CN110195357A - A kind of micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type and its manufacturing method - Google Patents

Abstract

The present invention relates to synthetic leather production technical field, in particular to the micro-nano frothed aqueous polyurethane synthetic leather of a kind of environment-friendly type and its manufacturing method.The following steps are included: (1) using aqueous polyurethane as raw material, is foamed using micro-nano bubble generator, micro-nano frothed aqueous polyurethane A is obtained；(2) filler, colorant, crosslinking agent and thickener are added into micro-nano frothed aqueous polyurethane A, obtains micro-nano frothed aqueous polyurethane slurry B；(3) on micro-nano frothed aqueous polyurethane slurry B blade coating to base fabric, oven drying is entered back into, micro-nano frothed aqueous polyurethane bass C is obtained；(4) postfinishing process that micro-nano frothed aqueous polyurethane bass C is passed through to synthetic leather, obtains the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type.The micro-nano frothed aqueous polyurethane synthetic leather of the environment-friendly type that the present invention obtains has splendid sanitation performance and environmental-protecting performance.

Description

A kind of environment-friendly micro-nano foamed waterborne polyurethane synthetic leather and its manufacturing method

technical field

The invention relates to the technical field of synthetic leather production, in particular to an environment-friendly micro-nano foamed water-based polyurethane synthetic leather and a manufacturing method thereof.

Background technique

Synthetic leather is a composite material that simulates the structure and performance of natural leather and can be used as a substitute for natural leather. Usually non-woven fabric is used to simulate the mesh layer, and microporous polyurethane coating is used to simulate the grain layer. The front and back of the obtained synthetic leather are very similar to leather, and have a certain degree of air permeability, which is closer to natural leather than ordinary artificial leather. Widely used in making shoes, boots, bags and ball games. In 2014, the domestic consumption of synthetic leather was about 4.55 billion square meters, and its total production ranked first in the world. It is estimated that the average compound growth rate between 2015 and 2020 is about 16.3%, and the market demand in 2020 is about 585 million cubic meters.

At present, the production of polyurethane synthetic leather mainly adopts solvent-based production process, and its basic process is as follows: non-woven fabric → solvent-based polyurethane wet-process coagulation coating (bottom layer) → washing → drying → solvent-based polyurethane dry transfer film coating (upper layer). There are following major technical problems in adopting this production process. First, the solvent-based polyurethane wet-cured coating is used as the bottom layer. The wet-processed polyurethane (PU) slurry is coated on the surface of the non-woven fabric by a roller coating machine, and then "H ₂ O -DMF" coagulation bath, to solidify PU to form a film with a microporous structure. In this process, DMF (dimethylformamide) is used as a solvent, and the processing process will cause solvent pollution of DMF. Moreover, water cannot completely replace the DMF in the polyurethane, which will cause the problem of DMF residue in the product, and eventually cause product safety problems. And this kind of product safety problem will restrict products from entering the high-end market among numerous technical barriers and trade barriers. Second, the solvent-based polyurethane wet coagulation coating process requires large energy consumption for drying. At present, the energy consumption required for a production line is 115KW/hour of electricity and 700,000 kcal/hour of steam. Third, the use of solvent-based polyurethane wet coagulation coating technology requires a special DMF recovery device, which also requires high energy consumption. At present, the investment in a device for recovering 20 tons of DMF per month is about 3.5 million yuan. Fourth, use solvent-based polyurethane dry transfer film coating as the top layer. This process is to use solvent-based polyurethane slurry to coat the surface of the release paper with a scraper coater, and then combine it with a wet transfer solidified coating. The nonwoven fabric is pasted, peeled off after drying, and the polyurethane film is transferred to the surface of the wet transfer film layer to finally obtain synthetic leather. Since this process uses a solvent-based finishing system, it contains a large amount of toxic organic solvents, such as TOL (toluene), MEK (methyl ethyl ketone) and THF (tetrahydrofuran). These organic solvents are extremely volatile during the production process, seriously pollute the environment and pose a threat to the health of field operators.

According to the above-mentioned traditional solvent-based production process, there is a serious environmental pollution problem in the production process, which is a non-clean production process. DMF residues tend to occur in the obtained polyurethane synthetic leather, which is harmful to the human body. Therefore, according to the current development trend, it is an inevitable trend to study the clean production process and produce environmentally friendly polyurethane synthetic leather.

