CN114044933B

CN114044933B - Sandwich-structure aluminum-plated film and preparation method thereof

Info

Publication number: CN114044933B
Application number: CN202111418339.XA
Authority: CN
Inventors: 林善华; 陈永群; 魏国华; 欧流志
Original assignee: Foshan Cailong Coating Packaging Materials Co ltd
Current assignee: Foshan Cailong Coating Packaging Materials Co ltd
Priority date: 2021-11-25
Filing date: 2021-11-25
Publication date: 2022-06-10
Anticipated expiration: 2041-11-25
Also published as: CN114044933A

Abstract

The application relates to the technical field of aluminizers, and particularly discloses a novel sandwich-structure aluminizer and a preparation method thereof. A novel sandwich structure aluminizer is of a four-layer sandwich structure of a basal layer/an aluminum layer-an aluminum oxide layer-an aluminum layer and comprises the basal layer, a first aluminizer layer plated on the basal layer, an aluminum oxide layer plated on the first aluminizer layer and a second aluminizer layer plated on the aluminum oxide layer; the first aluminum layer has a thickness of 200-500 angstroms, the aluminum oxide layer has a thickness of 1000-2000 angstroms, and the second aluminum layer has a thickness of 200-500 angstroms. The aluminium oxide layer reduces the second aluminized layer and takes place by the phenomenon of corroding, and first aluminized layer has further kept off vapor and alkaline cement mortar and has taken place the reaction with the second aluminized layer, and the heat reflection effect of this application stratum basale/first aluminized layer-aluminium oxide layer-four layers sandwich structure aluminizer of second aluminized layer is good, and corrosion resistance is strong, and the reliability is high.

Description

Sandwich-structure aluminum-plated film and preparation method thereof

Technical Field

The application relates to the technical field of vacuum aluminizer, in particular to an aluminizer with a sandwich structure and a preparation method thereof.

Background

The reflective film is one of floor heating paving materials, and has the main function of preventing heat from dissipating from the ground in floor heating, so that the heat reflection and radiation capability are effectively improved, and the constancy of indoor temperature is ensured.

The floor heating reflecting film is formed by compounding a base material and a surface film, the base material can be divided into three types, namely a paper base film, a cloth base film and a heat insulation material composite film, and the surface film generally adopts an aluminized film or an aluminum foil film. Wherein, the surface of the paper-based film is smooth and has higher brightness, but the paper-based film has poor tensile strength, is generally an acidic compound, and the surface of the paper-based film is covered on alkaline cement mortar; in addition, cement mortar is easy to separate and a paper-based reflective film in hand washing is easy to separate, so that the cement mortar fails to lose the heat reflection function

The paper-based reflecting film is easily separated and absorbed by cement mortar, so that the paper-based reflecting film is easy to lose effectiveness and lose a heat reflecting function, and a large amount of transfer loss of floor heating heat is caused;

the cloth-based reflecting film has good tensile strength, but the thin aluminum film on the surface layer of the cloth-based reflecting film is also separated and absorbed by alkaline cement mortar quickly, so that the reliability of the heat reflecting function of the cloth-based reflecting film is also low.

The heat-insulating material composite membrane is formed by compounding a thin-layer heat-insulating material and an aluminized film, comprises an EPE composite membrane, an EVA composite membrane, a cushion composite membrane and the like, but has the problems of generally poor overall heat-insulating effect and low heat reflectivity after oxidation of the aluminized film layer due to the thin heat-insulating layer.

Because the substrate and the surface are plated with the aluminum film layers, the problem of low heat reflectivity exists, and the heat reflection effect of the floor heating reflection film is poor.

Disclosure of Invention

In order to improve the heat reflection effect of the floor heating reflection film, the application provides an aluminum plating film with a sandwich structure and a preparation method thereof.

