Fine denier soft non-woven fabric and preparation method thereof

Abstract

The invention provides a fine denier soft non-woven fabric and a preparation method thereof, the fine denier soft non-woven fabric comprises an upper layer structure, a lower layer structure and a composite structure, the upper layer structure is formed by 0.2 D-0. 6D PE / PET bi-component fine denier fibers through a carding process, and the gram weight is 9-30 gsm; the bi-component fiber is of a skin-core structure, a skin layer is PE, a core layer is PET, and the melting point difference is larger than or equal to 20 DEG C; the lower layer structure is formed by a 1.2 D to 6.0 D PE / PET or PE / PP bi-component coarse denier fiber through a carding process, and the gram weight of the lower layer structure is 9 to 30 gsm; the fiber is of a concentric or eccentric structure, and the melting point difference between the skin layer and the core layer is larger than or equal to 20 DEG C; according to the composite structure, the upper layer and the lower layer form a gradient fiber layer through synchronous carding and lapping, the total gram weight is 18-60 gsm after hot air solidification, and the hot air temperature is between the melting point of the PE skin layer and the melting point of the PET / PP core layer; according to the invention, the coarse denier fibers and the fine denier fibers can be made into the laminated non-woven fabric by using a double-carding mode, so that the laminated non-woven fabric has good elasticity and high bulkiness of the coarse denier fibers and smooth hand feeling and high softness of the fine denier fibers at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of non-woven fabric preparation, in particular to a fine-denier soft non-woven fabric and a preparation method thereof. Background Art

[0002] The existing composite non-woven fabrics have the following defects:

[0003] 1. Single performance: Monofilament fiber non-woven fabrics cannot balance softness (such as fine denier below 0.8D) and bulkiness (such as thick denier above 3D);

[0004] 2. Poor interlayer bonding: Traditional multi-layer non-woven fabrics are formed step by step + adhesively compounded, resulting in a decrease in air permeability (such as Chinese Patent CN108166222A);

[0005] 3. High energy consumption: A single hot air temperature is difficult to adapt to different melting point fibers. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a fine-denier soft non-woven fabric that can realize the production of a laminated non-woven fabric from thick-denier fibers and fine-denier fibers by using a double carding method, so that it has both good elasticity and high bulkiness of thick-denier fibers and a smooth hand feeling and high softness of fine-denier fibers.

[0007] 6. The present invention is realized by the following method: A fine-denier soft non-woven fabric, characterized in that: it comprises an upper layer structure, a lower layer structure and a composite structure. The upper layer structure: is formed by 0.2D - 0.6D PE / PET bicomponent fine-denier fibers through a carding process, with a grammage of 9 - 30 gsm; the bicomponent fibers are of a skin-core structure, the skin layer is PE, the core layer is PET, and the melting point difference ≥ 20°C; the lower layer structure: is formed by 1.2D - 6.0D PE / PET or PE / PP bicomponent thick-denier fibers through a carding process, with a grammage of 9 - 30 gsm; the fibers are of a concentric or eccentric structure, and the melting point difference between the skin layer and the core layer ≥ 20°C; the composite structure: the upper layer and the lower layer form a gradient fiber layer through synchronous carding and web laying, and after hot air consolidation, the total grammage is 18 - 60 gsm, and the hot air temperature is between the melting point of the PE skin layer and the melting point of the PET / PP core layer.

[0008] Further, the mass ratio of PE to PET in the upper layer fibers is 30:70 - 70:30, and the mass ratio of PE to PET / PP in the lower layer fibers is 30:70 - 70:30.

[0009] Further, the grammage ratio of the upper layer to the lower layer is 2:1 - 1:2.

[0010] Further, the hot air temperature is 110 - 150°C, the wind speed is 0.6 - 2.5 m / s, and the consolidation time is 5 - 30 seconds.

[0011] Another object of the present invention is to provide a preparation method capable of realizing the preparation operation of fine-denier soft non-woven fabric.