Contents of the invention

Aiming at the problems existing in the prior art, the present invention provides an environment-friendly micro-nano foamed water-based polyurethane synthetic leather and a manufacturing method thereof. The obtained synthetic leather does not contain pollutants and has good air permeability and water vapor permeability. There is no pollution in the process and the cost is low.

The present invention is achieved through the following technical solutions:

A kind of manufacture method of environment-friendly type micro-nano foamed waterborne polyurethane synthetic leather, comprises the following steps:

(1) Using water-based polyurethane as a raw material, a micro-nano bubble generator is used for foaming to obtain micro-nano foamed water-based polyurethane A;

(2) Add fillers to the micro-nano foamed water-based polyurethane A; or, add fillers to the micro-nano foamed water-based polyurethane A, and add at least one of a coloring agent, a crosslinking agent and a thickener to obtain a micro-nano Foaming water-based polyurethane slurry B;

(3) The micro-nano foamed water-based polyurethane slurry B is scraped into the base cloth and dried to obtain the micro-nano foamed water-based polyurethane base C;

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the post-finishing process of the synthetic leather to obtain an environment-friendly water-based foamed polyurethane synthetic leather.

Preferably, step (1) is specifically: passing the water-based polyurethane through the micro-nano bubble generator to form bubbles with a diameter of 150 nanometers to 4 microns in the water-based polyurethane, and controlling the number of times the water-based polyurethane passes through the micro-nano bubble generator to be 1 to 20 The second step is to obtain micro-nano foamed water-based polyurethane A with a volume content of bubbles between 10% and 300%.

Preferably, in step (1), the water-based polyurethane adopts an aqueous polyurethane dispersion with a solid content of 25% to 65%, an aqueous polyurethane emulsion with a solid content of 25% to 65%, or a water-soluble polyurethane emulsion with a solid content of 25% to 65%. Polyurethane.

Preferably, in step (1), the gas used for foaming is air, oxygen, hydrogen, ozone or carbon dioxide.

Preferably, in step (2), in terms of parts by mass, the dosage of each component is: 100 parts of micro-nano foamed water-based polyurethane A, 10-150 parts of filler, 0-5 parts of colorant, 0-2 parts of cross-linking agent and 0-2 parts of thickener.

Preferably, in step (2), the filler is calcium carbonate with a mesh number of 500-2000 mesh, talc powder with a mesh number of 500-2000 mesh or wood powder with a mesh number of 500-2000 mesh, and the colorant is water-based color paste or toner , the crosslinking agent is an aziridine type crosslinking agent or an isocyanate type crosslinking agent, and the thickener is a polyurethane type thickener, an acrylic type thickener or a cellulose type thickener.

Preferably, the step (3) is specifically: apply and scrape the micro-nano foamed water-based polyurethane slurry B on the base cloth, control the gap between the scraper and the base cloth to be between 0.1-2mm, and bake under the condition of 80-150°C Dry to obtain micro-nano foaming water-based polyurethane Bass C.

Preferably, in step (3), the base fabric is woven fabric, knitted fabric or non-woven fabric.

Preferably, in step (4), the post-finishing process of the synthetic leather includes a water-based polyurethane dry veneer process and a water-based polyurethane surface direct coating and embossing process.

The environment-friendly micro-nano foamed water-based polyurethane synthetic leather obtained by adopting the manufacturing method.

Compared with the prior art, the present invention has the following beneficial technical effects:

The invention takes water-based polyurethane micro-nano foaming technology as the core, produces micro-nano foamed water-based polyurethane Bess C, and then undergoes a finishing process of synthetic leather to obtain an environment-friendly micro-nano foamed water-based polyurethane synthetic leather. The present invention has the following advantages: First, the water-based polyurethane slurry containing micro-nano bubbles is prepared using a micro-nano bubble generator, and the environmentally friendly micro-nano foamed water-based polyurethane synthetic leather prepared thereby has good air permeability and water vapor permeability , gas permeability ≥ 12000 (ml/cm ² ·h), water vapor permeability ≥ 2.0 (mg/cm ² ·h). Its two, the environment-friendly micro-nano foamed water-based polyurethane synthetic leather that the present invention obtains fails to detect any EU high concern level substance (SVHC), has excellent hygienic performance and environmental protection performance, can satisfy various shoe-making , furniture sofa skin, car seat interior, interior decoration soft bag and other high-end application requirements. Its three, the present invention adopts environment-friendly raw material and clean production method, and production process has no pollution.

Detailed ways

The present invention will be further described in detail below in conjunction with specific embodiments, which are explanations of the present invention rather than limitations.