In a first aspect, the present application provides a sandwich structure aluminum plating film, which adopts the following technical scheme:

an aluminum-plated film with a sandwich structure is of a four-layer sandwich structure of a substrate layer/an aluminum layer-an aluminum oxide layer-an aluminum layer and comprises the substrate layer, a first aluminum-plated layer plated on the substrate layer, the aluminum oxide layer plated on the first aluminum-plated layer and a second aluminum-plated layer plated on the aluminum oxide layer;

the first aluminum layer has a thickness of 200-500 angstroms, the aluminum oxide layer has a thickness of 1000-2000 angstroms, and the second aluminum layer has a thickness of 200-500 angstroms.

Due to the fact that the corrosion resistance and the adhesive force of the aluminum coating of the floor heating reflection film in the related technology are poor, the heat reflection effect of the floor heating reflection film is poor.

The aluminum oxide layer can block alkaline cement mortar, so that the phenomenon that the second aluminum plating layer is corroded is reduced; in addition, the first aluminum coating can react with the alkaline cement mortar to generate metaaluminate to be attached to the surface of the aluminum oxide coating, and further prevents the water vapor and the alkaline cement mortar from reacting with the second aluminum coating. Because the second aluminized layer is located the most surface of aluminizer, mainly plays the effect of reflecting the heat of ground heating, consequently this application can prevent through the cooperation of aluminium oxide layer and first aluminized layer that the second aluminized layer from receiving the corruption of alkaline cement mortar to guarantee sandwich structure aluminizer's heat reflection effect, improve sandwich structure aluminizer's heat reflectivity, the corrosion resistance of aluminium oxide layer is strong, and then improves this sandwich structure aluminizer's reliability.

In addition, the second aluminum plating layer is easy to corrode due to the fact that the aluminum oxide layer is too thin, and pores of the aluminum oxide layer are increased due to the fact that the aluminum oxide layer is too thick, and the barrier property of the aluminum oxide layer is reduced; the corrosion resistance and the heat reflectivity of the sandwich-structure aluminum plating film are easily reduced due to the fact that the first aluminum plating layer and the second aluminum plating layer are too thin, the toughness of the first aluminum plating layer and the second aluminum plating layer is reduced due to the fact that the first aluminum plating layer and the second aluminum plating layer are too thick, stress concentration and cracks are easily generated in practical application of the first aluminum plating layer and the second aluminum plating layer, the tensile strength of the sandwich-structure aluminum plating film is reduced, and the heat reflectivity of the sandwich-structure aluminum plating film is influenced.

Preferably, the substrate layer comprises a BOPET film and a first coating layer coated on the BOPET film, and the first coating layer is made of raw materials including the following parts by weight:

50-250 parts of waterborne polyurethane;

10-15 parts of nano silicon dioxide;

0.5-3 parts of hydrolysis resistant agent;

0.1-1.5 parts of antioxidant.

Due to the fact that the tensile strength of a common base material is poor, the BOPET film is good in mechanical performance, high-temperature resistant and strong in chemical corrosion resistance by the aid of the technical scheme, and the BOPET film is used as the base material of the floor heating reflecting film, so that the tensile strength of the aluminum-plated film with the sandwich structure is increased, and the side heat reflecting effect of the aluminum-plated film with the sandwich structure is further improved.

The waterborne polyurethane has good adhesive force on the BOPET film and can block water vapor, and the nano silicon dioxide can increase the surface roughness of the first coating layer and improve the adhesive firmness of the subsequent coating layer; because the floor heating reflecting film is in an underground high-temperature environment for a long time, the antioxidant and the anti-hydrolysis agent in the first coating layer can improve the stability of the base layer, and the durability of the sandwich structure aluminum plating film is further improved.

Preferably, a second coating layer is coated on the surface of the second aluminum-plated layer, and the second coating layer is prepared from the following raw materials in parts by weight:

8-10 parts of epoxy resin;

1-4 parts of potassium silicate.

