Polyurethane synthetic leather capable of realizing electroluminescent display and preparation method thereof

Abstract

The invention relates to polyurethane synthetic leather capable of realizing electroluminescent display and a preparation method of the polyurethane synthetic leather. The polyurethane synthetic leather comprises a polyurethane surface layer, a top transparent electrode layer, a luminescent layer, a dielectric layer, a bottom electrode layer, an adhesive layer and a synthetic leather base material layer which are sequentially stacked, the polyurethane surface layer, the luminous layer, the dielectric layer and the adhesive layer all comprise waterborne polyurethane resin, and the waterborne polyurethane resin comprises the following components: 90-100 parts of waterborne polyurethane, 0.01-0.03 part of a polyether modified siloxane wetting agent, 0.01-0.02 part of an organic silicon defoaming agent and 3-5 parts of a polyurethane associated thickening agent. The polyurethane synthetic leather can be prepared by adopting a traditional water-based synthetic leather production line, and the prepared polyurethane synthetic leather is safe and environment-friendly by optimizing a coating formula of each layer and controlling process parameters such as drying temperature, time and the like, and is high in interlayer binding force, good in wear resistance and bending resistance, high in water resistance and high in water resistance. And after thousands of times of bending and thousands of times of friction, good luminescence performance can still be maintained.

Description

Technical Field

[0001] The invention relates to the technical field of electroluminescent devices and synthetic leather preparation, and in particular to polyurethane synthetic leather capable of electroluminescent display and a preparation method thereof. Background Art

[0002] As an artificial synthetic material, polyurethane synthetic leather has excellent properties such as soft and natural luster, strong leather appearance, wear resistance, flex resistance, and aging resistance. It also has the advantages of good cold resistance, breathability, and low price. It is an ideal substitute for natural leather. Polyurethane synthetic leather can meet the special requirements of different industries for material properties. It has been widely used in many fields such as automotive interiors, home decoration, seat fabrics, shoes, bags, clothing accessories, and sports equipment. With the continuous development of science and technology and the improvement of people's quality of life, the optimization and improvement of basic physical properties can no longer meet market demand. Consumers want to have high physical properties of synthetic leather, and at the same time, they also have higher requirements for its functionality and visual diversity. Therefore, the development of new synthetic leather varieties with innovative functions such as electroluminescence is of great significance to enhance the market competitiveness of leather products and broaden their application areas.

[0003] Patent CN210501692U discloses a microfiber leather with a luminous effect, comprising a base fabric, an antibacterial fabric arranged on the base fabric, a plurality of LED light strips arranged on the antibacterial fabric, a fluorescent cover arranged on each light chip on the LED light strip, a light sensor arranged on the side between the base fabric and the antibacterial fabric, a wire connecting the plurality of light chips in series and then connected to the light sensor, a waterproof and breathable fabric arranged on the plurality of LED light strips, the fluorescent cover passing through the waterproof and breathable fabric, and a microfiber leather arranged on the waterproof and breathable fabric, thereby achieving the effect of leather luminescence. As a result, the preparation of this type of luminous leather is not only cumbersome and unsuitable for industrial production, but also has the following limitations: (1) LED-based luminous leather can only achieve dot-matrix luminescence, and it is difficult to achieve large-area, fine-pattern luminescence; (2) Leather is a soft substrate, but hard electronic components such as LED light strips and their connecting wires usually have poor fatigue resistance and flexibility, and are prone to foreign body sensation, making it difficult to meet the requirements for flexibility and touch when leather is used as a wearable fabric for clothing, etc., and the device is easily damaged when subjected to external forces such as bending, folding, pulling, and friction.

[0004] Based on this, how to achieve leather that can emit light over a large area and always maintain good luminescence performance under the action of external forces is of great significance to broadening the application of leather. Summary of the invention

[0005] In order to solve the problems that it is difficult for current luminous leather to achieve large-area, fine-pattern luminescence and the luminescent performance is easily damaged during the use of the leather, the present invention provides a polyurethane synthetic leather capable of electroluminescent display and a preparation method thereof, which can be prepared using a traditional water-based synthetic leather production line. The prepared polyurethane synthetic leather is not only safe and environmentally friendly, but also has high interlayer bonding strength, good wear resistance and bending resistance, and can still maintain luminescent performance after thousands of bends and tens of thousands of frictions, and has good application prospects in the field of electroluminescence.

