A printing ink for use in conjunction with a glazing agent

Abstract

The present application discloses a kind of printing ink used with gloss agent, the printing ink is used with gloss agent, the printing ink includes: pigment, polyhydroxy monomethyl acrylate, dimethyl dimethoxysilane, boric acid, bisphenol A type epoxy resin, polyether dihydric alcohol, dispersing wetting agent, antioxidant and oily solvent;The gloss agent includes;Water-based polyurethane, water-based isobutyl acrylate, photoinitiator, polyether amine.The present application can solve the problem that UV gloss oil and ink are not compatible, by pressing during glossing gloss oil and after glossing pressure roller, the polyether amine contained in UV curing gloss agent is contacted with the bisphenol A type epoxy resin and polyether dihydric alcohol contained in printing ink, to form internal polymerization between gloss oil and printing ink components, and improve the affinity effect between ink and gloss agent.

Description

Technical Field

[0001] This invention relates to the field of printing, and more particularly to a printing ink used in conjunction with a varnishing agent. Background Technology

[0002] Offset printing is an important branch of the printing industry, primarily focusing on flat printing. With economic development and technological advancements, the offset printing industry has experienced further growth.

[0003] With the development of the domestic economy and the improvement of people's living standards, a surge in consumer demand and the increasing need for advertising have led to a year-on-year increase in the demand for print printing. Currently, commercial printing is the main driver of print printing demand in the domestic market. At the same time, printing demand from other sectors such as packaging and magazines is also increasing annually.

[0004] However, offset printing usually struggles to create offset products with a distinct embossed texture. This is determined by the principle of offset printing as a transfer method. Unlike gravure printing, which uses a printing plate to create indentations on the printed material, offset printing relies solely on ink thickness to convey embossed texture. To ensure the ink's quick-drying properties and excellent adhesion, the ink layer cannot be too thick.

[0005] On the other hand, varnishing is often required after printing. Varnishes and inks are not always produced by the same manufacturer, and even when they are from the same manufacturer, their production is based on individual product experiments rather than a holistic approach. Therefore, UV-cured varnishes and printing inks often have incompatibility, and peeling can easily occur between the varnish layer and the ink layer if the printed product is bent or exposed to sunlight. Summary of the Invention

[0006] In view of this situation, the present invention aims to provide a printing ink that can increase printing thickness and has better affinity between the varnish layer and the ink layer.

[0007] To address the aforementioned problems, this invention, on the one hand, increases ink viscosity and screen size by adjusting the ink formulation, thereby increasing ink adhesion and improving the thickness of the cured ink. On the other hand, it adjusts the varnish formulation so that the two can undergo a polymerization reaction before UV curing, increasing their affinity.

[0008] This increases the embossed feel of the printed surface, allowing for the creation of textured products through offset printing without pressing the printed product, while also ensuring the affinity between the varnish layer and the ink layer.

[0009] Specifically, the present invention provides a printing ink for use in conjunction with a varnishing agent, characterized in that the printing ink is used in conjunction with the varnishing agent.

[0010] The printing ink comprises: pigments, polyhydroxy monomethacrylate, dimethyl dimethoxysilane, boric acid, bisphenol A epoxy resin, polyether diol, dispersing and wetting agents, antioxidants, and oily solvents;

[0011] The varnishing agent includes: waterborne polyurethane, waterborne isobutyl acrylate, photoinitiator, and polyetheramine.

[0012] In a preferred embodiment, the printing ink comprises 10-25 parts pigment, 15-18 parts polyhydroxy monomethacrylate, 14-16 parts dimethyldimethoxysilane, 1 part boric acid, 5-12 parts bisphenol A epoxy resin, 3-6 parts polyether diol, 0.5 parts dispersant and wetting agent, 0.5 parts antioxidant, and 20-25 parts oil solvent.

[0013] In another preferred embodiment, the proportions of the components in the varnish are: 8-10 parts of waterborne polyurethane, 30-35 parts of waterborne isobutyl acrylate, 3 parts of photoinitiator, and 5-10 parts of polyetheramine.