By adopting the technical scheme, the epoxy resin has better chemical corrosion resistance and heat resistance and high adhesive force on metal, and the potassium silicate added into the epoxy resin can improve the high-temperature resistance and corrosion resistance effects of the second coating layer, reduce the corrosion phenomenon of the second aluminum plating layer and further improve the corrosion resistance of the sandwich-structure aluminum plating film.

Preferably, the mass ratio of the hydrolysis resistant agent to the waterborne polyurethane is (0.5-2%): 1.

By adopting the technical scheme, the anti-hydrolysis agent can improve the stability of the waterborne polyurethane, prevent the waterborne polyurethane from hydrolysis, improve the tensile strength of the first coating layer and further improve the tensile strength of the sandwich aluminum-plated film; when the hydrolysis resistant agent is excessively added, the viscosity of the waterborne polyurethane is increased, the adhesion firmness of the first coating layer and the surface of the BOPET film is reduced, and the heat reflection effect of the sandwich structure aluminum plated film is further influenced.

Preferably, the antioxidant consists of an antioxidant 1076 and an antioxidant 168; the hydrolysis resisting agent is AUSTAB SW-100 or polycarbodiimide.

Through the technical scheme, the antioxidant 1076 can remove free radicals in the water-based polyurethane and prevent chain reaction of a series of free radicals, so that the purpose of preventing the automatic oxidation of the first coating layer is achieved, the antioxidant 168 prevents more free radicals from being generated by decomposing peroxide, and the antioxidant 1076 and the antioxidant 168 have good stability and can protect the first coating layer for a long time and delay the aging of the first coating layer; the anti-hydrolysis agent improves the phenomena of viscosity reduction and cracking of the first coating layer caused by hydrolysis, improves the stability of the first coating layer and further improves the heat reflection effect of the sandwich structure aluminum plating film.

In a second aspect, the application provides a preparation method of a novel sandwich structure aluminizer, which adopts the following technical scheme:

a preparation method of a novel sandwich structure aluminizer comprises the following steps:

s1, sending the aluminum wire to a boat type vacuum evaporation aluminum plating machine with the temperature of 1300-1600 ℃, and forming a first aluminum plating layer on the substrate layer through the boat type vacuum evaporation aluminum plating machine;

s2, introducing oxygen with the purity of more than 99.9% above the evaporation area, and plating alumina on the first aluminum plating layer for multiple times through a boat type vacuum evaporation aluminum plating machine to form an alumina layer;

and S3, stopping introducing the oxygen, and forming a second aluminum-plated layer on the aluminum oxide layer through the boat type vacuum evaporation aluminum plating machine.

By adopting the technical scheme, the boat type vacuum evaporation aluminum plating machine is used for forming the first aluminum plating layer on the basal layer, then the aluminum oxide layer is formed on the surface of the first aluminum plating layer, in order to improve the compactness of the aluminum oxide layer, the aluminum oxide layer is composed of multiple layers of aluminum oxide, and finally the second aluminum layer is formed on the surface of the aluminum oxide layer, so that the aluminum plating film with the sandwich structure of the basal layer/the aluminum layer-the aluminum oxide layer-the aluminum layer is obtained.

Preferably, the preparation method of the substrate layer comprises:

s11, adding the nano silicon dioxide, the antioxidant and the hydrolysis resistant agent into the waterborne polyurethane, and uniformly mixing to obtain a first mixture;

s12, coating the first mixture on the surface of the BOPET film through an air knife coater, and drying to form a first coating layer;

the first aluminum-plated layer is formed on the first coating layer, and the thickness of the first coating layer is 50-80 angstroms.

By adopting the technical scheme, the nano silicon dioxide, the antioxidant and the hydrolysis resisting agent are added into the waterborne polyurethane and uniformly mixed to obtain a first mixture, the first mixture is coated on the BOPET film to form a first coating layer, then a first aluminum plated layer is evaporated on the first coating layer in a vacuum evaporation mode, and the first coating layer can reduce the corrosion phenomenon of the first aluminum plated layer caused by the alkaline cement mortar; the first coating layer is too thin, which increases the risk of corrosion of the first aluminum plating layer, thereby reducing the heat reflectivity of the sandwich aluminum plating film, and the first coating layer is too thick, which results in too long drying time of the first coating layer and influences the adhesion firmness of the first aluminum plating layer on the first coating layer.

