CN117084868A

CN117084868A - Composite structure spunlaced nonwoven fabric for paper diaper surface layer and preparation method thereof

Info

Publication number: CN117084868A
Application number: CN202311083826.4A
Authority: CN
Inventors: 朱宏伟; 乔国华; 高扬; 赵柳涛; 魏琦; 杨仕奇
Original assignee: Zhejiang Wangjin Nonwovens Co ltd
Current assignee: Zhejiang Wangjin Nonwovens Co ltd
Priority date: 2023-08-28
Filing date: 2023-08-28
Publication date: 2023-11-21

Abstract

The invention provides a composite structure spunlaced non-woven fabric for a paper diaper surface layer and a preparation method thereof, wherein the composite structure spunlaced non-woven fabric comprises a first fiber web layer and a second fiber web layer which are hydraulically entangled, the first fiber web layer comprises polyester fibers and first modified viscose fibers, the second fiber web layer comprises second modified viscose fibers and kapok fibers, a modifier of the first modified viscose fibers is an alkyl silane coupling agent, and a modifier of the second modified viscose fibers is a quaternary ammonium salt silane coupling agent; the dosage of the alkyl silane coupling agent in the first modified viscose is 10-20wt% of the viscose, and the dosage of the quaternary ammonium salt silane coupling agent in the second modified viscose is 1-5wt% of the viscose. The non-woven fabric prepared by taking the first modified viscose fiber and the polyester fiber as a first fiber layer net and taking the second modified viscose fiber and the kapok fiber as a second fiber layer net is not easy to rewet, hydrophilic and not water-absorbing, and can be used for rapidly permeating water.

Description

Composite structure spunlaced nonwoven fabric for paper diaper surface layer and preparation method thereof

Technical Field

The invention belongs to the technical field of non-woven fabrics, and particularly relates to a composite structure spunlaced non-woven fabric for a paper diaper surface layer and a preparation method thereof.

Background

Since the 21 st century, the production technology and application of disposable sanitary materials in China have been greatly developed, the consumption demands are continuously increased, and the equipment manufacture, raw material production and product processing form a complete supply chain system, wherein the production and application of non-woven fabrics are particularly prominent. The non-woven fabric has wide application range, including aerospace, agriculture, medical security, daily necessities and other fields. The most common daily life is that the disposable sanitary materials such as paper diapers, sanitary napkins, pads and the like are made of non-woven fabrics.

The non-woven fabric is mainly used in the surface layer of the absorbent products such as paper diapers, sanitary napkins, pads and the like, and has the function of being used as a separation and filtering material, so that a clean isolation layer is arranged between the skin of a human body and a liquid storage layer, and meanwhile, when liquid is discharged, the liquid can smoothly enter the liquid storage layer through the surface layer. As disclosed in patent CN201361291Y, a completely biodegradable diaper cover material is formed by combining upper and lower webs, wherein the upper web has large pores and the lower web has small pores, so that the shape of the pores formed along the thickness direction is tapered, and a gradient structure with large upper and small lower is formed. The upper layer fiber web is a polylactic acid bi-component fiber web, and the lower layer fiber web is a kapok fiber web. The linear density of the polylactic acid bicomponent fiber of the upper layer fiber web is 2.2-6.6 dtex, and the length is 38-65 mm. The kapok fiber of the lower fiber net has the length of 16-30 mm and the average linear density of 0.9-1.2 dtex. Patent CN113151977B discloses a super-soft anti-reverse osmosis kapok diaper material and a preparation method thereof, wherein the material is formed by compounding two fiber nets with different gradients and different apertures, one surface layer is a kapok/viscose water-jet fiber net, and the other two absorption layers are viscose/wood pulp wet fiber nets; the preparation method comprises the following steps: (1) preliminarily preparing a uniform kapok/viscose spunlaced fiber web by adopting a spunlaced process; (2) adopting a wet-process net-forming process, and forming a net through inclined net to obtain an viscose/wood pulp wet-process fiber net; (3) the viscose/wood pulp wet fiber web output from the inclined web and the kapok/viscose spunlaced fiber web output from the lower web are compounded by flat web and drum spunlaced; (4) drying the composite fiber web by a drying cylinder and hot air in a combined way, and dehydrating to obtain the super-soft anti-reverse osmosis kapok diaper material.

The surface layer is soft, non-irritating and has certain water permeability when contacting with human skin, and an isolation barrier is formed between the skin and the liquid storage layer, but the surface layer made of the fiber has high hydroxyl content on the surface, so that the surface layer made of the fiber is easy to permeate back, has high moisture regain, and even has certain water absorbability, so that the time for liquid to permeate into the liquid storage layer downwards through the surface layer is long, and the liquid can generate larger moisture regain due to external force.

