阅读说明：本技术 一种具有电磁屏蔽功能的超细纤维绒面革制造方法 (Method for manufacturing superfine fiber suede leather with electromagnetic shielding function ) 是由 范浩军 李静 向均 崔梦杰 陈意 颜俊 王丽 于 2020-07-16 设计创作，主要内容包括：本发明公开了一种具有电磁屏蔽功能的超细纤维绒面革(简称超纤绒面革)制造方法,其特征是将纳米电磁屏蔽材料(碳化钛(Ti<Sub>3</Sub>C<Sub>2</Sub>T<Sub>X</Sub>)、导电炭黑、石墨烯、碳纳米管、羰基铁、四氧化三铁)分散到溶剂型含浸聚氨酯浆料中,将浸渍有上述浆料的海岛型超纤无纺布置于凝固液中凝固,接着减量,水洗,干燥及后整理得到超纤绒面革。本技术制备的具有电磁屏蔽功能超纤绒面革,凝固过程水和溶剂交换赋予其蜂窝状结构,聚氨酯和纳米电磁屏蔽材料构成蜂窝状结构的骨架,减量过程去除海组分产生多孔结构。当电磁波进入超纤内部时,纳米电磁屏蔽材料协同多孔结构,对电磁波产生明显的损耗,在8.2~12.4GHz的高频电磁波下具有显著的屏蔽性能且屏蔽性能不随使用时间的延长而下降。(The invention discloses a method for manufacturing superfine fiber suede leather (superfine fiber suede leather for short) with electromagnetic shielding function, which is characterized in that nano electromagnetic shielding material (titanium carbide (Ti) 3 C 2 T X ) Conductive carbon black, graphene, carbon nanotubes, carbonyl iron and ferroferric oxide) into a solvent-based impregnated polyurethane slurry, arranging the island-type microfiber nonwoven impregnated with the slurry into a solidification solution for solidification, then reducing, washing with water, drying and finishing to obtain the microfiber suede leather. The superfine fiber suede leather with the electromagnetic shielding function, which is prepared by the technology, has a honeycomb structure endowed by water and solvent exchange in the solidification process, a framework of the honeycomb structure is formed by polyurethane and a nano electromagnetic shielding material, and a porous structure is generated by removing sea components in the reduction process. When electromagnetic waves enter the inside of the microfiber, the nano electromagnetic shielding material cooperates with the porous structure to generate obvious loss to the electromagnetic waves, and the loss is 8.2-12.4 GHzThe shielding performance of the electromagnetic wave at the frequency is remarkable and does not decrease along with the prolonging of the service time.)

1. A method for manufacturing superfine fiber suede leather with an electromagnetic shielding function is characterized in that the superfine fiber suede leather with the electromagnetic shielding function is endowed with a composite material honeycomb structure in the process of solidification through water and solvent exchange, polyurethane and an introduced nano electromagnetic shielding material form a framework of the honeycomb structure, sea components are removed in the process of reduction to generate a porous structure, and the superfine fiber suede leather manufactured through aftertreatment has remarkable electromagnetic shielding performance on electromagnetic waves of 8.2-12.4 GHz, and is specifically prepared through the following steps:

(1) preparing impregnated polyurethane slurry: adding 2-10% of nano electromagnetic shielding material by weight of polyurethane raw material into solvent type polyurethane resin, adding solvent, color paste and 0.5 part of foam hole regulator selected according to requirements, and uniformly dispersing the nano electromagnetic shielding material into polyurethane by means of ultrasonic-assisted stirring to obtain impregnated polyurethane slurry with the solid content of 20-25%;

(2) dipping: placing the sea-island superfine fiber non-woven fabric into the impregnated polyurethane slurry prepared in the step (1) for impregnation, then extruding by a roller, and scraping off the surface impregnation solution by a scraper;

(3) solidification, weight reduction and after-finishing: and solidifying the impregnated microfiber non-woven fabric by using a wet solidification process to form a honeycomb structure among fibers of the base fabric, performing conventional weight reduction fiber opening, washing, drying, and performing conventional after-treatment such as sanding, dyeing and the like to prepare the microfiber suede leather with the electromagnetic shielding function.

2. The method for manufacturing microfiber suede leather having electromagnetic shielding property of claim 1, wherein said nano electromagnetic shielding material is titanium carbide (Ti)₃C₂T_X) One or a combination of conductive carbon black, graphene, carbon nano tubes, carbonyl iron and ferroferric oxide.

