CN116355515A

CN116355515A - Application of water-based strippable paint

Info

Publication number: CN116355515A
Application number: CN202310473721.3A
Authority: CN
Inventors: 朱建光; 龙伟; 张浩明
Original assignee: Jiangsu Osic Material Technology Co ltd
Current assignee: Jiangsu Osic Material Technology Co ltd
Priority date: 2021-12-29
Filing date: 2021-12-29
Publication date: 2023-06-30
Also published as: CN114181604B; CN114181604A

Abstract

The invention provides an application of water-based strippable paint. The method comprises the steps of coating water-based strippable paint on a substrate, and drying at 50-80 ℃ to obtain a paint film, wherein the thickness of the paint film is 50-70 mm; the raw material components of the water-based strippable paint comprise 15-95% of water-based polyurethane dispersoid, 0-80% of water-based polyolefin emulsion, 0.5-5% of cross-linking agent and 0-5% of color paste according to weight percentage; wherein polyurethane in the aqueous polyurethane dispersion is aliphatic polyurethane, and the cross-linking agent is polycarbodiimide. The water-based strippable paint has the advantages of simple formula, alkali resistance, water resistance and good strippability.

Description

Application of water-based strippable paint

Technical Field

The invention relates to application of water-based strippable paint.

Background

The strippable paint is a temporary protective paint, is coated on various base materials through different construction methods, protects the base materials, avoids the defects of scratch, aging, poor appearance, color loss and the like on the surface of the base materials, can be stripped smoothly after a certain protection period is completed, and can restore the original appearance and performance of the product without generating adverse effects on the surface of the base materials.

At present, the strippable paint is easy to tear during stripping, cannot be stripped off in whole, or has the defect that stripping aids such as organic silicon, surfactant and the like are required to be added for assisting stripping, and the addition of the stripping aids can adhere to the surface of a substrate to cause poor appearance. In addition, the existing strippable paint has poor water resistance and alkali resistance.

Disclosure of Invention

The invention aims to provide water-based strippable paint with good water resistance, alkali resistance and strippability and a preparation method thereof.

In order to achieve the above purpose, the invention adopts the following technical scheme:

an aqueous strippable paint, the raw material components of which comprise an aqueous polyurethane dispersion and a cross-linking agent, wherein the polyurethane in the aqueous polyurethane dispersion comprises aliphatic polyurethane, and the cross-linking agent comprises polycarbodiimide.

Preferably, the dosage of the cross-linking agent is 0.1-10% of the total weight of the raw material components of the water-based strippable paint.

Further preferably, the dosage of the cross-linking agent is 0.5-5% of the total weight of the raw material components of the water-based strippable paint.

Preferably, the aqueous polyurethane dispersion has a solids content of 30 to 50%.

Preferably, the raw material components of the water-based strippable paint further comprise water-based polyolefin emulsion and/or color paste.

Further preferably, the aqueous polyolefin emulsion has a solids content of 20 to 40% and a particle size of less than 0.2. Mu.m.

Preferably, the raw material components of the water-based strippable paint comprise, in weight percent:

further preferably, the raw material components of the aqueous strippable paint include:

according to some preferred modes, the color paste comprises the following components in percentage by weight:

preferably, the defoamer comprises one or more of a silicone defoamer, a composite silicone defoamer, and an acetylenic diol defoamer.

Preferably, the dispersant comprises one or more of polyurethane, polyacrylate, phosphate.

Preferably, the blue powder comprises one or more of phthalocyanine blue 15:1 and phthalocyanine blue 15:3.

Preferably, the germicides include isothiazolinone germicides.

Further preferably, the isothiazolinone bactericide comprises one or more of 2-methyl-4-isothiazolin-3-one (CIT), 1-2 benzisothiazolin-3-one (BIT), methyl Chloroisothiazolinone (CMIT) and Methyl Isothiazolinone (MIT).

Preferably, the neutralizing agent comprises one or more of dimethylethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol.

