WO2022068271A1

WO2022068271A1 - Automobile sunscreen film and preparation method therefor

Info

Publication number: WO2022068271A1
Application number: PCT/CN2021/100960
Authority: WO
Inventors: 徐梦飞
Original assignee: 浙江远程车饰股份有限公司
Priority date: 2020-09-30
Filing date: 2021-06-18
Publication date: 2022-04-07
Also published as: CN112175537A; CN112175537B

Abstract

The present invention belongs to the technical field of functional films, and in particular relates to a sunscreen film for automobile window glass and a preparation method therefor. By coating glass nanospheres with aluminum and coating glass nanospheres with copper and silver, dispersing same in PET, and preparing a PET bidirectional stretching film, the glass nanospheres coated with different metals are respectively dispersed in the upper layer and the lower layer of the film. Aluminum is coated on the surface of the glass nanospheres, creating reflection and diffuse reflection, and the reflection of the aluminum metal layer will reflect back part of the infrared rays and ultraviolet rays of the light. The diffuse reflection enables the remaining infrared rays and ultraviolet rays to be absorbed by the ultraviolet absorber and the infrared absorber when diffused repeatedly, thereby effectively achieving the effect of thermal insulation. Copper and silver in the bottom layer are coated on the surface of the glass nanospheres, to reflect and diffuse the residual infrared rays and ultraviolet rays. Furthermore, by dispersing the metal-coated glass microspheres in PET, the problems that aluminum plating affects light transmission, the aluminum layer easily falls off, the metal coating strongly reflects light, etc. are overcome.

Description

A kind of automobile sunscreen sunshade film and preparation method thereof

technical field

The invention belongs to the technical field of functional films, and in particular relates to a sunscreen sunshade film for automobile window glass and a preparation method.

Background technique

Sunlight consists of ultraviolet (200nm～380nm), visible light (380nm～760nm) and infrared (760nm～2500nm). Ultraviolet light is an invisible light with a wavelength shorter than visible light, with a wavelength range of 280nm-400nm, and has significant chemical effects, such as commonly used for sterilization and disinfection. The sun rays contain more ultraviolet rays. If the ultraviolet rays are irradiated for a long time and excessively, it will cause burns to the human skin and eyes. Ultraviolet rays can damage human skin cells, causing wrinkles and pigmentation. Infrared is the fundamental source of heat generation in sunlight. In pursuit of transparency, automobiles use large areas of window glass, front windshield, sunroof glass, etc., resulting in a lot of direct sunlight inside the car. The strong ultraviolet rays and infrared rays in the sun make the people in the car easy to be burned, the temperature in the car increases, and the car decoration accelerates aging.

Car sunshade film is an effective way to solve the temperature rise and ultraviolet burn caused by direct sunlight in the car. At present, in order to protect the car, prevent ultraviolet rays from harming the human body, and prevent the interior of the car from heating up, most cars usually stick a sunshade film on the glass of the car. In addition, in addition to heat insulation and sun protection, the car sunshade film also has a certain explosion-proof function. For example, the film obtained from high-quality polyester materials has strong toughness. In the event of an accident, the glass is broken and the film is adhered firmly. without splashing and hurting people.

The development of automobile sunshade film has gone through four stages. The first stage is mainly to block the strong sunlight by coating brown color, which does not have the effect of heat insulation; the second stage mainly adopts the method of dyeing, and the added colorant can absorb the sun The infrared rays in the light achieve the effect of heat insulation, but the heat absorption is limited, and the use of more heat-absorbing materials affects the permeability of visible light; the third stage is the vacuum thermal evaporation film, which uses a vacuum thermal evaporation process to remove the aluminum layer. Evaporated on the substrate to achieve heat insulation effect, the film has good reflective effect and lasting heat insulation, but the visible light liquid is poor, resulting in low clarity and affecting the comfort of the field of vision; the fourth stage is metal magnetron sputtering It can evenly sputter various metals such as nickel, silver, titanium, and gold on the PET substrate. Relying on reflection, it can block the heat of infrared rays with high efficiency. However, due to the thick metal layer, it will affect the communication signal to a certain extent. , and the reflection is high, and the process is complicated, and the metal coating on the outer layer is easy to oxidize, fall off, and is not resistant to folding.

