CN111234634A

CN111234634A - Pearlescent paint, spraying process thereof on surface of plastic product and application thereof

Info

Publication number: CN111234634A
Application number: CN202010226552.XA
Authority: CN
Inventors: 林伟生; 黄思佳
Original assignee: Dali Plastic Products Shenzhen Co Ltd
Current assignee: Dali Plastic Products Shenzhen Co Ltd
Priority date: 2020-03-26
Filing date: 2020-03-26
Publication date: 2020-06-05
Anticipated expiration: 2040-03-26
Also published as: CN111234634B

Abstract

The invention relates to the technical field of surface decoration of plastic products, in particular to pearlescent paint which is prepared by mixing and stirring the following components in parts by weight: 0 < pearlescent slurry: the self-drying treating agent is less than 1; the pearlescent paste is prepared from pearlescent powder and self-drying treatment agent according to the weight ratio of 1:1 in a weight ratio; the self-drying treatment agent is prepared from the following components in parts by weight: 5-10 parts of acrylic resin, 3-8 parts of modified epoxy resin, 20-30 parts of butyl acetate, 20-30 parts of methyl isobutyl ketone, 30-35 parts of ethyl formate, 0.5-1 part of flatting agent and 0.5-1 part of wetting agent; also provides a spraying process of the paint on the surface of a plastic product, thereby greatly reducing the production cost; also provides the application of the pearlescent paint in the surface decoration of plastic products, and the pearlescent paint is successfully applied to the decoration of the plastic products, so that the surfaces of the plastic products are flat and rich in luster, and have fine pearlescent effect.

Description

Pearlescent paint, spraying process thereof on surface of plastic product and application thereof

Technical Field

The invention relates to the technical field of plastic product surface decoration, in particular to a pearlescent paint, a spraying process of the pearlescent paint on the surface of a plastic product and application of the pearlescent paint.

Background

The cosmetic is a chemical industrial product or a fine chemical product which is applied, sprayed or the like to any part of the surface of a human body, such as skin, hair, lip and teeth, and the like, so as to achieve the purposes of cleaning, maintaining, beautifying, modifying and changing the appearance and keeping a good state. Such as pressed powder, foundation, eye shadow, blush, etc., are fine solid powdery cosmetics. For most of the cosmetics, regular polygonal powder boxes are adopted for containing. In order to realize light weight and reduce processing cost, most of the powder boxes are made of plastic materials. At present, in order to improve the appearance grade of the plastic powder box, one or more decorative layers are often sprayed on the surface of the plastic powder box, so that the plastic powder box has visual effects of metallic feeling, high brightness, frosted feeling and the like.

Compared with other paint vehicles, the pearlescent paint has unique and soft pearl gloss and can achieve incomparable effect with other paint vehicles. Due to the special surface structure, high refractive index and good transparency, the pearl gloss-like coating can also create the same effect as pearl gloss in a transparent medium. Generally the tint of a paint results from the selective absorption (or reflection) of light of a particular wavelength, whereas the tint of a pearlescent paint results from its refractive and interference effects on light. Therefore, the pearlescent paint can show the appearance effect of five-color and full-color enamel according to the types of the metal oxides added in the pearlescent paint.

In the prior art, a pearlescent paint is applied to the surface of a plastic product to improve the appearance grade of the plastic product. For example, the traditional spraying process for spraying decoration on the surface of the ABS plastic powder box is as follows: (1) cleaning the surface of the powder box to keep the surface of the powder box clean; (2) spraying traditional pearlescent paint on the surface of the powder box; (3) sending the powder box sprayed with the traditional pearlescent paint into an oven, and baking for 10-15min at 40-60 ℃; (4) spraying gloss oil on the dried traditional pearlescent paint layer on the surface of the powder box; (4) sending the powder box coated with gloss oil into an oven, and baking for 5-10min at 30-45 ℃; (5) and (4) carrying out photocuring drying treatment on the gloss oil on the surface of the powder box by using a UV (ultraviolet) curing machine to finally obtain the powder box with the pearlescent decorative layer. The formula of the traditional pearlescent paint is as follows: 30 wt% of self-drying acrylic resin added with pearl powder and 70 wt% of propylene glycol methyl ether; the addition amount of the pearl powder is determined by actual needs; and (3) mixing and stirring the self-drying acrylic resin mixed with the pearl powder and propylene glycol methyl ether uniformly to obtain the traditional pearl paint.