Therefore, there is a need for a nonwoven fabric that is less prone to rewet, is hydrophilic but does not absorb water, and has good water permeability and allows for the smooth transfer of liquid through the layer to be stored.

Disclosure of Invention

In order to solve the technical problems, the invention provides the composite structure spunlaced nonwoven fabric for the surface layer of the paper diaper and the preparation method thereof, wherein silane coupling agents with different dosages are used as modifiers to carry out hydrophobic modification on viscose fibers with different degrees, the hydroxyl number and the distribution density on the surface of the viscose fibers are reduced to improve the water absorption of the viscose fibers, hydrophobic first modified viscose fibers and second modified viscose fibers with reduced water absorption are respectively obtained, the first modified viscose fibers are matched with polyester fibers to be used as a first fiber layer net, the second modified viscose fibers are matched with kapok fibers to be used as a second fiber layer net, and the nonwoven fabric obtained by compounding the first fiber layer net and the second fiber layer net through a spunlaced process is not easy to be permeated, hydrophilic but not water-absorbing, and can be used for rapidly permeating water, so that the composite structure is particularly suitable for the surface layer of the paper diaper.

In order to achieve the above purpose, the invention adopts the following technical scheme:

the composite structure spunlaced nonwoven fabric for the surface layer of the paper diaper comprises a first fiber web layer and a second fiber web layer which are hydraulically entangled, wherein the first fiber web layer comprises polyester fibers and first modified viscose fibers, the second fiber web layer comprises second modified viscose fibers and kapok fibers, the modifier of the first modified viscose fibers is an alkylsilane coupling agent, and the modifier of the second modified viscose fibers is a quaternary ammonium salt silane coupling agent; the dosage of the alkyl silane coupling agent in the first modified viscose is 10-20wt% of the viscose, and the dosage of the quaternary ammonium salt silane coupling agent in the second modified viscose is 1-5wt% of the viscose.

Preferably, the usage amount of the alkyl silane coupling agent in the first modified viscose is 10-15wt% of the viscose, and the usage amount of the quaternary ammonium salt silane coupling agent in the second modified viscose is 3-5wt% of the viscose.

Further, the mass ratio of the polyester fibers to the first modified viscose fibers in the first fiber web layer is 100:15-20; the mass ratio of the second modified viscose fiber to the kapok fiber in the second fiber web layer is 50-70:30-50.

The alkyl silane coupling agent is selected from one or a combination of two or more of octyl trimethoxy silane, n-decyl trimethoxy silane, butyl trimethoxy silane, ethyl trimethoxy silane, methyl trimethoxy silane and propyl trimethoxy silane.

The quaternary ammonium salt silane coupling agent is selected from one or a combination of two or more of dimethyl octadecyl [3- (trimethoxy silicon base) propyl ] ammonium chloride, 2-methacryloxyethyl trimethyl ammonium chloride and 4-vinylbenzyl dimethyl- (3-trimethoxy silicon propyl) ammonium chloride.

The first and modified viscose fibers are prepared by a method comprising the following steps:

adding the alcohol-water mixed solution into a reaction kettle, regulating the pH value, adding an alkyl silane coupling agent for hydrolysis to obtain a hydrolysate, immersing viscose fibers into the hydrolysate, heating and keeping the temperature for reaction for 1-3h, turning over for 15-20min for one time, filtering, washing and drying; the alkylsilane coupling agent is used in an amount of 10 to 20 wt.%, preferably 10 to 15 wt.% of the viscose fiber.

The second modified viscose fiber is prepared by a method comprising the following steps:

adding the alcohol-water mixed solution into a reaction kettle, regulating the pH value, adding a quaternary ammonium salt silane coupling agent for hydrolysis to obtain hydrolysis liquid, immersing viscose fibers into the hydrolysis liquid, heating and keeping the temperature for reaction for 1-3h, turning over for 15-20min for one time, filtering, washing and drying; the amount of the quaternary ammonium salt silane coupling agent is 1-5wt%, preferably 3-5wt% of the viscose fiber.

The mass concentration of water in the alcohol-water mixed solution is 80-95%; the alcohol is selected from one or a combination of methanol and ethanol, the pH is regulated to 4.5-5.5, the hydrolysis time is 3-10min, the temperature is raised to 50-60 ℃, the reaction time after the temperature is raised is 0.5-2h, and the drying is carried out in an oven at 100-120 ℃ for 10-30min.

