Patent Application
20150292144
The present invention relates to compositions, preferably in the form of spin finishes, for polyolefin fibers or filaments imparting to these basically hydrophobic fibers permanently hydrophilic properties, as well as to fibers and filaments finished with these compositions, and to textile fabrics made thereof, in particular nonwoven fabrics.
Hydrophilic nonwoven fabrics are used as covering fibrous webs, i.e. as the top layer or as an intermediate layer in multi-layer fibrous webs, for hygiene products such as baby diapers, sanitary napkins, incontinence products and similar products. It is the task of such nonwovens to quickly pass body fluids such as urine to the underlying absorption layer.
Ordinary hydrophilizing preparations are wiped off the nonwoven fabric more or less quickly and distinctly during fluid transport within the diaper or other product, making the covering fibrous web gradually lose its hydrophilic properties and, due to the hydrophobic properties of polyolefins, become more and more hydrophobic. Upon subsequent further contact with body fluids, the passing of said fluids to the absorption layer will be increasingly complicated and finally impossible. As a result, the fluids leak from the nonwoven construct, and the nonwoven construct can no longer exert its original function of keeping a baby's or a patient's skin dry.
In contrast to that, a preparation for permanent hydrophilization is supposed to adhere to the polyolefin as long as possible and impart to the nonwoven fabric a consistent hydrophilicity over a long time.
Typically, nonwoven fabrics are made of filaments and/or fibers, with random-laid fiber nonwovens bonded by either physical methods such as needling or by chemical means. In the production of carded nonwovens that are subsequently heat-set a hydrophilizing fiber preparation must additionally meet further requirements. In this case, for nonwovens to be produced at an acceptable rate, the preparation must permit fiber production and processing and also impart to the fibers and filaments optimum sliding properties and cohesion, and provide them with a sufficient antistatic finish.
U.S. Pat. No. 4,988,449 describes hydrophilizing compositions that contain diethanol amides such as non-ionic surfactants, alkyl phosphates, quaternary ammonium salts and/or alkyl imidazolium salts and are used as agents imparting fluid permeability to polyolefin nonwovens.
From U.S. Pat. No. 5,258,129 hydrophilizing compositions are known that contain polyoxyalkylene-modified polydimethylsiloxanes alone or in combination with non-ionic surfactants, alkyl phosphates, quaternary ammonium salts and/or alkyl imidazolium salts.
EP 410 485 B1 discloses a method for hydrophilizing polyolefin fiber nonwovens by applying to the surface of the fibers an aqueous mixture of alkoxylated surfactants, wherein the composition consists either of at least 80% alkoxylated triglycerides of C18 fatty acids, with these triglycerides containing a large proportion of alkoxylated ricinolein or alkoxylated and hydrogenated ricinolein, or of at least 80% of a mixture of alkoxylated or alkoxylated and hydrogenated ricinolein, a polyalkylene-modified water-soluble polydimethylsiloxane and an antistatic compound, the latter being for example a neutralized phosphoric acid ester, an alkoxylated phosphate, potassium salt, ammonium salt or an alkyoxylated ammonium salt.
From EP 0 839 947 A2 hydrophilizing compositions are known that contain non-ionic surfactants in combination with a polyoxyalkylene-modified polydimethylsiloxane and/or a quaternary ammonium compound.
EP 1 600 532 B1 describes hydrophilizing compositions comprising an alkoxylated glycerol esterified with a fatty acid and an alkoxylated or alkoxylated and hydrogenated ricinolein esterified with a fatty acid.
Although these known compositions impart to the fibers and nonwoven fabrics treated or finished with them permanently hydrophilic properties, their production is expensive and they need to be improved with regard to the rate at which the fluid is passed through the nonwoven fabric into the absorption layer.
Furthermore, there is a need for compositions hydrophilically finishing fibers and nonwoven fabrics that are resistant to migration of constituents in the preparation, whether dry and/or wet, to adjacent hydrophobic areas of the nonwoven.
Thus, it is the object of the invention to provide a composition with good permanently hydrophilizing properties, a rapid transit capacity and a low tendency to migrate into adjacent hydrophobic areas of the nonwoven fabric.
According to the present invention, this object is solved by a composition for permanently hydrophilizing polyolefin fibers and filaments and textile fabrics made thereof such as nonwoven fabrics and other nonwoven textile products according to claim 1.
Further advantageous embodiments are stated in the sub-claims which can be optionally combined with each other.
