of synthetic fiber oneself of also having no backing is maintained at certain position.

Therefore, the purpose of this invention is to provide a kind of bi-component synthetic fiber, it has improved bonding affinity to the natural fabric such as the cellulose fluff pulp fibres, thereby is particularly suitable for producing the dry-laying non-weaving cloth that contains synthetic fiber-natural fabric mixture.

EP 0465203-B1 discloses a kind of heat-bondable fiber wet method laying net fibre web that comprises bicomponent fiber, this fiber comprises first component that is made of polyester, polyamide or polypropylene and is that linear low density polyethylene (LLDPE) (LLDPE) and the density of 0.88～0.945g/cc is second component that the grafted high density polyethylene (HDPE) of 0.94～0.965g/cc constitutes by density, in this HDPE grafting maleic acid or maleic anhydride so that butanedioic acid or the succinic anhydride group along the HDPE polymer to be provided.

EP 0421734-B1 discloses by 2 kinds of fusing points and has differed the thermal bondable bicomponent fiber that at least 20 ℃ different polyolefin constitute, and wherein low melting point polyolefin comprises the monoglyceride that mixes in the aliphatic acid of wherein 3～10wt%12 or more carbon atoms.It is said that this fiber is easy to processing, do not need to apply finish in spinning or during stretching.

United States Patent (USP) 4,950,541 disclose a kind of linear ethylene polymer one maleic acid and maleic anhydride graft product that obtains by grafting maleic acid on LDPE (low density polyethylene (LDPE)), LLDPE or HDPE polymer or maleic anhydride.This graft polymers is for can dye and can be used as for example skin component of bicomponent fiber.

United States Patent (USP) 4,684,576 disclose grafting HDPE and the not preparation of grafting LLDPE or LDPE blend, and wherein HDPE has carried out grafting so that butanedioic acid or the succinic anhydride group along the HDPE polymer to be provided with maleic acid or maleic anhydride.According to open, this blend can be used for the production of laminate structures.

Now find unexpectedly, a kind of polyolefin bicomponent fiber, its low-melting component comprises the graft polyolefin composition of unsaturated dicarboxylic in non-graft polyolefin composition and the grafting or its acid anhydride, when being used to produce dried shop non-woven fabric material, have superior performance, comprise the strength character of making non-weaving cloth to the bonding of cellulosic pulp fibers and improvement of improvement.

Summary of the invention

One aspect of the invention relates to a kind of dried shop non-woven fabric material that comprises bicomponent fiber, this fiber comprises low melting point polyolefin component and high melting-point polyolefins component, wherein the fusing point of low melting point polyolefin component hangs down at least 4 ℃ than the fusing point of high melting-point polyolefins component, this low melting point polyolefin component constitutes at least a portion of fiber surface and comprises non-graft polyolefin composition and graft polyolefin composition, and wherein the graft polyolefin composition has carried out grafting with unsaturated dicarboxylic or its acid anhydride.

Another aspect of the present invention relates to a kind of method of doing the shop non-woven fabric material of producing, comprise adopting and do shop non-interlaced fabric equipment shaping fibre web, this fibre web comprises bicomponent fiber, this fiber comprises low melting point polyolefin component and high melting-point polyolefins component, wherein the fusing point of low melting point polyolefin component hangs down at least 4 ℃ than the fusing point of high melting-point polyolefins component, this low melting point polyolefin component constitutes at least a portion of fiber surface and comprises non-graft polyolefin composition and graft polyolefin composition, and wherein the graft polyolefin composition has carried out grafting with unsaturated dicarboxylic or its acid anhydride; Then, fibre web is bonding to form dried shop non-woven fabric material.

Another aspect of the present invention relates to and is used to produce the bicomponent fiber as mentioned above of doing the shop non-woven fabric material.

