Water-based gloss oil capable of gilding and suitable for UV code spraying and preparation method of water-based gloss oil

Abstract

The invention relates to water-based gloss oil capable of achieving gold stamping and suitable for UV code spraying and a preparation method of the water-based gloss oil. The water-based gloss oil is prepared from, by weight, 30-55 parts of water-based acrylic resin, 10-30 parts of polyurethane resin and other components. Wherein the water-based acrylic resin comprises 30-45 parts of water-based acrylic soft resin and 10-15 parts of water-based acrylic hard resin. Compared with the prior art, firstly, the acrylic resin, the polyurethane emulsion, the solvent and the auxiliaries are mixed in proportion and stirred at a high speed to obtain pre-dispersed gloss oil, the dispersed gloss oil is subjected to sanding treatment, it can be guaranteed that the resin and the auxiliaries are fully mixed, and it is guaranteed that a printed product is free of the conditions of trailing, foaming and the like. The raw materials of the product are all water-based materials, no toxic solvent is used, and harm to bodies of production workers and users is reduced. And the printing performance is stable, the glossiness is high, and the wear resistance and smoothness are good.

Description

Technical Field

[0001] The invention relates to the technical field of varnish, and in particular to a water-based varnish capable of hot stamping and suitable for UV coding and a preparation method thereof. Background Art

[0002] Varnish is a synthetic resin with the characteristics of natural resin. It usually refers to a transparent varnish on the surface. It is made of base materials and additives without any pigments. After film formation, it is shiny and glossy. It is commonly called varnish. In traditional printing industries such as tobacco, varnish is used as a transparent protective paint. Its hardness and wear resistance are better than those of color paint. It can protect printed products and improve their wear resistance and hardness. In addition, varnish itself can be subdivided into tactile varnish, matte varnish, high-gloss varnish, etc., to meet the needs of different products.

[0003] At present, UV inkjet printing is a necessary printing procedure in the tobacco printing industry, so it is necessary to keep pace with the times and design suitable varnishes to meet the needs of UV inkjet printing. In addition, hot stamping is also a common printing method in the tobacco printing industry. Many varnishes cannot meet the needs of hot stamping due to their surface tension. Summary of the invention

[0004] The purpose of the present invention is to provide a water-based varnish capable of hot stamping and suitable for UV inkjet coding and a preparation method thereof in order to overcome at least one of the defects of the above-mentioned prior art.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] In the present invention, the ratio of resin, solvent and auxiliary agent is limited, which can effectively control the viscosity and performance of varnish. In particular, if the ratio of auxiliary agent is too high, it is very likely that the surface performance of the produced varnish will be destroyed and cannot be used normally; at the same time, the present invention stipulates the feeding sequence, and the disordered feeding sequence will lead to the inability to fully mix the components, affecting the quality.

[0007] One of the purposes of the present invention is to provide a water-based varnish capable of hot stamping and suitable for UV inkjet coding, comprising the following components in parts by weight: 30-55 parts of a water-based acrylic resin, 10-30 parts of a polyurethane resin, and other components;

[0008] The water-based acrylic resin comprises 30-45 parts of a water-based acrylic soft resin and 10-15 parts of a water-based acrylic hard resin.

[0009] Furthermore, the following components are included by weight: 30-45 parts of water-based acrylic soft resin, 10-15 parts of water-based acrylic hard resin, 10-30 parts of polyurethane resin, 1-5 parts of organic solvent, 10-20 parts of water, 2.5-3 parts of surfactant, 1-10 parts of anti-wear agent, 1-3 parts of pH adjuster, 1-2 parts of defoaming agent, 1-2 parts of leveling agent, 0.5-1 parts of dispersant, and 0.5-1 parts of slip agent.

[0010] Furthermore, the preparation method of the water-based acrylic resin can refer to the existing patent CN104945556A.