The composition for permanently hydrophilizing polyolefin fibers and filaments and textile fabrics made thereof comprises:
(A) 15 to 50% by weight of at least one non-ionic surfactant, wherein the non-ionic surfactant is selected from the following group of compounds, each having one or more branched or straight-chain, saturated or unsaturated C6-C18 hydrocarbon chains in their molecule: alkoxylated C6-C18 fatty alcohols, alkoxylated C6-C18 amines, alkoxylated C6-C18 amides, alkoxylated C6-C18 fatty acids, alkoxylated C6-C18 fatty acid esters and alkoxylated C8-C18 alkylphenoles;
(B) 15 to 50% by weight of at least one quaternary ammonium compound of the general formula (I):
[R1—C(═O)—X—(CH2)n—NR2R3—(CH2)m—X—C(═O)—R1]+Y− (I)
wherein
R1 is an alkyl group having 1 to 22 C atoms or an alkenyl group having 2 to 22 C atoms,
R2 and R3 independently represent an alkyl group having 1 to 22 C atoms, hydroxyethyl or a polyglycol radical,
X is an oxygen atom, NH, N—CH3 or a (OC2H4)z group with z=1 to 10,
Y− is one of the anions CH3OSO3−, C2HSOSO3−, CH3COO−, Cl−, phosphate, lactate, citrate, and
m and n independently represent an integer from 1 to 6;
wherein the quaternary ammonium compound is present as a solid at room temperature (20° C.);
(C) 15 to 50% by weight of at least one neutralized phosphoric acid ester of the general formula (II):
P(═O)(OR4)(OR5)(OR6) (II)
wherein
R4, R5 and R6 independently represent
As a neutralizing agent for the phosphoric acid ester, all suitable bases such as LiOH, NaOH, KOH, NH3, mono-, di- or triethanolamine can be used.
The composition according to the present invention has excellent permanently hydrophilizing properties, an excellent transit capacity and a good resistance to migration of the constituents in the preparation to adjacent hydrophobic areas of the nonwoven fabric.
In aqueous dilutions, these compositions can be used particularly well as fiber preparations for the permanent hydrophilic finishing of polyolefin fibers, polyolefin filaments and nonwoven textile products made thereof, in particular nonwoven fabrics.
The non-ionic surfactant in component (A) of the composition according to the present invention is preferably selected from the group of fatty alcohol alkoxylates having 6 to 18 C atoms in the hydrocarbon chain. Particularly preferred are fatty alcohol alkoxylates having 8 to 16 C atoms in the hydrocarbon chain.
The fatty alcohol alkoxylates can have a hydroxyl or an alkyl or alkenyl ether group as a terminal group. Particularly preferred are hydroxyl group-terminated fatty alcohol alkoxylates.
The number of alkoxy groups in the non-ionic surfactant of component (A) is preferably 1 to 10, more preferably 2 to 8 and particularly preferably 2 to 6. The alkoxy groups are preferably ethyl(ene)oxy (EO) and/or propyl(ene)oxy (PO) groups, particularly preferably EO groups.
In the quaternary ammonium compound of component (B) the radicals R1 to R3 in formula (I) are preferably alkyl groups as derived from vegetable oils and oil blends. It is particularly preferred that the radicals R1, R2, and R3 are derived from vegetable oils with a high proportion of saturated fatty acids, in particular palm oil or palm kernel oil.
According to the present invention, the quaternary ammonium compounds are present as a solid at room temperature.
According to a particularly preferred embodiment of the composition according to the present invention the quaternary ammonium compounds have a melting point of 25 to 80° C., particularly preferably a melting point of 30 to 50° C.
At least one of the radicals R4, R5 and R6 in formula (II) of the neutralized phosphoric acid ester of component (C) is preferably an alkoxylated alkyl or alkenyl group having 6 to 18 C atoms in the hydrocarbon chain and 1 to 6 alkoxy groups, particularly preferably an alkoxylated alkyl or alkenyl group having 10 to 18 C atoms in the hydrocarbon chain and 1 to 4 alkoxy groups. The alkoxy groups are preferably ethyl(ene)oxy (EO) and/or propyl(ene)oxy (PO) groups, particularly preferably EO groups.
According to another preferred embodiment at least one of the radicals R4, R5 and R6 in formula (II) is an alkyl group or an alkenyl group having 6 to 18 C atoms, particularly preferably having 10 to 18 C atoms.
