阅读说明：本技术 一种金属罐紫外光固化外边缝涂料及制备方法 (Ultraviolet-curing outer seam coating for metal can and preparation method thereof ) 是由 赵炯 于 2021-07-20 设计创作，主要内容包括：本发明属于涂料技术领域,具体涉及一种金属罐紫外光固化外边缝涂料及其制备方法。本发明的金属罐紫外光固化外边缝涂料,以重量份计包括如下组分：双官能度脂肪族聚氨酯丙烯酸树脂30-40份,三官能度脂肪族聚氨酯丙烯酸树脂10-25份,丙烯酸异冰片酯20-25份,1,6-己二醇二丙烯酸酯20-30份,二氧化硅0.1-0.2份,碳化硅0.1-0.2份,光引发剂5-9份,助剂2.5-5份。本发明的金属罐紫外光固化外边缝补涂涂料形成的固化膜与油墨、光油与素铁具有优异的附着力,较好耐化学性能,较好的耐冲击性能。(The invention belongs to the technical field of coatings, and particularly relates to an ultraviolet-cured coating for an outer seam of a metal can and a preparation method thereof. The ultraviolet-curing outer seam coating for the metal can comprises the following components in parts by weight: 30-40 parts of bifunctional aliphatic polyurethane acrylic resin, 10-25 parts of trifunctional aliphatic polyurethane acrylic resin, 20-25 parts of isobornyl acrylate, 20-30 parts of 1, 6-hexanediol diacrylate, 0.1-0.2 part of silicon dioxide, 0.1-0.2 part of silicon carbide, 5-9 parts of photoinitiator and 2.5-5 parts of auxiliary agent. The curing film formed by the ultraviolet curing outside seam repair coating of the metal can has excellent adhesive force with printing ink, gloss oil and plain iron, and has better chemical resistance and impact resistance.)

1. The ultraviolet-curing exterior seam coating for the metal can is characterized by comprising the following components in parts by weight: 30-40 parts of bifunctional aliphatic polyurethane acrylic resin, 10-25 parts of trifunctional aliphatic polyurethane acrylic resin, 20-25 parts of isobornyl acrylate, 20-30 parts of 1, 6-hexanediol diacrylate, 0.1-0.2 part of silicon dioxide, 0.1-0.2 part of silicon carbide, 5-9 parts of photoinitiator and 2.5-5 parts of auxiliary agent.

2. The ultraviolet light-curable exterior seam coating for metal cans according to claim 1, wherein the silica has a particle size of 30-150 nm; the granularity of the silicon carbide is 30-150 nm.

3. The ultraviolet-curable paint for the outer edge seam of the metal can as claimed in claim 2, wherein the particle size of the silica is 40-60nm, and the particle size of the silica is 40-60 nm.

4. The UV-curable exterior seam coating for metal cans as claimed in claim 1, wherein the photoinitiator is a mixture of three photoinitiators, i.e., TPO, 907 and 1173.

5. The UV-curable exterior seam coating for metal cans as claimed in claim 4, wherein the weight ratio of the photoinitiator-TPO, the photoinitiator-907 and the photoinitiator-1173 is 1: (0.1-0.2): 0.2-0.5.

6. The ultraviolet-curable exterior seam coating for metal cans of claim 1, wherein the auxiliary agents comprise silane coupling agents, adhesion promoters and waxes.

7. The ultraviolet-curable exterior seam coating for metal cans as claimed in claim 6, wherein the weight ratio of the silane coupling agent, the adhesion promoter and the wax is 1-2: 1-2: 0.5-1.

8. The UV-curable overseal coating for metal cans of claim 6 wherein the wax is polyethylene wax.

9. A method for preparing the ultraviolet-curable outside seam coating for metal cans according to any one of claims 1 to 8, comprising the steps of:

mixing and stirring difunctional aliphatic polyurethane acrylic resin, trifunctional polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate, and stirring for 30-40 min to obtain a resin mixed solution;

adding silicon dioxide, silicon carbide, a photoinitiator and an auxiliary agent into the resin mixed solution, and continuously stirring until the mixture is uniformly mixed to prepare the ultraviolet curing outer seam coating of the metal can.