Detailed Description Of The Invention

The term " polyolefin component " that is used for the object of the invention be meant its largest portion (by weight) by the homopolymerization of monoene such as ethene, propylene, 1-butylene, 4-methyl-1-pentene-or copolymerization-polymer constitute contain the polyolefin polymers material.The example of this base polymer is polyethylene such as high density polyethylene (HDPE), low density polyethylene (LDPE) and the linear low density polyethylene (LLDPE) of isotaxy or syndiotactic polypropylene, different densities, and above-mentioned blend.This polymeric material can with other non-polyolefin polymers, mix mutually as polyamide or polyester, condition is the largest portion that polyolefin still constitutes composition.Be used to produce the melt that contains polyolefinic fiber and also can comprise various traditional fibre additives, as calcium stearate, antioxidant, processing stabilizers, compatilizer, and pigment, comprise brightening agent and colouring agent such as titanium dioxide etc.

Although for simply counting the formulation that " fiber " generally adopted in explanation of the present invention, promptly the staple fibre of Qie Duaning should be appreciated that the present invention will also be applicable to the production of polyolefin filaments such as spun-bonded continuous yarn.

Term " dry-laying (doing the shop) " non-weaving cloth is meant the non-woven fabric material that adopts dry production, comprises air-laid non-weaving cloth, combing non-weaving cloth etc.

Said bicomponent fiber can be a core-skin type, the both desirable off-centre of its SMIS (not at the center), and also desirable with one heart (being positioned at the center substantially) position, or parallel type, wherein each has semicircle section in typical case in 2 components.Also expect having the bicomponent fiber of irregular fiber section configuration, for example avette, oval, triangle, star, leafy shape or other irregular sections, and even but fibrilled film fibre.Typical bicomponent fiber often has high-melting-point and low melting point polyolefin component, they comprise respectively, polypropylene, polyethylene (polyethylene comprises HDPE, LDPE and/or LLDPE), high density polyethylene (HDPE)/linear low density polyethylene (LLDPE), polypropylene random copolymer/polyethylene or polypropylene/polypropylene random copolymer.

In some cases, for example work as 2 kinds of fibre fractionations and comprise high density polyethylene (HDPE)/linear low density polyethylene (LLDPE), perhaps during the polypropylene/polypropylene random copolymer, its fusing point is poor, be that fusing point difference between these 2 kinds of polyolefin component may be quite little, for example about 7～8 ℃, under some situation even be low to moderate about 4～5 ℃.Yet, usually preferably, differ at least about 20 ℃ between the 2 component fusing points, preferably at least about 25 ℃, more preferably at least about 28 ℃, for example at least about 30 ℃.

As mentioned above, the at present preferred aspect of the present invention relates to the dried shop non-woven fabric material that comprises the polyolefin bicomponent fiber, in this fiber, the low melting point polyolefin component comprises non-grafting composition and grafting composition, and this grafting composition has carried out grafting with unsaturated dicarboxylic or its acid anhydrides.The example of this type of acid and acid anhydrides is maleic acid, maleic anhydride and derivative thereof such as citraconic acid, citraconic anhydride and pyrocinchonic acid acid anhydride; Fumaric acid and derivative thereof; The unsaturated derivative of malonic acid, as the 3-butene-1,1-dicarboxylic acids, benzal malonic acid and isopropylidene malonic acid; And the unsaturated derivative of butanedioic acid, as itaconic acid and itaconic anhydride.

Maleic acid and maleic anhydride are especially preferred as dicarboxylic acids or its acid anhydride.When these compounds were grafted on the polyolefin chain, the chain of formation had just had butanedioic acid or succinic anhydride group that grafting is got on respectively.Dicarboxylic acids or its acid anhydrides can be grafted on the polyolefin according to original known method, and these methods for example can be referring to EP 0465203 above-mentioned, United States Patent (USP) 4,950,541 and United States Patent (USP) 4,684,576.

The weight ratio of graft polyolefin and non-graft polyolefin will be between about 1: 99～50: 50 in the low melting point polyolefin component of bicomponent fiber, about 1.5: 98.5～30: 70 of representative value, more typical about 2: 98～20: 80, for example about 3: 97～15: 85, for example about 5: 95～10: 90 scope.