At present, most of the automotive films are made of aluminum, gold, copper, silver and other metals into multi-layered high-density high-insulation metal films by vacuum spraying or magnetron sputtering technology. When the metal material is irradiated by the light wave, the electric field of the light wave causes the free electrons to absorb the energy of the light, and generates an oscillation of the same frequency as the light, and this oscillation emits the light of the same frequency as the original light, so that the light is quickly reflected, so as to effectively To the role of sunscreen and sunshade. However, due to technical blockade, high-quality automobiles and sunshade films have poor technical stability, complex processes, high prices, high costs, and high requirements for production equipment. In addition, the existing metal coating has defects such as easy generation of wrinkles, uneven coating, and falling off of the aluminum layer.

Chinese Invention Patent Publication No. CN104130553A discloses an ultraviolet-proof solar film and a preparation method thereof, comprising 40-50 parts of PET polyester chips, 7-8 parts of inorganic ultraviolet absorber, 4-5 parts of anti-scratch agent, and anti-adhesion agent. 2 to 3 parts of the agent, 0.001 to 0.015 part of the β-1# decomposition and anti-reflection agent. A film with UV protection effect was prepared by melt extrusion and stretching. Although the invention cancels the complicated metal plating process, it has poor heat insulation, sun protection and sun shading effects.

SUMMARY OF THE INVENTION

At present, automobile sunshade film is prepared by magnetron sputtering process and multi-layer coating of functional coatings. Not only is the process complicated and the cost is high, but also aluminum plating affects light transmission, the aluminum layer is easy to fall off, and the metal layer is easy to cause problems such as strong reflection. To this end, the present invention proposes a sunscreen sunshade film for automobiles, and further specifically discloses a preparation method of the sunscreen sunshade film.

In order to achieve the above-mentioned technical effect, the present invention first provides a preparation method of a sunscreen sunshade film for automobiles, which is characterized in that the specific preparation method is as follows:

Step 1: heating aluminum to 700°C under vacuum conditions to completely melt to obtain aluminum paste; heating copper and silver in a mass ratio of 20-30:5-10 to 1100°C under vacuum conditions for complete melting to obtain composite copper-silver paste;

Step 2: Preheat the nano-glass microspheres to 500 °C, and use high-pressure argon to transport the nano-glass microspheres and aluminum paste to the upper part of the sedimentation chamber through two nozzles. After hitting and dispersing, the aluminum slurry coats the surface of the nano-glass microspheres, and gradually settles down to cool down, and collects the aluminum-coated nano-glass microspheres at the bottom of the sedimentation chamber;

Step 3: Preheat the nano-glass microspheres to 800°C, and use high-pressure argon to transport the nano-glass microspheres and composite copper-silver paste to the upper part of the sedimentation chamber through two nozzles under high pressure. In the upper part of the sedimentation chamber, the nano-glass microspheres and composite The copper-silver paste collides and disperses, and the composite copper-silver paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down, and collects the copper-silver-coated nano-glass microspheres at the bottom of the sedimentation chamber;

Step 4: Add PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer to a high-speed mixer to disperse evenly, and then transport to the co-rotating twin-screw The extruder melts, shears, disperses, extrudes and extrudes to obtain A material;

Step 5: Add PET homopolyester chips, copper-silver-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer into a high-speed mixer to disperse evenly, and transport to the same direction as The screw extruder melts, shears, disperses, extrudes and extrudes to obtain B material;

Step 6: Add material A and material B into the double-layer co-extrusion extruder, material A is the upper layer and material B is the lower layer, extruded and compounded into a cast sheet, cooled and shaped; then the cast sheet is preheated to 90-100 ℃, Stretch 3-5 times longitudinally, cool to 70°C; reheat to 105-110°C, stretch 3-4 times laterally, shape with a 60°C air-type hot roller, apply pressure-sensitive adhesive, paste release paper, and roll up , get a car sunscreen sunshade film.