Technical Field

The invention belongs to the technical field of coatings, and particularly relates to an ultraviolet-cured coating for repairing and coating an outer seam of a metal can and a preparation method thereof.

Background

The metal packaging container has flexibility and variability, can be made into various shapes to meet the packaging requirements of different products, has the advantages of bright color, rich layers, good visual effect and the like by metal printing, can realize the unique shape and the exquisite printing effect of the product by exquisite shape design, not only improves the durability and the retainability of the commodity, but also meets the requirements of people on the art of the printed matter of the packaging container. At present, metal packaging becomes an important component of the Chinese packaging industry, the output value of the metal packaging accounts for about 10 percent of the total output value of the Chinese packaging industry, and the metal packaging is widely applied to the fields of food packaging, pharmaceutical packaging, daily necessities packaging, instrument and meter packaging, industrial product packaging and the like.

After the metal printing stock is coated and printed, in order to prevent the welding position from rusting in the process of manufacturing the tank, the welding position needs to be coated with edge seam coating so as to meet the shelf life requirement of a client. At present, the coating for repairing and coating the outer seam of the metal can is mainly prepared by the traditional thermosetting process, the production energy consumption is high, the time is relatively long, the occupied area is large, and a large amount of solvent volatilizes in the production process to pollute the environment. The ultraviolet light curing (UV) process has low energy consumption and high efficiency, does not generate volatile solvent, and is an excellent process with energy saving, high efficiency and environmental protection.

In addition, the coating for repairing the outer seam of the metal can needs to have certain glossiness and good leveling property; the product does not turn yellow or change color in shelf life; has sufficient friction resistance and corrosion resistance; has good flexibility, impact resistance and other properties.

Therefore, there is a need in the art to develop a UV-curable exterior seam coating with comprehensive performance.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides an ultraviolet-curing outer seam coating for a metal can and a preparation method thereof.

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

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight: 30-40 parts of bifunctional aliphatic polyurethane acrylic resin, 10-25 parts of trifunctional aliphatic polyurethane acrylic resin, 20-25 parts of isobornyl acrylate, 20-30 parts of 1, 6-hexanediol diacrylate, 0.1-0.2 part of silicon dioxide, 0.1-0.2 part of silicon carbide, 5-9 parts of photoinitiator and 2.5-5 parts of auxiliary agent.

Aiming at the characteristics of high processing resistance, high adhesive force requirement and the like of metal packaging, the invention adopts the aliphatic polyurethane acrylic resin which has excellent flexibility and chemical solvent resistance. In addition, the compounding of the bifunctional aliphatic polyurethane acrylic resin and the trifunctional aliphatic polyurethane acrylic resin can greatly improve the adhesive force of the coating, a printing surface and plain iron.

The isobornyl acrylate and the 1, 6-hexanediol diacrylate are mixed for use, so that the crosslinking degree and the curing efficiency of the coating can be improved, and the coating has more excellent processing resistance.

The silicon dioxide and the silicon carbide are added into the external seam coating, so that the defects of the coating can be reduced, and the corrosion resistance and the scratch resistance of the coating are obviously improved.

Preferably, the particle size of the silicon dioxide is 30-150 nm; more preferably, the silica has a particle size of 40 to 60 nm.

Preferably, the granularity of the silicon carbide is 30-150 nm; more preferably, the silica has a particle size of 40 to 60 nm.

Preferably, the photoinitiator is a mixture of three of photoinitiator-TPO, photoinitiator-907 and photoinitiator-1173. The absorption wavelength range of the photoinitiator TPO is 350-400nm, the absorption wavelength range of 907 is 260-320nm, the absorption wavelength range of 1173 is 240-260nm, the defect that the absorption wavelength of a single initiator is narrow can be overcome by compounding the three photoinitiators, all the wavelengths of 360-405 are covered, the utilization rate of ultraviolet light and the like of a production line is greatly improved, the curing efficiency is greatly improved, and the outer seam coating is not easy to yellow.

Preferably, the weight ratio of the photoinitiator-TPO, the photoinitiator-907 and the photoinitiator-1173 is 1: (0.1-0.2): 0.2-0.5.