Within graft polyolefin, the content of carboxylic acid or its acid anhydrides is generally in the scope of about 1～30wt%, representative value about 2～20%, more typical about 3～15%, for example about 5～10%.

Weight ratio between high-melting-point and the low melting point polyolefin component will be 10: 90～90: 10 scope, about 20: 80～80: 20 of representative value, more typical about 30: 70～70: 30, for example 35: 65～65: 35.

Mention above, the present invention who comprises polyolefin bicomponent fiber and natural fabric does the shop non-weaving cloth and is characterised in that, this bicomponent fiber is to the fusible improvement of natural fabric, it is definite that this is that the employing standard is fallen hair test (dust test), and result of the test reflects the bonding quality between these 2 types of fibers.In this code test, the linear velocity of employing 20 or 40m/min prepares the about 85g/m of basis weights ², the about 1.1mm of thickness dried shop non-weaving cloth sample, the raw material of employing is the mixture of 25wt% synthetic fiber to be measured and 75wt% cellulosic pulp fibers (for example, Weyerhauser produce NB 416).Non-weaving cloth to be measured adopts a series of different tack temperature (for example adopt hot-air or roll bonding, typically adopt hot-air oven) preparation usually, so that the performance of given non-weaving cloth is optimized.

The mensuration program that non-weaving cloth falls gross value is as follows.Before implementing to measure, non-weaving cloth sample to be measured carries out the Balance Treatment of 12h at least earlier, all is under the identical temperature and humidity condition to guarantee all samples.In view of, will illustrate as following, result of the test is represented as and contrasts sample relative value relatively usually, and definite temperature and relative humidity that the sample balance is adopted are not strict with, and both can as long as all samples that compares has all stood the Balance Treatment of the same terms.Therefore, can adopt environment temperature and damp condition.Carry out before the balance, non-weaving cloth is cut into the individual sample of size 12 * 30cm.After the balance, the cardboard lath of a wide 5mm is fixed on the minor face of sample, then, the sample band the cardboard lath and is weighed on the balance of the laboratory of accuracy ± 0.1mg together.Then, non-weaving cloth sample to be measured is fixed with the clip of 2 long 12cm, and each clip is installed on the arm.The exposed area of the non-weaving cloth that is fixed is about 310cm ², be substantially equal to the size of an A4 paper.One of 2 arms are fixed, and another arm is rotatable and is connected with spring.

The mensuration process is, rotatable arm is turned over 45 °, so that make the non-weaving cloth sample become " relaxing " state from " tension " state, then, decontrols rotatable arm, thereby makes rotatable arm turn back to its original position under spring action.The motion of arm is stopped by the non-weaving cloth sample, so sample just is subjected to a little vibration and stretching action, is intended to simulate the condition that is stood when non-weaving cloth twists in unwinding on the converting apparatus, and this vibration and stretching cause the loss of fiber surface loose fiber.Repeat this action 50 times.Certainly, the suffered tensile force of sample must be positioned within the elastic limit scope of non-weaving cloth, so that make non-weaving cloth remarkable deformation not take place or sustain damage at duration of test.By the same token and consider between the TENSILE STRENGTH of different non-weaving cloths that sizable variation is also arranged, the power that spring provided obviously also must be complementary with non-weaving cloth to be measured, so that make non-weaving cloth can turn back to its original elongation position and stand slight vibration and stretching on the one hand, unlikely but then excess elongation, so that deformation or impaired appears.

After having stood 50 vibration/stretching actions, the sample of weighing once more, calculate 2 times between the numerical value difference and be expressed as the milligram number of hair.

Fall in the hair test in this standard, the result who represents with milligram often is not more than about 15mg, typically is not more than about 10mg, preferably is not more than about 5mg, more preferably no more than about 4mg, further preferably is not more than about 3mg, most preferably is not more than about 2mg.For the good especially non-weaving cloth of affinity between those synthetic fiber and the natural fabric, this result can be low to moderate the hair that falls of about 1mg.