Preferably, in step 2, the high-pressure argon gas adopts an air flow of 1-2 MPa, and the nano-glass microspheres and aluminum paste are transported by the high-pressure air flow, and are transported to the upper part of the sedimentation chamber through two opposite nozzles under high pressure, so that the nano-glass microspheres and the The aluminum paste is collided and dispersed, so that the aluminum paste is evenly coated on the surface of the nano-glass microspheres; further preferably, the mass ratio of the nano-glass microspheres and the aluminum paste is 100:15-20. Aluminum-coated nano-glass microspheres are easy to disperse in PET. At the same time, aluminum is coated on the surface of nano-glass microspheres, and there is reflection and diffuse reflection. The reflection of the aluminum metal layer will reflect part of the infrared rays and ultraviolet rays in the light; diffuse The reflection causes the remaining infrared rays and ultraviolet rays to be repeatedly absorbed by the ultraviolet absorber and the infrared absorber, thereby effectively playing the role of heat insulation.

Further preferably, the particle size of the nano-glass microspheres in steps 2 and 3 is 20-50 nm.

Preferably, the high-pressure argon gas in step 3 adopts an air flow of 1-2 MPa, and the nano-glass microspheres and composite copper-silver paste are transported to the upper part of the sedimentation chamber through two nozzles under high pressure by high-pressure airflow transportation. The microspheres and the composite copper-silver paste collide and disperse, and the composite copper-silver paste coats the surface of the nano-glass microspheres; further preferably, the mass ratio of the nano-glass microspheres and the composite copper-silver paste is 100:5-10.

Preferably, in step 4, the mass ratio of PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:10-15: 1-2: 0.1-0.3: 0.1-0.3: 0.5-1: 0.2-0.5.

Preferably, in step 5, the mass ratio of PET homopolyester chips, copper-silver-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:3- 8:1-2:0.1-0.3:0.1-0.3:0.5-1:0.2-0.5.

Further preferably, in step 4 and step 5, the ultraviolet absorber is composed of 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; the infrared absorption The agent is selected from at least one of nanometer indium tin oxide, nanometer tin antimony and nanometer tungsten cesium tungsten oxide; the stabilizer is barium zinc stabilizer.

Further preferably, in step 4 and step 5, the screw length-diameter ratio of the co-rotating twin-screw extruder is 40-44, and the longer length-diameter ratio is conducive to the shearing and uniform dispersion of the material; the screw temperature is controlled at 200. -220℃; screw speed is 120-180r/min.

Preferably, in step 6, the mass ratio of material A and material B is 2:1; the pressure-sensitive adhesive is a water-based polyacrylate pressure-sensitive adhesive.

Preferably, in step 6, the temperature of the double-layer co-extrusion extruder is controlled at 220-230° C., and the temperature of the die mouth is controlled at 190-200° C., so that the upper and lower layers are compounded into cast sheets through the die mouth.

Furthermore, the present invention proposes a sunscreen sunshade film for automobiles prepared by the above method. As a result, the current automobile sunshade film adopts magnetron sputtering process and multi-layer functional coating method to prepare complex process, aluminum plating affects light transmission, aluminum layer is easy to fall off, and metal layer is easy to cause strong reflection and other problems. To this end, the present invention coats nano-glass microspheres with aluminum and copper and silver on nano-glass microspheres and disperses them in PET, and prepares a PET biaxially oriented film, so that different metals are coated on nano-glass microspheres and dispersed respectively. On the upper and lower layers of the film, the method greatly simplifies the preparation process of the sunscreen and sunscreen film and improves the preparation ability; moreover, the aluminum is coated on the surface of the nano-glass microspheres, and there is reflection and diffuse reflection. The reflection of the aluminum metal layer will cause the light Some of the infrared rays and ultraviolet rays are reflected back; the diffuse reflection makes the remaining infrared rays and ultraviolet rays absorb when the ultraviolet absorbers and infrared absorbers repeatedly diffuse, so as to effectively play the role of heat insulation; the copper silver on the bottom layer is coated on the nano glass microspheres The surface reflects and diffuses the missing infrared rays and ultraviolet rays, so as to achieve the purpose of sufficient sun protection and heat insulation. Further, the metal-coated glass microspheres are dispersed in PET, which overcomes the problems of aluminum plating affecting light transmission, easy falling off of aluminum layer, and strong reflection of metal coating.