The manufacture method of environment-friendly micro-nano foamed water-based polyurethane synthetic leather of the present invention comprises the following steps:

(1) Using water-based polyurethane as a raw material, a micro-nano bubble generator is used for foaming to obtain micro-nano foamed water-based polyurethane A;

(2) adding a certain amount of filler, colorant, crosslinking agent and thickener to the micro-nano foamed water-based polyurethane A to obtain the micro-nano foamed water-based polyurethane slurry B;

(3) The micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, and then dried in an oven to obtain the micro-nano foamed water-based polyurethane base C;

(4) After the micro-nano foamed water-based polyurethane Beisi C is processed through the finishing process of synthetic leather, an environment-friendly micro-nano foamed water-based polyurethane synthetic leather can be obtained.

Step (1) is specifically: passing the water-based polyurethane through the micro-nano bubble generator to form bubbles with a diameter of 150 nanometers to 4 microns in the water-based polyurethane, and controlling the number of times the water-based polyurethane passes through the micro-nano bubble generator to be 1 to 20 times to obtain Micro-nano foamed water-based polyurethane A with a volume content of bubbles between 10% and 300%. The water-based polyurethane adopts water-based polyurethane dispersion with a solid content of 25% to 65%, water-based polyurethane emulsion with a solid content of 25% to 65%, or water-soluble polyurethane with a solid content of 25% to 65%. The gas used for foaming is air, oxygen, hydrogen, ozone or carbon dioxide.

In step (2), in terms of parts by mass, the dosage of each component is: 100 parts of micro-nano foamed water-based polyurethane A, 10-150 parts of filler, 0-5 parts of coloring agent, 0-2 parts of crosslinking agent and 0 parts ~2 parts thickener. The filler is calcium carbonate with a mesh number of 500-2000 mesh, talcum powder with a mesh number of 500-2000 mesh or wood powder with a mesh number of 500-2000 mesh, the colorant is water-based color paste or toner, and the cross-linking agent is aziridine A crosslinking agent or an isocyanate crosslinking agent, and the thickener is a polyurethane thickener, an acrylic thickener or a cellulose thickener.

Step (3) is specifically as follows: apply and scrape the micro-nano foamed water-based polyurethane slurry B on the base cloth, control the gap between the scraper and the base cloth to be between 0.1-2mm, and dry at 80-150°C to obtain Micro-nano foaming water-based polyurethane Bass C. The base fabric is woven, knitted or non-woven.

In step (4), the post-finishing process of the synthetic leather includes a water-based polyurethane dry veneer process and a water-based polyurethane surface direct coating and embossing process.

Example 1

(1) the water-based polyurethane is passed through the micro-nano bubble generator to form bubbles with a diameter of 150 nanometers in the water-based polyurethane, and the number of times the water-based polyurethane is controlled to pass through the micro-nano bubble generator is 5 times to obtain a bubble volume content between 30%. Micro-nano foaming water-based polyurethane A. Among them, the water-based polyurethane uses a water-based polyurethane dispersion with a solid content of 25%, and the gas used for foaming is air.

(2) Add 10 parts of calcium carbonate, 1 part of water-based color paste, 1 part of aziridine crosslinking agent and 1 part of polyurethane thickener to 100 parts of micro-nano foaming water-based polyurethane A to obtain micro-nano foaming water-based Polyurethane slurry B; the mesh number of calcium carbonate is 500 mesh.

(3) Micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, and the gap between the scraper and the base cloth is controlled at 0.1mm, and then dried in an oven at 80°C to obtain micro-nano foamed water-based polyurethane base C; the base cloth is non-woven fabric.

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the water-based polyurethane dry veneer process and the water-based polyurethane surface direct coating and embossing process to obtain environmentally friendly water-based foamed polyurethane synthetic leather.

Example 2

(1) the water-based polyurethane is passed through the micro-nano bubble generator to form bubbles with a diameter of 500 nanometers in the water-based polyurethane, and the number of times the water-based polyurethane is controlled to pass through the micro-nano bubble generator is 15 times, and the bubble volume content obtained is between 100%. Micro-nano foaming water-based polyurethane A. Among them, the water-based polyurethane uses a water-based polyurethane emulsion with a solid content of 30%, and the gas used for foaming is oxygen.

(2) Add 30 parts of talc powder and 1 part of aziridine crosslinking agent to 100 parts of micro-nano foamed water-based polyurethane A to obtain micro-nano foamed water-based polyurethane slurry B; the mesh number of calcium carbonate is 800 mesh.