The first modified viscose is prepared by modifying viscose with an excessive amount of alkyl silane coupling agent, and the excessive alkyl silane coupling agent forms a firm organic silicon film on the surface of the viscose, so that liquid can enter the second fiber web layer from the first fiber web layer, and the touch feeling of the non-woven fabric is comfortable.

The second modified viscose fiber is prepared by using a small amount of quaternary ammonium salt silane coupling agent as a modifier to modify viscose fiber, a small amount of modifier is hydrolyzed to generate silanol, the silanol reacts with hydroxyl on the surface of the viscose fiber to obtain the second modified viscose fiber with the surface bonded with the silane coupling agent, particularly the quaternary ammonium salt cation of the quaternary ammonium salt silane coupling agent has good hydrophilicity and long hydrophobic carbon chain alkyl, and the second modified viscose fiber is easier to stretch into water, so that small water drops adsorbed on the surface of the fiber are not easy to combine into large water drops, and the non-woven fabric using the small water drops as raw materials is not easy to generate rewet when the non-woven fabric is subjected to external force.

The first and second fiber web layers have an areal density of 15-30g/m ² The surface density of the composite structure spunlaced non-woven fabric for the paper diaper surface layer is 30-50g/m ² 。

The titer of the viscose fiber is 1-1.5dtex, and the length is 30-40mm; the titer of the kapok fiber is 1-1.5dtex, and the length is 15-30mm; the titer of the polyester fiber is 1-2dtex, and the length is 30-40mm.

The cross section of the polyester fiber is one of cross, round, triangle and I shape.

The invention also provides a preparation method of the composite structure spunlaced non-woven fabric for the paper diaper surface layer, which comprises the following steps:

4) Respectively opening, mixing and carding the polyester fibers and the first modified viscose fibers to form a first fiber web;

5) Respectively opening, mixing and carding the second modified viscose fiber and kapok fiber to form a second fiber web;

6) And compounding the first fiber web and the second fiber web, and carrying out hydroentanglement reinforcement, drying and rolling to obtain the composite structure hydroentangled non-woven fabric for the paper diaper surface layer.

The compound mode in the step 3) is selected from one of cross lapping and parallel lapping, the water jet pressure is 4-10MPa, and the number of water jet channels is 3-7 channels.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, different doses of alkyl or quaternary ammonium salt silane coupling agents are used as modifiers to carry out hydrophobic modification on viscose fibers to different degrees, the hydroxyl number and distribution density on the surface of the viscose fibers are reduced to improve the water absorbability of the viscose fibers, so that hydrophobic first modified viscose fibers and second modified viscose fibers with reduced water absorbability are respectively obtained, and the nonwoven fabric prepared by the first modified viscose fibers, the polyester fibers and the kapok fibers are used as a first fiber layer network, and the second modified viscose fibers and the polyester fibers are used as a second fiber layer network is not easy to rewet, hydrophilic but not water absorbability, and can be used for rapidly permeating water.

Detailed Description

The invention is further illustrated below in connection with specific examples, but is not limited to the disclosure. Unless otherwise specified, "parts" are parts by weight in the examples of the present invention. All reagents used are those commercially available in the art.

Viscose was purchased from lanin (nanjing) fiber limited with a titre of 1.67dtex and a length of 38mm;

the polyester fiber is purchased from medium petrochemical industry, YZ310 polyester staple fiber, the fineness is 1.56dtex, and the length is 38mm;

kapok fiber was purchased from Shanghai Pan major industries (group) Co., ltd. With a fineness of 1.44dtex and a length of 26mm.

Preparation of first modified viscose

Preparation example a1

Mixing 90 parts of water and 10 parts of ethanol uniformly, adding acetic acid to adjust the pH value to 5, adding 5 parts of octyl trimethoxy silane for hydrolysis for 5min to obtain hydrolysis liquid, immersing 33.5 parts of viscose fiber into the hydrolysis liquid, heating to 60 ℃ and reacting at constant temperature for 3h, turning over the surface for 15min, filtering, washing with water for 3 times, and drying in a baking oven at 120 ℃ for 10min.

Preparation example a2

The rest was the same as in preparation example a1, except that 50 parts of viscose fiber was immersed in the hydrolysis liquid.

Comparative preparation a1

The remainder was the same as in preparation example a1 except that 5 parts of dimethyloctadecyl [3- (trimethoxysilyl) propyl ] ammonium chloride was replaced with 5 parts of dimethyloctadecyl [3- (trimethoxysilyl) propyl ] ammonium chloride.

Comparative preparation a2

The rest was the same as in preparation example a1, except that 62.5 parts of viscose fiber was immersed in the hydrolysis liquid.