In addition, the composition according to the present invention can optionally contain further additives from the group of cohesion agents, lubricants, corrosion inhibitors and emulsifiers as component (D).
Preferably, the composition according to the present invention consists of components (A), (B) and (C) as well as optionally one or more of the additives according to component (D). Particularly preferably, component (A) is present in a proportion of 20 to 35% by weight, component (B) is present in a proportion of 20 to 35% by weight and component (C) is present in a proportion of 35 to 45% by weight, each based on the total weight of components (A), (B) and (C).
The other additives of component (D) can be added to both the composition according to the present invention comprising components (A), (B) and (C) and the application liquor.
Preferably, a castor oil alkoxylate, for example Emulsogen EL 360 from Clariant, or a castor oil alkoxylate having up to 10 ethoxy and up to 3 propoxy units is used as a cohesion agent. The proportion of the cohesion agent in the composition according to the present invention is preferably 1 to 10% by weight, based on the total weight of the composition.
It is preferred that the cohesion agent is added subsequently to the application liquor.
Preferably, the lubricant is a fatty acid ethoxylate, particularly preferably a coconut fatty acid alkyoxylate such as Genagen C100 from Clariant, a coconut fatty acid having up to 10 ethoxy units or a coconut fatty acid having up to 10 ethoxy and 3 propoxy units. The proportion of the lubricant in the composition according to the present invention is preferably 1 to 10% by weight, based on the total weight of the composition.
It is preferred that the lubricant is added subsequently to the application liquor.
Preferably, a fatty acid amine derivative is used as a corrosion inhibitor for the protection of the metal parts of the spinning machines and the other processing machines, e.g. of the card. Particularly preferably, the corrosion inhibitor is an oleyl sarkosinate. The proportion of the corrosion inhibitor in the composition according to the present invention is preferably 0 to 2% by weight, based on the total weight of the composition.
It is preferred that the corrosion inhibitor is added subsequently to the application liquor.
As the emulsifier, a fatty acid ethoxylate is again preferably used, particularly preferably a coconut fatty acid alkyoxylate such as Genagen C100 from Clariant, a coconut fatty acid having up to 10 ethoxy units or a coconut fatty acid having up to 10 ethoxy and 3 propoxy units. The proportion of the emulsifier in the composition according to the present invention is preferably 1 to 50% by weight, based on the total weight of the composition.
Preferably, the composition according to the present invention is present in the form of an aqueous dispersion or paste whose drying residue at 105° C. is between 5 and 95% by weight.
The composition according to the present invention is preferably used as a fiber preparation for permanently hydrophilizing polyolefin fibers or polyolefin filaments or as an agent for the permanent hydrophilic finishing of nonwoven textile products made of polyolefin fibers or polyolefin filaments.
As the polyolefin, ethylene- or propylene-based homo- or copolymers can be used.
Examples of such polyolefins are polyethylenes such as HDPE (high-density polyethylene), LDPE (low-density polyethylene), VLDPE (very low-density polyethylene), LLDPE (linear low-density polyethylene), MDPE (medium-density polyethylene), UHMPE (ultra-high molecular polyethylene), VPE (cross-linked polyethylene), HPPE (high-pressure polyethylene); polypropylenes such as isotactic polypropylene, syndiotactic polypropylene, metallocene-catalyzed polypropylene, impact strength-modified polypropylene; ethylene- and propylene-based random copolymers, ethylene- and propylene-based block copolymers; EPM (poly[ethylene-co-propylene]); EPDM (poly[ethylene-co-propylene-co-conjugated diene]).
Further suitable polyolefins are, for example, polystyrene;
poly(methylstyrene); poly(oxymethylene); metallocene-catalyzed alpha-olefin or cycloolefin copolymers such as norbornene-ethylene copolymers; copolymers containing at least 60% ethylene and/or styrene and less than 40% monomers such as vinyl acetate, acrylic acid ester, methacrylic acid ester, acrylic acid, acrylonitrile or vinyl chloride. Examples of such polymers are poly(ethylene-co-ethyl acrylate), poly(ethylene-co-vinyl acetate), poly(ethylene-co-vinyl chloride) and poly(styrene-co-acrylonitrile).
Graft copolymers such as polymer blends, i.e. mixtures of polymers which contain, inter alia, the above-mentioned polymers, for example polyethylene- and polypropylene-based polymer blends, are also suitable. In addition, bi-component fibers with a core/shell structure such as PE/PP and PP/PET biopolymers can be used.