[0006] Specifically, the present invention provides the following technical solutions:

[0007] The first aspect of the present invention provides a polyurethane synthetic leather capable of electroluminescent display, the polyurethane synthetic leather comprising a polyurethane surface layer, a top transparent electrode layer, a light-emitting layer, a dielectric layer, a bottom electrode layer, an adhesive layer and a synthetic leather substrate layer stacked in sequence;

[0008] Wherein, the polyurethane surface layer, the light-emitting layer, the dielectric layer and the adhesive layer all contain water-based polyurethane resin.

[0009] Furthermore, the polyurethane surface layer is a water-based polyurethane resin layer, the luminescent layer is a water-based polyurethane resin layer containing electroluminescent powder, the dielectric layer is a water-based polyurethane resin layer containing dielectric medium material, and the adhesive layer is a water-based polyurethane resin layer.

[0010] Further, the waterborne polyurethane resin comprises the following components in parts by mass: 90-100 parts of waterborne polyurethane, 0.01-0.03 parts of polyether-modified siloxane wetting agent, 0.01-0.02 parts of silicone defoaming agent, and 3-5 parts of polyurethane associative thickener; more preferably, the waterborne polyurethane is an aliphatic polyester type and / or polyether type anionic waterborne polyurethane. The waterborne polyurethane is an aliphatic polyester type and / or polyether type anionic waterborne polyurethane, and the slurry forming the light-emitting layer and the slurry forming the dielectric layer also contain an aziridine crosslinking agent.

[0011] The polyurethane synthetic leather capable of electroluminescent display provided by the present invention, the other functional layers except the electrode layer are all waterborne polyurethane layers containing various functional materials, the formed polyurethane synthetic leather is soft in texture, safe and environmentally friendly, the luminous area and pattern can be regulated by regulating the area and pattern coated by the luminescent layer, and the bonding force between the functional layers is strong, and good luminous performance can be always maintained during long-term use or under the action of external forces. In order to further improve the structural stability of the polyurethane synthetic leather, the present invention adopts aliphatic polyester type and / or polyether type anionic waterborne polyurethane, and introduces aziridine crosslinking agent into the slurry forming the luminescent layer and the slurry forming the dielectric layer, under the action of aziridine crosslinking agent, aliphatic polyester type and / or polyether type anionic waterborne polyurethane in the luminescent layer (slurry infiltrating the top transparent electrode layer) can be crosslinked with the waterborne polyurethane in the polyurethane surface layer by aziridine crosslinking agent, and the luminescent layer and the dielectric layer and the dielectric layer and the adhesive layer can also form a chemical crosslinking structure by aziridine crosslinking agent, further improving the bonding force between the layers of the polyurethane synthetic leather, thereby effectively improving the stability of the luminous performance of the polyurethane synthetic leather during use or under the action of external forces.

[0012] The second aspect of the present invention provides a method for preparing the polyurethane synthetic leather capable of electroluminescent display according to the first aspect, comprising the following steps:

[0013] S1, coating the surface of the release paper with a water-based polyurethane resin to form a first coating, and performing a first drying treatment to obtain a polyurethane surface layer;

[0014] S2, coating the top transparent electrode layer slurry on the side of the polyurethane surface layer away from the release paper to form a second coating, and performing a second drying process to obtain the top transparent electrode layer;

[0015] S3, coating the light-emitting layer slurry on the side of the top transparent electrode layer away from the polyurethane surface layer to form a third coating layer, and performing a third drying process to obtain a light-emitting layer;

[0016] S4, coating the dielectric layer slurry on the side of the light-emitting layer away from the top transparent electrode layer to form a fourth coating layer, and performing a fourth drying process to obtain a dielectric layer;

[0017] S5, coating the bottom electrode layer slurry on the side of the dielectric layer away from the light-emitting layer to form a fifth coating layer, and performing a fifth drying process to obtain a bottom electrode layer;

[0018] S6, coating an adhesive on a side of the bottom electrode layer away from the dielectric layer, and performing a hot pressing bonding process with the synthetic leather substrate to obtain the polyurethane synthetic leather;

[0019] Wherein, the luminous layer slurry, the dielectric layer slurry and the adhesive all contain the water-based polyurethane resin.