3. The method of claim 1, wherein the sea-island type microfiber nonwoven fabric is classified into an alkali-reduced type and a toluene-reduced type according to a reduction method, and is classified into one of a PET/COPET type, PA6/COPET, PA6/PET type and PA6/PE type according to the sea-island fiber component.

4. The method for manufacturing the ultrafine fiber suede leather with the electromagnetic shielding performance of claim 1, wherein the cell regulator is one or a combination of hydrophobic surfactants containing fluorine, silicon or long-chain hydrophobic groups, which can delay the generation of a surface dense layer, so that the solvent in the membrane can diffuse for a sufficient time to generate a cellular porous structure.

5. The method of claim 1, wherein the reducing process is an alkali reducing process, the corresponding sea-island fiber is one of PET/COPET type, PA6/COPET, PA6/PET type, or toluene reducing process, and the corresponding sea-island fiber is one of fixed island and indefinite island PA6/PE type.

Technical Field

The invention relates to the field of superfine fiber synthetic leather, in particular to a method for manufacturing superfine fiber suede leather with an electromagnetic shielding function.

Background

The superfine fiber synthetic leather is a composite material developed based on dissolved sea island type superfine fibers and consists of superfine fibers and polyurethane. The superfine fiber is in a bundle shape, and the fineness and the structure are similar to those of collagen fiber. The superfine fibers are three-dimensionally crosslinked together in the superfine fiber synthetic leather and play a supporting role as a framework; the polyurethane distributed around the fiber enables the whole synthetic leather base cloth to form an organic whole, the polyurethane has filling performance in the base cloth, and forms circular, fingerprint-shaped or honeycomb-shaped cellular structures which are communicated in a staggered mode, so that the superfine fiber synthetic leather has good air permeability, moisture permeability and plumpness similar to leather. The superfine fiber synthetic leather has almost all the advantages of natural leather, is better than the natural leather in the aspects of temperature resistance, texture uniformity, mechanical strength and the like, and becomes a high-grade substitute of the natural leather.

The manufacturing technology of the superfine fiber synthetic leather in China starts late, approximately in the 90 th 20 th century, although the superfine fiber synthetic leather is developed rapidly, most of the superfine fiber synthetic leather is in a follow-up level, the homogenization is serious, and high-physical-property and functional products are still in a research and development stage. Compared with the national with technical advantages, the superfine fiber synthetic leather product in China still has certain gap, so the innovation of accelerating the manufacturing technology of the superfine fiber synthetic leather in China is imperative, and the change from the large country manufactured by the superfine fiber leather to the strong country manufactured by the superfine fiber leather in China can be promoted. Wherein the functional superfine fiber synthetic leather is expected to become the mainstream of the high-end product of the superfine fiber synthetic leather in the future.

Along with the rapid development of modern science and technology, various electronic and electrical devices greatly improve the social production efficiency and bring convenience to the life of people, meanwhile, the devices can generate electromagnetic radiation and interference in the working process, new pollution which is not easy to protect is brought to the environment of human life, even the health of people is threatened, particularly the radiation hazard of high-frequency (8.2-12.4 GHz) electromagnetic waves is larger, and the technical difficulty in researching and developing the high-frequency electromagnetic radiation prevention material is larger. Therefore, it is very important to research an efficient electromagnetic shielding material to avoid the harm of electromagnetic radiation and interference to human production and life. Chinese patent No. CN 104862986 a discloses a method for preparing a colored electromagnetic shielding fabric, which comprises coloring a textile with a chemically polymerizable organic dye, and polymerizing the dye into a conductive polymer by chemical polymerization, but the fabric only shows electromagnetic shielding performance at a lower frequency band, and the application range of the fabric is limited. Chinese patent No. CN 105219895A discloses a method for preparing leather with electromagnetic shielding property, which comprises spraying a film-forming agent on the surface of the leather, drying, then spraying a dispersion liquid containing nano metal powder on the surface of the leather, drying, finally spraying a layer of film-forming agent, and drying. However, as the nano metal powder is only sprayed on the surface of the leather, the main part of the electromagnetic shielding is the surface coating, and when the surface coating is damaged by abrasion and the like, the leather loses the electromagnetic shielding performance and does not have the durability of the electromagnetic shielding.