A kind of alternative and normally preferably define certain given fiber to fall the mode that reduces the performance of falling hair in the hair test in standard be to adopt, compare with the similar non-weaving cloth of the like fibrous preparation that does not contain the graft polyolefin composition, fall the minimizing of gross weight (milligram) by the standard non-weaving cloth of fiber production of the present invention.In this case, should show with the contrast non-weaving cloth that adopts the contrast fiber production by the non-weaving cloth of fiber production of the present invention and to compare, reduce at least about the hair that falls of 40wt%, typically at least about 50wt%.Preferably, fall mao minimizing value, more preferably at least about 70%, further preferably at least about 80% at least about 60%.For the fiber good especially with the cellulose bond properties, falling mao minimizing value can be up to about 90% or higher.In view of according to such as the person's character of the person's character of bicomponent fiber and cellulose or other fibers and even such as be shaped different with factor such as adhesive bonding method of concrete fibre web, a certain given non-weaving cloth fall that mao performance can great changes have taken place, so when the performance of more given fiber, preferably adopt the hair of comparing with similar contrast fiber to reduce percentage, and the absolute value of not representing in order to milligram.

Imagination also, the improvement of bonding and the fixation of fiber of the present invention not only shows on the cellulose fibre, and shows on the various different superabsorbent polymers (SAP) to the particle used always in the sanitary absorbent article or fibers form.This type of SAP, for example crosslinked salt polyacrylate uses with the superabsorbent particles form in the absorbent core such as throw-away nappy usually, because they can suck the liquid that is several times as much as own wt and form the gel that maintains this liquid after drenching.Even fiber of the present invention is not direct and the SAP particle is bonding, also can imagine, bonding improvement will cause a kind of structure of improvement, itself just to play to guarantee to make the SAP particle maintain the effect that requires the position in the absorbent article fiber of the present invention to cellulose fibre, thereby improve the function of SAP.

The spinning of this fiber preferably adopts traditional melt spinning (also claim " long spin ") to finish, and spinning is carried out with being stretching in 2 steps of separating.Alternatively, other make the mode of staple fibre, and particularly " compact (short distance) spinning ", promptly the single stepping method also can be used for implementing the present invention.The spinning process of bicomponent fiber and long filament is known technically.It is tow through extrusion molding that these class methods relate generally to melt, and tow is handled tow so that the surface nature that obtains to require through cooling and stretching with suitable spinning oil, for example, adopt spinning oil, when fiber is prepared to be used for absorbent core, provide hydrophily, and/or antistatic property is provided, then, tow is stretched, handle tow with second spinning oil more in typical case, again through deformation processing, drying is also cut off tow, obtains staple fibre at last.

As noted above, typical the present invention does the shop non-weaving cloth, except that the polyolefin bicomponent fiber, also comprise at least a kind of additional fibers material, particularly natural fabric or regenerated fiber, but as be selected from cellulose fibre, viscose rayon fibers and profit fiber (it is the fiber of being made by wood pulp).This cellulose fibre for example can be pulp fibers or cotton fiber, particularly pulp fibers, as CTMP (chemistry-Re-mechanical pulp), sulfite pulp or kraft pulp.

The fibre web that contains bicomponent fiber and additional fibers material generally comprises 5～50wt% bicomponent fiber and 50～95wt% additional fibers material, more typically 10～40wt% bicomponent fiber and 60～90wt% additional fibers material, for example 15～25wt% bicomponent fiber and 75～85wt% additional fibers material.

Embodiment

Embodiment 1

Different polyolefin bicomponent fibers is tested, but to assess its cohesiveness to cellulosic pulp fibers.

Cellulose fibre is NB 416, is provided by Weyerhauser company.Weight ratio between bicomponent fiber and the cellulose fibre is 25: 75.