Preferably, after step S3 is completed, the method further includes the following steps:

s4, adding potassium silicate into the epoxy resin, uniformly mixing to obtain a second mixture, coating the second mixture on the surface of the second aluminum-plated layer through an air knife coater, and drying to form a second coating layer;

wherein the thickness of the second coating layer is 50-80 angstroms.

By adopting the technical scheme. Coating the second mixture on the surface of the aluminum oxide layer and drying to form a second coating layer, thereby obtaining the novel sandwich-structure aluminizer, wherein the second coating layer can reduce the corrosion phenomenon of the second aluminizer and further improve the corrosion resistance of the sandwich-structure aluminizer; the second coating layer is too thin, which increases the risk of corrosion of the second aluminum plating layer, thereby reducing the heat reflectivity of the sandwich aluminum plating film, and the second coating layer is too thick, which results in too long drying time of the second coating layer and influences the adhesion firmness of the second coating layer on the second aluminum plating layer.

Preferably, the BOPET film and the second aluminum-plated layer are respectively subjected to plasma treatment on the surfaces thereof before the first coating layer and the second coating layer are formed.

By adopting the technical scheme, the surface of the BOPET film is subjected to plasma treatment, and the surface of the film is etched under the combined action of free electrons, ions and active groups in the plasma, so that the roughness of the surface of the BOPET film is further increased, and the adhesion firmness of the first coating layer on the surface of the BOPET film is improved; and the plasma treatment is carried out on the surface of the second aluminum-plated layer, so that the adhesion firmness of the second coating layer on the surface of the second aluminum-plated layer is increased, and the heat reflectivity of the sandwich-structure aluminum-plated film is further improved.

Preferably, the plasma treatment power is 3-10 KW.

By adopting the technical scheme, the roughness of the BOPET film and the surface of the second aluminum-plated layer can be increased by plasma treatment of the BOPET film and the surface of the second aluminum-plated layer, when the plasma treatment power is too small, the roughness of the BOPET film and the surface of the second aluminum-plated layer is insufficient, so that the adhesion firmness between the first coating layer and the BOPET film and the adhesion firmness between the second coating layer and the second aluminum-plated layer are too small, and the heat reflectivity of the aluminum-plated film with the sandwich structure is influenced; when the plasma treatment power is higher, cracks are easily generated on the surface of the BOPET film, so that the tensile strength of the sandwich-structure aluminizer is reduced, the sandwich-structure aluminizer is easy to crack, and the thermal reflectivity of the sandwich-structure aluminizer is influenced.

In summary, the present application has the following beneficial effects:

1. the aluminum plating film with the four-layer sandwich structure of the base layer/the first aluminum plating layer-the aluminum oxide layer-the second aluminum plating layer has the advantages of good heat reflection effect, strong corrosion resistance and high reliability, the aluminum oxide layer reduces the corrosion phenomenon of the second aluminum plating layer, the first aluminum plating layer further prevents water vapor and alkaline cement mortar from reacting with the second aluminum plating layer, and the second aluminum plating layer can be prevented from being corroded by the alkaline cement mortar through the matching of the aluminum oxide layer and the first aluminum plating layer;

2. the waterborne polyurethane in the first coating layer has good adhesive force on the BOPET film, can block the corrosion of water vapor to the first aluminum-plated layer, the nano silicon dioxide can increase the surface roughness of the first coating layer and improve the adhesion firmness of a subsequent coating layer, and the antioxidant and the anti-hydrolysis agent can increase the stability of the base layer and further improve the durability of the sandwich structure aluminum-plated film;

3. the epoxy resin in the second coating layer has better chemical corrosion resistance and heat resistance, and has high adhesive force on metal, and the potassium silicate added into the epoxy resin can improve the high-temperature resistance and corrosion resistance effects of the second coating layer and reduce the corrosion risk of the second aluminum plating layer.