Through foretell traditional spraying process, can realize carrying out the effect of surface decoration to ABS plastic powder box. However, the above process has the following defects due to the influence of the properties of the traditional pearlescent paint: firstly, the traditional pearlescent paint cannot be dried automatically quickly after being sprayed on the surface of the powder box, and must be dried forcibly by virtue of an external environment, so that the drying operation in the step (3) is required, thereby increasing processing equipment, prolonging processing time, and causing the increase of equipment input cost and production cost of a production line; secondly, when the drying operation in the step (3) is carried out, the baking temperature and the baking time of the baking oven are influenced by the temperature and the humidity in the workshop every time, and if the baking temperature and the baking time are improperly controlled, the adhesive force of a paint layer is reduced, so that the paint layer is easy to fall off; thirdly, the spraying uniformity of the traditional pearlescent paint is not good enough, and a stepped flow-hanging layer is easily formed on the surface of the powder box, so that the application of the powder box in high-grade products is limited.

Disclosure of Invention

Aiming at the defects in the prior art, the first purpose of the invention is to provide the pearlescent paint for the surface of the plastic product, which does not need to be dried by the aid of the outside and has the advantages of high self-drying speed and good spraying sagging property.

The first purpose of the invention is realized by the following technical scheme:

the pearlescent paint for the surface of the plastic product is prepared by mixing and stirring the following raw materials in parts by weight: 0 < pearlescent slurry: the self-drying treating agent is less than 1; the pearlescent paste is prepared from pearlescent powder and self-drying treatment agent according to the weight ratio of 1:1 in a weight ratio; the self-drying treatment agent is prepared from the following raw materials in percentage by weight: 5-10% of acrylic resin, 3-8% of modified epoxy resin, 20-30% of butyl acetate, 20-30% of methyl isobutyl ketone, 30-35% of ethyl formate, 0.5-1% of flatting agent and 0.5-1% of wetting agent.

By adopting the technical scheme, in the self-drying treatment agent, the acrylic resin has the characteristics of high light and color retention, water and chemical resistance, quick drying and convenient construction; the modified epoxy resin has good physical and chemical properties, excellent adhesive property to the surface of plastic and small deformation shrinkage; acrylic resin and modified epoxy resin are used as main resin, so that the spraying sagging property of the paint can be improved; butyl acetate and methyl isobutyl ketone mainly play a role in dissolving and dispersing acrylic resin, modified epoxy resin and pearl powder, and ethyl formate has the characteristics of quick volatilization while playing a role in dissolving and dispersing. The self-drying treatment agent is matched with the pearl powder to obtain the pearl slurry, so that the pearl powder can be fully and uniformly dispersed in the self-drying treatment agent, and the phenomenon of local precipitation or layering caused by uneven dispersion of the pearl powder when the pearl paint is directly prepared is avoided. The pearlescent slurry is matched with the self-drying treatment agent to obtain the pearlescent paint, the ethyl formate in the self-drying treatment agent can accelerate the curing speed of the pearlescent paint, and the butyl acetate and the methyl isobutyl ketone are matched, so that on one hand, the dispersibility of the acrylic resin, the modified epoxy resin and the pearlescent powder is ensured, and the formed coating is more uniform and smooth; on the other hand, the curing speed is accelerated, the baking operation after the bead gloss paint is sprayed is omitted, and the production cost and the equipment investment cost are saved.

Preferably, the self-drying treatment agent is prepared from the following raw materials in percentage by weight: 6-8% of acrylic resin, 5-7% of modified epoxy resin, 23-27% of butyl acetate, 23-27% of methyl isobutyl ketone, 32-34% of ethyl formate, 0.5-1% of flatting agent and 0.5-1% of wetting agent.