Bicomponent fiber composed as follows of test,

No. 1 fiber is according to of the present invention:

1: core: polypropylene; Skin: 10% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 90%LLDPE.

2. contrast fiber; Core: polypropylene; Skin: 100%LLDPE.

3.AL-Special-C, provide by Danaklon A/S; Polypropylene cores, the HDPE skin.

4.Hercules 449, Hercules company provides, length 5mm, fiber number 1.5 dtexs; Polypropylene cores/polyethylene sheath.

Bicomponent fiber 1,2 and 3 all is: fiber number 1.7 dtexs, length 6mm, core-Pi weight ratio 35: 65.

Fiber is with low-down speed, and 8.33m/min goes up operation at air-laid equipment (Dan-Web, Denmark), because the main purpose of this test is to investigate this fiber to cellulosic adhesive power.Duration of test, the target fabric Unit Weight of air-laid nonwoven product is 80g/m ², test is from minimum as far as possible tack temperature, and then, the oven interior temperature raises with 5 or 10 ℃ interval.

The result:

Horizontal (CD) dry strength of the sample that has prepared under the different temperatures shown in below having measured, vertical (MD) dry strength and MD wet strength (EDANA test method 20.2-89 tests under the speed of 100mm/min).In addition, each sample thickness and basis weights (g/m have also been measured ²), and with these data (not listing below) correction intensity value, although obtained on each sample thickness and basis weights, minute differences to be arranged but still the normalization numerical value that can compare.

Tack temperature MD intensity CD intensity MD is wet strong

Sample number ℃ N/5cm N/5cm N/5cm

1 125 25.9 25.2 25.4

1 130 20.9 20.5 18.3

1 135 23.5 22.4 20.6

1 140 23.1 22.3 20.1

1 145 23.9 22.5 18.0

2 125 17.46 15.43 15.13

2 130 13.63 13.32 11.62

2 135 15.17 15.06 12.66

2 140 16.25 15.72 13.49

2 145 12.77 13.08 9.78

2 150 11.28 10.77 6.77

2 155 4.15 4.26 2.23

3 130 24.01 23.37 23.59

3 140 19.34 18.08 18.57

3 150 15.59 16.66 14.42

4 130 7.98 7.78 7.98

4 140 9.23 7.93 8.73

4 150 8.83 8.93 8.83

4 160 4.21 4.31 2.26

4 170 3.24 3.14 1.27

Fall mao result of the test following (mean value of 2 tests, but No. 3 fiber exceptions, it is the scope of carrying out result that relatively large test number (TN) is obtained with this fiber):

Fiber number Fall hair (mg)

1 1.7

2 7.4

3 12～30

4 14.0

Compare with contrast PP/PE fiber 2,3 and 4, in falling the hair test, provided the result of remarkable improvement, the remarkable improvement that has reflected that bicomponent fiber of the present invention is bonding to the cellulose fluff pulp fibres that significantly reduces that produces hair according to fiber 1 of the present invention.Microscopic examination to sample also discloses the bonding of bicomponent fiber of the present invention and cellulose fibre.Also find, the non-weaving cloth that fiber 1 is made and fiber 2 with 3 compare more fluffy (fiber 4 is not done the comparison of this respect).And as above shown in the strength values that provides in the table, the non-weaving cloth that fiber of the present invention is made has the intensity and the elongation characteristics of improvement.

Embodiment 2

On a commercial scale air-laid production line, tested the adhesive power of 2 kinds of different fibers to cellulose fibre.Prepared the about 80g/m of basis weights ², the about 1mm of thickness the air-laid non-weaving cloth.This non-weaving cloth comprises 25wt% bicomponent fiber and 75wt% cellulosic pulp fibers.The bicomponent fiber fiber number of test is 1.7 dtexs, length 6mm.Except above-mentioned (contrast) fiber 3, also tested a kind of bicomponent fiber (being called No. 5), it has the additive of the binder fiber element identical with fiber 1, but has the higher polyethylene sheath component (HDPE) of fusing point.The fiber of so making has following composition:

5: core: polypropylene; Skin: 10% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 90%HDPE.