Detailed Description

The present application will be described in further detail with reference to examples.

The information on the raw materials to which this application relates is shown in table 1.

Raw materials	Source
		BOPET film	Shenzhen Yasheng Industrial materials Co Ltd
Aluminum wire	Honyou abrasion-resistant Material Limited of south City
		Aqueous polyurethane	ANHUI ANDA HUATAI NEW MATERIAL Co.,Ltd.
Nano dioxygenSilicon nitride	Micro-nano chemical plant for shou Shi Changtai of Shandong province
		AUSTAB SW-100	Shanghai Long flower chemical Co., Ltd
Polycarbodiimide	Jiangsu Runfeng synthetic science and technology limited
		Antioxidant 1076	Shanghai Kayin chemical Co Ltd
Antioxidant 168	Shanghai Kayin chemical Co Ltd
		Epoxy resin	JINAN LVZHOU COMPOSITE MATERIALS Co.,Ltd.
Potassium silicate	Shandong Kepler Biotech Co., Ltd

Examples

The mixture ratio of the raw materials in examples 1 to 5 of the present invention is shown in Table 2.

Table 2 table of formulation of novel sandwich structure aluminizer of examples 1 to 5

Examples 1 to 5

The novel sandwich structure aluminizer comprises the following components in parts by weight shown in Table 2 and is prepared by the following method:

s1, adding the nano silicon dioxide, the antioxidant and the hydrolysis resistant agent into the waterborne polyurethane, and uniformly mixing to obtain a first mixture;

s2, coating the first mixture on the surface of the BOPET film through an air knife coater, and drying to form a first coating layer;

s3, sending the aluminum wire to a boat type vacuum evaporation aluminum plating machine with the temperature of 1300-1600 ℃, and forming a first aluminum plating layer on the first coating layer through the boat type vacuum evaporation aluminum plating machine;

s4, introducing oxygen with the purity of more than 99.9% above the evaporation area, and plating alumina on the first aluminum plating layer for multiple times through a boat type vacuum evaporation aluminum plating machine to form an alumina layer;

s5, stopping introducing oxygen, and forming a second aluminum-plated layer on the aluminum oxide layer through the boat-type vacuum evaporation aluminum plating machine;

s6, adding potassium silicate into the epoxy resin, uniformly mixing to obtain a second mixture, coating the second mixture on the surface of the second aluminum-plated layer through an air knife coater, and drying to form a second coating layer.

Example 6

A novel sandwich structure aluminizer is different from the aluminizer in example 5 in that the weight of nano silicon dioxide is 5 g.

Example 7

A novel sandwich structure aluminizer is different from the aluminizer in example 5 in that the weight of nano silicon dioxide is 20 g.

Example 8

A novel sandwich structure aluminum-plated film is different from the one in example 5 in that the weight of AUSTAB SW-100 is 0.3 g.

Example 9

A novel aluminum-plated film with a sandwich structure is different from that in example 5 in that the weight of AUSTAB SW-100 is 5 g.

Example 10

A novel sandwich-structured aluminum plated film, which is different from example 5 in that the thickness of the first coating layer was 55 angstroms.

Example 11

A novel sandwich-structured aluminum plated film, which is different from example 5 in that the thickness of the first coating layer was 75 angstroms.

Example 12

A novel aluminum-plated film of a sandwich structure, which is different from example 5 in that the thickness of the first aluminum-plated layer is 250 angstroms.

Example 13

A novel aluminum-plated film of a sandwich structure, which is different from example 5 in that the thickness of the first aluminum-plated layer is 450 angstroms.

Example 14

A novel aluminum-plated film of a sandwich structure, which is different from example 5 in that the thickness of the second aluminum-plated layer is 250 angstroms.