[0020] Furthermore, in S1, the thickness of the first coating layer is preferably 800-1200 μm.

[0021] Furthermore, in S1, the temperature of the first drying treatment is preferably 110-130°C, the oven length is 20-25m, and the vehicle speed is 10-12m / min.

[0022] Furthermore, in S2, the top transparent electrode layer slurry is preferably a polyaniline:polystyrene sulfonate solution with a solid content of 2-5wt%, a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate solution with a solid content of 2-5wt%, or a silver nanowire aqueous solution with a concentration of 5-10mg / mL.

[0023] Further, in S2, the thickness of the second coating layer is preferably 5-10 μm.

[0024] Furthermore, in S2, the temperature of the second drying treatment is preferably 130-140°C, the oven length is 40-60m, and the vehicle speed is 10-12m / min.

[0025] Further, in S3, the light-emitting layer slurry comprises the following components in parts by mass: 30-70 parts of electroluminescent powder, 30-70 parts of waterborne polyurethane resin, and 1-2 parts of aziridine crosslinking agent; preferably, the electroluminescent powder comprises at least one of ZnS:Cu, ZnS:Mn, and ZnS:Ag.

[0026] Furthermore, in S3, the thickness of the third coating is preferably 20-40 μm.

[0027] Furthermore, in S3, the temperature of the third drying treatment is preferably 130-140°C, the oven length is 40-60m, and the vehicle speed is 10-12m / min.

[0028] Further, in S4, the dielectric layer slurry comprises the following components in parts by mass: 30-50 parts of dielectric material, 50-70 parts of waterborne polyurethane resin, and 1-2 parts of aziridine crosslinking agent; preferably, the dielectric material comprises at least one of BaTiO3, TiO2, and SiO2.

[0029] Furthermore, in S4, the thickness of the fourth coating layer is preferably 10-20 μm.

[0030] Furthermore, in S4, the temperature of the fourth drying treatment is preferably 100-120° C., the time is preferably an oven length of 5-10 m, and the vehicle speed is 10-12 m / min.

[0031] Furthermore, in S5, the bottom electrode layer slurry is an aqueous dispersion containing single-walled carbon nanotubes and / or graphene, and the solid content of the aqueous dispersion is preferably 2-5 wt %.

[0032] Furthermore, in S5, the thickness of the fifth coating layer is preferably 5-10 μm.

[0033] Furthermore, in S5, the temperature of the fifth drying treatment is preferably 110-130°C, the oven length is 20-25m, and the vehicle speed is 10-12m / min.

[0034] Furthermore, in S6, the synthetic leather substrate is selected from one of woven fabric, non-woven fabric and microfiber fabric.

[0035] Furthermore, in S6, the temperature of the hot pressing bonding treatment is preferably 30-50°C, and the pressure is preferably 30-50Pa.

[0036] Furthermore, the waterborne polyurethane resin comprises the following components in parts by mass: 90-100 parts of waterborne polyurethane, 0.01-0.03 parts of polyether-modified siloxane wetting agent, 0.01-0.02 parts of silicone defoaming agent, and 3-5 parts of polyurethane associative thickener; more preferably, the waterborne polyurethane is an aliphatic polyester type and / or polyether type anionic waterborne polyurethane, and the light-emitting layer slurry and the dielectric layer slurry also contain an aziridine crosslinking agent.

[0037] Furthermore, the viscosity of the waterborne polyurethane resin is 2000-4000 mPa·s.

[0038] Furthermore, the preparation method further comprises the step of subjecting the polyurethane synthetic leather after the hot pressing bonding treatment to a aging treatment, wherein the aging treatment is preferably carried out at a temperature of 110-130° C. and for a time of 1-2 min.