In another aspect of the present invention, a method for preparing an aqueous strippable paint is provided, in which an aqueous polyurethane dispersion is added to a container, an aqueous polyolefin emulsion is selectively added to the container while stirring, and then a crosslinking agent and a color paste are added to the container.

Further preferably, the stirring speed is controlled to 500 to 800rpm/min.

In a third aspect of the invention there is provided the use of an aqueous strippable paint comprising applying said aqueous strippable paint to a substrate and drying to give a paint film.

Preferably, the thickness of the paint film is 10 to 100mm.

Further preferably, the thickness of the paint film is 30 to 80mm.

Still more preferably, the thickness of the paint film is 50 to 70mm.

Preferably, it is dried at 50 to 80 ℃.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

the water-based strippable paint has the advantages of simple formula, alkali resistance, water resistance and good strippability; the preparation method of the water-based strippable paint has the advantages of simple preparation steps, easy control and excellent performance of the prepared water-based strippable paint.

Detailed Description

The existing strippable paint has the defects of poor water resistance and alkali resistance, easy tearing during stripping, incapability of complete stripping, or the need of adding stripping aids such as organic silicon, surfactants and the like to assist stripping.

Based on the shortcomings of the prior art, the applicant has obtained the scheme of the application through long-term experiments and a great deal of research, and the scheme is further described below.

The water-based strippable paint comprises the raw material components of a water-based polyurethane dispersion and a cross-linking agent, wherein polyurethane in the water-based polyurethane dispersion comprises aliphatic polyurethane, and the cross-linking agent comprises polycarbodiimide.

In the present invention, the solid content of the aqueous polyurethane dispersion is 30 to 50%, and may be, for example, 30%, 35%, 40%, 45%, 50%, or the like.

In the present invention, the solid content of the crosslinking agent polycarbodiimide is 30 to 50%, and may be, for example, 30%, 35%, 40%, 45%, 50%, or the like. The polycarbodiimide can crosslink the aqueous polyurethane dispersion containing carboxyl groups, and improve water resistance and strength. The dosage of the cross-linking agent is 0.1-10% of the total weight of the raw material components of the water-based strippable paint. When the feeding amount of the cross-linking agent is larger than a certain range, the prepared water-based strippable paint is difficult to strip and cannot meet the strippable requirement. According to the preferred embodiment, the amount of the crosslinking agent added is 0.5 to 5% by weight based on the total weight of the raw material components of the aqueous strippable paint, and may be, for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5% or the like.

Further, the raw material components of the water-based strippable paint also comprise water-based polyolefin emulsion and/or color paste. The aqueous strippable paint prepared by compounding the aqueous polyolefin emulsion and the aqueous polyurethane dispersion has better strippable property, water resistance, alkali resistance and the like. Wherein the solid content of the aqueous polyolefin emulsion is 20-40%, for example, 20%, 25%, 30%, 35%, 40%, etc.; the particle size is less than 0.2 μm.

The water-based strippable paint provided by the invention is transparent in color, and the color desired by a user can be obtained by adding color paste. The color paste can be commercial color paste or homemade color paste, and the homemade color paste is adopted in the invention. The self-made color paste comprises the following components in percentage by weight:

wherein the defoamer comprises one or more of organosilicon defoamer, composite organosilicon defoamer and alkyne diol defoamer, and the organosilicon defoamer comprises but is not limited to an Osic-F1301 defoamer. The dispersant includes one or more of polyurethane, polyacrylate, and phosphate, such as, for example, osic-dis2130. The blue powder comprises one or more of phthalocyanine blue 15:1 and phthalocyanine blue 15:3, such as one or more of south general contention for phthalocyanine blue BGS and solar chemical Fast 0061. The germicides include one or more of CMIT/MIT, BIT, BIT/MIT, for example, huffman Defors BT. The neutralizing agent comprises one or more of dimethylethanolamine, monoisopropanolamine and 2-amino-2-methyl-1-propanol.