[0014] In another preferred embodiment, the polishing agent further includes 1.5-2 parts of emulsifier, 0.5-1 part of leveling agent, 0.5-1 part of plasticizer, and 0.5-1 part of antioxidant.

[0015] In another preferred embodiment, the varnish does not contain epoxy resin and the printing ink does not contain polyetheramine.

[0016] In another preferred embodiment, the varnish further includes an ultraviolet absorber.

[0017] In another preferred embodiment, the polyether diol can be polyoxypropylene diol or other polyether diols.

[0018] In another preferred embodiment, the ultraviolet absorber may be a mixture of benzotriazoles or other ultraviolet absorbers.

[0019] In another preferred embodiment, the antioxidant may be diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate or other light stabilizers.

[0020] In another preferred embodiment, the light stabilizer may be 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl) or other light stabilizers.

[0021] In another preferred embodiment, the pigment can be a yellow pigment such as diazo yellow or Hansa yellow, bright carmine, lake red C, phthalocyanine blue, phthalocyanine green, alkaline blue, or carbon black.

[0022] Preferably, the varnish also includes a catalyst (the catalyst is used to catalytically harden the two-component adhesive components contained in the printing ink and the varnish respectively), and the catalyst may be an organobismuth catalyst or an organotin catalyst.

[0023] The first component of the two-component adhesive mentioned above includes: bisphenol A type epoxy resin E-51, polyether diol N210, ultraviolet absorber, antioxidant, and light stabilizer; the other component is polyamide or polyether amine.

[0024] Technical effect

[0025] This invention increases ink viscosity and adhesion by adjusting the ink formula, thereby improving the thickness of the cured ink. On the other hand, it enhances the surface hardness of the ink by spraying a coating that interacts with the ink onto the surface. This results in a more pronounced textured surface in the ink-covered areas compared to the uninked areas, enabling the creation of textured products through offset printing without the need for pressing the printed product.

[0026] This invention solves the problem of incompatibility between UV varnish and ink. By pressing with pressure rollers during and after varnishing, the polyetheramine contained in the UV curing varnish comes into contact with the bisphenol A epoxy resin and polyether diol contained in the printing ink, forming internal polymerization between the components of the varnish and the printing ink, thus improving the affinity between the ink and the varnish. On the other hand, it also solves the problem of surface hardness after the printing ink thickens due to the use of an 80C screen. Thus, the printing ink of this invention, combined with the corresponding varnish, can achieve the printing of patterns with a certain embossed feel, that is, to achieve the effect of gravure printing using offset printing. Attached Figure Description

[0027] Figure 1 This is a schematic flowchart of a method for preparing printing ink in conjunction with a varnishing agent according to the present invention.

[0028] Figure 2 The orange printing ink obtained by scaling up the proportions in Example 1;

[0029] Figure 3 To obtain black printing ink by proportionally scaling up the process of replacing blue pigment with black pigment. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0031] The present invention provides a printing ink for use in conjunction with a varnishing agent.

[0032] The printing ink includes: pigments, polyhydroxy monomethacrylate, dimethyl dimethoxysilane, boric acid, bisphenol A epoxy resin, polyether diol, dispersant and wetting agent, antioxidant, and oil-based solvent;

[0033] The varnishing agent includes: waterborne polyurethane, waterborne isobutyl acrylate, photoinitiator, and polyetheramine.

[0034] When using printing inks, a 70-90C screen is used, preferably an 80C screen.

[0035] The printing ink contains 10-25 parts pigment, 15-18 parts polyhydroxy monomethacrylate, 14-16 parts dimethyldimethoxysilane, 1 part boric acid, 5-12 parts bisphenol A epoxy resin, 3-6 parts polyether diol, about 0.5 parts dispersing and wetting agent, about 0.5 parts antioxidant, and 20-25 parts oil solvent.