Compared with the existing automobile sunshade film, the present invention has the outstanding features and remarkable progress as follows:

(1) The present invention utilizes metal-coated nano-glass microspheres, which are dispersed in a PET film for reflection and diffuse reflection so as to consume infrared rays and ultraviolet rays, and achieve the purpose of sun protection and sunshade.

(2) In the present invention, by double-layer co-extrusion, microspheres with different reflection effects are distributed on the upper and lower layers, supplementary reflection and diffuse absorption of infrared rays and ultraviolet rays missed by the upper layer, and improve the effect of sun protection and sunshade.

(3) The present invention increases the sunscreen effect by cooperating with suitable ultraviolet absorbers and infrared absorbers, so that the diffusely reflected infrared rays and ultraviolet rays are gradually consumed.

(4) Compared with methods such as magnetron sputtering process, multi-layer coating functional coating, etc., the present invention is simple in process, low in equipment requirements, and the obtained film does not have an aluminized layer, with good light transmission and no strong reflection. , suitable for large-scale production of biaxially oriented film enterprises.

Description of drawings

The technical scheme of the present invention is further described below in conjunction with the accompanying drawings:

Figure 1 is a schematic structural diagram of the sunscreen sunshade film for automobiles of the present invention; wherein: 1-upper layer PET; 2-lower layer PET; 3-aluminum-coated nano-glass microspheres; 4-copper-silver-coated nano-glass microspheres.

Detailed ways

In order to make those skilled in the art better understand the solution of the present invention, the technical solution of the present invention will be described clearly and completely below with reference to the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and Not all examples. Based on the technical idea of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

Example 1

Step 1: heating aluminum to 700°C in a vacuum condition to completely melt to obtain an aluminum paste; heating copper and silver to 1100°C in a mass ratio of 20:5 in a vacuum condition to completely melt to obtain a composite copper-silver paste;

Step 2: Preheat the nano-glass microspheres with a particle size of 20-50 nm to 500°C, and use high-pressure argon gas to transport the nano-glass microspheres and aluminum paste to the upper part of the sedimentation chamber through two counter-jet nozzles at a high pressure with an airflow of 2 MPa. In the upper part of the chamber, the nano-glass microspheres and the aluminum paste collide and disperse. The aluminum paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down. The aluminum-coated nano-glass microspheres are collected at the bottom of the sedimentation chamber; , The mass ratio of aluminum paste is 100:15;

Step 3: Preheat the nano-glass microspheres with a particle size of 20-50nm to 800°C, and use high-pressure argon gas with an airflow of 1 MPa to transport the nano-glass microspheres and composite copper-silver paste to a high pressure through two opposite spray nozzles. In the upper part of the sedimentation chamber, the nano-glass microspheres and the composite copper-silver paste collide and disperse, and the composite copper-silver paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down, and the copper-silver is collected at the bottom of the sedimentation chamber. Coating nano-glass microspheres; the mass ratio of the nano-glass microspheres and the composite copper-silver paste is 100:5;

Step 4: The mass ratio of PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:15:1:0.3: 0.3:0.5:0.5 is added to a high-speed mixer to disperse evenly, and then conveyed to a co-rotating twin-screw extruder with an aspect ratio of 40. The temperature of the screw is controlled at 220°C, and the screw speed is 150r/min. , to obtain A material; ultraviolet absorber selects 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide to be compounded with mass ratio of 1:1; infrared absorber selects nano-indium tin oxide; stabilizer is barium Zinc stabilizer;

Step 5: The mass ratio of PET homopolyester chips, copper-silver-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:5:1:0.1 : 0.2: 0.5: 0.5 is added to the high-speed mixer to disperse evenly, and then sent to the co-rotating twin-screw extruder. The screw length-diameter ratio of the co-rotating twin-screw extruder is 40, and the screw temperature is controlled at 210 °C; the screw speed is 120r/min , melt shear dispersion extrusion granulation, obtain B material; ultraviolet absorber is selected from 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; the infrared absorber is selected Nano tungsten cesium tungsten oxide; stabilizer is barium zinc stabilizer;

