Glass printing UV ink and preparation method thereof

Abstract

The invention discloses glass printing UV ink and a preparation method thereof. The ink comprises the following raw materials in percentage by mass: 23-60% of a first monomer, 10-30% of a second monomer, 4-22% of acrylic resin, 0.2-0.7% of an auxiliary agent, 6-10% of a photoinitiator and 5-20% of color paste, one end of the first monomer contains a (methyl) acrylate group, and the other end of the first monomer contains a polar group or / and a non-polar group which can act with glass; the non-polar group is an aromatic ring or an alkyl chain; the second monomer is prepared by esterification reaction of saturated alcohol containing hydroxyl at two ends and (methyl) acrylic acid. The printing ink shows strong adhesive force after being cured on the surface of a glass substrate, and a printed pattern has good weather resistance, toughness and water resistance.

Description

Technical Field

[0001] This invention relates to the field of printing inks, and in particular to a glass printing UV ink and its preparation method. Background Technology

[0002] Glass, as a material possessing both light transmittance and mechanical strength, is increasingly in demand for surface decoration, especially in the field of personalized pattern customization. Traditional glass decoration processes, such as etching, screen printing, and traditional glass oil coating, suffer from long production cycles, complex procedures, high costs for personalized pattern customization, and poor flexibility, making it difficult to meet the modern market's demand for rapid response and diverse designs. UV-curable ink printing technology, with its advantages of fast curing speed, high pattern precision, and environmental friendliness (no VOC emissions), is gradually becoming the mainstream solution for personalized glass surface decoration. However, the smooth surface of glass and its high polarity and low surface energy characteristics present several technical bottlenecks in practical applications of existing UV inks: 1. Existing UV inks have weak adhesion to the glass substrate after curing, making them prone to peeling and detachment. 2. The UV ink cured film layer has insufficient water resistance; prolonged contact with water or cleaning agents can easily lead to swelling, discoloration, and poor weather resistance.

[0003] In view of this, the present invention proposes a glass printing UV ink and its preparation method to solve the above problems. Summary of the Invention

[0004] In order to overcome the shortcomings of the above-mentioned technologies, the present invention provides a glass printing UV ink that exhibits strong adhesion after curing on the surface of a glass substrate, and the printed pattern has good weather resistance, toughness and water resistance.

[0005] To achieve the above objectives, the present invention provides a glass printing UV ink comprising the following raw materials in the indicated mass fractions: 23%–60% first monomer, 10%–30% second monomer, 4%–22% acrylic resin, 0.2%–0.7% additives, 6%–10% photoinitiator, and 5%–20% color paste; the first monomer contains a (meth)acrylate group at one end and a polar group and / or a non-polar group capable of reacting with glass at the other end; the non-polar group is an aromatic ring or an alkyl chain; the second monomer is prepared by reacting a saturated alcohol containing hydroxyl groups at both ends with (meth)acrylate.

[0006] Preferably, the glass printing UV ink comprises the following raw materials by mass fraction: 30%–60% first monomer, 10%–30% second monomer, 10%–22% acrylic resin, 0.2%–0.7% additives, 6%–10% photoinitiator, and 5%–20% color paste; wherein the mass ratio of the first monomer to the second monomer is 1.5–3.5:1.

[0007] Preferably, the polar group of the first monomer is either a carboxyl group or an amino group.

[0008] Preferably, the first monomer comprises one or more of 2-carboxyethyl acrylate, cyclohexyl methacrylate, methacrylate stearate, and o-phenylphenoxyethyl acrylate.

[0009] Preferably, the second monomer includes one or more of polyethylene glycol (400) diacrylate, ethylene glycol dimethacrylate, and 1,4-butanediol dimethacrylate.

[0010] Preferably, the acrylic resin includes one or more of pure acrylic resin, epoxy acrylate, modified acrylic resin, and polyacrylate.

[0011] Preferably, the additive comprises modified polydimethylsiloxane.