Example 15

A novel aluminum-plated film of a sandwich structure, which is different from example 5 in that the thickness of the second aluminum-plated layer is 450 angstroms.

Example 16

A novel sandwich-structured aluminum plated film, which is different from example 5 in that the thickness of the second coating layer was 55 angstroms.

Example 17

A novel sandwich-structured aluminum plated film, which is different from example 5 in that the thickness of the second coating layer was 75 angstroms.

Comparative example

Comparative example 1

An aluminum-plated film is prepared by the following method:

the aluminum wire is sent to a boat type vacuum evaporation aluminum plating machine with the temperature of 1300-1600 ℃, and an aluminum plating layer with the thickness of 400 angstroms is formed on the BOPET film through the boat type vacuum evaporation aluminum plating machine.

Comparative example 2

An aluminum-plated film is prepared by the following method:

the aluminum wire is sent to a boat type vacuum evaporation aluminum plating machine with the temperature of 1300-1600 ℃, and an aluminum plating layer with the thickness of 200 angstroms is formed on the BOPET film through the boat type vacuum evaporation aluminum plating machine;

introducing oxygen with the purity of more than 99.9 percent into the upper part of the evaporation area, and plating aluminum oxide on the aluminum plating layer for multiple times by a boat type vacuum evaporation aluminum plating machine to form the aluminum oxide layer with the thickness of 1000 angstroms.

Comparative example 3

An aluminum-plated film, which is different from embodiment 1 in that a second aluminum-plated layer is directly formed on an aluminum oxide layer, and the second aluminum-plated layer is not provided with a second coating layer.

Comparative example 4

An aluminum-plated film, which is different from example 1 in that a first aluminum-plated layer is directly formed on a BOPET film without a first coating layer therebetween.

Performance test

The following performance tests were carried out for the sandwich-structured aluminum plating films provided in examples 1 to 17 and comparative examples 1 to 4 of the present application:

breaking force: the aluminized films of examples 1 to 17 and comparative examples 1 to 4 were cut into test specimens having a length of 150mm, a width of 15mm and a gauge length of (100 Shi 1) mm, and all the test specimens were tested according to the regulation of GB/T1040.3-2006, 5 test specimens were respectively used for the tensile strength test of each example and comparative example, the tensile strength test was carried out according to the regulation of GB/T1040.3-2006, and the test results were averaged, wherein the tensile speed (no load) of the test specimens was (250 Shi 25) mm/min, and the tensile strength was rated as follows according to GB/T21302-2007 "composite film for packaging, bag on rule":

1 grade-breaking force (N/15mm) > 100;

2-grade-50-100 of breaking force (N/15 mm);

3 grade-25 is less than or equal to the breaking force (N/15mm) < 50;

4-grade, the breaking force (N/15mm) is more than or equal to 5 and less than 25;

5 grade-breaking force (N/15mm) < 5.

Coating film layer adhesion firmness: the aluminized films of examples 1 to 17 and comparative examples 1 to 4 were cut into 50mm by 200mm test samples, a Scotch brand 610 pressure-sensitive adhesive tape from 3M company was used, an adhesive tape having a width of 25mm and a length of 150mm was attached to the aluminized surface and pressed flat with fingers, then the sample was pressed with one hand, the adhesive tape was peeled off with the other hand at a constant speed in a direction of 180 ° at a constant speed, a lamp box with strong light was used to examine the peeling and transfer condition of the aluminum layer, the peeling area was calculated, 5 test samples were taken for each example and comparative example, the test results were averaged, and it was found that the glass area was not more than 15%.

And (3) testing the heat reflectivity: the aluminized films of examples 1 to 17 and comparative examples 1 to 4 were cut into 6cm by 6cm test samples, and the infrared heat reflectivities of the samples were collected using an FTIR-FTS3000 spectrometer and a diffuse reflection accessory, 5 test samples were taken for each example and comparative example, and the test results were averaged.