[0012] A preparation method of fine-denier soft non-woven fabric comprises the following steps:

[0013] Step S1, pretreatment of fine-denier fibers: opening up PE / PET bicomponent fibers;

[0014] Step S2, pretreatment of thick-denier fibers: opening up PE / PET bicomponent fibers;

[0015] Step S3, double carding and web laying: the upper layer uses a fine carding machine with a cylinder speed of 600 - 1200 rpm, and the lower layer uses a high-speed random carding machine with a speed of 600 - 1200 rpm, and they are synchronously output to a conveyor belt to form a composite fiber web;

[0016] Step S4, gradient hot air consolidation: using a three-temperature zone hot air circulation system, the first temperature zone is 110 - 130 °C to melt the PE skin layer, the second temperature zone is 120 - 150 °C to achieve interlayer bonding, and the third temperature zone is 60 - 100 °C for shaping and cooling, to produce a hot air consolidated double-carded composite non-woven fabric with a grammage of 18 - 60 gsm.

[0017] The beneficial effects of the present invention are as follows: One layer of the present invention is an ultra-fine-denier soft fiber layer, and the other layer is a thick-denier fluffy fiber layer. The two are made into a non-woven fabric with a smooth hand feeling, skin-friendly, good resilience and high fluffiness through the double carding method; By using the double carding method, the thick-denier fibers and fine-denier fibers are made into a laminated non-woven fabric, making it have both the good elasticity and high fluffiness of thick-denier fibers and the smooth hand feeling and high softness of fine-denier fibers; The fine-denier layer intercepts micron-sized particles (PM0.3 efficiency > 98%), and the thick-denier layer reduces the air flow resistance (pressure drop reduction of 29%); Mechanical synergy: the lower-layer thick-denier fibers improve the longitudinal strength (≥25 N / 5 cm), and the upper-layer fine-denier fibers enhance the transverse flexibility (bending stiffness ≤ 3 mN·cm); The bio-based composite solution achieves a degradation rate > 70% (ASTM D6400 standard) while maintaining the strength during the service life; The double carding synchronous web laying reduces the production time by 30%, and the energy consumption < 1.2 kWh / kg (the traditional step-by-step process > 1.8 kWh / kg); The hot air three-temperature zone process makes the interlayer peel strength ≥ 1.5 N / cm (the adhesive composite process ≤ 0.8 N / cm); It supports the combination of multiple materials such as PE, PET, PP, PLA, etc., and the adjustable range of the fiber denier ratio (upper layer: lower layer) is 1:1 - 1:5. Description of the Drawings

[0018] Figure 1 It is a structural schematic diagram of the present invention.

[0019] Figure 2 It is a flowchart of the preparation method of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Example 1: Medical protective material (high air permeability + anti-seepage), medical field: replacing SMS non-woven fabric, the air permeability is increased by 45%.

[0022] upper layer:

[0023] Fiber type: 0.4D PE / PET bicomponent (skin layer PE 50%, core layer PET 50%)

[0024] Gramweight:12gsm.

[0025] Carding parameters: cylinder speed 1000rpm, doffer gap 0.15mm

[0026] Lower level:

[0027] Fiber type: 2.0D PE / PP eccentric core structure (skin layer PE 60%, core layer PP 40%)

[0028] Gram Weight:18gsm.

[0029] Carding parameters: cylinder speed 500rpm, disorder ratio 30%.

[0030] Hot air consolidation:

[0031] Three temperature zones: 125°C (melting zone) → 140°C (combining zone) → 90°C (forming zone)

[0032] Wind speed: 5m / s, consolidation time 20 seconds.

[0033] Example 2: High efficiency filter material (gradient interception); Industrial filtration: life extended to 600 hours (400 hours for traditional meltblown cloth).

[0034] upper layer:

[0035] Fiber type: 0.3D PE / PET (PE 40%, PET 60%), weight 10gsm.

[0036] Pretreatment: Add 1% nano-SiO2 electret masterbatch to enhance electrostatic adsorption.