[0036] The proportions of each component in the varnish are as follows: 8-10 parts waterborne polyurethane, 30-35 parts waterborne isobutyl acrylate, 3 parts photoinitiator, and 5-10 parts polyetheramine.

[0037] Preferably, the polishing agent may also include 1.5-2 parts of emulsifier, 0.5-1 part of leveling agent, 0.5-1 part of plasticizer, and 0.5-1 part of antioxidant.

[0038] Example 1

[0039] In this embodiment, the printing ink includes: 16g of pigment, 16g of polyhydroxy monomethacrylate, 15g of dimethyldimethoxysilane, 1g of boric acid, 6g of bisphenol A epoxy resin, 3g of polyether diol, 0.5g of dispersant and wetting agent, 0.5g of antioxidant, and 22g of oil solvent.

[0040] In this embodiment, the pigment used is a mixture of benzidine yellow and BASF L4763 organic red, with a ratio between 1:3 and 3:1. The polyhydroxy monomethacrylate used is 1,4-butanediol methacrylate, and the oil-based solvent is a mixture of 50% isopropanol and 50% toluene. Using this mixed solvent facilitates further compatibility between the varnish and ink components after offset printing, because isopropanol has good compatibility with water-based substances.

[0041] The varnishing agent comprises: 9g of waterborne polyurethane, 32g of waterborne isobutyl acrylate, 3g of photoinitiator, and 8g of polyetheramine. The waterborne polyurethane can be RL-8303A or Qingdao Ruikes' waterborne polyurethane emulsion. When using the waterborne isobutyl acrylate, it must be determined whether it contains the stabilizer MEHQ. If it does not contain a stabilizer, 1% stabilizer should be added after opening. The mass in the examples refers to the total mass including the stabilizer.

[0042] In the preparation of printing ink, powdered materials, such as boric acid and pigment powder, are ground and sieved under anaerobic conditions for pretreatment. Then, accurately weigh 16g of pigment, 16g of polyhydroxy monomethacrylate, 15g of dimethyldimethoxysilane, 1g of boric acid, 6g of bisphenol A epoxy resin, 3g of polyether diol, 0.5g of dispersing and wetting agent, 0.5g of antioxidant, and 22g of oil-based solvent. Next, add the polyhydroxy monomethacrylate, dimethyldimethoxysilane, bisphenol A epoxy resin, polyether diol, dispersing and wetting agent (optional), and antioxidant (optional) to the oil-based solvent and stir until homogeneous, maintaining the stirring state. Add the sieved boric acid, benzidine yellow, and red pigment, and continue stirring. Under sealed conditions and with inert gas introduced, heat to 60-80 degrees Celsius, continue stirring for 0.5-1 hour, cool to room temperature, and remove to obtain printing ink sample 1.

[0043] In the preparation of the varnish, 9g of waterborne polyurethane, 32g of waterborne isobutyl acrylate, 3g of photoinitiator, and 8g of polyetheramine were accurately weighed. The waterborne polyurethane, photoinitiator, and polyetheramine were added to the waterborne isobutyl acrylate, stirred evenly, sealed and stored to obtain varnish sample 2.

[0044] Those skilled in the art should understand that the mass fraction of the pigment can be appropriately adjusted within a wider range, depending on the pigment selected. Pigments can be organic or inorganic, and can be natural or synthetic pigments, such as malachite green, cinnabar, red clay, wollastonite, barite powder, talc powder, mica powder, heavy calcium carbonate, titanium dioxide, iron blue, etc. Existing finished pigments such as BASF Pelite pigments or Clariant pigments can also be used.

[0045] like Figure 2 The image shows a production ink prepared by scaling up the components proportionally according to this embodiment, with yellow and red pigments mixed in a 6:4 ratio.

[0046] Example 2

[0047] This embodiment provides a printing ink used in conjunction with a varnishing agent.