[0039] In the method for preparing polyurethane synthetic leather capable of electroluminescent display provided by the present invention, the temperature and time of each drying treatment will affect the bonding strength between the layers of the final product.

[0040] The polyurethane synthetic leather capable of electroluminescent display provided by the present invention can be prepared by using a conventional water-based synthetic leather production line, as follows:

[0041] (1) Unwinding the release paper, evenly coating the surface of the release paper with waterborne polyurethane resin, controlling the thickness to be 800-1200 μm, and then drying in an oven with a length of 20-25 m, an oven temperature of 110-130° C., and a vehicle speed of 10-12 m / min;

[0042] (2) Then, a flexible top transparent electrode layer slurry is coated on the polyurethane coating, the coating thickness is controlled to be 5-10 μm, and the coating is placed in an oven for drying, the oven length is 40-60 m, the oven temperature is 130-140° C., and the vehicle speed is 10-12 m / min;

[0043] (3) Subsequently, the light-emitting layer slurry is coated on the surface of the top transparent electrode layer, the coating thickness is controlled to be 20-40 μm, and the coating is placed in an oven for drying, the oven length is 40-60 m, the oven temperature is 130-140° C., and the vehicle speed is 10-12 m / min;

[0044] (4) Then, the dielectric layer slurry is continuously coated on the surface of the light-emitting layer, the coating thickness is controlled to be 10-20 μm, and the coating is placed in an oven for drying, the oven length is 5-10 m, the oven temperature is 100-120° C., and the vehicle speed is 10-12 m / min;

[0045] (5) Then, a flexible bottom electrode layer slurry is coated on the surface of the dielectric layer, the coating thickness is controlled to be 5-10 μm, and the layer is placed in an oven for aging, the oven length is 20-25 m, the oven temperature is 110-130° C., and the vehicle speed is 10-12 m / min;

[0046] (6) Finally, a water-based polyurethane adhesive is coated on the surface of the bottom electrode layer, and the layer is hot-pressed and laminated to the synthetic leather substrate. The layer is then placed in an oven at 110-130°C for aging for 1-2 minutes. After cooling, separation of the paper and leather, and surface treatment, a polyurethane synthetic leather capable of electroluminescent display is obtained.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] 1. The present invention provides a polyurethane synthetic leather product with electroluminescent display, which gives the synthetic leather product a sense of technology and fashion, is of great significance for expanding its application field and enhancing its added value, and breaks through the dilemma of the single visual experience of the traditional synthetic leather surface.

[0049] 2. The functional layers of the electroluminescent display polyurethane synthetic leather of the present invention all adopt flexible organic coatings, and there is no need to integrate rigid LED elements for illumination, thereby effectively avoiding the foreign body sensation and other problems that may be caused by rigid components on the surface of leather products, and can effectively ensure the neatness, aesthetics and touch of the synthetic leather surface; at the same time, different from LED fixed-point illumination, the present invention can also achieve the leather surface luminescence effect of any customized pattern through the coating pattern design of each functional layer.

[0050] 3. The preparation method of the polyurethane synthetic leather product with electroluminescent display provided by the present invention is simple, does not need to change the traditional water-based synthetic leather production process, and is suitable for industrial production. In addition, the present invention optimizes the coating formula of each layer and controls the process parameters such as drying temperature and time, so that the prepared polyurethane synthetic leather is not only safe and environmentally friendly, but also has high interlayer bonding strength, good wear resistance and bending resistance, and can still maintain good luminescence performance after thousands of bends and tens of thousands of frictions, and has good application prospects in the field of electroluminescence. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 The polyurethane synthetic leather capable of electroluminescent display prepared by the present invention is in a state before being powered on;

[0052] Figure 2 The polyurethane synthetic leather capable of electroluminescent display prepared by the present invention has a luminescent display effect after the top electrode and the bottom electrode are electrified. DETAILED DESCRIPTION

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items. The term "includes" or "comprising" described in the present invention means that it may include or contain other components in addition to the components described. The term "includes" or "comprising" described in the present invention may also be replaced by the closed form "for" or "consisting of..."