The preparation method of the color paste comprises the steps of pouring weighed water, a defoaming agent and a dispersing agent into a container, premixing for 5 minutes at the rotating speed of 600rpm/min, adding other component materials, and mixing for 15 minutes at the rotating speed of 1200rpm/min to obtain evenly distributed premix paste. Adding grinding medium into a container according to the standard (premix slurry: glass bead volume ratio=1:1), grinding and dispersing the premix slurry, and filtering to obtain color paste.

In some preferred embodiments, the aqueous strippable paint comprises, in weight percent:

in other preferred embodiments, the aqueous strippable paint comprises, in weight percent:

wherein the mass ratio of the aqueous polyurethane dispersion can be 18%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc. The mass ratio of the aqueous polyolefin emulsion may be 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, etc. The mass ratio of the crosslinking agent may be 0.5%, 1%, 2%, 3%, 4%, 5%, etc.

A process for preparing water-based strippable paint includes such steps as adding aqueous polyurethane dispersion to container, stirring, selectively adding aqueous polyolefm emulsion to container, and adding cross-linking agent and colour paste. The stirring speed is controlled to 500 to 800rpm/min, and may be, for example, 500rpm/min, 550rpm/min, 600rpm/min, 650rpm/min, 700rpm/min, 750rpm/min, 800rpm/min, etc.

The invention is further described below with reference to examples. The present invention is not limited to the following examples. The implementation conditions adopted in the embodiments can be further adjusted according to different requirements of specific use, and the implementation conditions which are not noted are conventional conditions in the industry. The technical features of the various embodiments of the present invention may be combined with each other as long as they do not collide with each other.

The raw materials used in the following examples and comparative examples are all commercially available.

The aqueous polyurethane dispersion PUD-1 is an aliphatic polyurethane aqueous polyurethane dispersion, the solid content of which is 40%, and is purchased from honeycomb nanotechnology Co., ltd, and the brand name is 728-A8161;

the aqueous polyurethane dispersion PUD-2 is a polyether polyurethane aqueous polyurethane dispersion, the solid content of which is 50%, and is purchased from Kogyo Ind polymer (China) Co., ltd., brand Bayhydrol UH2880;

the aqueous polyurethane dispersion PUD-3 is an epoxy modified aliphatic polyurethane aqueous polyurethane dispersion, the solid content of which is 35%, and is purchased from Shanghai Limited of Ding Material science and technology, and the brand DYR8829;

polycarbodiimide, available from Jiangsu austia materials technologies Co., ltd., brand GX-3;

the aqueous polyolefin emulsion was purchased from Shanghai, inc., ZAIKTHENE AC;

the aqueous polyacrylic emulsion is purchased from Nanjing Gutian chemical Co., ltd, and the brand name is Bai Zhi Mo PC-25;

polyethylenimine is available from Shanghai Gao New Material technologies Co., ltd, brand JD-100;

the aqueous polyisocyanate was purchased from Jiangsu austia materials technologies Co., ltd., brand NE533.

Example 1

Weighing 100g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 5g of polycarbodiimide and 1g of self-grinding paste, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

The prepared water-based strippable paint is coated on a transparent polyester PET film, dried at 70 ℃ for 5min, and subjected to standing for 24h, and the performance is tested, wherein the thickness of a dried paint film is 50mm.

Example 2

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 80g of aqueous polyolefin emulsion, 1g of polycarbodiimide and 2g of self-grinding paste, adding each raw material while stirring, adding the raw materials for 2min, and stirring for 15min after all the raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Example 3

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 80g of aqueous polyolefin emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Example 4

Weighing 50g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 50g of aqueous polyolefin emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Example 5

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 1g of polycarbodiimide and 80g of aqueous polyolefin emulsion, adding for 2min, stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Example 6

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 5g of polycarbodiimide and 80g of aqueous polyolefin emulsion, adding for 2min, stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Example 7

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 10g of polycarbodiimide and 80g of aqueous polyolefin emulsion, adding for 2min, stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Example 8

100g of aqueous polyurethane dispersoid PUD-1 is weighed into a container, stirred and dispersed by a stirring and dispersing machine at the stirring speed of 700-800rpm/min, 1g of polycarbodiimide is added, the adding process is carried out for 2min, and the mixture is stirred for 15min after all the raw materials are added, so that the aqueous strippable paint is prepared.