The various different temperatures that each non-weaving cloth sample is 3 ℃ at the interval are carried out bonding, so that determine the optimum adhesion temperature of every kind of fiber.

Find that the non-weaving cloth that comprises bicomponent fiber of the present invention (fiber 5) shows improved bonding to cellulose fibre, during processing, produce as comparing that hair reduces (not the doing quantitative assay in this test) that proved with the contrast fiber.And the non-weaving cloth that fiber of the present invention is made has obtained improved strength characteristics, and result of the test proved as following:

MD dry tensile strength (N/5 cm)

The tack temperature fiber

℃ Contrast 5

137 13.96 15.08

140 15.77 19.01

143 12.56 19.40

146 - 15.41

Embodiment 3

The purpose of carrying out this test is to show the influence that changes additive (maleic acid is grafted on the LLDPE, active quantities 5%) content in the skin component.

The bicomponent fiber of test all is fiber number 1.7 dtexs, length 6mm.Core-Pi weight ratio is 35: 65 concerning fiber 6～9; To fiber 10, it is 50: 50.The core of all situations is polypropylene.Non-weaving cloth is to adopt the technology of Dan-Web company (Denmark) to produce on commercial scale air-laid production line, and the non-weaving cloth Unit Weight is about 80g/m ², the about 1mm of its thickness, bicomponent fiber is 25: 75 to the weight ratio of cellulose fibre.Comprise under the condition of--137,140 and 143 ℃--in sample of every kind of bicomponent fiber and test 3 kinds of different tack temperature.

The skin component of every kind of fiber is composed as follows:

6:5% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 95%LLDPE.

7:5% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 95%HDPE.

8:10% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 90%HDPE.

9:12.5% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 87.5%HDPE.

10:13% grafting LLDPE (5% maleic acid is grafted on the 95%LLDPE), 87%HDPE.

Sample adopts AL-Special-C as a comparison, provides (polypropylene cores, HDPE skin by Danaklon A/S; As above-mentioned No. 3).

Wet, the dry tensile strength and the elongation of various non-weaving cloths have been tested.Shown in following result, the non-weaving cloth that comprises fiber of the present invention shows and contrasts non-weaving cloth and compare significantly improved doing and wet tensile strength.In addition, some in the fiber of the present invention, especially 6,7 and 8, show and be higher than contrast elongation of fiber value, and fiber 10 and fiber 9 to a certain extent, show and be lower than contrast elongation of fiber value.Fiber 9 and 10 unsatisfactory performance aspect elongation, it is believed that relevant with the following fact: these fibers that contain more grafting composition in cortex run into certain difficulty in spinning.The author believes, if spinning technique and other technological parameters are further tested and are optimized, these and other have big graft polyolefin component content fiber also can obtain improved result.

Dry tensile strength (N/5 cm)
Dry tensile strength (N/5 cm)							Tack temperature ℃	The contrast sample	Fiber number
6	7	8	9	10					Fiber number
6	7	8	9	10	137	8.54			21.58	17.65	16.91	18.68	12.75
140	9.85	18.58	20.98	17.00	137	8.54	17.95	14.40	21.58	17.65	16.91	18.68	12.75
140	9.85	18.58	20.98	17.00	143	8.53	17.95	14.40	18.59	19.25	30.63	18.18	16.38

Stem elongation (%)
Stem elongation (%)							Tack temperature ℃	The contrast sample	Fiber number
6	7	8	9	10					Fiber number
6	7	8	9	10	137	185.25			190.25	154.50	199.67	174.25	133.50
140	175.00	184.75	188.25	195.67	137	185.25	169.00	119.00	190.25	154.50	199.67	174.25	133.50
140	175.00	184.75	188.25	195.67	143	178.67	169.00	119.00	189.25	185.78	184.25	185.75	144.75