[0054] The present invention is further described below in conjunction with specific embodiments and drawings so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0055] Example 1

[0056] This embodiment relates to the preparation of a polyurethane synthetic leather capable of electroluminescent display, which is specifically as follows:

[0057] (1) unwinding the release paper, and uniformly coating the surface of the release paper with a waterborne polyurethane resin having a viscosity of 2000 mPa·s obtained by mixing 90 parts of aliphatic polyester anionic waterborne polyurethane, 0.01 parts of polyether modified siloxane wetting agent, 0.01 parts of silicone defoaming agent and 3 parts of polyurethane associative thickener under high-speed stirring, and controlling the thickness to be 800 μm, and then putting the release paper into an oven for drying, with an oven length of 20 m, an oven temperature of 110° C., and a vehicle speed of 10 m / min;

[0058] (2) Then, a polyaniline: polystyrene sulfonate (PANI:PSS) flexible top transparent electrode layer slurry with a solid content of 2 wt% was coated on the polyurethane coating, the coating thickness was controlled to be 5 μm, and the coating was put into an oven for drying, the oven length was 40 m, the oven temperature was 130 °C, and the vehicle speed was 10 m / min;

[0059] (3) Subsequently, a luminescent layer slurry consisting of 30 parts of electroluminescent powder ZnS:Cu and 70 parts of an aqueous polyurethane resin with a viscosity of 2000 mPa·s obtained by mixing 90 parts of aliphatic polyester anionic waterborne polyurethane, 0.01 parts of polyether-modified siloxane wetting agent, 0.01 parts of silicone defoaming agent and 3 parts of polyurethane associative thickener under high-speed stirring and 1 part of aziridine crosslinking agent was applied, and the coating thickness was controlled at 20 μm. The coating was placed in an oven for drying, with an oven length of 40 m, an oven temperature of 130° C., and a vehicle speed of 10 m / min;

[0060] (4) coating the surface with a dielectric layer slurry consisting of 30 parts of BaTiO3 and 70 parts of 90 parts of aliphatic polyester anionic waterborne polyurethane, 0.01 parts of polyether modified siloxane wetting agent, 0.01 parts of silicone defoaming agent and 3 parts of polyurethane associative thickener with a viscosity of 2000 mPa·s and 1 part of aziridine crosslinking agent, controlling the coating thickness to 10 μm, and drying in an oven with an oven length of 5 m, an oven temperature of 120° C., and a vehicle speed of 10 m / min;

[0061] (5) coating a flexible bottom electrode layer slurry of a single-walled carbon nanotube aqueous dispersion with a solid content of 2 wt %, controlling the coating thickness to 5 μm, and placing the slurry in an oven for aging. The oven length is 20 m, the oven temperature is 130° C., and the vehicle speed is 10 m / min.

[0062] (6) Finally, a water-based polyurethane adhesive is coated on the leather, and the leather is hot-pressed and laminated with the woven fabric. The leather is then placed in an oven at 110° C. for aging for 2 min. After cooling, separation of the paper leather, and surface treatment, a polyurethane synthetic leather capable of electroluminescent display is obtained.

[0063] Compared with traditional polyurethane synthetic leather, the polyurethane synthetic leather prepared in this embodiment has an electroluminescent display function, and its luminescent performance can still be maintained after the synthetic leather is bent 1000 times (QB / T2714-2005) and rubbed 9600 times by the Martindale method (GB / T21196.1-2007).