The composition according to the present invention can be applied to the fibers, filaments or nonwoven textile products in the form of an aqueous emulsion or in the form of an aqueous dispersion, preferably in an amount of 0.1 to 2%, based on the dry weight of the respective product (fiber, filament, nonwoven fabric).
As known to those skilled in the art, the composition is applied by means of metering pins, kiss rollers, dip baths or by spraying. Any viscosity desired for the respective application form can be adjusted by diluting the composition with water.
Therefore, polyolefin fibers and filaments that are permanently hydrophilically finished or treated with the composition according to the present invention are also an object of the invention.
In addition, the invention relates to a double finish and treatment of the polyolefin fibers/filaments and nonwoven textile products in which the composition according to the present invention initially provides the fibers or filaments and subsequently the entire nonwoven textile or fabric made thereof with a permanently hydrophilic finish.
It is particularly preferred that the nonwoven fabrics finished according to the present invention are non-bonded random-laid fiber nonwovens or chemically or physically bonded, e.g. needled or heat-set nonwovens.
Below, the invention is explained by means of several preferred embodiments, which, however, are not to be construed as limiting.
Component A
34.2% by weight C10 fatty alcohol polyethylene glycol ether-4EO (non-ionic surfactant)
Component B
28.2% by weight dkpalmcarboxyethylyhydroxyethyl-methylammonium-methosulfate (quaternary ammonium compound derived from palm fatty acid; melting point: 35° C.)
Component C
37.6% by weight mono- and di-(C12-C18)-alkyl phosphoric acid ester, potassium salt
Components A, B and C were thoroughly mixed, homogenized and optionally neutralized. The composition obtained this way was diluted with distilled or demineralized water, forming a dispersion containing 5% by weight of the composition.
Component A
24.1% by weight C12-C14 fatty alcohol polyethylene glycol ether-(3EO)
Component B
32.0% by weight dkpalmcarboxyethylyhydroxyethyl-methylammonium-methosulfate
Component C
43.9% by weight mono- and di-(C12-C18)-alkyl phosphoric acid ester, potassium salt
Components A, B and C were thoroughly mixed, homogenized and optionally neutralized. The composition obtained this way was diluted with distilled or demineralized water, forming a dispersion containing 5% by weight of the composition.
Component A
34.2% by weight bis-isooctyl sodium sulfosuccinate (ionic surfactant)
Component B
28.2% by weight dkpalmcarboxyethylyhydroxyethyl-methylammonium-methosulfate
Component C
37.6% by weight mono- and di-(C12-C18)-alkyl phosphoric acid ester, potassium salt
Components A, B and C were thoroughly mixed, homogenized and optionally neutralized. The composition obtained this way was diluted with distilled or demineralized water, forming a dispersion containing 5% by weight of the composition.
Component A
24.0% by weight C12-C14 fatty alcohol polyethylene glycol ether-6EO (non-ionic-surfactant)
Component B
32.5% by weight di-(oleylcarboxyethyl)-hydroxyethyl-methylammonium-methosulfate (quaternary ammonium compound; melting point: <20° C.)
Component C
43.5% by weight mono- and di-(C12-C18)-alkyl phosphoric acid ester, potassium salt
Components A, B and C were thoroughly mixed, homogenized and optionally neutralized. The composition obtained this way was diluted with distilled or demineralized water, forming a dispersion containing 5% by weight of the composition.
Component A
34.2% by weight bis-isooctyl sodium sulfosuccinate (ionic surfactant)
Component B
28.2% by weight di-(oleylcarboxyethyl)-hydroxyethyl-methylammonium-methosulfate
Component C
37.6% by weight mono- and di-(C12-C18)-alkyl phosphoric acid ester, potassium salt
Components A, B and C were thoroughly mixed, homogenized and optionally neutralized. The composition obtained this way was diluted with distilled or demineralized water, forming a dispersion containing 5% by weight of the composition.
A permanently hydrophilizing fiber preparation from Schill+Seilacher GmbH, Boblingen, commercially available under the designation Silastol™ PHP 20 and essentially comprising a mixture of cationic antistatic agents, non-ionogenic emulsifiers and special wetting agents, was used as another specimen.
A fiber preparation according to the compositions described in U.S. Pat. No. 4,988,449 was made comprising an alkyl diethanolamide, a salt of an acidic alkyl phosphoric acid ester, a non-ionic surfactant and a quaternary modified polydimethylsiloxane.