[0011] Furthermore, the water-based acrylic resin has the advantages of excellent weather resistance, adjustable performance, no organic solvent release, and environmental protection. Water-based acrylic soft resin has good flexibility and film-forming properties, and can improve the adhesion of varnish. Water-based acrylic hard resin can improve its wear resistance and smoothness. Generally, soft and hard monomers are distinguished according to the glass transition temperature. Soft monomers have a low glass transition temperature, such as butyl acrylate and ethyl acrylate. Generally, the glass transition temperature is below 0°C. Hard monomers have a high glass transition temperature, such as methyl methacrylate. Polyurethane itself has a high solid content, excellent chemical corrosion resistance and good solvent resistance. Mixing in a certain proportion can combine the advantages of several resins, make up for their shortcomings, and obtain a resin binder with excellent performance.

[0012] Furthermore, the organic solvent is ethanol; the surfactant is disodium dodecylbenzene sulfonate; the anti-wear agent is wax emulsion; the pH regulator is ammonia water; the defoamer is emulsified silicone oil; the leveling agent includes isopropyl alcohol and / or propylene glycol; and the dispersant is octylphenol polyoxyethylene ether. Among them, the wax emulsion is mainly used to increase the wear resistance and scratch resistance of the varnish, the emulsified silicone oil can play a defoaming role, the isopropyl alcohol and propylene glycol can effectively improve the leveling of the varnish, and the surfactant can improve the surface tension of the varnish.

[0013] Furthermore, the concentration of the aqueous ammonia is 20-25wt%.

[0014] Furthermore, the leveling agent is a mixed liquid of isopropyl alcohol and propylene glycol in a mass ratio of (1-2):(1-3).

[0015] The second object of the present invention is to provide a method for preparing the water-based varnish capable of hot stamping and suitable for UV inkjet coding as described above, characterized in that it comprises the following steps:

[0016] Step 1: After the acrylic soft resin, organic solvent, water and pH adjuster are stirred for the first time, acrylic hard resin and polyurethane resin, anti-wear agent, defoaming agent and dispersant are added, and after the second stirring, the mixture is sand-milled to a fineness of less than 5 μm to obtain a varnish intermediate;

[0017] Step 2: After dispersing the varnish intermediate, add a leveling agent and a pH adjuster, adjust the pH to 8-9, and stir and disperse for the third time to obtain a water-based varnish that can be hot stamped and is suitable for UV inkjet coding.

[0018] Furthermore, in step 1, the first stirring speed is 500-800 rpm and the time is 20-30 min.

[0019] Furthermore, in step 1, the second stirring speed is 300-500 rpm and the time is 20-30 min.

[0020] Furthermore, in step 2, the third stirring speed is 300-500 rpm, and the stirring time is 20-30 min.

[0021] Furthermore, the temperature of the third stirring is 20-30°C.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The present invention first mixes acrylic resin, polyurethane emulsion, solvent and auxiliary agent in proportion, stirs at high speed to obtain pre-dispersed varnish, and sand-grinds the dispersed varnish to ensure that the resin and the auxiliary agent are fully mixed and that the printed product has no tailing, bubbling and the like. The raw materials of this product are all water-based materials, and no toxic solvents are used, which reduces the physical harm to production workers and users. The printing performance is stable, the gloss is high, and the wear resistance and smoothness are good.

[0024] (2) The present invention adjusts the surface tension of the varnish by using a large amount of soft acrylic resin and surfactant, which greatly meets the requirements of hot stamping and UV inkjet printing. In addition, no substances that conflict with UV ink are added to the varnish, and the surface smoothness also meets the requirements of UV inkjet printing. DETAILED DESCRIPTION

[0025] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0026] Example 1

[0027] This embodiment provides a water-based varnish that can be hot stamped and is suitable for UV inkjet coding, including the following components and their weight contents:

[0028]

[0029]

[0030] Other additives include 2 parts of wax emulsion anti-wear agent, 1.5 parts of pH regulator ammonia water, 1 part of emulsified silicone oil as defoamer, 1.5 parts of a mixed solution of isopropanol and propylene glycol as leveling agent, 0.5 parts of octylphenol polyoxyethylene ether as dispersant, and 0.5 parts of slip agent;

[0031] A method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet coding comprises the following steps:

[0032] (1) Varnish pretreatment:

[0033] Put acrylic soft resin, solvent and ammonia water into a high-speed mixer, and after they are completely dissolved, gradually add acrylic hard resin and polyurethane resin, wax emulsion, defoamer and dispersant into the high-speed dispersant, stir them evenly, and then sand grind them at a flow rate of 100Kg / hour to ensure that the fineness is less than 5μm. The preform of varnish is obtained.