(3) The micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, and the gap between the scraper and the base cloth is controlled at 0.3mm, and then dried in an oven at 80°C to obtain the micro-nano foamed water-based polyurethane base C; the base cloth is knitted fabric.

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the water-based polyurethane dry veneer process and the water-based polyurethane surface direct coating and embossing process to obtain environmentally friendly water-based foamed polyurethane synthetic leather.

Example 3

(1) The water-based polyurethane is passed through the micro-nano bubble generator to form bubbles with a diameter of 1 micron in the water-based polyurethane, and the number of times the water-based polyurethane is passed through the micro-nano bubble generator is 1 time to obtain a bubble volume content between 50%. Micro-nano foaming water-based polyurethane A. Among them, the water-based polyurethane uses a water-based polyurethane dispersion with a solid content of 35%, and the gas used for foaming is hydrogen.

(2) Add 50 parts of calcium carbonate, 3 parts of water-based color paste, 0.5 parts of aziridine crosslinking agent and 0.5 part of acrylic thickener to 100 parts of micro-nano foamed water-based polyurethane A to obtain micro-nano foamed water-based Polyurethane slurry B; the mesh number of calcium carbonate is 1000 mesh.

(3) Micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, and the gap between the scraper and the base cloth is controlled at 0.5mm, and then dried in an oven at 150°C to obtain micro-nano foamed water-based polyurethane base C; the base cloth is Woven cloth.

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the water-based polyurethane dry veneer process and the water-based polyurethane surface direct coating and embossing process to obtain environmentally friendly water-based foamed polyurethane synthetic leather.

Example 4

(1) the water-based polyurethane is passed through the micro-nano bubble generator to form bubbles with a diameter of 2 microns in the water-based polyurethane, and the number of times the water-based polyurethane is controlled to pass through the micro-nano bubble generator is 10 times, and the bubble volume content obtained is between 150%. Micro-nano foaming water-based polyurethane A. Among them, the water-based polyurethane uses a water-based polyurethane emulsion with a solid content of 50%, and the gas used for foaming is ozone.

(2) Add 100 parts of calcium carbonate, 5 parts of toner and 2 parts of cellulose thickeners to 100 parts of micro-nano foamed water-based polyurethane A to obtain micro-nano foamed water-based polyurethane slurry B; the mesh number of calcium carbonate It is 2000 mesh.

(3) The micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, and the gap between the scraper and the base cloth is controlled at 1mm, and then dried in an oven at 120°C to obtain the micro-nano foamed water-based polyurethane base C; the base cloth is without spinning.

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the water-based polyurethane dry veneer process and the water-based polyurethane surface direct coating and embossing process to obtain environmentally friendly water-based foamed polyurethane synthetic leather.

Example 5

(1) the water-based polyurethane is passed through the micro-nano bubble generator to form bubbles with a diameter of 3 microns in the water-based polyurethane, and the number of times the water-based polyurethane is controlled to pass through the micro-nano bubble generator is 20 times to obtain a bubble volume content between 300%. Micro-nano foaming water-based polyurethane A. Among them, the water-based polyurethane uses a water-based polyurethane emulsion with a solid content of 60%, and the gas used for foaming is carbon dioxide.

(2) Add 120 parts of wood powder, 5 parts of water-based color paste, 2 parts of isocyanate crosslinking agent and 2 parts of polyurethane thickener to 100 parts of micro-nano foamed water-based polyurethane A to obtain micro-nano foamed water-based polyurethane slurry Material B; the mesh number of calcium carbonate is 500 mesh.

(3) Micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, and the gap between the scraper and the base cloth is controlled at 1.5mm, and then dried in an oven at 100°C to obtain micro-nano foamed water-based polyurethane base C; the base cloth is knitted fabric.

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the water-based polyurethane dry veneer process and the water-based polyurethane surface direct coating and embossing process to obtain environmentally friendly water-based foamed polyurethane synthetic leather.

Example 6

(1) the water-based polyurethane is passed through the micro-nano bubble generator to form bubbles with a diameter of 4 microns in the water-based polyurethane, and the number of times the water-based polyurethane is controlled to pass through the micro-nano bubble generator is 15 times, and the bubble volume content obtained is between 200%. Micro-nano foaming water-based polyurethane A. Among them, the water-based polyurethane adopts water-soluble polyurethane with a solid content of 65%, and the gas used for foaming is air.