[0064] Example 2

[0065] This embodiment relates to the preparation of a polyurethane synthetic leather capable of electroluminescent display, which is specifically as follows:

[0066] (1) unwinding the release paper, uniformly coating the surface of the release paper with a waterborne polyurethane resin having a viscosity of 3000 mPa·s obtained by mixing 95 parts of aliphatic polyether anionic waterborne polyurethane, 0.02 parts of polyether modified siloxane wetting agent, 0.01 parts of silicone defoaming agent and 4 parts of polyurethane associative thickener under high-speed stirring, and controlling the thickness to be 1000 μm, and then putting the release paper into an oven for drying, the oven length is 25 m, the oven temperature is 120° C., and the vehicle speed is 12 m / min;

[0067] (2) Then, a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate) (PEDOT:PSS) flexible top transparent electrode layer slurry with a solid content of 5 wt% was coated on the polyurethane coating, the coating thickness was controlled to be 8 μm, and the coating was placed in an oven for drying, the oven length was 50 m, the oven temperature was 140 °C, and the vehicle speed was 12 m / min;

[0068] (3) Subsequently, a luminescent layer slurry consisting of 50 parts of electroluminescent powder ZnS:Cu, 50 parts of aqueous polyurethane resin with a viscosity of 3000 mPa·s obtained by mixing 95 parts of aliphatic polyether anionic waterborne polyurethane, 0.02 parts of polyether modified siloxane wetting agent, 0.02 parts of silicone defoaming agent and 4 parts of polyurethane associative thickener under high-speed stirring, and 2 parts of aziridine crosslinking agent was applied, and the coating thickness was controlled at 30 μm. The coating was put into an oven for drying, with an oven length of 50 m, an oven temperature of 140°C, and a vehicle speed of 12 m / min;

[0069] (4) coating the surface with a dielectric layer slurry consisting of 50 parts of TiO2 and 50 parts of an aqueous polyurethane resin with a viscosity of 3000 mPa·s obtained by mixing 95 parts of aliphatic polyether anionic water-based polyurethane, 0.02 parts of polyether-modified siloxane wetting agent, 0.02 parts of silicone defoaming agent and 4 parts of polyurethane associative thickener under high-speed stirring, and 2 parts of aziridine crosslinking agent, controlling the coating thickness to 15 μm, and drying in an oven with an oven length of 10 m, an oven temperature of 100° C., and a vehicle speed of 12 m / min;

[0070] (5) coating a flexible bottom electrode layer slurry of a single-walled carbon nanotube aqueous dispersion with a solid content of 5 wt %, controlling the coating thickness to 8 μm, and entering an oven for aging, with an oven length of 25 m, an oven temperature of 120° C., and a vehicle speed of 12 m / min;

[0071] (6) Finally, a water-based polyurethane adhesive is coated on the surface, and the non-woven fabric is hot-pressed and laminated. The leather is placed in an oven at 130° C. for aging for 1 minute. After cooling, separation of paper and leather, and surface treatment, a polyurethane synthetic leather capable of electroluminescent display is obtained.

[0072] Compared with traditional polyurethane synthetic leather, the polyurethane synthetic leather prepared in this embodiment has an electroluminescent display function, and its luminescent performance can still be maintained after the synthetic leather is bent 1200 times (QB / T2714-2005) and rubbed 9800 times by the Martindale method (GB / T21196.1-2007).

[0073] Example 3

[0074] This embodiment relates to the preparation of a polyurethane synthetic leather capable of electroluminescent display, which is specifically as follows:

[0075] (1) unwinding the release paper, and uniformly coating the surface of the release paper with a waterborne polyurethane resin having a viscosity of 4000 mPa·s obtained by mixing 100 parts of aliphatic polyester anionic waterborne polyurethane, 0.03 parts of polyether modified siloxane wetting agent, 0.02 parts of silicone defoaming agent and 5 parts of polyurethane associative thickener under high-speed stirring, and controlling the thickness to be 1200 μm, and then putting the release paper into an oven for drying, with an oven length of 25 m, an oven temperature of 130° C., and a vehicle speed of 12 m / min;

[0076] (2) Then, a 10 mg / mL silver nanowire (AgNWs) aqueous solution flexible top transparent electrode layer slurry was coated on the polyurethane coating, the coating thickness was controlled to be 10 μm, and the coating was placed in an oven for drying, with an oven length of 60 m, an oven temperature of 130 °C, and a vehicle speed of 12 m / min;

[0077] (3) Subsequently, a luminescent layer slurry consisting of 70 parts of electroluminescent powder ZnS:Cu and 30 parts of an aqueous polyurethane resin with a viscosity of 4000 mPa·s obtained by mixing 100 parts of aliphatic polyester anionic waterborne polyurethane, 0.03 parts of polyether-modified siloxane wetting agent, 0.02 parts of silicone defoaming agent and 5 parts of polyurethane associative thickener under high-speed stirring and 2 parts of aziridine crosslinking agent was applied, and the coating thickness was controlled at 40 μm. The coating was then put into an oven for drying. The oven length was 60 m, the oven temperature was 140° C., and the vehicle speed was 12 m / min.