Preferably, the self-drying treatment agent is prepared by the following steps:

1) mixing acrylic resin, modified epoxy resin, butyl acetate, methyl isobutyl ketone and ethyl formate, and uniformly stirring at a constant speed to obtain a mixed solution A;

2) and adding a leveling agent and a wetting agent into the mixed solution A, and uniformly mixing and stirring to obtain the self-drying treatment agent.

By adopting the technical scheme, the acrylic resin and the modified epoxy resin are fully dissolved by using butyl acetate, methyl isobutyl ketone and ethyl formate, and then the flatting agent and the wetting agent are added, so that the fully dissolved acrylic resin and the modified epoxy resin can be more uniformly dispersed in the solution, and the flatting property of the self-drying treatment agent is improved.

Preferably, in the step 2), the stirring speed is controlled to 3000-3500 r/min.

By adopting the technical scheme, the flatting agent and the wetting agent are fully dispersed in the mixed liquid A under the condition of high-speed stirring, and the flatting property and the self-drying property of the self-drying treating agent are further improved.

Preferably, the pearlescent paste is prepared by the following steps: and adding the pearl powder into the self-drying treatment agent, stirring uniformly, and circularly grinding until the fineness is not more than 8 mu m to obtain the pearl slurry.

By adopting the technical scheme, the pearl powder is dispersed in the self-drying treatment agent, and the grinding fineness is not more than 8 mu m, so that the pearl powder can be fully and uniformly dispersed in the self-drying treatment agent, the phenomenon of local precipitation or layering is avoided, and the finally obtained pearl paint is more fine and smooth after being sprayed.

The second purpose of the invention is to provide a spraying process of the pearlescent paint on the surface of the plastic product, which comprises the following spraying steps:

(1) carrying out electrostatic dust removal on the plastic product;

(2) spraying pearlescent paint on the surface of the plastic product;

(3) brushing the surface of the plastic product sprayed with the pearlescent paint along the same direction;

(4) spraying gloss oil on the surface of the brushed plastic product, and drying;

(5) and carrying out UV (ultraviolet) photocuring drying on the surface of the dried plastic product to finish spraying.

By adopting the technical scheme, the pearlescent paint disclosed by the invention is adopted for spraying, and the plastic product can be self-dried in the process of being transported to a gloss oil spraying line after being sprayed with the pearlescent paint, so that the baking step after spraying the pearlescent paint can be omitted, the traditional two-coating and two-baking process is simplified into two-coating and one-baking process, and the investment cost of equipment is saved; each batch of products of each production line are processed for at least 10-15min, and the processing cost is reduced; the problem of paint layer quality caused by improper adjustment of the baking conditions after paint spraying is avoided, so that the adhesive force of the paint layer is improved, the paint layer is firm, and the paint layer is not easy to fall off.

Preferably, in the step (2), the operation of the step (3) is performed for 0.5-1min after the pearlescent paint is sprayed on the surface of the plastic product.

By adopting the technical scheme, the time for conveying the product to be sprayed from the spraying line of the pearlescent paint to the spraying line of the gloss oil on the production line is 0.5-1min after the pearlescent paint is sprayed, namely the self-drying of the pearlescent paint can be completed in the conveying process, so that the time and the equipment investment are saved.

Preferably, in the step (5), the time for curing and drying by the UV light is 20-30 s.

Through adopting above-mentioned technical scheme, through UV photocuring drying, make the gloss oil layer on plastic products surface more level and more smooth.

The third purpose of the invention is to provide an application of the pearlescent paint in surface decoration of a plastic cosmetic packaging box, wherein the pearlescent paint is sprayed on the surface of the plastic cosmetic packaging box to obtain a decorative layer.

Preferably, the cosmetic plastic packaging box is made of ABS plastic materials.

By adopting the technical scheme, the ABS plastic has excellent impact resistance, good low-temperature performance and chemical resistance, and is widely applied to cosmetic plastic packaging boxes. But the appearance is poor, thereby limiting the application of the product in high-grade products. The invention improves the surface gloss and color of the ABS plastic packaging box by performing the pearl painting treatment on the surface of the ABS plastic packaging box, so that the ABS plastic packaging box is more suitable for high-grade products.