Example 9

100g of aqueous polyurethane dispersoid PUD-1 is weighed into a container, stirred and dispersed by a stirring and dispersing machine at the stirring speed of 700-800rpm/min, 10g of polycarbodiimide is added, the adding process is carried out for 2min, and the stirring is carried out for 15min after all the raw materials are added, so that the aqueous strippable paint is prepared.

Example 10

The prepared water-based strippable paint is coated on a transparent polyester PET film, dried at 70 ℃ for 5min, and subjected to standing for 24h, and the performance is tested, wherein the thickness of a dried paint film is 30mm.

Example 11

The prepared water-based strippable paint is coated on a transparent polyester PET film, dried at 70 ℃ for 5min, and subjected to standing for 24h, and the performance is tested, wherein the thickness of a dried paint film is 75mm.

Comparative example 1

Weighing 100g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 5g of cross-linking agent polyethylenimine and 1g of self-grinding paste, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 2

Weighing 100g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 5g of cross-linking agent aqueous polyisocyanate and 1g of self-grinding paste, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 3

Weighing 100g of aqueous polyacrylic emulsion into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 1g of self-grinding paste, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 4

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800/min by a stirring and dispersing machine, sequentially adding 80g of aqueous polyacrylic emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

The prepared water-based strippable paint is coated on a transparent polyester PET film, dried at 70 ℃ for 5min, and subjected to standing for 24h, the performance is tested, and the thickness of a dried paint film is 50mm.

Comparative example 5

Weighing 20g of aqueous polyolefin emulsion into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 80g of aqueous polyacrylic emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 6

Weighing 50g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 50g of aqueous polyacrylic emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 7

Weighing 50g of aqueous polyolefin emulsion into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 50g of polyacrylic emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 8

Weighing 100g of aqueous polyurethane dispersoid PUD-2 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 5g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 9

Weighing 100g of aqueous polyurethane dispersoid PUD-3 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 5g of polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 10

Weighing 20g of aqueous polyurethane dispersoid PUD-2 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 80g of aqueous polyolefin emulsion and 1g of cross-linking agent polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 11

Weighing 20g of aqueous polyurethane dispersoid PUD-3 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 80g of aqueous polyolefin emulsion and 1g of cross-linking agent polycarbodiimide, adding each raw material while stirring, adding for 2min, and stirring for 15min after all raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 12

Weighing 20g of aqueous polyurethane dispersoid PUD-1 into a container, stirring and dispersing at a stirring speed of 700-800rpm/min by a stirring and dispersing machine, sequentially adding 20g of aqueous polyolefin emulsion, 60g of aqueous polyacrylic emulsion and 1g of polycarbodiimide, adding each raw material while stirring, adding the raw materials for 2min, and stirring for 15min after all the raw materials are added, and uniformly mixing to obtain the aqueous strippable paint.

Comparative example 13

40g of aqueous polyurethane dispersoid PUD-1 is weighed into a container, a stirring and dispersing machine is used for stirring and dispersing at the stirring speed of 700-800rpm/min, 40g of aqueous polyolefin emulsion, 20g of aqueous polyacrylic emulsion and 1g of polycarbodiimide are sequentially added, each raw material is added while stirring, the adding process is carried out for 2min, and after all the raw materials are added, stirring is carried out for 15min, and the aqueous strippable paint is prepared.

The raw materials and the addition amounts thereof in the above examples and comparative examples are shown in table 1 below.

TABLE 1

The performance test data for each example and comparative example are shown in table 2 below.

TABLE 2

Colorability of the ink

Tailorability of cutting

Strippability of

Water resistance

Alkali resistance

Peel force

Example 1

By passing through

R1

Example 2

By passing through

R2

Example 3

—

By passing through

R2

Example 4

—

By passing through

R2

Example 5

—

By passing through

R2

Example 6

—

By passing through

R2

Example 7

—

By passing through

Not pass through

By passing through

/

Example 8

—

By passing through

R1

Example 9

—

By passing through

Not pass through

By passing through

/

Example 10

By passing through

Not pass through

By passing through

/

Example 11

Not pass through

By passing through

R1

Comparative example 1

By passing through

Not pass through

/

Comparative example 2

By passing through

Not pass through

/

Comparative example 3

Not pass through

By passing through

Not pass through

/

Comparative example 4

—

Not pass through

/

Comparative example 5

—

Not pass through

/

Comparative example 6

—

Not pass through

/

Comparative example 7

—

Not pass through

/

Comparative example 8

—

By passing through

Not pass through

/

Comparative example 9

—

By passing through

Not pass through

/

Comparative example 10

—

By passing through

Not pass through

/

Comparative example 11

—

By passing through

Not pass through

/

Comparative example 12

—

Not pass through

/

Comparative example 13

—

Not pass through

/

In Table 2, "-" indicates that the coloring property was not required in the case where no color paste was added to the formulation. "/" indicates that no peel force test was performed in the case where the result in the formulation was non-peelable.

The treatment of the PET substrates and the treatment of the comparative PET substrates and the application and curing of the strippable paint are as follows:

(1) The polyester PET film is selected as a base material of the water-based strippable paint, the disposable butyronitrile gloves are worn by both hands, a small amount of 30% alcohol solution is dipped in non-woven fabrics, the surface of the polyester film is gently wiped, and the polyester film is placed in a clean environment for standby.

(2) The aqueous stripping paint was coated on a polyester PET film sheet using a wet film preparation machine, and the coated preparation machine was washed with clear water and alcohol.

(3) And (3) placing the polyester film sheet coated with the water-based stripping paint in an electric heating oven, curing at a low temperature according to a program, finally taking out the film sheet, standing and cooling to obtain a PET sheet decorated by the stripping paint, and carrying out the performance test of the next step after the sheet is kept for 24 hours.

The performance test method comprises the following steps:

(1) Colorability test

The polyester PET sheet coated with the release paint was faced to the reference object, and the clarity of the reference object was observed.

(2) Tailorability test

The polyester PET sheet coated with the release paint was cut with a paper cutter, and the degree of coating adhesion at the cut edge was observed.

(3) Strippability test

The coating was peeled off from the PET and the PET substrate was observed for coating residue, as well as the integrity of the coating peeling.

(4) Water resistance test

And (3) placing the plate to be tested coated with the stripping paint into a constant-temperature water tank, soaking the plate in hot water at 50 ℃ for 1 hour, taking out the plate to observe the appearance of the stripping paint, and removing and bubbling the coating after being heated.

(5) Alkali resistance test

Shaking up the calcium hydroxide solution by using an oscillator HY-4, placing the alkaline solution into a container after 30 minutes, testing the solution to be weak alkaline by using a PH meter, placing the plate to be tested coated with the stripping paint into the container, soaking for 1 hour, and taking out the plate to observe the appearance of the stripping paint, and the shedding and bubbling degree of the coating.

(6) Peel force test:

one end of the stripping film is pre-pulled out and connected, one end of the stripping film is fixed by a clamp and is vertically placed, the stripping film is pulled down at a specified speed of 180 degrees, the pulling force at the moment is measured, and R3 is smaller than R2 and smaller than R1 are respectively represented by the grades on the premise of stripping.

The pass and fail criteria for each of the above properties are shown in Table 3 below.

TABLE 3 Table 3

Sequence number	Project	By passing through	Not pass through
				1	Colorability of the ink	Transparent, uniform	Turbidity, inhomogeneity
2	Tailorability of cutting	Cutting edge coating adhesion	The cut edge coating is not tight
				3	Strippability of	Tearing by hand, no residue on substrate	Tearing by hand, residue on substrate
4	Water resistance	The coating does not fall off, bubbling and blushing	Coating layer is peeled off, bubbling and whitening
				5	Alkali resistance	The coating does not fall off, bubbling and blushing	Coating layer is peeled off, bubbling and whitening

The present invention has been described in detail with the purpose of enabling those skilled in the art to understand the contents of the present invention and to implement the same, but not to limit the scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of the present invention.

Claims

1. An application of water-based strippable paint, which is characterized in that: the application comprises the steps of coating the water-based strippable paint on a substrate, and drying at 50-80 ℃ to obtain a paint film, wherein the thickness of the paint film is 50-70 mm;

the water-based strippable paint comprises the following raw material components in percentage by weight:

the polyurethane in the aqueous polyurethane dispersion is aliphatic polyurethane, and the cross-linking agent is polycarbodiimide.

2. The use according to claim 1, characterized in that: the paint film cutting edge coating is closely adhered; tearing the paint film, and leaving no residue on the base material; placing the paint film and the base material into a constant-temperature water tank, and soaking in hot water bath at 50 ℃ for 1 hour, wherein the paint film does not fall off, bubbling and blushing; and placing the paint film and the base material into alkali liquor, wherein the paint film is not fallen off, bubbling and blushing after being soaked for 1h, and the alkali liquor is calcium hydroxide solution.

3. The use according to claim 1, characterized in that: the solid content of the aqueous polyurethane dispersion is 30-50%.

4. The use according to claim 1, characterized in that: the solid content of the aqueous polyolefin emulsion is 20-40%, and the particle size is less than 0.2 mu m.

5. The use according to claim 1, characterized in that: the water-based strippable paint comprises the following raw material components in percentage by weight:

6. the use according to claim 1, characterized in that: the preparation method of the water-based strippable paint comprises the steps of adding the water-based polyurethane dispersion into a container, selectively adding the water-based polyolefin emulsion into the container in a stirring state, and then adding the cross-linking agent and the color paste into the container.

7. The use according to claim 1, characterized in that: the color paste comprises the following components:

8. the use according to claim 7, characterized in that: the defoaming agent comprises one or more of an organosilicon defoaming agent, a composite organosilicon defoaming agent and an alkyne diol defoaming agent;

and/or the dispersing agent comprises one or more of polyurethane, polyacrylate and phosphate;

and/or the blue powder comprises one or more of phthalocyanine blue 15:1 and phthalocyanine blue 15:3;

and/or, the germicides include isothiazolinone germicides;

and/or the neutralizing agent comprises one or more of dimethylethanolamine, monoisopropanolamine and 2-amino-2-methyl-1-propanol.

9. The use according to claim 8, characterized in that: the organic silicon defoamer comprises an Osic-F1301 defoamer;

the dispersant includes, for example, an aromatic-dis 2130 dispersant;

the blue powder comprises south-through contention-based phthalocyanine blue BGS and/or solar chemistry Fast 0061;

the isothiazolinone bactericide comprises one or more of 2-methyl-4-isothiazolin-3-one, 1-2 benzisothiazolin-3-one, methyl chloroisothiazolinone and methyl isothiazolinone.

10. The use according to claim 7, characterized in that: the preparation method of the color paste comprises the steps of pouring weighed water, a defoaming agent and a dispersing agent into a container, premixing for 5 minutes at the rotating speed of 600rpm/min, adding other component materials, mixing for 15 minutes at the rotating speed of 1200rpm/min to obtain evenly distributed premix slurry, and mixing a grinding medium with the premix slurry: adding the glass beads into a container according to the volume ratio of 1:1, grinding and dispersing the premixed slurry, and filtering to obtain the color paste.