[0048] In this embodiment, the printing ink includes: 12g pigment, 18g polyhydroxy monomethacrylate, 15g dimethyl dimethoxysilane, 1g boric acid, 7g bisphenol A epoxy resin, 3g polyether diol, 0.5g dispersant and wetting agent, 0.5g antioxidant, and 25g oil solvent.

[0049] In this embodiment, the pigment is a mixture of phthalocyanine blue (or other blue pigment) and carbon black (or other pigments) to form a blue-black color, with the phthalocyanine blue comprising 10%-90% by mass. Compared to using only dark blue pigment, the pigment obtained by combining blue and black in this invention allows for better control of color gradation and exhibits better high-temperature resistance and lightfastness compared to using only organic pigments.

[0050] The polyhydroxy monomethacrylate used is 1,4-butanediol methacrylate, and the oil-based solvent is a mixture of 50% isopropanol and 50% toluene. Using this mixed solvent facilitates further compatibility between the varnish and ink components after offset printing.

[0051] The varnishing agent comprises: 12g of waterborne polyurethane, 30g of waterborne isobutyl acrylate, 3g of photoinitiator, 10g of polyetheramine, and 0.5g of organic bismuth catalyst (e.g., bismuth neodecanoate). The waterborne polyurethane can be RL-8303A or Qingdao Ruikes' waterborne polyurethane emulsion. When using the waterborne isobutyl acrylate, it is necessary to determine whether it contains the stabilizer MEHQ. If it does not contain a stabilizer, 1% stabilizer should be added after opening. The mass in the examples refers to the total mass including the stabilizer.

[0052] In the preparation of printing ink, the powdered materials are thoroughly ground, stirred, and sieved beforehand. Then, accurately weigh 12g of pigment, 18g of polyhydroxy monomethacrylate, 15g of dimethyldimethoxysilane, 1g of boric acid, 7g of bisphenol A epoxy resin, 3g of polyether diol, 0.5g of dispersing and wetting agent, 0.5g of antioxidant, and 25g of oil-based solvent. Next, add the polyhydroxy monomethacrylate, dimethyldimethoxysilane, boric acid, bisphenol A epoxy resin, polyether diol, dispersing and wetting agent, and antioxidant to the oil-based solvent and stir until homogeneous, maintaining the stirring state. Add the sieved boric acid and pigment mixture, and continue stirring. Under sealed conditions and with inert gas introduced, heat to 60-80 degrees Celsius, continue stirring for 0.5-1 hour, cool to room temperature, and remove to obtain printing ink sample 2. The dispersing and wetting agent used is modified polyester, a commercially available product.

[0053] During the preparation of the varnish, accurately weigh 9g of waterborne polyurethane, 32g of waterborne isobutyl acrylate, 3g of photoinitiator, 10g of polyetheramine, and 0.5g of organic bismuth catalyst. Add the waterborne polyurethane, photoinitiator, and polyetheramine to the waterborne isobutyl acrylate, stir evenly, and seal for storage.

[0054] Figure 3 To achieve the formulation of this embodiment, the pigment used is carbon black to obtain the production ink.

[0055] Comparative Example

[0056] In this comparative example, the printing ink includes: 12g pigment, 25g polyhydroxy monomethacrylate, 18g dimethyldimethoxysilane, 1g boric acid, 0.5g dispersant and wetting agent, 0.5g antioxidant, and 25g oil solvent.

[0057] Compared with Example 1, this comparative example does not add bisphenol A type epoxy resin and polyether diol, but replaces the weight parts of the two with polyhydroxy monomethacrylate and dimethyl dimethoxysilane.

[0058] In this comparative example, the pigments and other components used were the same raw materials from the same manufacturer as in Example 1.

[0059] The pigment is a mixture of phthalocyanine blue (or other blue pigments) and carbon black (or other pigments) to form a blue-black color, with the phthalocyanine blue accounting for 20%-80% of the total mass.