In conclusion, the invention has the following beneficial effects:

(1) the pearlescent paint can finish self-drying within 1min, has high self-drying speed and good spraying sagging property, and the formed paint film has flat and glossy surface;

(2) the pearlescent paint has excellent adhesive force on the surface of plastic, is not easy to fall off after a paint layer is formed, and has good decorative performance;

(3) the pearlescent paint provided by the invention is matched with the spraying process provided by the invention, and is applied to spraying decoration on the surface of a plastic powder box, so that the production cost of 101.7273 ten thousand yuan can be saved at least every year.

Detailed Description

The present invention will be further described with reference to the following specific examples.

The acrylic resin in the invention is selected from high molecular weight thermoplastic acrylic resin, the modified epoxy resin is selected from modified epoxy resin, the leveling agent is selected from byk uv3535, the wetting agent is selected from byk uv3505, and the pearl powder is a commercially available product.

Example 1

A pearlescent paint for the surface of a plastic product is prepared by mixing and stirring pearlescent slurry and a self-drying treatment agent according to the weight ratio of 1: 10. The composition of the self-drying treatment agent is shown in Table 1, and the processing operation is as follows:

1) adding acrylic resin, modified epoxy resin, butyl acetate, methyl isobutyl ketone and ethyl formate into a stirrer, and uniformly stirring at a constant speed of 800r/min to obtain a mixed solution A;

2) and (3) pumping the mixed solution A into a coating high-speed dispersion machine, then adding a flatting agent and a wetting agent, controlling the stirring speed to be 3000r/min, and uniformly mixing and stirring at a constant speed to obtain the self-drying treatment agent.

The pearlescent paste is prepared from pearlescent powder and self-drying treatment agent according to the weight ratio of 1:1, the concrete operation is as follows: adding the self-drying treatment agent into a stirrer, adding the pearlescent powder with equal weight into the self-drying treatment agent, starting the stirrer, stirring uniformly, and circularly grinding in a paint grinder until the fineness is not more than 8 mu m to obtain the pearlescent slurry.

Examples 2 to 6

The pearlescent paints of examples 2 to 6 were prepared in different amounts from those of the self-drying treatment agent of example 1, specifically shown in Table 1, and the rest was the same as that of example 1.

TABLE 1 composition of raw materials and amounts of self-drying treatment agent in examples 1-6

Examples 7 to 11

The pearlescent paints of examples 7 to 11 were prepared in the same manner as in example 1 except that the self-drying agent used in example 1 was used in different amounts as shown in Table 2.

TABLE 2 composition of raw materials and amounts of self-drying treatment agents in examples 7-11

Weight/kg	Example 7	Example 8	Example 9	Example 10	Example 11
						Acrylic resin	5	7	8	9	10
Modified epoxy resin	6	6	6	6	6
						Acetic acid butyl ester	27	27	27	26	25
Methyl isobutyl ketone	27	27	27	26	26
						Formic acid ethyl ester	33	31	30	31	31
Leveling agent	1	1	1	1	1
						Wetting agent	1	1	1	1	1

Example 12

A pearlescent paint for the surface of a plastic product is prepared by mixing and stirring pearlescent slurry and a self-drying treatment agent according to the weight ratio of 1: 10. The composition of the self-drying treatment agent is shown in Table 3, and the processing operation is specifically as follows:

2) and (3) pumping the mixed solution A into a coating high-speed dispersion machine, then adding a flatting agent and a wetting agent, controlling the stirring speed to be 3200r/min, and uniformly mixing and stirring at a constant speed to obtain the self-drying treating agent.

Example 13

2) and (3) pumping the mixed solution A into a coating high-speed dispersion machine, then adding a flatting agent and a wetting agent, controlling the stirring speed to be 3300r/min, and uniformly mixing and stirring at a constant speed to obtain the self-drying treatment agent.