Step 6: Add material A and material B into the double-layer co-extrusion extruder, material A is the upper layer, material B is the lower layer, and the mass ratio of material A and material B is 2:1; the temperature of the double-layer co-extrusion extruder is Controlled at 220°C, the die temperature was controlled at 200°C, the upper and lower layers were compounded into cast pieces through the die mouth, and cooled and shaped; then the cast sheets were preheated to 100°C, longitudinally stretched 3 times, and cooled to 70°C; reheated to 110° C., transversely stretched by 4 times, shaped with a 60° C. air-type hot roller, coated with water-based polyacrylate pressure-sensitive adhesive, pasted with release paper, and rolled to obtain a car sunscreen sunshade film.

The schematic diagram of the structure of the sunscreen and sunshade film is shown in Figure 1, wherein: 1-upper layer PET; 2-lower layer PET; 3-aluminum-coated nano-glass microspheres; 4-copper-silver-coated nano-glass microspheres.

Example 2

Step 1: heating aluminum to 700°C under vacuum conditions to completely melt to obtain aluminum paste; heating copper and silver to 1100°C in a mass ratio of 30:10 under vacuum conditions to completely melt to obtain composite copper-silver paste;

Step 2: Preheat the nano-glass microspheres with a particle size of 20-50 nm to 500 °C, and use high-pressure argon gas to transport the nano-glass microspheres and aluminum paste to the upper part of the sedimentation chamber through two counter-jet nozzles at a high pressure with an airflow of 1 MPa. In the upper part of the chamber, the nano-glass microspheres and the aluminum paste collide and disperse. The aluminum paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down. The aluminum-coated nano-glass microspheres are collected at the bottom of the sedimentation chamber; , the mass ratio of aluminum paste is 100:20;

Step 3: Preheat the nano-glass microspheres with a particle size of 20-50nm to 800°C, and use high-pressure argon gas to transport the nano-glass microspheres and composite copper-silver paste through two counter-jet nozzles to a high-pressure gas stream of 2 MPa. In the upper part of the sedimentation chamber, the nano-glass microspheres and the composite copper-silver paste collide and disperse, and the composite copper-silver paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down, and the copper-silver is collected at the bottom of the sedimentation chamber. Coating nano-glass microspheres; the mass ratio of the nano-glass microspheres and the composite copper-silver paste is 100:10;

Step 4: The mass ratio of PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:15:2:0.3: 0.3:1:0.2 was added to a high-speed mixer for uniform dispersion, and then sent to a co-rotating twin-screw extruder. The screw length-diameter ratio of the co-rotating twin-screw extruder was 40, and the screw temperature was controlled at 220°C; the screw speed was 120r/min , melt shear dispersion extrusion granulation to obtain A material; ultraviolet absorber is selected from 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; the infrared absorber is selected from Nano tin antimony oxide; stabilizer is barium zinc stabilizer;

Step 5: The mass ratio of PET homopolyester chips, copper-silver-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:8:1:0.3 : 0.3: 0.5: 0.2 is added to a high-speed mixer to disperse evenly, and then sent to a co-rotating twin-screw extruder. The screw length-diameter ratio of the co-rotating twin-screw extruder is 40, and the screw temperature is controlled at 220 °C; the screw speed is 180r/ min, melt, shear, disperse, extrude and granulate to obtain material B; the ultraviolet absorber is composed of 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; infrared absorber Select nano-tungsten cesium tungsten oxide; stabilizer is barium zinc stabilizer;

Step 6: Add material A and material B into the double-layer co-extrusion extruder, material A is the upper layer, material B is the lower layer, and the mass ratio of material A and material B is 2:1; the temperature of the double-layer co-extrusion extruder is Controlled at 230°C, the die temperature was controlled at 200°C, the upper and lower layers were compounded into cast pieces through the die mouth, cooled and shaped; then the cast sheets were preheated to 100°C, stretched 5 times longitudinally, and cooled to 70°C; reheated to 110° C., transversely stretched by 4 times, shaped with a 60° C. air-type hot roller, coated with water-based polyacrylate pressure-sensitive adhesive, pasted with release paper, and rolled to obtain a car sunscreen sunshade film.