[0012] Preferably, the initiator is one or more of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoylphenyl phosphate ethyl ester, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxycyclohexylphenyl ketone, and isopropylthioxanthrone.

[0013] Preferably, the viscosity of the glass printing UV ink is 2 to 100 cPa·s in an environment of 10 to 40°C.

[0014] To achieve the above objectives, the present invention provides a method for preparing UV ink for glass printing, comprising the following steps: adding a first monomer, a second monomer, an acrylic resin, an additive, a photoinitiator, and a color paste into a material tank, stirring for 1 to 3 hours, and then filtering to obtain UV ink.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] 1. The first monomer of this invention contains an acrylate group at one end, which can participate in the curing reaction, and a polar or non-polar group at the other end. The polar group can form hydrogen bonds with glass, improving the adhesion of the ink pattern to the glass surface and solving the problem of easy peeling off of traditional inks. The non-polar group, an aromatic ring or alkyl chain, can improve the waterproof ability of the ink pattern. The second monomer is a cross-linked monomer containing (meth)acrylate groups at both ends, which can form a three-dimensional network structure with the first monomer. Combined with a photoinitiator, it can achieve rapid UV curing. After curing, the film layer has high hardness, good impact resistance, and is not prone to cracking or damage.

[0017] 2. The first monomer, the second monomer, the acrylic resin, the additives, the photoinitiator, and the color paste of the present invention are reasonably proportioned, so that the ink has suitable fluidity. While ensuring adhesion and water resistance, it can prevent the film layer from becoming brittle due to excessive cross-linking and give the cured pattern good toughness. In addition, the additives can improve the leveling and wetting properties of the ink, adapt to the printing requirements of smooth glass surfaces, and ensure the accuracy of the pattern. Detailed Implementation

[0018] The following examples further illustrate the features and other related characteristics of the present invention in detail, to facilitate understanding by those skilled in the art:

[0019] An embodiment of the present invention provides a glass printing UV ink comprising the following raw materials by mass fraction: 23%–60% first monomer, 10%–30% second monomer, 4%–22% acrylic resin, 0.2%–0.7% additives, 6%–10% photoinitiator, and 5%–20% color paste; one end of the first monomer contains a (meth)acrylate group, and the other end contains a polar group and / or a non-polar group capable of reacting with glass; the non-polar group is an aromatic ring or an alkyl chain; the second monomer is obtained by reacting a saturated alcohol containing hydroxyl groups at both ends with (meth)acrylate.

[0020] The first monomer contains a (meth)acrylate group at one end, and contains polar and / or nonpolar groups capable of interacting with glass. The nonpolar groups are aromatic rings or alkyl chains, which can improve the water resistance of the printed pattern.

[0021] The second monomer is prepared by esterification of a saturated alcohol containing hydroxyl groups at both ends with (meth)acrylate, resulting in acrylate groups at both ends of the second monomer. The first monomer contains a (meth)acrylate group at one end. Combined with a photoinitiator, it undergoes rapid UV curing, polymerizing to form a three-dimensional network structure of ink patterns. The cured ink film exhibits higher hardness, abrasion resistance, and impact resistance, while maintaining flexibility and avoiding brittleness caused by excessive cross-linking. Compared to photopolymerization using monomers containing only one acrylate group, which results in a linear polymer with low cross-linking density, a softer film, and poorer scratch and stain resistance, this method yields a superior solution.

[0022] In some embodiments, the glass printing UV ink comprises the following raw materials by mass fraction: 30%–60% first monomer, 10%–30% second monomer, 10%–22% acrylic resin, 0.2%–0.7% additives, 6%–10% photoinitiator, and 5%–20% color paste; wherein the mass ratio of the first monomer to the second monomer is 1.5–3.5:1.

[0023] In some embodiments, the polar group of the first monomer is either a carboxyl group or an amino group. The carboxyl group can combine with the hydroxyl groups on the glass surface; the amino group is highly polar and can generate strong hydrogen bonds and van der Waals forces with substances such as glass, thereby enhancing the adhesion between the ink and the glass.