[0034] (2) Varnish adjustment: After dispersing the varnish semi-finished product, add an auxiliary agent, and then add a pH adjuster to adjust the pH value to 8-9, stir and disperse, and then obtain the target product.

[0035] In step (1), the speed of high-speed stirring is 500-800 rpm. After adding the hard resin and polyurethane slurry, the speed of mixing and stirring is 300-500 rpm for 20-30 minutes.

[0036] In step (2), the conditions of the stirring and dispersing process are: a rotation speed of 300-500 rpm, a temperature of 20-30° C., and a stirring time of 30 min.

[0037] The varnish produced in this embodiment has good hot stamping and inkjet printing effects. The organic volatile content is about 3%. Taking coated paper as an example, the brightness of the water-based varnish can reach more than 72, and the wear resistance is 95% after more than 50 frictions under 4 pounds of pressure. It has good effects for hot stamping and inkjet printing.

[0038] Example 2

[0039] This embodiment provides a water-based varnish that can be hot stamped and is suitable for UV inkjet coding, including the following components and weight contents:

[0040]

[0041]

[0042] Other additives include 3 parts of wax emulsion anti-wear agent, 1.5 parts of pH regulator ammonia water, 1 part of emulsified silicone oil as defoamer, 1 part of a mixed solution of isopropanol and propylene glycol as leveling agent, 0.5 parts of octylphenol polyoxyethylene ether as dispersant, and 0.5 parts of slip agent;

[0043] A method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet coding comprises the following steps:

[0044] (1) Varnish pretreatment:

[0045] Put acrylic soft resin, solvent and ammonia water into a high-speed mixer, and after they are completely dissolved, gradually add acrylic hard resin and polyurethane resin, wax emulsion, defoamer and dispersant into the high-speed dispersant, stir them evenly, and then sand grind them at a flow rate of 100Kg / hour to ensure that the fineness is less than 5μm. The preform of varnish is obtained.

[0046] (2) Varnish adjustment: After dispersing the varnish semi-finished product, add an auxiliary agent, and then add a pH adjuster to adjust the pH value to 8-9, stir and disperse, and then obtain the target product.

[0047] In step (1), the speed of high-speed stirring is 500-800 rpm. After adding the hard resin and polyurethane slurry, the speed of mixing and stirring is 300-500 rpm for 20-30 minutes.

[0048] In step (2), the conditions of the stirring and dispersing process are: a rotation speed of 300-500 rpm, a temperature of 20-30° C., and a stirring time of 30 min.

[0049] The varnish produced in this embodiment has good hot stamping and coding effects. The organic volatile content is about 2%. Taking blue cardboard as an example, the brightness of the water-based varnish can reach more than 75. Under a pressure of 4 pounds, the wear resistance is more than 98% for 50 times, and the wear resistance is excellent. It is good for hot stamping and coding.

[0050] Table 1 Test results of volatile organic matter content in Example 1

[0051] Inspection items Inspection methods Testing standards Test data Test results Volatile organic matter content% HJ371-2018 ≤5 2 qualified

[0052] Table 2 Test results of glossiness, wear resistance, anti-adhesion, inkjet printing effect and hot stamping effect in Example 1

[0053]

[0054]

[0055] Comparative Example 1:

[0056] This comparative example is basically the same as Example 1, except that the water-based hard acrylic resin is omitted. The water-based varnish comparative example that can be bronzing and suitable for UV inkjet coding includes the following components and weight contents:

[0057]

[0058] The additives include 2 parts of wax emulsion anti-wear agent, 1.5 parts of pH regulator ammonia water, 1 part of emulsified silicone oil as defoamer, 1.5 parts of a mixed solution of isopropanol and propylene glycol as leveling agent, 0.5 parts of octylphenol polyoxyethylene ether as dispersant, and 0.5 parts of slip agent;

[0059] A method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet coding comprises the following steps:

[0060] (1) Varnish pretreatment:

[0061] Put acrylic soft resin, solvent and ammonia water into a high-speed mixer, and after they are completely dissolved, gradually add acrylic hard resin and polyurethane resin, wax emulsion, defoamer and dispersant into the high-speed dispersant, stir them evenly, and then sand grind them at a flow rate of 100Kg / hour to ensure that the fineness is less than 5μm. The preform of varnish is obtained.