[0037] Lower level:

[0038] Fiber type: 4.0D PE / PET core (PE 70%, PET 30%), weight 20gsm

[0039] Process improvement: infrared radiation assisted heating (wavelength 3μm, power 2kW / m 2 ).

[0040] Hot air parameters: 130°C / 150°C / 100°C, wind speed 6 m / s.

[0041] Example 3: Agricultural mulch film (high strength + controllable degradation); Agricultural environmental protection: The comprehensive cost of degradable mulch film is reduced by 25%.

[0042] Upper layer:

[0043] Fiber type: 0.6D PLA / PBAT bicomponent (bio-based material), grammage 15 gsm.

[0044] Modification: Adding 2% nano-montmorillonite to improve UV stability.

[0045] Lower layer:

[0046] Fiber type: 6.0D PE / starch composite fiber (PE 50%, starch 30%, calcium carbonate 20%), grammage 25 gsm

[0047] Hot air parameters:

[0048] Temperature: PLA / PBAT layer: 160°C → PE / starch layer: 140°C → setting area: 110°C.

[0049]

[0050] As can be seen from the above table, by using the carding method, the coarse denier fibers and fine denier fibers are made into a laminated non-woven fabric, so that it has both the good elasticity and high bulkiness of the coarse denier fibers and the smooth hand feeling and high softness of the fine denier fibers.

[0051] The above are only the preferred embodiments of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope covered by the present invention.

Claims

1. A fine denier soft nonwoven fabric, characterized in that: The invention comprises an upper structure, a lower structure and a composite structure, wherein the upper structure is formed by a combing process of 0.2D-0.6D PE / PET bicomponent fine denier fibers, with a gram weight of 9-30gsm; the bicomponent fibers are of a skin-core structure, with the skin layer being PE and the core layer being PET, and the melting point difference being ≥20°C; the lower structure is formed by a combing process of 1.2D-6.0D PE / PET or PE / PP bicomponent coarse denier fibers, with a gram weight of 9-30gsm; the fibers are of a co-core or eccentric core structure, and the melting point difference between the skin layer and the core layer is ≥20°C; the composite structure comprises an upper layer and a lower layer formed by synchronous combing and laying to form a gradient fiber layer, and the total gram weight is 18-60gsm after hot air consolidation, and the hot air temperature is between the melting point of the PE skin layer and the melting point of the PET / PP core layer.

2. The fine denier soft nonwoven fabric according to claim 1, characterized in that: The mass ratio of PE to PET in the upper fiber layer is 30:70 to 70:30, and the mass ratio of PE to PET / PP in the lower fiber layer is 30:70 to 70:

30.

3. The fine denier soft nonwoven fabric according to claim 1, characterized in that: The weight ratio of the upper layer to the lower layer is 2:1 to 1:

2.

4. The fine denier soft nonwoven fabric according to claim 1, characterized in that: The hot air temperature is 110-150°C, the wind speed is 0.6-2.5 m / s, and the consolidation time is 5-30 seconds.

5. A method for preparing the fine denier soft nonwoven fabric as claimed in claim 1, characterized in that: The following steps are involved: Step S1, fine denier fiber pretreatment: opening the PE / PET bicomponent fiber; Step S2, coarse denier fiber pretreatment: opening the PE / PET bicomponent fiber; Step S3, double combing web laying: the upper layer adopts a fine combing machine with a cylinder speed of 600-1200rpm, and the lower layer adopts a high-speed random combing machine with a speed of 600-1200rpm, and outputs them to the conveyor belt synchronously to form a composite fiber web; Step S4, gradient hot air consolidation: a three-temperature zone hot air circulation system is used, the first temperature zone is 110-130°C to melt the PE cortex, the second temperature zone is 120-150°C to achieve interlayer bonding, and the third temperature zone is 60-100°C for shaping and cooling to produce a hot air consolidated double-combed composite non-woven fabric with a gram weight of 18-60gsm.

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