And (3) aging test: the aluminizers of examples 1 to 17 and comparative examples 1 to 4 were cut into 200mm by 200mm test samples, the test samples were placed in a constant temperature and humidity chamber at 65 ℃ and 90% RH for aging test, after 200 hours, the corrosion of the test samples was observed and the infrared heat reflectance and the breaking force were measured, and 5 test samples were taken for each example and comparative example, and the results were averaged.

The specific test results are shown in table 3.

Table 3 results of performance testing

It can be seen from the comparison of the data in examples 1 to 17 and comparative examples 1 to 4 that the sandwich-structured aluminum-plated film prepared by the substrate layer, the first coating layer, the first aluminum-plated layer, the aluminum oxide layer, the second aluminum-plated layer and the second coating layer interacts with each other layer by layer, and finally the purpose of improving the thermal reflectivity of the aluminum-plated film is achieved. Specifically, the aluminum-plated film in comparative example 1 is formed by directly evaporating an aluminum-plated layer with a thickness of 400 angstroms on the BOPET film, the total thickness of the first aluminum-plated layer and the second aluminum-plated layer of the novel sandwich structure aluminum-plated film in example 1 is 400 angstroms, and under the condition that the total thickness of the aluminum-plated layers is the same, the novel sandwich structure aluminum-plated film in example 1 reduces the possibility that the aluminum-plated layer is corroded due to the protection of the first aluminum-plated layer and the second aluminum-plated layer by the alumina layer, the first coating layer and the second coating layer, and enhances the stability and the heat reflectivity of the novel sandwich structure aluminum-plated film.

The aluminum plated film of comparative example 2 also directly forms an aluminum oxide layer having a thickness of 1000 a on the aluminum plated layer, and although the aluminum plated layer can be protected, the aluminum plated film of comparative example 2 has a poor heat reflection effect than the aluminum plated layer, and the aluminum plated layer of comparative example 2 has a poor aging resistance due to easy corrosion by alkali cement mortar, compared to the novel sandwich-structured aluminum plated film of example 1, although the total thickness of the aluminum plated layer is the same and the thickness of the aluminum oxide layer is also the same, while the first and second aluminum plated layers of example 1 are protected by the first coating layer, the aluminum oxide layer and the second coating layer and are not easily corroded, and thus the stability and heat reflectivity of the novel sandwich-structured aluminum plated film are good.

According to the comparison of the experimental data of the example 1 and the comparative examples 1-4, the first coating layer can improve the adhesion firmness of the coating layer on the substrate layer; the aluminum oxide layer is plated for multiple times, so that the compactness of the aluminum oxide layer can be improved, and the corrosion of the second aluminum plated layer by the alkaline mortar is further reduced; the second aluminum-plated layer can effectively improve the heat reflectivity of the aluminum-plated film with the sandwich structure; the second coating layer effectively reduces the possibility of corrosion of the second aluminum plating layer, and further improves the heat reflectivity of the sandwich aluminum plating film.

From the comparison of the experimental data of example 5 and examples 6-9, it can be seen that the nano-silica in the first coating layer can increase the surface roughness of the first coating layer, and when the amount of the nano-silica is too small, the surface roughness of the first coating layer is too small, and the adhesion firmness between the first aluminum-plated layer and the first coating layer is weakened; when the addition amount of the nano silicon dioxide is too large, the surface roughness of the first coating layer is too large, so that the first aluminum-plated layer cannot fill the depression on the surface of the first coating layer, and the adhesion firmness between the first aluminum-plated layer and the first coating layer is further reduced; when the addition amount of the hydrolysis resistant agent is too small, the effect of improving the stability of the substrate layer is not good, and when the addition amount of the hydrolysis resistant agent is too large, the viscosity of the first coating layer is increased, and the adhesion firmness between the first coating layer and the BOPET film is reduced.

From the comparison of the experimental data of example 5 with examples 10-11, it can be seen that the thinner the first coating layer is, the greater the risk of corrosion of the first aluminized layer, thereby reducing the thermal reflectance of the sandwich aluminized film; the thicker the first coating layer, the longer the drying time of the first coating layer, which in turn affects the adhesion robustness of the first aluminum plating layer on the first coating layer.

