CN114891393B

CN114891393B - UV (ultraviolet) ink for measuring tape, preparation method of UV ink and measuring tape

Info

Publication number: CN114891393B
Application number: CN202210553707.XA
Authority: CN
Inventors: 王策鑫; 龚博; 李新寅
Original assignee: Guangdong Arojet Ink Jet Technology Co ltd
Current assignee: Guangdong Arojet Ink Jet Technology Co ltd
Priority date: 2022-05-19
Filing date: 2022-05-19
Publication date: 2023-07-07
Anticipated expiration: 2042-05-19
Also published as: CN114891393A

Abstract

The invention relates to UV (ultraviolet) ink for a tape measure, a preparation method thereof and the tape measure, wherein the UV ink comprises the following raw materials in parts by weight: 60-80 parts of modified epoxy acrylate resin, 5-8 parts of first monomer, 10-15 parts of second monomer, 3-5 parts of photoinitiator, 1-2 parts of cationic initiator and 5-15 parts of pigment; the modified epoxy acrylate resin is obtained by reacting epoxy resin, hydroxyl-terminated dimethylpolysiloxane and pentaerythritol with acrylic acid; the structural formula of the first monomer is R ₁ ‑A‑R ₂ Wherein A is a polyether, polyether or polyurethane segment; r is R ₁ Is acrylate, R ₂ Is epoxy or oxetane; the second monomer is polyfunctional acrylate. The UV ink provided by the invention has the advantages of quick curing time, high adhesive force after being cured when being used for a tape measure, and good weather resistance.

Description

UV (ultraviolet) ink for measuring tape, preparation method of UV ink and measuring tape

Technical Field

The invention belongs to the technical field of UV (ultraviolet) light curing, and particularly relates to UV (ultraviolet) ink for a tape measure, a preparation method of the UV ink and the tape measure.

Background

The tape measure is a common measuring tool, is used as a low-value and easy-to-consume tool in the industries of processing, manufacturing, building, decoration and the like, and has the requirements of huge consumer groups and sustainability. In the prior art, the production process of the tape measure needs to be performed with printing primer, plate making, plate pasting, scale character printing and the like, the process is complex, the plate making and plate pasting process has high technical requirements, the whole tape measure cannot be used due to slight error of plate pasting, and more waste is caused; the paint used in the printing process has large smell, is not environment-friendly, and the printing ink has poor quality and poor printing effect.

The UV ink has the characteristics of environmental friendliness, no solvent emission, safe and reliable use, high efficiency, good printing quality, strong adaptability and the like, is a novel environment-friendly ink which is very popular at present and has very high attention, and has very good development prospect. UV inks generally use oligomers or monomers of acrylate or vinyl reactive groups, with fast curing times, up to 1 second at maximum. The UV printing ink mainly comprises an oligomer (prepolymer), a monomer, a reactive diluent, an initiator, a dye and an auxiliary agent, wherein the oligomer which is most widely used at present is epoxy acrylate resin. However, epoxy acrylate resins have the following disadvantages: 1) The resin has certain skin irritation, is unfavorable to construction operation, and is not green; 2) The resin has high viscosity, and can be used after being diluted by a large amount of reactive diluents, but the curing speed and the adhesive force of the UV ink can be corresponding under the condition that the amount of the reactive diluents is large; 3) The epoxy acrylate resin contains epoxy groups, benzene rings and other groups with larger polarity, and has larger rigidity, insufficient toughness and poor weather resistance; 4) The ester carbonyl of the polypropylene ester chain segment can lead to partial ester group fracture under the irradiation of strong ultraviolet, especially bisphenol A epoxy acrylate resin, and the aging occurs under the existence of oxygen to generate the phenomenon of yellow index increase. When UV ink is used for a tape measure, if weather resistance is poor, adhesion of a UV ink coating is reduced in use with time, such as in a high-temperature and high-humidity environment, or in some acid/alkali chemical environments, so that the color of the tape measure is light, or abrasion occurs, the service life of the tape measure is directly reduced, or the service effect of the tape measure is affected.

CN114213899a discloses a polyether modified polyurethane UV ink, wherein polyether modified polyurethane acrylate is obtained by reacting polyether with toluene diisocyanate and then reacting with hydroxypropyl acrylate, and has rigid urethane bond and aromatic ring, and also has a flexible segment of polyether, and has better toughness. However, weather resistance and durability have yet to be improved.

CN113416448A discloses a UV ink, which uses epoxy acrylate as a main prepolymer, and has the advantages of fast curing rate, strong adhesive force and flexibility. However, the disadvantages of such prepolymers have not been overcome due to their direct use of epoxy acrylate resins.