[0078] (4) coating the surface with a dielectric layer slurry consisting of 40 parts of SiO2 and 60 parts of an aqueous polyurethane resin with a viscosity of 4000 mPa·s obtained by mixing 100 parts of aliphatic polyester anionic water-based polyurethane, 0.03 parts of polyether-modified siloxane wetting agent, 0.02 parts of silicone defoaming agent and 5 parts of polyurethane associative thickener under high-speed stirring, and 2 parts of aziridine crosslinking agent, controlling the coating thickness to 20 μm, and drying in an oven with an oven length of 10 m, an oven temperature of 120° C., and a vehicle speed of 12 m / min;

[0079] (5) coating a flexible bottom electrode layer slurry of a graphene aqueous dispersion with a solid content of 5 wt %, controlling the coating thickness to 10 μm, and entering an oven for aging, with an oven length of 25 m, an oven temperature of 110° C., and a vehicle speed of 12 m / min;

[0080] (6) Finally, a water-based polyurethane adhesive is coated on the surface, and the surface is hot-pressed and laminated with the microfiber cloth. The surface is then placed in an oven at 130° C. for aging for 1 minute. After cooling, separation of the paper leather, and surface treatment, a polyurethane synthetic leather capable of electroluminescent display is obtained.

[0081] Compared with traditional polyurethane synthetic leather, the polyurethane synthetic leather prepared in this embodiment has an electroluminescent display function, and its luminescent performance can still be maintained after the synthetic leather is bent 1500 times (QB / T2714-2005) and rubbed 12000 times by the Martindale method (GB / T21196.1-2007).

[0082] Example 4

[0083] This embodiment relates to the preparation of a polyurethane synthetic leather capable of electroluminescent display, which is different from Embodiment 1 in that no aziridine crosslinking agent is added to the light-emitting layer slurry and the dielectric layer slurry, and the remaining operations are the same to prepare the corresponding polyurethane synthetic leather capable of electroluminescent display.

[0084] The polyurethane synthetic leather prepared in this embodiment has an electroluminescent display function. After the synthetic leather is bent 1000 times (QB / T2714-2005) and rubbed 4000 times by the Martindale method (GB / T21196.1-2007), the polyurethane synthetic leather loses its electroluminescent function.

[0085] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A polyurethane synthetic leather capable of electroluminescent display, characterized in that: The polyurethane synthetic leather comprises a polyurethane surface layer, a top transparent electrode layer, a light-emitting layer, a dielectric layer, a bottom electrode layer, an adhesive layer and a synthetic leather substrate layer which are stacked in sequence; The polyurethane surface layer, the light-emitting layer, the dielectric layer and the adhesive layer all contain water-based polyurethane resin.

2. The polyurethane synthetic leather according to claim 1, characterized in that: The waterborne polyurethane resin comprises the following components by mass: 90-100 parts of waterborne polyurethane, 0.01-0.03 parts of polyether-modified siloxane wetting agent, 0.01-0.02 parts of organosilicon defoaming agent, and 3-5 parts of polyurethane associative thickener; The waterborne polyurethane is an aliphatic polyester type and / or polyether type anionic waterborne polyurethane, and the slurry for forming the light-emitting layer and the slurry for forming the dielectric layer further contain an aziridine crosslinking agent.