As can be seen from comparison of the experimental data in the embodiment 5 and the embodiments 12 to 15, the corrosion resistance and the heat reflectivity of the sandwich aluminum plated film are easily reduced due to the excessively thin first aluminum plated layer and the second aluminum plated layer, the toughness of the first aluminum plated layer and the second aluminum plated layer is reduced due to the excessively thick first aluminum plated layer and the second aluminum plated layer, and the first aluminum plated layer and the second aluminum plated layer are likely to generate stress concentration and cracks in practical application, thereby reducing the tensile strength of the sandwich aluminum plated film and affecting the heat reflectivity of the sandwich aluminum plated film.

From the comparison of the experimental data of example 5 and examples 16-17, it can be seen that the first coating layer is too thin, which increases the risk of corrosion of the first aluminum plating layer, thereby reducing the heat reflectivity of the sandwich aluminum plating film, and the first coating layer is too thick, which results in too long drying time of the first coating layer and affects the adhesion firmness of the first aluminum plating layer on the first coating layer; the second coating layer is too thin, which increases the risk of corrosion of the second aluminum plating layer, thereby reducing the heat reflectivity of the sandwich aluminum plating film, and the second coating layer is too thick, which results in too long drying time of the second coating layer and influences the adhesion firmness of the second coating layer on the second aluminum plating layer.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims

1. The sandwich structure aluminum-plated film is characterized by being of a four-layer sandwich structure of a substrate layer/an aluminum layer-an aluminum oxide layer-an aluminum layer and comprising the substrate layer, a first aluminum-plated layer plated on the substrate layer, the aluminum oxide layer plated on the first aluminum-plated layer and a second aluminum-plated layer plated on the aluminum oxide layer;

the thickness of the first aluminum plating layer is 200-500 angstroms, the thickness of the aluminum oxide layer is 1000-2000 angstroms, and the thickness of the second aluminum plating layer is 200-500 angstroms;

the base layer comprises a BOPET film and a first coating layer coated on the BOPET film, wherein the first coating layer is prepared from the following raw materials in parts by weight:

50-250 parts of waterborne polyurethane;

10-15 parts of nano silicon dioxide;

0.5-3 parts of hydrolysis resistant agent;

0.1-1.5 parts of antioxidant;

the surface of the second aluminum-plated layer is coated with a second coating layer, and the second coating layer is prepared from the following raw materials in parts by weight:

8-10 parts of epoxy resin;

1-4 parts of potassium silicate.

2. The sandwich aluminum plated film according to claim 1, wherein: the mass ratio of the hydrolysis resistant agent to the waterborne polyurethane is (0.5-2%) to 1.

3. The sandwich structure aluminum plated film according to claim 1, wherein: the antioxidant consists of an antioxidant 1076 and an antioxidant 168; the hydrolysis resisting agent is AUSTAB SW-100 or polycarbodiimide.

4. A method for producing a sandwich structure aluminum plated film for use in producing the sandwich structure aluminum plated film according to any one of claims 1 to 3, comprising the steps of:

and S3, stopping introducing the oxygen, and forming a second aluminum plating layer on the aluminum oxide layer through the boat type vacuum evaporation aluminum plating machine.

5. The method for preparing a sandwich structure aluminizer according to claim 4, wherein the base layer is prepared by:

6. The method for preparing the sandwich structure aluminizer according to claim 5, further comprising the following steps after completion of the step S3:

wherein the thickness of the second coating layer is 50-80 angstroms.

7. The method of claim 6, wherein the BOPET film and the second aluminum-plated layer are respectively plasma-treated on the surfaces thereof before the first coating layer and the second coating layer are formed.

8. The method for preparing a sandwich structure aluminum plating film according to claim 7, wherein the plasma treatment power is 3-10 KW.