(2) Add 150 parts of calcium carbonate to 100 parts of micro-nano foamed water-based polyurethane A to obtain micro-nano foamed water-based polyurethane slurry B; the mesh number of calcium carbonate is 500 mesh.

(3) The micro-nano foamed water-based polyurethane slurry B is scraped onto the base cloth, the gap between the scraper and the base cloth is controlled at 2mm, and then dried in an oven at 90°C to obtain the micro-nano foamed water-based polyurethane base C; the base cloth is machine Weaving.

(4) The micro-nano foamed water-based polyurethane Beisi C is subjected to the water-based polyurethane dry veneer process and the water-based polyurethane surface direct coating and embossing process to obtain environmentally friendly water-based foamed polyurethane synthetic leather.

The invention takes water-based polyurethane micro-nano foaming technology as the core, produces micro-nano foamed water-based polyurethane Bess C, and then undergoes a finishing process of synthetic leather to obtain an environment-friendly micro-nano foamed water-based polyurethane synthetic leather. The environment-friendly micro-nano foamed water-based polyurethane synthetic leather obtained by the present invention fails to detect any EU substances of high concern (SVHC), air permeability ≥ 12000 (ml/cm ² h), and water vapor permeability ≥ 2.0 ( mg/cm ² ·h), has excellent hygienic performance and environmental protection performance, and can meet the needs of various high-end applications such as shoemaking, furniture sofa coverings, car seat interiors, and interior decoration soft bags.

Claims (10)

1. a kind of manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type, which comprises the following steps:

(1) it using aqueous polyurethane as raw material, is foamed using micro-nano bubble generator, obtains the poly- ammonia of micro-nano frothed aqueous Ester A；

(2) filler is added into micro-nano frothed aqueous polyurethane A；It is filled out alternatively, being added into micro-nano frothed aqueous polyurethane A At least one of material, and colorant, crosslinking agent and thickener is added, obtain micro-nano frothed aqueous polyurethane slurry B；

(3) micro-nano frothed aqueous polyurethane slurry B blade coating is dry into base fabric, obtains micro-nano frothed aqueous polyurethane shellfish This C；

(4) it is poly- to obtain environment-friendly type aqueous foaming for the postfinishing process that micro-nano frothed aqueous polyurethane bass C is passed through to synthetic leather Urethane synthetic leather.

2. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In step (1) specifically: by aqueous polyurethane by micro-nano bubble generator, forming diameter in aqueous polyurethane is 150 Nanometer~4 microns of bubble, the number that control aqueous polyurethane passes through micro-nano bubble generator are 1~20 time, obtain bubble Volume content is the micro-nano frothed aqueous polyurethane A between 10~300%.

3. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In in step (1), aqueous polyurethane uses aqueous polyurethane dispersion, solid content 25% of the solid content for 25%~65% The soluble polyurethane that~65% aqueous polyurethane emulsion or solid content is 25%~65%.

4. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In in step (1), the gas used that foams is air, oxygen, hydrogen, ozone or carbon dioxide.

5. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In, in step (2), in terms of mass fraction, dosage of each component are as follows: 100 parts of micro-nano frothed aqueous polyurethane A, 10~150 parts fill out Material, 0~5 part of colorant, 0~2 part of crosslinking agent and 0~2 part of thickener.

6. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In in step (2), filler is the talcum powder or mesh number that mesh number is the calcium carbonate of 500~2000 mesh, mesh number is 500~2000 mesh For the wood powder of 500~2000 mesh, colorant is aqueous color paste or toner, and crosslinking agent is aziridines crosslinking agent or isocyanates Class crosslinking agent, thickener are polyurethanes thickener, acrylic thickener or cellulose thickener.

7. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In step (3) specifically: scrape in base fabric micro-nano frothed aqueous polyurethane slurry B painting, control the gap of scraper and base fabric It between 0.1~2mm, is dried under conditions of 80~150 DEG C, obtains micro-nano frothed aqueous polyurethane bass C.

8. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In in step (3), base fabric is woven fabric, looped fabric or non-woven fabrics.

9. the manufacturing method of the micro-nano frothed aqueous polyurethane synthetic leather of environment-friendly type according to claim 1, feature exist In in step (4), synthetic leather postfinishing process includes that aqueous polyurethane dry process surfacing process and aqueous polyurethane surface directly apply pressure Flower process.

10. being closed using the micro-nano frothed aqueous polyurethane of environment-friendly type that the described in any item manufacturing methods of claim 1-9 obtain Finished leather.