Example 3

Step 1: heating aluminum to 700°C under vacuum conditions to completely melt to obtain aluminum paste; heating copper and silver in a mass ratio of 30:8 to 1100°C under vacuum conditions to completely melt to obtain composite copper-silver paste;

Step 2: Preheat the nano-glass microspheres with a particle size of 20-50 nm to 500°C, and use high-pressure argon gas to transport the nano-glass microspheres and aluminum paste to the upper part of the sedimentation chamber through two counter-jet nozzles at a high pressure with an airflow of 2 MPa. In the upper part of the chamber, the nano-glass microspheres and the aluminum paste collide and disperse. The aluminum paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down. The aluminum-coated nano-glass microspheres are collected at the bottom of the sedimentation chamber; , the mass ratio of aluminum paste is 100:20;

Step 4: The mass ratio of PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:15:1:0.3: 0.3:0.5:0.2 is added to the high-speed mixer to disperse evenly, and then sent to the co-rotating twin-screw extruder. The screw length-diameter ratio of the co-rotating twin-screw extruder is 40, and the screw temperature is controlled at 220 °C; the screw speed is 150r/min , melt shear dispersion extrusion granulation to obtain A material; ultraviolet absorber is selected from 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; the infrared absorber is selected from Nano indium tin oxide; stabilizer is barium zinc stabilizer;

Step 5: The mass ratio of PET homopolyester chips, copper-silver-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:5:1:0.3 : 0.3: 1: 0.2 is added to the high-speed mixer to disperse evenly, and then sent to the co-rotating twin-screw extruder. The screw length-diameter ratio of the co-rotating twin-screw extruder is 40, and the screw temperature is controlled at 2100 ° C; the screw speed is 120r/ min, melt, shear, disperse, extrude and granulate to obtain material B; the ultraviolet absorber is composed of 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; infrared absorber Nano-indium tin oxide is selected; the stabilizer is barium-zinc stabilizer;

Step 6: Add material A and material B into the double-layer co-extrusion extruder, material A is the upper layer, material B is the lower layer, and the mass ratio of material A and material B is 2:1; the temperature of the double-layer co-extrusion extruder is Controlled at 230°C, the die temperature was controlled at 200°C, the upper and lower layers were compounded into cast pieces through the die mouth, cooled and shaped; then the cast sheets were preheated to 100°C, stretched 5 times longitudinally, and cooled to 70°C; reheated to 105° C., transversely stretched by 3 times, shaped with a 60° C. air-type hot roller, coated with water-based polyacrylate pressure-sensitive adhesive, pasted with release paper, and rolled to obtain a car sunscreen sunshade film.

Comparative Example 1

Material A and material B obtained in Example 1 were mixed at a mass ratio of 2:1, added to a single-layer extruder, the temperature of the extruder was controlled at 220°C, and the die temperature was controlled at 200°C to obtain cast pieces, which were cooled and shaped. ; Then preheat the cast sheet to 100°C, stretch 3 times longitudinally, cool to 70°C; reheat to 110°C, stretch 4 times laterally, shape with a 60°C air-type hot roller, coat with water-based polyacrylate press Sensitive glue, sticking release paper, and rolling to obtain a sunscreen sunshade film for automobiles.

In Comparative Example 1, the aluminum-coated nano-glass microspheres and the copper-silver-coated nano-glass microspheres were not compounded in two layers of PET, but directly mixed to form. Due to the lack of remedial reflection and absorption of missing ultraviolet and infrared light, So that the shading and sun protection effects are affected to a certain extent.