Preparation of second modified viscose fiber

Preparation example b1

Mixing 90 parts of water and 10 parts of ethanol uniformly, adding acetic acid to adjust the pH value to 5, adding 5 parts of dimethyl octadecyl [3- (trimethoxy silicon-based) propyl ] ammonium chloride to hydrolyze for 5min to obtain hydrolysis liquid, immersing 100 parts of viscose fiber into the hydrolysis liquid, heating to 60 ℃ and reacting for 3h at constant temperature, turning over for 15min, filtering, washing with water for 3 times, and drying in a baking oven at 120 ℃ for 10min.

Preparation example b2

Mixing 90 parts of water and 10 parts of ethanol uniformly, adding acetic acid to adjust the pH value to 5, adding 3 parts of dimethyl octadecyl [3- (trimethoxy silicon-based) propyl ] ammonium chloride to hydrolyze for 5min to obtain hydrolysis liquid, immersing 100 parts of viscose fiber into the hydrolysis liquid, heating to 60 ℃ and reacting for 3h at constant temperature, turning over for 15min, filtering, washing with water for 3 times, and drying in a baking oven at 120 ℃ for 10min.

Comparative preparation b1

The remainder was the same as in preparation example b1 except that 5 parts of dimethyloctadecyl [3- (trimethoxysilyl) propyl ] ammonium chloride was replaced with 5 parts of octyltrimethoxysilane.

Comparative preparation b2

The remainder was the same as in preparation example b1 except that 8 parts of dimethyloctadecyl [3- (trimethoxysilyl) propyl ] ammonium chloride was added.

Composite structure spunlaced nonwoven fabric for preparing paper diaper surface layer

Example 1

1) Respectively opening, mixing and carding 100 parts of polyester fibers and 20 parts of the first modified viscose fibers prepared in the preparation example a1 to form a first fiber web;

2) Respectively opening, mixing and carding 70 parts of the second modified viscose fiber prepared in the preparation example b1 and 30 parts of kapok fiber to form a second fiber web;

3) And (3) cross-lapping and compounding the first fiber web and the second fiber web, strengthening by 3 times of hydroentanglement, wherein the pressure intensity of the first time of hydroentanglement is 4.5MPa, the pressure intensity of the second time of hydroentanglement is 7.5MPa, the pressure intensity of the third time of hydroentanglement is 4.5MPa, and then drying and rolling to obtain the composite structure hydroentangled non-woven fabric for the paper diaper surface layer.

Example 2

The rest is the same as in example 1, except that the first modified viscose fibers of step 1) are prepared in accordance with the preparation example a2, respectively.

Example 3

The remainder is the same as in example 1, except that step 2) the second modified viscose fibers were prepared in accordance with preparation example b2, respectively.

Example 4

The remainder is the same as in example 1, except that the amount of the first modified viscose fiber in step 1) is 15 parts.

Example 5

The remainder was the same as in example 1, except that the second modified viscose fiber in step 2) was used in an amount of 50 parts and the kapok fiber was used in an amount of 50 parts.

Comparative example 1

The remainder is the same as in example 1, except that step 1) the first modified viscose fiber was prepared in comparative preparation a 1.

Comparative example 2

The remainder is the same as in example 1, except that step 2) a second modified viscose fiber was prepared in comparative preparation b 1.

Comparative example 3

The remainder is the same as in example 1, except that step 1) the first modified viscose fiber was prepared in comparative preparation a 2.

Comparative example 4

The remainder is the same as in example 1, except that step 2) a second modified viscose fiber was prepared in comparative preparation b 2.

The nonwoven fabrics of the above examples and comparative examples were subjected to the following performance tests:

liquid penetration time: the measurements were made with reference to the standard GB/T24218 textile-nonwoven test method.

Moisture regain: the measurements were made with reference to the standard GB/T24218 textile-nonwoven test method.

Water absorption resistance: the water absorption is tested by referring to the standard GB/T23320-2009 textile-determination of anti-water absorption-turnover absorption method, and the smaller the water absorption, the better the anti-water absorption.

TABLE 1

Project	Time of penetration of liquid s	Moisture regain g	Water absorption%
				Example 1	1.24	3.3	8.6
Example 2	1.26	3.4	8.8
				Example 3	1.75	3.7	9.1
Example 4	1.58	3.9	8.8
				Example 5	1.72	4.2	9.3
Comparative example 1	2.17	5.3	10.5
				Comparative example 2	3.97	4.5	7.5
Comparative example 3	5.21	6.6	11.9
				Comparative example 4	2.88	4.8	7.7

As can be seen from Table 1, the nonwoven fabric prepared by the present invention is not liable to rewet, has a small rewet amount, is hydrophilic but does not absorb water, and is capable of rapidly transmitting water.