Wet tensile strength (N/5cm)
Wet tensile strength (N/5cm)							Tack temperature ℃	The contrast sample	Fiber number
6	7	8	9	10					Fiber number
6	7	8	9	10	137	8.24			17.57	15.21	16.03	17.11	9.39
140	9.32	13.64	17	13.78	137	8.24	16.31	10.19	17.57	15.21	16.03	17.11	9.39
140	9.32	13.64	17	13.78	143	8.01	16.31	10.19	15.34	15.2	24.08	17.04	16.31

Wet elongation (%)
Wet elongation (%)							Tack temperature ℃	The contrast sample	Fiber number
6	7	8	9	10					Fiber number
6	7	8	9	10	137	175.25			220.75	161.50	179.67	205.25	118.75
140	159.50	194.25	177.75	186.75	137	175.25	189.00	132.50	220.75	161.50	179.67	205.25	118.75
140	159.50	194.25	177.75	186.75	143	142.50	189.00	132.50	196.00	179.67	177.00	188.50	123.75

Show with the assessment of falling mao performance of naked eyes non-weaving cloth, the bicomponent fiber of the present invention of all tests all have contrast bicomponent fiber that improve with cohesiveness cellulose fibre.Fiber 7 and 8 carries out especially smoothly on production line, and as shown in the top result, the non-weaving cloth that comprises these fibers has also obtained excellent intensity level.

The result of present embodiment fiber in falling the hair test following (fiber 10 is not measured):

Fiber number falls hair (mg)

6 6.6

7 14.9

8 5.8

9 6.7

Contrast sample 29.9

Can draw as drawing a conclusion from above result, on all additive addition levels, all obtain good result, though as if there is the tendency of better effects in about 5～10% addition scope.

Claims

1. dry-laying non-woven fabric material, comprise bicomponent fiber and at least a kind of additional fibers material, described bicomponent fiber comprises low melting point polyolefin component and high melting-point polyolefins component, wherein the fusing point of low melting point polyolefin component hangs down at least 4 ℃ than the fusing point of high melting-point polyolefins component, the low melting point polyolefin component constitutes at least a portion of fiber surface and comprises non-graft polyolefin composition and graft polyolefin composition, and wherein the graft polyolefin composition has carried out grafting with unsaturated dicarboxylic or its acid anhydrides.

2. according to the dry-laying non-woven fabric material of claim 1, wherein the graft polyolefin composition of bicomponent fiber has carried out grafting to be selected from following compound: maleic acid, maleic anhydride and derivative thereof; Fumaric acid and derivative thereof; The unsaturated derivative of malonic acid; And the unsaturated derivative of butanedioic acid.

3. according to the dry-laying non-woven fabric material of claim 2, wherein the graft polyolefin composition of bicomponent fiber has carried out grafting with maleic acid or maleic anhydride.

4. according to any one dry-laying non-woven fabric material in the above claim, wherein bicomponent fiber is a core-skin fibre, and wherein the low melting point polyolefin component constitutes skin, and the high melting-point polyolefins component constitutes core.

5. according to any one dry-laying non-woven fabric material in the above claim, wherein this at least a kind of additional fibers material is selected from natural fabric and regenerated fiber.

6. according to the dry-laying non-woven fabric material of claim 5, wherein the additional fibers material comprises the cellulose fluff pulp fibres.

7. according to any one dry-laying non-woven fabric material in the above claim, wherein the high melting-point polyolefins component comprises polypropylene, and the low melting point polyolefin component comprises at least a kind of polyolefin that is selected from LLDPE, HDPE and LDPE.

8. according to any one dry-laying non-woven fabric material in the above claim, wherein fusing point differs at least about 20 ℃ between the low-melting component of bicomponent fiber and the high melting point component.