Comparative Example 2

Step 1: grinding aluminum into nano powder; grinding copper and silver into nano powder with a mass ratio of 20:5;

Step 2: The mass ratio of PET homopolyester chips, nano aluminum powder, nano titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer is: 100:15:1:0.3:0.3:0.5: 0.5 is added to a high-speed mixer to disperse evenly, and then conveyed to a co-rotating twin-screw extruder with an aspect ratio of 40. The temperature of the screw is controlled at 220 °C, and the screw speed is 150 r/min. 2-hydroxy-4-n-octyloxy benzophenone and nano-cerium oxide are used as the ultraviolet absorber to be compounded in a mass ratio of 1:1; the infrared absorber is selected from nano-indium tin oxide; the stabilizer is barium-zinc stabilizer;

Step 3: The mass ratio of PET homopolyester chips, nano copper silver powder, nano titanium powder, ultraviolet absorber, infrared absorber, calcium stearate and stabilizer is: 100:5:1:0.1:0.2:0.5: 0.5 is added to a high-speed mixer to disperse evenly, and then sent to a co-rotating twin-screw extruder. The screw length-diameter ratio of the co-rotating twin-screw extruder is 40, and the screw temperature is controlled at 210 °C; the screw speed is 120 r/min, melt shear dispersion Extrusion and granulation to obtain material B; the ultraviolet absorber is selected from 2-hydroxy-4-n-octyloxybenzophenone and nano-cerium oxide in a mass ratio of 1:1; the infrared absorber is selected from nano-tungsten cesium tungsten oxide ; Stabilizer is barium zinc stabilizer;

Step 4: Add material A and material B into the double-layer co-extrusion extruder, material A is the upper layer, material B is the lower layer, and the mass ratio of material A and material B is 2:1; the temperature of the double-layer co-extrusion extruder is Controlled at 220°C, the die temperature was controlled at 200°C, the upper and lower layers were compounded into cast pieces through the die mouth, and cooled and shaped; then the cast sheets were preheated to 100°C, longitudinally stretched 3 times, and cooled to 70°C; reheated to 110° C., transversely stretched by 4 times, shaped with a 60° C. air-type hot roller, coated with water-based polyacrylate pressure-sensitive adhesive, pasted with release paper, and rolled to obtain a car sunscreen sunshade film.

Comparative Example 2 did not form metal-coated glass microspheres for reuse, but directly used metal nano-powders. On the one hand, the cost was higher and more metal was used. The radiation surface lacks repeated reflection and absorption of ultraviolet and infrared rays, and the blocking properties of ultraviolet and infrared rays in sunlight are reduced. Moreover, since more metal is used, glass microspheres are not used, which reduces the visible light transmittance of the obtained film.

The optical transmittance measuring instrument is used to directly obtain the transmittance of the sunshade film to the visible light, ultraviolet light, and infrared light; . As shown in Table 1.

Table 1:

Through testing, the sunscreen sunshade film prepared by the technology of the present invention has a good blocking effect on ultraviolet rays and infrared rays while ensuring good light transmittance, and can effectively achieve the purpose of sunscreen and sunshade and prevent the temperature inside the car from rising. It is greatly simplified in magnetron sputtering, multi-layer coating, etc. In Comparative Example 1, the aluminum-coated nano-glass microspheres and the copper-silver-coated nano-glass microspheres were not compounded in two layers of PET, but directly mixed to form. Due to the lack of remedial reflection and absorption of missing ultraviolet and infrared light, Although the light transmittance is good, the shading and sun protection effects are affected to a certain extent. Comparative Example 2 did not form metal-coated glass microspheres for reuse, but directly used metal nano-powders. The spherical surface of the glass microspheres was not used to form a reflective and diffusing surface, and it lacked repeated reflection and absorption of ultraviolet and infrared rays. Reduced UV and IR blocking. Moreover, since more metal is used, glass microspheres are not used, which reduces the visible light transmittance of the obtained film.

Claims

A preparation method of automobile sunscreen sunshade film, characterized in that the specific preparation method is as follows:

Step 1: heating aluminum to 700°C under vacuum conditions to completely melt to obtain aluminum paste; heating copper and silver in a mass ratio of 20-30:5-10 to 1100°C under vacuum conditions for complete melting to obtain composite copper-silver paste;

Step 2: Preheat the nano-glass microspheres to 500 °C, and use high-pressure argon to transport the nano-glass microspheres and aluminum paste to the upper part of the sedimentation chamber through two nozzles. After hitting and dispersing, the aluminum slurry coats the surface of the nano-glass microspheres, and gradually settles down to cool down, and collects the aluminum-coated nano-glass microspheres at the bottom of the sedimentation chamber;