[0062] (2) Varnish adjustment: After dispersing the varnish semi-finished product, add an auxiliary agent, and then add a pH adjuster to adjust the pH value to 8-9, stir and disperse, and then obtain the target product.

[0063] In step (1), the speed of high-speed stirring is 500-800 rpm. After adding the hard resin and polyurethane slurry, the speed of mixing and stirring is 300-500 rpm for 20-30 minutes.

[0064] In step (2), the conditions of the stirring and dispersing process are: a rotation speed of 300-500 rpm, a temperature of 20-30° C., and a stirring time of 30 minutes.

[0065] The varnish produced in this comparative example has good hot stamping and coding effects. The organic volatile content is about 2%; taking blue card paper as an example, the hot stamping and coding effects are good. The brightness of the water-based varnish can reach more than 75. Under 4 pounds of pressure, it is rubbed 50 times and is about 85%. The wear resistance is poor.

[0066] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A water-based varnish that can be hot stamped and is suitable for UV inkjet printing. It is characterized in that The composition comprises the following components by weight: 30-55 parts of water-based acrylic resin, 10-30 parts of polyurethane resin, and other components; The water-based acrylic resin comprises 30-45 parts of a water-based acrylic soft resin and 10-15 parts of a water-based acrylic hard resin.

2. The water-based varnish capable of hot stamping and suitable for UV inkjet coding according to claim 1, It is characterized in that The composition comprises the following components by weight: 30-45 parts of water-based acrylic soft resin, 10-15 parts of water-based acrylic hard resin, 10-30 parts of polyurethane resin, 1-5 parts of organic solvent, 10-20 parts of water, 2.5-3 parts of surfactant, 1-10 parts of anti-wear agent, 1-3 parts of pH regulator, 1-2 parts of defoaming agent, 1-2 parts of leveling agent, 0.5-1 parts of dispersant and 0.5-1 parts of slip agent.

3. The water-based varnish capable of hot stamping and suitable for UV inkjet coding according to claim 2, It is characterized in that The organic solvent is ethanol; The surfactant is disodium dodecylbenzene sulfonate; The anti-wear agent is a wax emulsion; The pH regulator is aqueous ammonia; The defoamer is emulsified silicone oil; The leveling agent includes isopropyl alcohol and / or propylene glycol; The dispersant is octylphenol polyoxyethylene ether.

4. The water-based varnish capable of hot stamping and suitable for UV inkjet coding according to claim 3, It is characterized in that The concentration of the aqueous ammonia is 20-25 wt %.

5. The water-based varnish capable of hot stamping and suitable for UV inkjet coding according to claim 3, It is characterized in that The leveling agent is a mixed liquid of isopropanol and propylene glycol in a mass ratio of (1-2):(1-3).

6. A method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet coding as claimed in any one of claims 1 to 5, It is characterized in that The steps include: Step 1: After the acrylic soft resin, organic solvent, water and pH adjuster are stirred for the first time, acrylic hard resin and polyurethane resin, anti-wear agent, defoaming agent and dispersant are added, and after the second stirring, the mixture is sand-milled to a fineness of less than 5 μm to obtain a varnish intermediate; Step 2: After dispersing the varnish intermediate, add a leveling agent and a pH adjuster, adjust the pH to 8-9, and stir and disperse for the third time to obtain a water-based varnish that can be hot stamped and is suitable for UV inkjet coding.

7. The method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet printing according to claim 6, It is characterized in that In step 1, the first stirring speed is 500-800 rpm and the time is 20-30 min.

8. The method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet coding according to claim 6, It is characterized in that In step 1, the second stirring speed is 300-500 rpm and the time is 20-30 min.

9. The method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet printing according to claim 6, It is characterized in that In step 2, the third stirring speed is 300-500 rpm, and the stirring time is 20-30 min.

10. The method for preparing a water-based varnish capable of hot stamping and suitable for UV inkjet coding according to claim 9, It is characterized in that The temperature of the third stirring is 20-30°C.

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