Preferably, the auxiliary agent comprises a silane coupling agent, an adhesion promoter and wax.

Preferably, the weight ratio of the silane coupling agent to the adhesion promoter to the wax is 1-2: 1-2: 0.5 to 1; more preferably, the weight ratio of the silane coupling agent, the adhesion promoter and the wax is 1: 1: 0.5.

preferably, the wax is polyethylene wax.

The invention also provides a preparation method of the ultraviolet-curing outer seam coating for the metal can, which comprises the following steps:

mixing and stirring difunctional aliphatic polyurethane acrylic resin, trifunctional polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate, and stirring for 30-40 min to obtain a resin mixed solution;

adding silicon dioxide, silicon carbide, a photoinitiator and an auxiliary agent into the resin mixed solution, and continuously stirring until the mixture is uniformly mixed to prepare the ultraviolet curing outer seam coating of the metal can.

Preferably, the temperature is controlled to be 25-35 ℃ in the stirring process.

Compared with the prior art, the invention has the beneficial effects that:

the viscosity of the ultraviolet light cured outer seam coating is 20-30s (coating-4 cups, 125 ℃), and the coating has good adhesive force with plain iron, gloss oil and printing ink after forming a film, and the adhesive force reaches grade 1 through a Baige method.

According to the invention, the ultraviolet curing form is used for replacing the traditional thermosetting coating, and the selection of the active monomer and the photoinitiator can greatly improve the curing speed and reduce the process energy consumption, and the formed cured film has excellent wear resistance and flexibility, high chemical resistance and excellent impact resistance.

The photoinitiator and the oligomer adopted by the invention contain lower benzene series solvent. The cured product has no odor, is more environment-friendly, and meets the requirements of food packaging on sense.

Detailed Description

The technical solution of the present invention is further described below by means of specific examples.

Example 1:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

35 parts of bifunctional aliphatic polyurethane acrylic resin,

15 parts of trifunctional aliphatic polyurethane acrylic resin,

20 parts of isobornyl acrylate, 20 parts of,

20 parts of 1, 6-hexanediol diacrylate,

0.1 part of silicon dioxide, the particle size of the silicon dioxide is 100-150nm,

0.1 part of silicon carbide, the granularity of the silicon dioxide is 100-150nm,

1.0 part of photoinitiator-TPO,

9070.2 parts of a photoinitiator,

11730.5 parts of a photoinitiator,

2 parts of a silane coupling agent, namely,

2 parts of an adhesion promoter, namely 2 parts of,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, trifunctional aliphatic polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding silicon dioxide, silicon carbide, a photoinitiator, a silane coupling agent, an adhesion promoter and polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

Example 2:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

35 parts of bifunctional aliphatic polyurethane acrylic resin,

15 parts of trifunctional aliphatic polyurethane acrylic resin,

20 parts of isobornyl acrylate, 20 parts of,

20 parts of 1, 6-hexanediol diacrylate,

0.1 part of silicon dioxide, the particle size of the silicon dioxide is 40-60nm,

0.1 part of silicon carbide, the granularity of the silicon dioxide is 40-60nm,

1.0 part of photoinitiator-TPO,

9070.2 parts of a photoinitiator,

11730.5 parts of a photoinitiator,

2 parts of a silane coupling agent, namely,

2 parts of an adhesion promoter, namely 2 parts of,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, trifunctional aliphatic polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding silicon dioxide, silicon carbide, a photoinitiator, a silane coupling agent, an adhesion promoter and polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

Example 3:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

35 parts of bifunctional aliphatic polyurethane acrylic resin,

15 parts of trifunctional aliphatic polyurethane acrylic resin,

20 parts of isobornyl acrylate, 20 parts of,

20 parts of 1, 6-hexanediol diacrylate,

0.1 part of silicon dioxide, the particle size of the silicon dioxide is 40-60nm,

0.1 part of silicon carbide, the granularity of the silicon dioxide is 40-60nm,

1.0 part of photoinitiator-TPO,

9070.2 parts of a photoinitiator,

11730.5 parts of a photoinitiator,

1.0 part of silane coupling agent,

1.0 part of an adhesion promoter,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, trifunctional aliphatic polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding silicon dioxide, silicon carbide, a photoinitiator, a silane coupling agent, an adhesion promoter and polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