Example 14

2) and (3) pumping the mixed solution A into a coating high-speed dispersion machine, then adding a flatting agent and a wetting agent, controlling the stirring speed to be 3400r/min, and uniformly mixing and stirring at a constant speed to obtain the self-drying treating agent.

Example 15

2) and (3) pumping the mixed solution A into a coating high-speed dispersion machine, then adding a flatting agent and a wetting agent, controlling the stirring speed to be 3500r/min, and uniformly mixing and stirring at a constant speed to obtain the self-drying treatment agent.

TABLE 3 composition of raw materials and amounts of self-drying treatment agents in examples 12-15

Weight/kg	Example 12	Example 13	Example 14	Example 15
					Acrylic resin	8	8	8	8
Modified epoxy resin	6	6	6	6
					Acetic acid butyl ester	30	20	27	27
Methyl isobutyl ketone	20	30	23	23
					Formic acid ethyl ester	34	34	34	34
Leveling agent	1	1	1	1
					Wetting agent	1	1	1	1

Examples 16 to 19

The weight ratio of the pearlescent slurry to the self-drying treatment agent in the pearlescent paints of examples 16-19 and 1 is different, and is shown in Table 4, and the rest is the same as that in example 1.

TABLE 4 weight ratio of pearlescent slurry to self-drying treatment agent in pearlescent paints of examples 16-19

	Example 16	Example 17	Example 18	Example 19
					Pearlescent slurry	1	1	1	1
Self-drying treatment agent	9	8	6	5

Comparative example 1

Conventional pearlescent paints in the background art.

Comparative example 2

The pearlescent paint of comparative example 2 is different from the pearlescent paint of example 16 in that the self-drying treatment agent does not contain the modified epoxy resin, and the rest of the composition and the content are the same.

Comparative example 3

The pearlescent paint of comparative example 3 is different from the pearlescent paint of example 16 in that the preparation step of the self-drying treatment agent is a one-step mixing method, and the rest of the operation, the composition and the content are the same.

Comparative example 4

The difference between the pearlescent paint of comparative example 4 and the pearlescent paint of example 16 is that in the preparation step of the self-drying treatment agent, the stirring speed of step (2) is 1000r/min, and the rest of the operations, compositions and contents are the same.

Application examples 1 to 15

The pearlescent paints of the embodiments 1 to 15 are respectively applied to the surface decoration of the cosmetic plastic packaging box of the application examples 1 to 15, the material of the cosmetic plastic packaging box is ABS plastic, and a pearlescent decorative layer is formed on the surface of the cosmetic plastic packaging box by the pearlescent paints, and the specific spraying process is as follows:

(1) cleaning the surface of the plastic packaging box, placing the surface on a production line table, and sending the surface into an electrostatic dust removal line for electrostatic dust removal;

(2) spraying pearlescent paint on the surface of the plastic packaging box subjected to electrostatic dust removal, wherein the spraying parameters are that the air pressure of a spray gun is set to be 0.45MPa, the spraying width parameter is 6cm, and the spraying distance is 10 +/-2 cm, and after the spraying is finished, the plastic packaging box is placed on the production line platform again;

(3) transporting the plastic packaging box from the spraying line to a brush line, and controlling the time of the transportation process to be 0.5 min; controlling a brush on a brush line to brush and rub the surface of the plastic packaging box sprayed with the pearlescent paint along the same direction, so that the pearlescent chips on the surface of the plastic packaging box incline to the same side, and the surface smoothness of the plastic packaging box is kept;

(4) spraying UV gloss oil on the surface of the brushed plastic packaging box, wherein the spraying parameters are consistent with those of the pearlescent paint, conveying the painted plastic packaging box to a baking line through a production line table for drying after the spraying is finished, controlling the temperature of the baking line to be 33 ℃, and baking for 5 min;

(5) and (4) sending the dried plastic packaging box into a UV curing machine for UV curing and drying, and treating for 20s by using 800mJ UV light to finish the whole spraying process.

Application example 16

The pearlescent paint of the embodiment 16 is applied to the surface decoration of the cosmetic plastic packaging box of the application example 16, the material of the cosmetic plastic packaging box is ABS plastic, so that a pearlescent decorative layer is formed on the surface of the cosmetic plastic packaging box, and the specific spraying process comprises the following steps:

(3) transporting the plastic packaging box from the spraying line to a brush line, and controlling the time of the transportation process to be 0.6 min; controlling a brush on a brush line to brush and rub the surface of the plastic packaging box sprayed with the pearlescent paint along the same direction, so that the pearlescent chips on the surface of the plastic packaging box incline to the same side, and the surface smoothness of the plastic packaging box is kept;

(5) and (4) conveying the dried plastic packaging box into a UV curing machine for UV curing and drying, and treating for 24s by using 800mJ UV light to finish the whole spraying process.

Application example 17

The pearlescent paint of the embodiment 17 is applied to the surface decoration of the cosmetic plastic packaging box of the application example 17, the material of the cosmetic plastic packaging box is ABS plastic, so that a pearlescent decorative layer is formed on the surface of the cosmetic plastic packaging box, and the specific spraying process comprises the following steps:

(3) transporting the plastic packaging box from the spraying line to a brush line, and controlling the time of the transportation process to be 0.7 min; controlling a brush on a brush line to brush and rub the surface of the plastic packaging box sprayed with the pearlescent paint along the same direction, so that the pearlescent chips on the surface of the plastic packaging box incline to the same side, and the surface smoothness of the plastic packaging box is kept;

(5) and (4) sending the dried plastic packaging box into a UV curing machine for UV curing and drying, and treating for 25s by using 800mJ UV light to finish the whole spraying process.

Application example 18

The pearlescent paint of the embodiment 18 is applied to the surface decoration of the cosmetic plastic packaging box of the application example 18, the material of the cosmetic plastic packaging box is ABS plastic, so that a pearlescent decorative layer is formed on the surface of the cosmetic plastic packaging box, and the specific spraying process comprises the following steps:

(3) transporting the plastic packaging box from the spraying line to a brush line, and controlling the time of the transportation process to be 0.9 min; controlling a brush on a brush line to brush and rub the surface of the plastic packaging box sprayed with the pearlescent paint along the same direction, so that the pearlescent chips on the surface of the plastic packaging box incline to the same side, and the surface smoothness of the plastic packaging box is kept;

(4) spraying UV gloss oil on the surface of the brushed plastic packaging box, wherein the spraying parameters are consistent with those of the pearlescent paint, conveying the painted plastic packaging box to a baking line through a production line table for drying after the spraying is finished, controlling the temperature of the baking line to be 32 ℃, and baking for 5 min;

(5) and (4) sending the dried plastic packaging box into a UV curing machine for UV curing and drying, and treating for 28s by using 800mJ UV light to finish the whole spraying process.

Application example 19

The pearlescent paint of the embodiment 19 is applied to the surface decoration of the cosmetic plastic packaging box of the application example 19, the material of the cosmetic plastic packaging box is ABS plastic, so that a pearlescent decorative layer is formed on the surface of the cosmetic plastic packaging box, and the specific spraying process comprises the following steps:

(3) transporting the plastic packaging box from the spraying line to a brush line, and controlling the transportation process for 1 min; controlling a brush on a brush line to brush and rub the surface of the plastic packaging box sprayed with the pearlescent paint along the same direction, so that the pearlescent chips on the surface of the plastic packaging box incline to the same side, and the surface smoothness of the plastic packaging box is kept;

(4) spraying UV gloss oil on the surface of the brushed plastic packaging box, wherein the spraying parameters are consistent with those of the pearlescent paint, conveying the painted plastic packaging box to a baking line through a production line table for drying after the spraying is finished, controlling the temperature of the baking line to be 35 ℃, and baking for 5 min;

(5) and (4) sending the dried plastic packaging box into a UV curing machine for UV curing and drying, and treating for 30s by using 800mJ UV light to finish the whole spraying process.

Application of comparative examples 1 to 4

According to the spraying process in application example 16, the pearlescent paints of comparative examples 1 to 4 are respectively sprayed on the surfaces of the cosmetic plastic packaging boxes of comparative examples 1 to 4 to form the pearlescent decorative layers.

Effect detection

Respectively extracting the plastic cosmetic packaging boxes after the spraying in the step (2) in the application examples 1-19 and the application comparative examples 1-4, extracting 3 packaging boxes in each example, and performing performance test on the paint layer on the surface of the packaging box by adopting the following detection method, wherein 3 detection data in each example are averaged, and the specific result is shown in table 5.

And (3) viscosity testing: firmly pressing the 3M 810 adhesive tape on the paint layer on the surface of the packaging box, and adhering and pulling the 3M 810 adhesive tape and the test surface in a direction of 45 degrees or 60 degrees for 5 times to observe whether the package box falls off or not;

adhesion force: the adhesive force of the paint layer is tested by adopting a test method of GB9286, the adhesive force is gradually reduced from 0-3 level, and the adhesive force does not reach the standard from 4-5 level;

film hardness: the pencil hardness of the paint layer was determined using GBT 6739-.

TABLE 5 test results of pearlescent paint layers on surfaces of packaging boxes in application examples 1-19 and application comparative examples 1-4

The detection results in Table 5 show that the self-drying speed of the pearlescent paint is high after the pearlescent paint is sprayed on the surface of an ABS plastic packaging box, the adhesion, viscosity and pencil hardness of the paint film reach good states within 1min, and the paint film is self-dried within 1 min. The traditional pearlescent paint (application comparative example 1) can be dried only by baking after being sprayed, so that the paint film can not be dried obviously by adopting the spraying process of the invention, the adhesive force of the paint film does not meet the product requirement, and the viscosity and the pencil hardness are poor. The detection result of the application comparative example 2 shows that the modified epoxy resin has larger positive influence on the performance of the whole pearlescent paint; the effect of the application comparative example 2 is slightly better than that of the application comparative example 1, which shows that the performance of the treating agent of the acrylic resin system is superior to that of the traditional pearlescent paint system on the basis of the pearlescent paint formula and the spraying process. The detection results of the application comparative example 3 and the application comparative example 4 show that the processing technology of the self-drying treatment agent has great influence on the performance of the pearlescent paint, and the performance of the pearlescent paint is greatly reduced no matter the one-step mixing is carried out or the stirring speed in the step (2) is reduced.

The cosmetic plastic packaging boxes after the whole spraying process operation in application example 19 and application comparative examples 1-4 are respectively extracted, 3 packaging boxes are extracted in each example, the performance test is carried out on the paint layer on the surface of the packaging box by adopting the following detection method, the average value of 3 detection data in each example is obtained, and the specific result is shown in table 6.

film hardness: the pencil hardness of the paint layer is measured by adopting GBT 6739-;

weather resistance: the test is carried out by adopting GB/T1865-;

solid content: measured by GB 1725-2007;

the appearance of the paint film is as follows: and (5) observing with naked eyes.

TABLE 6 test results of the surface paint layer of the packaging box in application example 19 and application comparative examples 1 to 4

The detection results in Table 6 show that when the pearlescent paint and the spraying process thereof are sprayed on the surface of an ABS plastic packaging box, the decorative layer has the advantages of smooth and flat surface, rich luster, excellent weather resistance, solid content, adhesive force and other properties, and the pearlescent paint is far superior to the traditional pearlescent paint (application comparative example 1). The result of the application comparative example 2 shows that the modified epoxy resin in the self-drying treatment agent disclosed by the invention has uniform and large influence on the coating effect of the pearlescent paint after film spraying and film forming and on various performances of a finished paint film. The results of the application comparative examples 3 and 4 show that the processing technology of the self-drying treatment agent has great influence on the performance of the pearlescent paint, and the performance of the pearlescent paint is greatly reduced no matter the one-step mixing is carried out or the stirring speed of the step (2) is reduced. The detection results of the application comparative examples 2-4 show that the performance of the pearlescent paint has a great influence on the performance of the surface coating of the plastic product.

By adopting the pearlescent paint and the spraying process thereof, in the application of the surface decoration of plastic product packaging boxes, each production line can at least omit an industrial production line drying oven, 4 ten thousand yuan is calculated according to each industrial production line drying oven, and 5 production lines are shared in a workshop, so that the equipment investment of 5 multiplied by 4-20 ten thousand yuan is at least saved. Each batch of production on each production line can save at least 10min, and the power of the pipeline conveying device is calculated according to 100kW, so that the pipeline conveying device can save at least 10/60 × 100-16.66 kW × h of electric quantity; the power of an industrial production line oven is calculated according to 100kW, so that at least 10/60 multiplied by 100-16.66 kW h of electric quantity is saved; the electricity charge is calculated as 0.73 yuan/(kW × h) for the industrial flat time period, and 10min per production line can save at least (16.66+16.66) × 0.73 ═ 24.3236 yuan; the 5 production lines save 5 x 24.3236-121.618 yuan. The workshop is calculated according to 20 batches of production every day, so that 121.618 multiplied by 20 yuan is saved every day, and 336 multiplied by 2432.36 yuan is saved by at least 336 yuan by 817272.96 yuan by 336 working days every year. Therefore, the total investment of one year can save at least 20+ 81.7273-101.7273 ten thousand yuan.

The above-mentioned embodiments are only illustrative and not restrictive, and those skilled in the art can make modifications to the embodiments without inventive contribution as required after reading the present specification, but all of them are protected by patent laws within the scope of the claims of the present invention.

Claims

1. The pearlescent paint for the surface of the plastic product is characterized by being prepared by mixing and stirring the following raw materials in parts by weight: 0 < pearlescent slurry: the self-drying treating agent is less than 1; the pearlescent paste is prepared from pearlescent powder and self-drying treatment agent according to the weight ratio of 1:1 in a weight ratio; the self-drying treatment agent is prepared from the following raw materials in percentage by weight: 5-10% of acrylic resin, 3-8% of modified epoxy resin, 20-30% of butyl acetate, 20-30% of methyl isobutyl ketone, 30-35% of ethyl formate, 0.5-1% of flatting agent and 0.5-1% of wetting agent.

2. The pearlescent paint for plastic product surface according to claim 1, characterized in that: the self-drying treatment agent is prepared from the following raw materials in percentage by weight: 6-8% of acrylic resin, 5-7% of modified epoxy resin, 23-27% of butyl acetate, 23-27% of methyl isobutyl ketone, 32-34% of ethyl formate, 0.5-1% of flatting agent and 0.5-1% of wetting agent.

3. The pearlescent paint for the surface of plastic products as recited in claim 1, wherein the self-drying treatment agent is prepared by the following steps:

4. The pearlescent paint for plastic product surface according to claim 3, characterized in that: in the step 2), the stirring speed is controlled to be 3000-.

5. The pearlescent paint for the surface of plastic products according to claim 1, wherein the pearlescent paste is prepared by the following steps: and adding the pearl powder into the self-drying treatment agent, stirring uniformly, and circularly grinding until the fineness is not more than 8 mu m to obtain the pearl slurry.

6. A process for spraying a pearlescent paint on the surface of a plastic product according to any one of claims 1-5, which comprises the following spraying steps:

(1) carrying out electrostatic dust removal on the plastic product;

(2) spraying pearlescent paint on the surface of the plastic product;

7. The spraying process of the pearlescent paint on the surface of the plastic product according to claim 6, which is characterized in that: in the step (2), after the surface of the plastic product is sprayed with the pearlescent paint, the operation of the step (3) is carried out for 0.5-1 min.

8. The spraying process of the pearlescent paint on the surface of the plastic product according to claim 6, which is characterized in that: in the step (5), the time for curing and drying by the UV light is 20-30 s.

9. Use of a pearlescent paint according to any one of claims 1-5 in surface decoration of plastic cosmetic packaging boxes, characterized in that: and spraying the pearlescent paint on the surface of a plastic cosmetic packaging box to obtain the decorative layer.

10. Use of a pearlescent paint according to claim 9 in the surface decoration of cosmetic plastic packaging boxes, characterized in that: the cosmetic plastic packaging box is made of ABS plastic.