The foregoing detailed description is directed to one of the possible embodiments of the present invention, which is not intended to limit the scope of the invention, but is to be accorded the full scope of all such equivalents and modifications so as not to depart from the scope of the invention.

Claims

1. The composite structure spunlaced nonwoven fabric for the surface layer of the paper diaper comprises a first fiber web layer and a second fiber web layer which are hydraulically entangled, and is characterized in that the first fiber web layer comprises polyester fibers and first modified viscose fibers, the second fiber web layer comprises second modified viscose fibers and kapok fibers, the modifier of the first modified viscose fibers is an alkylsilane coupling agent, and the modifier of the second modified viscose fibers is a quaternary ammonium salt silane coupling agent; the dosage of the alkyl silane coupling agent in the first modified viscose is 10-20wt% of the viscose, and the dosage of the quaternary ammonium salt silane coupling agent in the second modified viscose is 1-5wt% of the viscose.

2. The composite structure spunlaced nonwoven fabric for the surface layer of the diaper according to claim 1, wherein the amount of the alkylsilane coupling agent in the first modified viscose is 10-15wt% of the viscose, and the amount of the quaternary ammonium salt silane coupling agent in the second modified viscose is 3-5wt% of the viscose.

3. The composite structure spunlaced nonwoven fabric for the surface layer of the diaper according to claim 1, wherein the mass ratio of the polyester fibers to the first modified viscose fibers in the first fiber web layer is 100:15-20; the mass ratio of the second modified viscose fiber to the kapok fiber in the second fiber web layer is 50-70:30-50.

4. The composite structure spunlaced nonwoven fabric for the surface layer of a diaper according to claim 1, wherein the alkylsilane coupling agent is one or a combination of two or more selected from octyl trimethoxy silane, n-decyl trimethoxy silane, butyl trimethoxy silane, ethyl trimethoxy silane, methyl trimethoxy silane and propyl trimethoxy silane.

5. The composite structure spunlaced nonwoven fabric for the surface layer of a diaper according to claim 1, wherein the quaternary ammonium salt silane coupling agent is selected from one or a combination of two or more of dimethyl octadecyl [3- (trimethoxysilyl) propyl ] ammonium chloride, 2-methacryloxyethyl trimethyl ammonium chloride and 4-vinylbenzyl dimethyl- (3-trimethoxysilylpropyl) ammonium chloride.

6. The composite structure spunlaced nonwoven fabric for the surface layer of a diaper according to claim 1, wherein the first and modified viscose fibers are prepared by a method comprising the following steps:

adding the alcohol-water mixed solution into a reaction kettle, regulating the pH value, adding an alkyl silane coupling agent for hydrolysis to obtain a hydrolysate, immersing viscose fibers into the hydrolysate, heating and keeping the temperature for reaction for 1-3h, turning over for 15-20min for one time, filtering, washing and drying; the usage amount of the alkylsilane coupling agent is 10-20wt% of the viscose fiber, preferably 10-15wt%;

7. The composite structure spunlaced nonwoven fabric for the surface layer of a diaper according to claim 1, wherein the surface density of the first and the second fiber web layers is 15-30g/m ² The surface density of the composite structure spunlaced non-woven fabric for the paper diaper surface layer is 30-50g/m ² 。

8. The composite structure spunlaced nonwoven fabric for the surface layer of a diaper according to claim 1, wherein the titer of the viscose fiber is 1-1.5dtex and the length is 30-40mm; the titer of the kapok fiber is 1-1.5dtex, and the length is 15-30mm; the titer of the polyester fiber is 1-2dtex, and the length is 30-40mm.

9. The composite structure spunlaced nonwoven fabric for the surface layer of a diaper according to claim 1, wherein the cross-sectional shape of the polyester fiber is selected from one of cross, circular, triangular and I-shaped.

10. The method for producing a composite structure spunlaced nonwoven fabric for a surface layer of a diaper according to any one of claims 1 to 9, comprising the steps of:

1) Respectively opening, mixing and carding the polyester fibers and the first modified viscose fibers to form a first fiber web;

2) Respectively opening, mixing and carding the second modified viscose fiber and kapok fiber to form a second fiber web;

3) And compounding the first fiber web and the second fiber web, and carrying out hydroentanglement reinforcement, drying and rolling to obtain the composite structure hydroentangled non-woven fabric for the paper diaper surface layer.