Disclosure of Invention

Aiming at the defects of the prior art, the invention skillfully utilizes the special wet solidification process of the microfiber synthetic leather, utilizes the characteristic that impregnated polyurethane forms a honeycomb structure after being solidified in a solidification bath, constructs a skeleton of a honeycomb hole consisting of polyurethane and a nano electromagnetic shielding material, exchanges solvent and water to form a honeycomb cellular structure, removes sea components in a decrement process to generate a microfiber suede leather composite material with a porous structure, and the microfiber suede leather prepared by post-processing has obvious electromagnetic shielding performance on high-frequency (8.2-12.4 GHz) electromagnetic waves, and is specifically prepared by the following steps:

(1) preparing impregnated polyurethane slurry: adding 2-10% of nano electromagnetic shielding material by weight of polyurethane raw material into solvent type polyurethane resin, adding solvent, color paste and 0.5 part of foam hole regulator selected according to requirements, and uniformly dispersing the nano electromagnetic shielding material in the polyurethane by means of ultrasonic-assisted stirring to obtain impregnated polyurethane slurry with the solid content of 20-25%;

(2) dipping: placing the sea-island superfine fiber non-woven fabric into the impregnated polyurethane slurry prepared in the step (1) for impregnation, then extruding by a roller, and scraping off the surface impregnation solution by a scraper;

(3) solidification, weight reduction and after-finishing: and solidifying the impregnated microfiber non-woven fabric by using a wet solidification process to form a honeycomb structure among fibers of the base fabric, then performing conventional weight reduction fiber opening, water washing, drying, and performing conventional post-processing and finishing such as sanding, dyeing and the like to prepare the microfiber suede leather with the electromagnetic shielding function.

The nano electromagnetic shielding material is titanium carbide (Ti)₃C₂T_X) One or a combination of conductive carbon black, graphene, carbon nano tubes, carbonyl iron and ferroferric oxide.

The sea-island type superfine fiber non-woven fabric is divided into an alkali-reduced type and a toluene-reduced type according to a reduction mode, and is divided into one of a PET/COPET type, a PA6/COPET type, a PA6/PET type and a PA6/PE type according to sea-island fiber components.

The foam hole regulator is one or combination of hydrophobic surfactants containing fluorine, silicon or long-chain hydrophobic groups, and can delay the generation of a surface compact layer, so that the solvent in the film has sufficient time to diffuse, and a honeycomb porous structure can be generated.

The decrement process can be an alkali decrement process, the corresponding sea-island fiber is one of PET/COPET type, PA6/COPET and PA6/PET type, or a toluene decrement process can be adopted, and the corresponding sea-island fiber is one of fixed island and indefinite island PA6/PE type.

The invention has the following beneficial effects:

1. the superfine fiber suede leather with the electromagnetic shielding function, which is prepared by the invention, adopts a wet process to introduce a nano electromagnetic shielding material into the superfine fiber to form a framework with a honeycomb structure together with polyurethane, and the honeycomb holes are one of the most effective structures for forming multiple reflection and scattering of electromagnetic waves in the superfine fiber leather; when the electromagnetic wave generates multiple reflection and scattering among the honeycomb-shaped holes, the nano electromagnetic shielding material is effectively increased to dissipate the electromagnetic wave, so that the electromagnetic shielding performance is improved, and compared with a blank sample, the electromagnetic shielding effectiveness SE can be improved by 30 times.

2. The superfine fiber suede leather with the electromagnetic shielding performance, prepared by the invention, has excellent electromagnetic shielding performance at a high frequency of 8.2-12.4 GHz, and makes up for the existing short plate of the electromagnetic shielding material.

3. The superfine fiber suede leather with the electromagnetic shielding performance, which is prepared by the invention, has the advantages that the nano electromagnetic shielding material has more excellent electromagnetic shielding performance, the nano electromagnetic shielding material is uniformly distributed from the surface to the inside, the microporous structure penetrates through the nano electromagnetic shielding material and the microporous structure, the excellent electromagnetic shielding performance is endowed to the finished leather under the synergistic effect of the nano electromagnetic shielding material and the microporous structure, the retention rate of the electromagnetic shielding performance is still over 99 percent even after a surface layer is repeatedly ground, and the lasting electromagnetic shielding performance is presented.

The specific implementation method comprises the following steps:

the present invention is described in detail below by way of examples, and it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention.