CN112457733B

CN112457733B - Adhesive for laser electrochemical aluminum coating and preparation method thereof

Info

Publication number: CN112457733B
Application number: CN202011332408.0A
Authority: CN
Inventors: 苏苗钢; 杨勇; 朱升
Original assignee: Guangdong Laser Optronics Technology Co ltd
Current assignee: Guangdong Laser Optronics Technology Co ltd
Priority date: 2020-11-24
Filing date: 2020-11-24
Publication date: 2021-11-30
Anticipated expiration: 2040-11-24
Also published as: CN112457733A

Abstract

The invention relates to the technical field of electrochemical aluminum hot stamping, in particular to an adhesive for laser electrochemical aluminum paint and a preparation method thereof. The raw materials for preparing the adhesive comprise resin and a diluent; the invention provides an adhesive, which uses resin and a plasticizer with certain content as an adhesive material, when the adhesive is used for bonding a laser electrochemical aluminum coating and a substrate with varnish, a diluent can be volatilized rapidly, the resin and the plasticizer are uniformly wetted between the coating and the substrate, and form high adhesive force with the electrochemical aluminum coating and the varnish, so that the adhesive force between the electrochemical aluminum coating and the varnish can be increased, and the coating can be prevented from falling off or peeling off; the applicant finds that the complete and bright pattern can be printed by selecting proper resin and plasticizer, the edge of the pattern is clear, and the cutting performance is good.

Description

Adhesive for laser electrochemical aluminum coating and preparation method thereof

Technical Field

The invention relates to the technical field of electrochemical aluminum hot stamping, in particular to an adhesive for laser electrochemical aluminum paint and a preparation method thereof.

Background

Alumite is a hot stamping material prepared by coating and vacuum evaporation coating a layer of metal foil on a film base. The laser alumite is subjected to laser mould pressing on the coloring layer, so that the thermoprinting pattern has flowing rainbow effect, strong metallic luster and three-dimensional sense, is widely applied to the printing and packaging industry, and is rapidly popularized in the industries of food, medicine, daily chemical products, cigarettes, wines, clothing, gift packaging, decorative materials and the like.

The principle of the hot stamping process is as follows: the hot stamping plate is heated to 100-150 ℃, a film material in contact with the hot stamping plate is heated, the melting adhesion force of the stripping layer is reduced firstly, then the gum layer is also melted to generate the adhesion force, the gum layer is firmly adhered to the printing stock under the pressure of 5-8 atmospheric pressures, the coloring layer is separated from the film base layer, and the aluminized layer and the coloring layer are remained on the printing stock. The alumite transferred to the printing stock by the hot stamping forms exquisite pattern characters on the surface of the base material according to the shape of the hot stamping plate.

The existing hot stamping effect is related to a back glue layer formed by bonding a laser alumite coating and a base material besides a hot stamping process, and due to the fact that UV gloss oil is commonly used on the outer layer of the base material such as a plastic packaging box at present, the combination of the laser alumite and the UV gloss oil can greatly improve the grade and the anti-counterfeiting effect of a product. However, the matching between the existing laser electrochemical aluminum coating and the UV varnish on the substrate is poor, so that the laser coating is easy to scrape and fall off, and the problems of blurred patterns or unclear cutting and the like are easily caused, so that research on the adhesive used for the back adhesive layer contacting the laser electrochemical aluminum coating and the varnish is needed.

Disclosure of Invention

In order to solve the above problems, a first aspect of the present invention provides an adhesive prepared from raw materials including a resin and a diluent;

the resin comprises at least two of acrylate resin, polyurethane resin, polyester resin and vinyl chloride-vinyl acetate resin, and accounts for 15-30 wt% of the adhesive.

As a preferable technical scheme of the invention, the resin comprises acrylate resin and polyester resin, and the weight ratio is (1.1-2): 1.

as a preferable technical scheme of the invention, the glass transition temperature of the acrylic resin is 60-80 ℃.

In a preferred embodiment of the present invention, the glass transition temperature of the polyester resin is 60 to 70 ℃.

In a preferred embodiment of the present invention, the polyester resin has a weight average molecular weight of 7000 to 10000.

As a preferable technical scheme of the invention, the preparation raw material of the adhesive also comprises a plasticizer, and the plasticizer is selected from one or more of epoxidized soybean oil, white mineral oil, chlorinated paraffin, castor oil and dioctyl phthalate.

As a preferable technical solution of the present invention, the weight ratio of the plasticizer to the resin is 1: (1.5-2.5).

As a preferable technical scheme of the invention, the chlorine content of the chlorinated paraffin is 50-75 wt%.

The second aspect of the invention provides a preparation method of the adhesive, which comprises the following steps: and mixing the preparation raw materials of the adhesive to obtain the adhesive.

The invention also provides an application of the adhesive in laser electrochemical aluminum paint.

Compared with the prior art, the invention has the following beneficial effects: the invention provides an adhesive, which uses resin and a plasticizer with certain content as an adhesive material, when the adhesive is used for bonding a laser electrochemical aluminum coating and a substrate with varnish, a diluent can be volatilized rapidly, the resin and the plasticizer are uniformly wetted between the coating and the substrate, and form high adhesive force with the electrochemical aluminum coating and the varnish, so that the adhesive force between the electrochemical aluminum coating and the varnish can be increased, and the coating can be prevented from falling off or peeling off; the applicant finds that the complete and bright pattern can be printed by selecting proper resin and plasticizer, the edge of the pattern is clear, and the cutting performance is good.

Detailed Description

The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.

The term "prepared from …" as used herein is synonymous with "comprising". The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

The conjunction "consisting of …" excludes any unspecified elements, steps or components. If used in a claim, the phrase is intended to claim as closed, meaning that it does not contain materials other than those described, except for the conventional impurities associated therewith. When the phrase "consisting of …" appears in a clause of the subject matter of the claims rather than immediately after the subject matter, it defines only the elements described in the clause; other elements are not excluded from the claims as a whole.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. "optional" or "any" means that the subsequently described event or events may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification and claims, is intended to modify a quantity, such that the invention is not limited to the specific quantity, but includes portions that are literally received for modification without substantial change in the basic function to which the invention is related. Accordingly, the use of "about" to modify a numerical value means that the invention is not limited to the precise value. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In the present description and claims, range limitations may be combined and/or interchanged, including all sub-ranges contained therein if not otherwise stated.

In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the stated number clearly indicates that the singular form is intended.

The present invention is illustrated by the following specific embodiments, but is not limited to the specific examples given below.

In a first aspect of the invention, an adhesive is provided, the adhesive being prepared from raw materials including a resin and a diluent.

Resin composition

The adhesive is coated on the alumite coating in a coating mode, because the resin is high molecular, if the content of the resin is too much, uneven coating is easily caused, the completeness of patterns after hot stamping and the smoothness of a coating film are affected, and the applicant finds that the hot stamping effect is good when the consumption of the resin is 15-30 wt%. In one embodiment, the resin of the present invention accounts for 15 to 30wt% of the binder; there may be mentioned, for example, 15 wt.%, 20 wt.%, 25 wt.%, 30 wt.%, preferably 20 wt.% 25 wt.%.

The applicant finds that when the acrylic resin and the polyester resin are used together as the resin of the adhesive, because the polar ester group structures of the acrylic resin and the polyester resin promote the compatibility of the acrylic resin and the polyester resin, the bonding force with the gloss oil and the alumite coating is also favorably improved, and preferably, the resin comprises at least two of acrylate resin, polyurethane resin, polyester resin and vinyl chloride-vinyl acetate resin; more preferably, the resin comprises acrylate resin and polyester resin, and the weight ratio is (1.1-2): 1; there may be mentioned, for example, 1.1: 1. 1.2: 1. 1.3: 1. 1.4: 1. 1.5: 1. 1.6: 1. 1.7: 1. 1.8: 1. 1.9: 1. 2.0: 1, preferably 1.2: 1. 1.3: 1. 1.4: 1. 1.5: 1. 1.6: 1. 1.67: 1. 1.7: 1. 1.8: 1, more preferably 1.5: 1. 1.6: 1. 1.67: 1. 1.7: 1. 1.8: 1.

the acrylic resin is a generic name of polymers of acrylic acid, methacrylic acid and derivatives thereof, and the acrylic resin is not specifically limited in the present invention, and may be homopolymers or copolymers of acrylic esters such as methyl methacrylate, butyl methacrylate, isobutyl methacrylate, ethyl acrylate and the like, or copolymers of acrylic esters and styrene, and is not specifically limited. Examples of the compounds include AR-446 (glass transition temperature of 46 to 52 ℃ C.), AR-508 (glass transition temperature of 62 ℃ C.), AR-568L (glass transition temperature of 109 ℃ C.), AR-1250SF (glass transition temperature of 60 to 80 ℃ C.), AR552 (glass transition temperature of 90 ℃ C.), AR-533 (glass transition temperature of 84 ℃ C.), and AR-554M2-6 (glass transition temperature of 73 ℃ C.) commercially available from Taiwan, Taiwan.

The polyester resin is a general term for a high molecular compound obtained by polycondensation of a diol or a diacid or a polyol and a polyacid. The polyester resins are classified into saturated polyester resins and unsaturated polyester resins. The polyester resin of the present invention is a saturated polyester resin, and there may be mentioned, for example, Mitsubishi Diacron series saturated polyester resins such as ER-502 (glass transition temperature: 57 ℃ C., weight average molecular weight: 26000), FC-916A (glass transition temperature: 62 ℃ C., weight average molecular weight: 7800), ER-535 (glass transition temperature: 60 ℃ C., weight average molecular weight: 8000), FC-1588 (glass transition temperature: 53 ℃ C., weight average molecular weight: 4700), FC-1565 (glass transition temperature: 62 ℃ C., weight average molecular weight: 72900), and FC-3057 (glass transition temperature: 7 ℃ C., weight average molecular weight: 144300).

The thermoprinting process needs to be carried out at 100-150 ℃, the applicant finds that when the glass transition temperature of the resin is controlled within a proper range, the movement of resin molecular chains is facilitated to form a continuous interface film for the adhesion of the alumite coating and the gloss oil during thermoprinting, and the applicant finds that when the glass transition temperature is too low, the film forming at a lower temperature is facilitated, but the movement of too high chain segments also influences the completeness and clarity of patterns, and when the glass transition temperature is too high, the movement of the resin molecular chains is not facilitated, so that the patterns are not thermoprinted on the gloss oil, and the uneven distribution of adhesion force is also caused. Further preferably, the glass transition temperature of the acrylic resin is 60 to 80 ℃, and 60 ℃, 65 ℃, 70 ℃, 75 ℃ and 80 ℃ can be enumerated. More preferably, the polyester resin of the present invention has a glass transition temperature of 60 to 70 ℃, which may be exemplified by 60 ℃, 62 ℃, 65 ℃, 68 ℃ and 70 ℃.

The applicant finds that the polyester resin comprises linear polyester resin or polyester resin containing benzene rings, so that the molecular weight difference is large under the condition of the same glass transition temperature, and the applicant finds that the movement of molecular chains in the hot stamping process is favorably controlled by controlling the molecular weight and the glass transition temperature of the polyester, so that the polyester resin and the acrylic resin are mutually wound to form a uniform and dense interfacial film together. In a preferred embodiment, the polyester resin of the present invention has a weight average molecular weight of 7000 to 10000, which may be 7000, 8000, 9000, and 10000.

The glass transition temperature (Tg) is the temperature at which the glass state changes to a highly elastic state. The weight average molecular weight is a statistical average molecular weight by mass, and is an average molecular weight obtained on a unit weight basis. The method for measuring the glass transition temperature and the weight average molecular weight is not particularly limited in the present invention, and is a method well known in the art.

In one embodiment, the raw materials for preparing the adhesive of the present invention further comprise a plasticizer.

Plasticizer

The applicant finds that when the adhesive is coated on the alumite coating, the diluent is quickly volatilized in the drying process, the high molecular weight resin is difficult to quickly move and is uniformly attached to the alumite coating, the perfection degree and the bonding strength of patterns in hot stamping are also influenced, and the movement of the resin can be promoted by adding the plasticizer with smaller molecular weight, such as chlorinated paraffin and the like. In one embodiment, the plasticizer of the present invention is selected from one or more of epoxidized soybean oil, white mineral oil, chlorinated paraffin, castor oil, dioctyl phthalate. Preferably, the weight ratio of the plasticizer to the resin is 1: (1.5-2.5), there may be mentioned, 1: 1.5, 1: 1.7, 1: 2. 1: 2.2, 1: 2.5, preferably 1: 1.7, 1: 2. 1: 2.2.

the chlorinated paraffin is an organic substance, namely a chlorinated derivative of paraffin hydrocarbon, has the advantages of low volatility, flame retardance, good electrical insulation, low price and the like, and can be used as a flame retardant and a polyvinyl chloride auxiliary plasticizer. As the chlorinated paraffin, chlorinated paraffin-70 (having a chlorine content of 70 wt%), chlorinated paraffin-52 (having a chlorine content of 52 wt%), and chlorinated paraffin-42 (having a chlorine content of 42 wt%) in the trade of Tianyuan chemical industry, Tokyo, can be mentioned, depending on the chlorine content.

The applicant finds that under the action of hot stamping temperature and pressure, patterns of the electrochemical aluminum coating can be deformed and blurred, and the applicant finds that when chlorinated paraffin, especially chlorinated paraffin with high chlorine content, is used and distributed among resins in the hot stamping process, the load-resistant capability of an interface film can be better improved, and the completeness and the clarity of the patterns are ensured. More preferably, the plasticizer of the present invention is a chlorinated paraffin; further preferably, the chlorine content of the chlorinated paraffin is 50-75 wt%; there may be mentioned, for example, 50 wt.%, 52 wt.%, 60 wt.%, 65 wt.%, 70 wt.%, 75 wt.%, preferably 65 wt.%, 70 wt.%, 75 wt.%.

The chlorine content is the mass percent of chlorine in the chlorinated paraffin and can be obtained by testing according to HG 3017-1988.

The applicant finds that when the chlorinated paraffin is added, the pattern deformation is reduced, and the chlorinated paraffin has lower molecular weight and molecular chain length, so that chain segment movement is more active in the hot stamping process, and the edge of the pattern is slightly blurred, and the slitting performance is influenced. Still more preferably, the resin of the present invention further comprises a vinyl chloride-vinyl acetate resin. In a preferred embodiment, the weight ratio of the vinyl chloride-vinyl acetate copolymer resin and the acrylic resin is 1: (2 to 3), there may be mentioned, 1: 2. 1: 2.2, 1: 2.5, 1: 2.7, 1: 3, preferably, 1: 2.2, 1: 2.5, 1: 2.7.

the vinyl chloride-vinyl acetate copolymer is a copolymer of vinyl chloride and vinyl acetate, and includes a binary vinyl chloride-vinyl acetate copolymer and a ternary vinyl chloride-vinyl acetate copolymer, wherein the ternary vinyl chloride-vinyl acetate copolymer is prepared by introducing a third monomer containing a carboxyl group or a hydroxyl group, and can be divided into a ternary hydroxyl vinyl chloride-vinyl acetate copolymer and a ternary carboxyl vinyl chloride-vinyl acetate copolymer according to the difference of the introduced functional groups, and examples of the vinyl chloride-vinyl acetate copolymer include, but are not limited to, binary vinyl chloride-vinyl acetate copolymers, such as Hanhua CP-430 (glass transition temperature of 63 ℃, polymerization degree of 430), CP-450 (glass transition temperature of 69 ℃, polymerization degree of 450), and CP-710 (glass transition temperature of 76 ℃, polymerization degree of 710); ternary hydroxychloroacetic acid resin such as TP-400A (glass transition temperature of 65 deg.C, polymerization degree of 400) and TP-500A (glass transition temperature of 67 deg.C, polymerization degree of 500) in Korea; the ternary carboxyl vinyl chloride-vinyl acetate copolymer resin is TP-400M (glass transition temperature of 76 deg.C, polymerization degree of 400) in Korea.

And the applicant finds that when the vinyl chloride-vinyl acetate copolymer is modified by carboxyl or hydroxyl, the slitting performance is more favorably improved, probably because the chlorinated hydrocarbon group in the chlorinated paraffin and vinyl chloride in the vinyl chloride-vinyl acetate copolymer have good compatibility and are favorably intertwined with each other, and the existence of the hydroxyl or the carboxyl, especially the existence of the carboxyl with high polarity is favorable for the adhesion of the chlorinated paraffin while the adsorption performance is improved, so that the excessive movement of small molecules of the chlorinated paraffin is reduced, and a pattern with clear edges is obtained. And the applicant finds that the dosage of the vinyl chloride-vinyl acetate copolymer needs to be controlled, and when the dosage of the vinyl chloride-vinyl acetate copolymer is too much, the cohesive force in the adhesive can be obviously increased, so that the resin is prevented from uniformly wetting gloss oil and a coating, and the hot stamping effect is influenced. In a more preferred embodiment, the vinyl chloride-vinyl acetate copolymer of the present invention is a ternary vinyl chloride-vinyl acetate copolymer or a binary vinyl chloride-vinyl acetate copolymer; preferred is a ternary vinyl chloride-vinyl acetate resin; more preferred is a ternary carboxy vinyl chloride-vinyl acetate resin. In a further preferred embodiment, the vinyl chloride-vinyl acetate copolymer of the present invention has a glass transition temperature of 60 to 80 ℃ and may be exemplified by 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃; more preferably, the polymerization degree of the vinyl chloride-vinyl acetate copolymer of the present invention is 350 to 600, and examples thereof include 350, 400, 430, 450, 500, 550 and 600, and preferably 350, 400, 430, 450 and 500.

The degree of polymerization is an index for measuring the molecular size of a polymer, is an average value of the number of repeating units contained in a polymer macromolecular chain, and can be tested according to JIS K6721.

Diluent

The diluent is not specifically limited in the present invention, and may be a diluent commonly used in the art, and there may be mentioned ketones such as acetone, methyl ethyl ketone; esters, such as ethyl acetate, n-propyl acetate, butyl acetate; alcohols, such as ethanol, methanol, isopropanol; in one embodiment, the diluent of the present invention is an ester; preferred are ethyl acetate and n-propyl acetate; in a preferred embodiment, the weight ratio of ethyl acetate to n-propyl acetate according to the invention is 1: (1-2).

In a second aspect, the present invention provides a method for preparing the adhesive, comprising the steps of: and mixing the preparation raw materials of the adhesive to obtain the adhesive.

The third aspect of the invention provides an application of the adhesive on the laser electrochemical aluminum paint.

Examples

The present invention will be specifically described below by way of examples. It should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the insubstantial modifications and adaptations of the present invention by those skilled in the art based on the above disclosure are still within the scope of the present invention.

A1: acrylic resin

The acrylic resin was purchased from Taiwan incorporated AR-508.

A2: acrylic resin

The acrylic resin was purchased from Taiwan, Inc. AR-1250 SF.

B1: polyester resin

The polyester resin was purchased from Mitsubishi FC-916A.

B2: polyester resin

The polyester resin was purchased from Mitsubishi ER-535.

B3: polyester resin

The polyester resin was purchased from Mitsubishi FC-3057, Japan.

C1: vinyl chloride-vinyl acetate copolymer

The vinyl chloride-vinyl acetate copolymer was purchased from TP-400M in Korea.

C2: vinyl chloride-vinyl acetate copolymer

The vinyl chloride-vinyl acetate copolymer was purchased from TP-500A of Korea.

C3: vinyl chloride-vinyl acetate copolymer

The vinyl chloride-vinyl acetate resin was purchased from CP-450 in Korea.

D1: chlorinated paraffin

The chlorinated paraffin is purchased from chlorinated paraffin-70 of the Tianyuan chemical industry of Totai city.

D2: chlorinated paraffin

The chlorinated paraffin is purchased from chlorinated paraffin-42 of the Tianyuan chemical industry of Totai city.

E1: diluent

The diluent is ethyl acetate.

E2: diluent

The diluent is n-propyl acetate.

TABLE 1

Examples 1 to 10 provide an adhesive, which is prepared from the raw materials in percentage by weight as shown in table 1.

Embodiments 1 to 10 also provide a method of preparing the adhesive as described above, including the steps of: and mixing the preparation raw materials of the adhesive to obtain the adhesive.

Evaluation of Performance

The adhesive provided by the embodiment is coated on a laser electrochemical aluminum coating and dried to obtain an electrochemical aluminum film, the electrochemical aluminum film is hot stamped in a hot stamping machine at 110 ℃, a gloss oil layer is arranged on the stamping surface of a material to be hot stamped, and the performance of a sample obtained after hot stamping is observed.

1. Adhesion force: after the 3M transparent adhesive tape was pressed on the surface of the sample containing the alumite coating, the adhesive tape was pulled apart in the direction perpendicular to the sample to completely separate the adhesive tape from the sample, and whether the sample was peeled off was observed, wherein no peeling was observed in level 1, holes were observed in level 2, holes were increased in level 3, and sheets were slightly peeled off, and sheets were increased in level 4, and the results are shown in Table 2.

2. Pattern integrity: and (3) observing the integrity of the pattern on the surface of the sample, and judging whether the color is changed or not or the color is dark, wherein the pattern is complete and is not changed, the color brightness level is O, otherwise, the color brightness level is marked as X, and the result is shown in the table 2.

3. Slitting property: and observing whether the pattern edge on the surface of the sample has a toothed edge or not and whether the edge is clear, and grading, wherein the 1 grade is that the toothed edge is not generated and the edge is clear, the 2 grade is that the toothed edge is slightly generated, the 3 grade is that the toothed edge is common, the 4 grade is that the toothed edge is more, and the 5 grade is that the toothed edge is obvious, and the result is shown in table 2.

Table 2 characterization test of properties

The test results in table 2 show that the adhesive provided by the invention can be used for bonding the laser electrochemical aluminum coating and the base material, and has good cohesiveness with gloss oil on the base material and a coating, and the pattern after hot stamping is complete and clear without phenomena such as light loss and the like.

The foregoing examples are merely illustrative and serve to explain some of the features of the method of the present invention. The appended claims are intended to claim as broad a scope as is contemplated, and the examples presented herein are merely illustrative of selected implementations in accordance with all possible combinations of examples. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples illustrating features of the invention. Also, where numerical ranges are used in the claims, subranges therein are included, and variations in these ranges are also to be construed as possible being covered by the appended claims.

Claims

1. The adhesive for the laser electrochemical aluminum coating is characterized in that raw materials for preparing the adhesive comprise resin and a diluent;

the resin is acrylate resin, polyester resin or vinyl chloride-vinyl acetate resin, and accounts for 15-30 wt% of the adhesive;

the weight ratio of the acrylate resin to the polyester resin is (1.1-2): 1; the glass transition temperature of the acrylate resin is 60-80 ℃; the glass transition temperature of the polyester resin is 60-70 ℃; the weight average molecular weight of the polyester resin is 7000-10000;

the weight ratio of the vinyl chloride-vinyl acetate copolymer resin to the acrylate resin is 1: (2-3);

the adhesive is characterized by also comprising a plasticizer which is chlorinated paraffin, wherein the weight ratio of the plasticizer to resin is 1: (1.5-2.5); the chlorine content of the chlorinated paraffin is 50-75 wt%.

2. The preparation method of the adhesive for the laser electrochemical aluminum paint according to claim 1, characterized by comprising the following steps: and mixing the preparation raw materials of the adhesive to obtain the adhesive.