[0024] In some embodiments, the first monomer comprises one or more of 2-carboxyethyl acrylate, cyclohexyl methacrylate, methacrylate stearate, and o-phenylphenoxyethyl acrylate.

[0025] In some embodiments, the second monomer includes one or more of polyethylene glycol (400) diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, and ethylene glycol dimethacrylate.

[0026] In some embodiments, the acrylic resin includes one or more of pure acrylic resin, epoxy acrylate, modified acrylic resin, and polyacrylate, which can further improve the weather resistance and mechanical strength of the cured ink. Moreover, the viscosity of the acrylic resin is greater than that of the first monomer and the second monomer, and the ratio of the acrylic resin to the first and second monomers allows the ink to reach a suitable application range. The acrylic resin contains unsaturated bonds, enabling it to polymerize with the first and second monomers to form a three-dimensional network structure, further improving the density of the patterned film layer.

[0027] In some embodiments, the additive includes modified polydimethylsiloxane, which can reduce the surface tension of the ink, enabling the ink to spread quickly on the glass surface, reducing uneven coating caused by poor substrate wettability, and ensuring that the printed pattern is flat and smooth.

[0028] In some embodiments, the adjuvant may be one or more of the commercially available BYK371, BYK373, BYK377, BYK378, BYK3700, BYK3710, AFCONA3030, AFCONA3034, AFCONA3037, AFCONA3230, and AFCONA3250.

[0029] In some embodiments, the initiator is one or more of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoylphenyl phosphate ethyl ester, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxycyclohexylphenyl ketone, and isopropylthioxanthrone.

[0030] In some embodiments, the viscosity of the glass printing UV ink is 10-1500 cPa·s in an environment of 20-30°C, which has high fluidity and is suitable for UV printers to print patterns by inkjet.

[0031] An embodiment of the present invention provides a method for preparing UV ink for glass printing, comprising the following steps: adding a first monomer, a second monomer, an acrylic resin, an additive, a photoinitiator, and a color paste into a material tank, stirring for 1 to 3 hours, and then filtering to obtain UV ink.

[0032] Example 1 of the present invention provides a glass printing UV ink, the preparation method of which includes the following steps:

[0033] Step 1: Add 5.5g color paste, 23g o-phenylphenoxyethyl acrylate, 30g stearic acid methacrylate, 20.8g ethylene glycol dimethacrylate, 4g epoxy acrylate, 7.3g 1,4-butanediol dimethacrylate, 0.4g BYK375, 5g 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and 4g isopropylthioxanthraquinone to the mixing tank in sequence. Stir for 2 hours, then filter to obtain UV ink.

[0034] Examples 2-5 and Comparative Examples 1-4 were prepared by changing the raw material formula according to Table 1 and following the preparation method of Example 1.

[0035] Table 1 shows the formulations of Examples 1-5 and Comparative Examples 1-4.

[0036]

[0037]

[0038] The inks prepared in Examples 1-5 and Comparative Examples 1-4 were added sequentially to a UV printer, and patterns were printed on clean glass. After curing for 5 seconds, the printed patterns underwent the following performance tests:

[0039] (1) Adhesion test: After applying 3M tape, quickly peel it off and observe the ink peeling off within the squares. Rating standards: 0 (no peeling), 1 (peeling area < 5%), 2 (peeling area 5%-15%), 3 (peeling area 15%-30%), 4 (peeling area 30%-50%), 5 (peeling area > 50%).

[0040] (2) Water resistance test: Immerse the glass sample with the printed pattern in distilled water at 25℃, and take it out after one day, three days and seven days respectively, and observe whether the pattern film layer shows swelling, discoloration or peeling. Rating standard: Excellent (no change), Good (slight discoloration, no swelling / peeling), Medium (significant swelling, no peeling), Poor (peeling or severe swelling).