A permanently hydrophilizing fiber preparation on the basis of fatty acid polyethylene glycol esters that is commercially available under the designation Stantex™ S 6327 (Pulcra Chemicals) was used as another specimen.
Investigation of Hydrophilizing Properties
All preparations described above were adjusted, by dilution with distilled or demineralized water, to a dispersion containing 5% by weight active components. The 5% by weight active dispersion of the compositions according to Examples 1 and 2 and Comparative examples 1 to 6 was used as a fiber preparation for the permanent hydrophilic finishing of a polypropylene (PP) spunbond nonwoven with an area density of 15 g/m2. The applied weight of the active substance (OPU or oil pick up), based on the dry weight of the PP nonwoven, was 0.45 to 0.65%.
For the testing of the compositions in conjunction with the above-mentioned textile substrate the studies described below were performed.
Strike-Through Time
According to the EDANA method ERT 150.2-93, the time required for 5 ml of a synthetic urine solution to penetrate a prepared nonwoven fabric and enter the underlying absorption layer made of filter paper is measured. To find out whether the hydrophilic finish provided is washed out or indeed imparts permanent hydrophilicity, five successive measurements are made on the same fabric, with the absorbent filter paper renewed each time. The five measured values are given in seconds.
Wetback
According to the EDANA method ERT 151.0-93, the amount (in grams) of fluid flowing back into an overlying dry filter paper when a 4 kg load is placed on a soaked fabric is measured.
Runoff Test
Based on the EDANA method 152.0-99, a PP spunbond nonwoven is placed with an inclination of 45° on a filter paper serving as an absorption layer. The run length necessary to completely pass a defined amount of a synthetic urine solution through the fabric into the underlying absorption layer is determined. To pass the test, a maximum run length of 30 mm is allowed.
Ten Drop Test
In the ten drop test according to an in-house testing method, a 10-well metal mask is placed on a piece of nonwoven fabric as an absorption layer. Successively, one drop of a synthetic urine solution is pipetted into each well. A test field counts as passed if the amount of fluid has been absorbed by the underlying absorption layer within two seconds. To obtain a statement on the permanence of a fiber preparation, the test is repeated each time after a waiting time of 3 minutes without exchanging the absorption layer. The test result indicates the number of test fields passed.
Dry Migration
In the dry migration test according to an in-house testing method, migration of the constituents of the hydrophilic fiber preparation into the surrounding hydrophobic nonwoven material is simulated. To this end, hydrophilic and hydrophobic layers are alternately stacked and stored for 48 hours under pressure (bearing load of 10 kg) at an elevated temperature of 60° C. The hydrophobic layers of nonwoven fabric are placed in a solution of synthetic urine, and the wetting of the layers is assessed. Ideally, there is no wetting of the hydrophobic nonwoven fabric. Assessment is based on the following criteria:
Grade 1: No Wetting Visible
Grade 2: max. 5 wetting sites with a diameter of <2 mm visible
Grade 3: 6 to 15 wetting sites with a diameter of <2 mm visible
Grade 4: more than 15 wetting sites with a diameter of <2 mm visible, or wetting sites with a diameter of >2 mm visible
Wet Migration
In the wet migration test according to an in-house testing method, the detachment of a fiber preparation and its transfer from hydrophilic to hydrophobic areas in contact with a fluid are tested. To this end, a hydrophilic piece of nonwoven fabric finished with a fiber preparation is placed in a Petri dish containing synthetic urine, and a hydrophobic piece of nonwoven fabric is laid on top. After 30 seconds wetting of the hydrophobic piece of nonwoven fabric is assessed. Ideally, the hydrophobic nonwoven fabric is not hydrophilized. Assessment is made by specifying the wetted surface in percent.
The results of the tests performed with regard to the compositions according to Examples 1 and 2 and Comparative examples 1 to 6 are shown in Table 1 below, with the target values compared to the measuring values obtained in each case. The test is considered as passed if all measuring values are within the range of the target values.
Examples 1 and 2 according to the present invention containing a non-ionic surfactant together with a quaternary ammonium compound and a neutralized phosphoric acid ester mixture meet the requirements for quickly and permanently hydrophilizing the polyolefin nonwoven fabric without migration.
Comparative examples 1 to 3 and the commercially available comparative examples 4 to 6 fail to meet at least one of the desired requirements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2012 021 742.0 | Nov 2012 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2013/072678 | 10/30/2013 | WO | 00 |