Comparative example 1:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

50 parts of bifunctional aliphatic polyurethane acrylic resin,

20 parts of isobornyl acrylate, 20 parts of,

20 parts of 1, 6-hexanediol diacrylate,

0.1 part of silicon dioxide, the particle size of the silicon dioxide is 40-60nm,

0.1 part of silicon carbide, the granularity of the silicon dioxide is 40-60nm,

1.0 part of photoinitiator-TPO,

9070.2 parts of a photoinitiator,

11730.5 parts of a photoinitiator,

1.0 part of silane coupling agent,

1.0 part of an adhesion promoter,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding silicon dioxide, silicon carbide, a photoinitiator, a silane coupling agent, an adhesion promoter and polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

Comparative example 2:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

35 parts of bifunctional aliphatic polyurethane acrylic resin,

15 parts of trifunctional aliphatic polyurethane acrylic resin,

40 parts of isobornyl acrylate, 40 parts of,

0.1 part of silicon dioxide, the particle size of the silicon dioxide is 40-60nm,

0.1 part of silicon carbide, the granularity of the silicon dioxide is 40-60nm,

1.0 part of photoinitiator-TPO,

9070.2 parts of a photoinitiator,

11730.5 parts of a photoinitiator,

1.0 part of silane coupling agent,

1.0 part of an adhesion promoter,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, trifunctional aliphatic polyurethane acrylic resin and isobornyl acrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding silicon dioxide, silicon carbide, a photoinitiator, a silane coupling agent, an adhesion promoter and polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

Comparative example 3:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

35 parts of bifunctional aliphatic polyurethane acrylic resin,

15 parts of trifunctional aliphatic polyurethane acrylic resin,

20 parts of isobornyl acrylate, 20 parts of,

20 parts of 1, 6-hexanediol diacrylate,

1.0 part of photoinitiator-TPO,

9070.2 parts of a photoinitiator,

11730.5 parts of a photoinitiator,

1.0 part of silane coupling agent,

1.0 part of an adhesion promoter,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, trifunctional aliphatic polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding the photoinitiator, the silane coupling agent, the adhesion promoter and the polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

Comparative example 4:

the ultraviolet curing outer seam coating for the metal can comprises the following components in parts by weight:

35 parts of bifunctional aliphatic polyurethane acrylic resin,

15 parts of trifunctional aliphatic polyurethane acrylic resin,

20 parts of isobornyl acrylate, 20 parts of,

20 parts of 1, 6-hexanediol diacrylate,

0.1 part of silicon dioxide, the particle size of the silicon dioxide is 40-60nm,

0.1 part of silicon carbide, the granularity of the silicon dioxide is 40-60nm,

2.0 parts of photoinitiator-TPO,

1.0 part of silane coupling agent,

1.0 part of an adhesion promoter,

0.5 part of polyethylene wax.

Correspondingly, the preparation method of the ultraviolet-curable outer seam coating for the metal can comprises the following steps:

adding bifunctional aliphatic polyurethane acrylic resin, trifunctional aliphatic polyurethane acrylic resin, isobornyl acrylate and 1, 6-hexanediol diacrylate into a reaction kettle according to the weight ratio, and stirring at 25-35 ℃ for 30-40 min to obtain a resin mixed solution;

and then adding silicon dioxide, silicon carbide, a photoinitiator, a silane coupling agent, an adhesion promoter and polyethylene wax into the resin mixed solution according to the proportion, and continuously stirring at 25-35 ℃ until the mixture is uniform to prepare the ultraviolet curing outer seam coating of the metal can.

The metallic printing coatings of examples 1-3 and comparative examples 1-4 were compared in terms of their properties, and the results are shown in the following table:

therefore, the ultraviolet light curing exterior seam coating can meet the requirements of construction and products, and a formed curing film has excellent adhesive force with printing ink, gloss oil and plain iron, better chemical resistance and better impact resistance.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims. While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.