[0041] (3) Scratch resistance test: Using a pencil hardness tester (refer to GB / T 6739 standard), pencils of different hardness (from 6B to 9H) were used to scratch the film surface at a 45° angle and with a force of 500g. The highest pencil hardness level that did not produce obvious scratches was recorded.

[0042] (4) Flexibility test: Spray ink onto curved glass to form a pattern, and observe whether the film layer cracks or peels off. Rating criteria: Good (no cracking or peeling after printing on curved glass), Average (slight cracking), Poor (cracking or peeling off).

[0043] Table 2 shows the test results of Examples 1-5 and Comparative Examples 1-4.

[0044]

[0045]

[0046] (1) As can be seen from the above, compared with Comparative Examples 1 to 4, the patterned film layers formed in Examples 1 to 5 have good adhesion. This is because some of the first monomers contain polar groups, which can form stable hydrogen bonds with the hydroxyl groups on the glass surface, thereby improving the bonding force between the ink-cured film and the glass substrate.

[0047] (2) The three-dimensional network structure formed by the polymerization of the second monomer, the first monomer, and the acrylic resin in Examples 1-5 further improves the density of the patterned film layer, resulting in a patterned film layer with good mechanical strength, scratch resistance, and water resistance. At the same time, some of the first monomers contain non-polar groups (aromatic rings or alkyl chains), which are hydrophobic and can block water molecules from penetrating, reducing water intrusion.

[0048] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A UV ink for glass printing, characterized in that, The raw materials include the following mass fractions: 23%–60% first monomer, 10%–30% second monomer, 4%–22% acrylic resin, 0.2%–0.7% additives, 6%–10% photoinitiator, and 5%–20% color paste; one end of the first monomer contains a (meth)acrylate group, and the other end contains a nonpolar group and / or a polar group capable of interacting with glass; the nonpolar group is an aromatic ring or an alkyl chain; the second monomer is prepared by esterification reaction of a saturated alcohol containing hydroxyl groups at both ends with (meth)acrylate.

2. The UV ink for glass printing according to claim 1, characterized in that, The raw materials include the following mass fractions: 30%–60% first monomer, 10%–30% second monomer, 10%–22% acrylic resin, 0.2%–0.7% additives, 6%–10% photoinitiator, and 5%–20% color paste; wherein the mass ratio of the first monomer to the second monomer is 1.5–3.5:

1.

3. The UV ink for glass printing according to claim 1, characterized in that, The polar group of the first monomer is either a carboxyl group or an amino group.

4. The UV ink for glass printing according to claim 1, characterized in that, The first monomer includes one or more of 2-carboxyethyl acrylate, cyclohexyl methacrylate, stearic acid methacrylate, and o-phenylphenoxyethyl acrylate.

5. The UV ink for glass printing according to claim 1, characterized in that, The second monomer includes one or more of polyethylene glycol (400) diacrylate, ethylene glycol dimethacrylate, and 1,4-butanediol dimethacrylate.

6. The UV ink for glass printing according to claim 1, characterized in that, The acrylic resins include one or more of pure acrylic resin, epoxy acrylate, modified acrylic resin, polyacrylate, and modified polyacrylate.

7. The UV ink for glass printing according to claim 1, characterized in that, The additives include modified polydimethylsiloxane.

8. The UV ink for glass printing according to claim 1, characterized in that, The initiator is one or more of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoylphenyl phosphate ethyl ester, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxycyclohexylphenyl ketone, and isopropylthioxanthrone.

9. A glass printing UV ink according to claim 1, characterized in that, The viscosity is 2–100 cPa·s in an environment of 10–40℃.

10. A method for preparing a glass printing UV ink as described in any one of claims 1 to 9, characterized in that, Includes the following steps: The first monomer, the second monomer, acrylic resin, additives, photoinitiator, and color paste are added to the material tank and stirred for 1 to 3 hours. The mixture is then filtered to obtain UV ink.

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