3. A method for preparing polyurethane synthetic leather capable of electroluminescent display, characterized in that: The following steps are involved: S1, coating the surface of the release paper with a water-based polyurethane resin to form a first coating, and performing a first drying treatment to obtain a polyurethane surface layer; S2, coating the top transparent electrode layer slurry on the polyurethane surface layer to form a second coating layer, and performing a second drying process to obtain a top transparent electrode layer; S3, coating the light-emitting layer slurry on the top transparent electrode layer to form a third coating layer, and performing a third drying process to obtain a light-emitting layer; S4, coating the dielectric layer slurry on the light-emitting layer to form a fourth coating layer, and performing a fourth drying process to obtain a dielectric layer; S5, coating the bottom electrode layer slurry on the dielectric layer to form a fifth coating layer, and performing a fifth drying process to obtain a bottom electrode layer; S6, coating the adhesive on the bottom electrode layer, and performing a hot pressing bonding process with the synthetic leather substrate to obtain the polyurethane synthetic leather; Wherein, the luminous layer slurry, the dielectric layer slurry and the adhesive all contain the water-based polyurethane resin.

4. The preparation method according to claim 3, characterized in that: In S1: The thickness of the first coating is 800-1200 μm; The temperature of the first drying treatment is 110-130° C., the length of the oven is 20-25 m, and the vehicle speed is 10-12 m / min.

5. The preparation method according to claim 3, characterized in that: In S2: The top transparent electrode layer slurry is a polyaniline:polystyrene sulfonate solution with a solid content of 2-5wt%, a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate solution with a solid content of 2-5wt%, or a silver nanowire aqueous solution with a concentration of 5-10mg / mL; The thickness of the second coating is 5-10 μm; The temperature of the second drying treatment is 130-140° C., the length of the oven is 40-60 m, and the vehicle speed is 10-12 m / min.

6. The preparation method according to claim 3, characterized in that: In S3: The luminescent layer slurry comprises the following components by mass: 30-70 parts of electroluminescent powder, 30-70 parts of waterborne polyurethane resin, and 1-2 parts of aziridine crosslinking agent; the electroluminescent powder comprises at least one of ZnS:Cu, ZnS:Mn, and ZnS:Ag; The thickness of the third coating is 20-40 μm; The temperature of the third drying treatment is 130-140° C., the length of the oven is 40-60 m, and the vehicle speed is 10-12 m / min.

7. The preparation method according to claim 3, characterized in that: In S4: The dielectric layer slurry comprises the following components by mass: 30-50 parts of dielectric material, 50-70 parts of waterborne polyurethane resin, and 1-2 parts of aziridine crosslinking agent; the dielectric material comprises at least one of BaTiO3, TiO2, and SiO2; The thickness of the fourth coating is 10-20 μm; The temperature of the fourth drying treatment is 100-120° C., the length of the oven is 5-10 m, and the vehicle speed is 10-12 m / min.

8. The preparation method according to claim 3, characterized in that: In S5: The bottom electrode layer slurry is an aqueous dispersion containing single-walled carbon nanotubes and / or graphene, and the solid content of the aqueous dispersion is 2-5wt%; The thickness of the fifth coating is 5-10 μm; The temperature of the fifth drying treatment is 110-130° C., the length of the drying oven is 20-25 m, and the vehicle speed is 10-12 m / min.

9. The preparation method according to claim 3, characterized in that: In S6: The synthetic leather substrate is selected from one of woven fabric, non-woven fabric and microfiber fabric; The temperature of the hot pressing bonding process is 30-50°C and the pressure is 30-50Pa.

10. The preparation method according to claim 3, characterized in that: The waterborne polyurethane resin comprises the following components by mass: 90-100 parts of waterborne polyurethane, 0.01-0.03 parts of polyether-modified siloxane wetting agent, 0.01-0.02 parts of silicone defoaming agent, and 3-5 parts of polyurethane associative thickener; the waterborne polyurethane is aliphatic polyester type and / or polyether type anionic waterborne polyurethane, and the luminescent layer slurry and the dielectric layer slurry further comprise an aziridine crosslinking agent; The viscosity of the waterborne polyurethane resin is 2000-4000 mPa·s; The preparation method further comprises the step of subjecting the polyurethane synthetic leather after the heat-pressing bonding treatment to a aging treatment, wherein the aging treatment is carried out at a temperature of 110-130° C. and for a time of 1-2 minutes.

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