[0060] The polyhydroxy monomethacrylate used is 1,4-butanediol methacrylate, and the oil-based solvent is a mixture of 50% isopropanol and 50% toluene. Using this mixed solvent facilitates further compatibility between the varnish and ink components after offset printing.

[0061] The varnish comprises: 14.5g of waterborne polyurethane, 37.5g of waterborne isobutyl acrylate, and 3g of photoinitiator. In this comparative example, polyetheramine was not added to the varnish; instead, it was replaced with equal proportions of waterborne polyurethane and waterborne isobutyl acrylate.

[0062] In the preparation of printing ink, the powder material is thoroughly ground, stirred, and sieved beforehand. Then, each component is accurately weighed. Next, polyhydroxy monomethacrylate, dimethyldimethoxysilane, boric acid, dispersant, wetting agent, and antioxidant are added to an oil-based solvent and stirred until homogeneous, maintaining the stirring state. The sieved boric acid and pigment mixture is then added, and stirring continues. Under sealed conditions and with inert gas introduced, the temperature is raised to 60-80 degrees Celsius, and stirring continues for 0.5-1 hour. After cooling to room temperature, the ink sample 1 is obtained.

[0063] During the preparation of the varnish, accurately weigh 9g of waterborne polyurethane, 32g of waterborne isobutyl acrylate, and 3g of photoinitiator. Add the waterborne polyurethane, photoinitiator, and polyetheramine to the waterborne isobutyl acrylate, stir evenly, and seal for storage.

[0064] The printing ink produced using the method of this invention is immediately sprayed or rolled onto the surface of the printed material after printing. After curing, this allows for better adhesion between the varnish and the printing ink. The adhesion between the ink and the varnish is determined using the pull-off method according to standard ISO4624-2003.

[0065] A transparent substrate with good adhesion to the ink was selected for testing. Printing ink was applied to both sides of the substrate, followed by a gloss coat. The two substrates were then bonded together and cured, and a tensile test was performed using an adhesion tester. The two substrates were fixed to the tension mechanism of the tester and stretched. If the coating detached from the substrate after stretching, the test was considered a failure; if the film separated from the two sides, the test was considered successful. To improve the success rate, the thickness of the printing ink and gloss coat layers was increased to at least 0.3 mm.

[0066] sample Adhesion (MPa) Example 1 2.95±0.3 Example 2 3.23±0.2 Comparative Example 1.98±0.2

[0067] The test results show that adding bisphenol A epoxy resin and polyether diol to the printing ink and adding polyether amine to the varnish can significantly improve the affinity and adhesion between the printing ink and the varnish.

[0068] Although the principles of the present invention have been described in detail above with reference to preferred embodiments, those skilled in the art should understand that the above embodiments are merely illustrative explanations of the implementation of the present invention and are not intended to limit the scope of the present invention. The details in the embodiments do not constitute a limitation on the scope of the present invention. Any obvious changes, such as equivalent transformations or simple substitutions, based on the technical solutions of the present invention without departing from the spirit and scope of the present invention fall within the protection scope of the present invention.

Claims

1. A composition combining printing ink and varnish, wherein the printing ink and varnish are used in combination, characterized in that, When using the printing ink, increasing the screen size increases the ink adhesion. The printing ink comprises: 12g pigment, 18g polyhydroxy monomethacrylate, 15g dimethyl dimethoxysilane, 1g boric acid, 7g bisphenol A epoxy resin, 3g polyether diol, 0.5g dispersant and wetting agent, 0.5g antioxidant, and 25g oil solvent. The varnish comprises: 12g of waterborne polyurethane, 30g of waterborne isobutyl acrylate, 3g of photoinitiator, 10g of polyetheramine, and 0.5g of organic bismuth catalyst. The varnish does not contain epoxy resin, and the printing ink does not contain polyetheramine.

2. The composition of printing ink and varnish according to claim 1, characterized in that, The varnish also includes an ultraviolet absorber.

3. The composition of printing ink and varnish according to claim 1, characterized in that, The pigments include organic pigments and inorganic pigments.

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