Step 3: Preheat the nano-glass microspheres to 800°C, and use high-pressure argon to transport the nano-glass microspheres and composite copper-silver paste to the upper part of the sedimentation chamber through two nozzles under high pressure. In the upper part of the sedimentation chamber, the nano-glass microspheres and composite The copper-silver paste collides and disperses, and the composite copper-silver paste coats the surface of the nano-glass microspheres, and gradually settles down to cool down, and collects the copper-silver-coated nano-glass microspheres at the bottom of the sedimentation chamber;

Step 4: Add PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer to a high-speed mixer to disperse evenly, and then transport to the co-rotating twin-screw The extruder melts, shears, disperses, extrudes and extrudes to obtain A material;

Step 5: Add PET homopolyester chips, copper-silver-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber, calcium stearate, and stabilizer into a high-speed mixer to disperse evenly, and transport to the same direction as The screw extruder melts, shears, disperses, extrudes and extrudes to obtain B material;

Step 6: Add material A and material B into the double-layer co-extrusion extruder, material A is the upper layer and material B is the lower layer, extruded and compounded into a cast sheet, cooled and shaped; then the cast sheet is preheated to 90-100 ℃, Stretch 3-5 times longitudinally, cool to 70°C; reheat to 105-110°C, stretch 3-4 times laterally, shape with a 60°C air-type hot roller, apply pressure-sensitive adhesive, paste release paper, and roll up , get a car sunscreen sunshade film.
The method for preparing a sunscreen sunshade film for automobiles according to claim 1, characterized in that: in step 2, the high-pressure argon gas adopts an airflow of 1-2MPa; the mass ratio of the nano-glass microspheres to the aluminum paste is 100 : 15-20.
The method for preparing an automobile sunscreen sunshade film according to claim 1, wherein the particle size of the nano-glass microspheres in steps 2 and 3 is 20-50 nm.
The method for preparing an automobile sunscreen sunshade film according to claim 1, wherein the high-pressure argon gas in step 3 adopts an airflow of 1-2 MPa; the mass ratio of the nano-glass microspheres to the composite copper-silver paste is 100:5-10.
The preparation method of a sunscreen sunshade film for automobiles according to claim 1, characterized in that: in step 4, PET homopolyester chips, aluminum-coated nano-glass microspheres, nano-titanium powder, ultraviolet absorbers, infrared absorbers, hard The mass ratio of calcium fatty acid to stabilizer is: 100:10-15:1-2:0.1-0.3:0.1-0.3:0.5-1:0.2-0.5.
The method for preparing a sunscreen sunshade film for automobiles according to claim 1, characterized in that: in step 5, PET homopolyester chips, copper-silver coated nano-glass microspheres, nano-titanium powder, ultraviolet absorber, infrared absorber The mass ratio of calcium stearate and stabilizer is: 100:3-8:1-2:0.1-0.3:0.1-0.3:0.5-1:0.2-0.5.
A kind of preparation method of automobile sunscreen sunshade film according to claim 1, is characterized in that: in step 4, step 5, described ultraviolet absorber selects 2-hydroxy-4-n-octyloxybenzophenone and nanometer The cerium oxide is compounded at a mass ratio of 1:1; the infrared absorber is selected from at least one of nanometer indium tin oxide, nanometer tin antimony oxide, and nanometer tungsten cesium tungsten oxide; the stabilizer is barium zinc stabilizer; The screw length-diameter ratio of the co-rotating twin-screw extruder is 40-44; the screw temperature is controlled at 200-220° C.; the screw speed is 120-180 r/min.
A kind of preparation method of automobile sunscreen sunshade film according to claim 1, is characterized in that: in step 6, the mass ratio of A material and B material is 2: 1; Described pressure-sensitive adhesive adopts water-based polyacrylate pressure-sensitive adhesive .
The method for preparing an automobile sunscreen sunshade film according to claim 1, wherein in step 6, the temperature of the double-layer co-extrusion extruder is controlled at 220-230°C, and the die temperature is controlled at 190-200°C, The upper and lower layers are compounded into cast pieces through the die.
A car sunscreen sunshade film prepared by the method of any one of claims 1-9.