9. according to any one dry-laying non-woven fabric material in the claim 1～6, wherein the high melting-point polyolefins component comprises first polypropylene, and the low melting point polyolefin component comprises second polypropylene or polypropylene copolymer, and the fusing point of second polypropylene or polypropylene copolymer is than first polyacrylic low at least 5 ℃.

10. according to any one dry-laying non-woven fabric material in the above claim, wherein fibre web comprises 5～50wt% bicomponent fiber and 50～95wt% additional fibers material.

11. method of producing the dry-laying non-woven fabric material, comprise and adopt dry-laying non-interlaced fabric equipment shaping fibre web, this fibre web comprises bicomponent fiber and at least a kind of additional fibers material, described bicomponent fiber comprises low melting point polyolefin component and high melting-point polyolefins component, wherein the fusing point of low melting point polyolefin component hangs down at least 4 ℃ than the fusing point of high melting-point polyolefins component, the low melting point polyolefin component constitutes at least a portion of fiber surface and comprises non-graft polyolefin composition and graft polyolefin composition, and wherein the graft polyolefin composition has carried out grafting with unsaturated dicarboxylic or its acid anhydrides; And implement bonding to make the dry-laying non-woven fabric material to fibre web.

12. according to the method for claim 11, wherein this additional fibers material is selected from natural fabric and regenerated fiber.

13. according to the method for claim 12, wherein the additional fibers material comprises the cellulose fluff pulp fibres.

14. according to any one method in the claim 11～13, wherein the graft polyolefin composition of bicomponent fiber has carried out grafting to be selected from following compound: maleic acid, maleic anhydride and derivative thereof; Fumaric acid and derivative thereof; The unsaturated derivative of malonic acid; And the unsaturated derivative of butanedioic acid.

15. according to the method for claim 14, wherein the graft polyolefin composition of bicomponent fiber has carried out grafting with maleic acid or maleic anhydride.

16. according to any one method in the claim 11～15, wherein bicomponent fiber is a core-skin fibre, wherein the low melting point polyolefin component constitutes skin, and the high melting-point polyolefins component constitutes core.

17. according to any one method in the claim 11～16, wherein the high melting-point polyolefins component comprises polypropylene, and the low melting point polyolefin component comprises at least a kind of polyolefin that is selected from LLDPE, HDPE and LDPE.

18. according to any one method in the claim 11～17, wherein fusing point differs at least about 20 ℃ between the low-melting component of bicomponent fiber and the high melting point component.

19. according to any one method in the claim 11～16, wherein the high melting-point polyolefins component comprises first polypropylene, and the low melting point polyolefin component comprises second polypropylene or polypropylene copolymer, and the fusing point of second polypropylene or polypropylene copolymer is than first polyacrylic low at least 5 ℃.

20. according to any one method in the claim 11～19, wherein fibre web comprises 5～50wt% bicomponent fiber and 50～95wt% additional fibers material.

21. bicomponent fiber that is used to produce the dry-laying non-woven fabric material, this fiber comprises low melting point polyolefin component and high melting-point polyolefins component, wherein the fusing point of low melting point polyolefin component hangs down at least 4 ℃ than the fusing point of high melting-point polyolefins component, the low melting point polyolefin component constitutes at least a portion of fiber surface and comprises non-graft polyolefin composition and graft polyolefin composition, and wherein the graft polyolefin composition has carried out grafting with unsaturated dicarboxylic or its acid anhydrides.

22. according to each dry-laying non-woven fabric material among the claim 1-10, comprise bi-component synthetic fiber and natural or regenerated fiber material, this bicomponent fiber comprises low melting point polyolefin component and high melting-point polyolefins component, wherein the fusing point of low melting point polyolefin component hangs down at least 4 ℃ than the fusing point of high melting-point polyolefins component, the low melting point polyolefin component constitutes at least a portion on bicomponent fiber surface, this bicomponent fiber has the bonding affinity to natural or regenerated fiber, thereby the gross value that falls that this non-woven fabric material is fallen in the hair test in standard described herein is not more than 10mg.