Disclosure of Invention

In order to solve the technical problems that the comprehensive performances of the UV ink for the tape measure in the prior art such as adhesive force, weather resistance and curing speed are not satisfactory, the invention provides the UV ink for the tape measure, which achieves the purposes of lower viscosity under the condition of lower consumption of active diluents by selecting modified epoxy acrylate resin, monomers and an initiator, has excellent weather resistance and adhesive force indexes after quick curing, and is novel and has market prospect.

The invention provides UV ink for a tape measure, which comprises the following raw materials in parts by weight: 60-80 parts of modified epoxy acrylate resin, 5-8 parts of first monomer, 10-15 parts of second monomer, 3-5 parts of photoinitiator, 1-2 parts of cationic initiator and 5-15 parts of pigment; the modified epoxy acrylate resin is obtained by reacting epoxy resin, hydroxyl-terminated dimethylpolysiloxane and pentaerythritol with acrylic acid; the structural formula of the first monomer is R ₁ -A-R ₂ Wherein A is a polyether, polyether or polyurethane segment; r is R ₁ Is acrylate, R ₂ Is epoxy or oxetane; the second monomer is polyfunctional acrylate.

Further, in the modified epoxy acrylate resin, the data molecular weight of the hydroxyl-terminated dimethyl polysiloxane is 500-1000, the epoxy resin is at least one of bisphenol type epoxy resin, such as bisphenol A epoxy resin, bisphenol AF epoxy resin and bisphenol S epoxy resin, and the epoxy value of the epoxy resin is 0.2-0.4; the molar ratio of the epoxy resin to the hydroxyl-terminated dimethylpolysiloxane to the pentaerythritol to the acrylic acid is 100:4-8:1-1.5:160-180.

Further, the modified epoxy acrylate resin is prepared by a preparation method comprising the following steps: uniformly mixing epoxy resin, hydroxyl-terminated dimethylpolysiloxane, pentaerythritol and a catalyst in an inert atmosphere, heating to 60-70 ℃ for reaction for 3-5h, adding a polymerization inhibitor, slowly adding acrylic acid, after dripping in 1-2h, heating to 80-90 ℃ by changing a door, and cooling and discharging when the reaction acid value is less than 5mg KOH/g to obtain the modified epoxy acrylate resin.

Further, in the above-mentioned preparation method of the modified epoxy acrylate resin, a catalyst for the reaction between an epoxy group and a hydroxyl group is well known in the art, such as at least one of triethylamine, N-dimethylbenzylamine, tetraethylammonium bromide, tetrabutylammonium bromide, triphenylphosphine, chromium acetylacetonate, the amount of the catalyst being 1 to 2wt% based on the mass of the epoxy resin; the polymerization inhibitor is used for preventing unsaturated double bonds of acrylic acid from polymerizing, such as hydroquinone, 2, 5-dimethyl hydroquinone and 2, 6-di-tert-butyl-p-cresol, and the addition amount is 0.1-0.5wt% of the mass of the acrylic acid.

Further, the first monomer is at least one selected from 3, 4-epoxycyclohexyl methacrylate (TTA 15), 3, 4-epoxycyclohexyl methacrylate (TTA 16), oxetane methacrylate (THM 202) and ethyl 2-ethyleneoxyethoxyacrylate (VEEA).

Further, the polyfunctional acrylate is selected from the group consisting of bicyclodecane diacrylate, 1,6 hexanediol diacrylate (HDDA), hexanediol ethoxy diacrylate, butanediol diacrylate (BDDA), dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), tricyclodecane diacrylate, tricyclodecane dimethanol diacrylate, alkoxylated hexanediol diacrylate, trimethylolpropane triacrylate (TMPTA), pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate (TMPTA), glycerol Propoxylate Triacrylate (GPTA); at least one of pentaerythritol tetraacrylate, pentaerythritol ethoxytetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate (DPHA) and sorbitol pentaacrylate.

Preferably, the average functionality of the multi-functional acrylate is 3-4, preferably 3.2-3.6. The definition of the average functionality is the amount of functional group total of acrylate dosed/the amount of acrylate total. Wherein the functional group of the multi-functional acrylate is only allyl.

Still more preferably, the multi-functionality acrylate is a combination of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate, and the molar content of sorbitol pentaacrylate is 10-30mol% of the multi-functionality acrylate. The ethoxylated trimethylolpropane triacrylate and the sorbitol pentaacrylate are selected as the second monomer, so that the adhesive has the advantages of low irritation, no pungent smell and friendly construction.

The inventor unexpectedly discovers that the modified epoxy acrylate resin and the sorbitol pentaacrylate have a certain synergistic compounding effect, and the modified epoxy acrylate resin and the sorbitol pentaacrylate have the beneficial effects of high curing speed, good weather resistance after curing and high adhesive force by being matched with a proper type of initiator under the condition that the average functionality of the polyfunctional acrylate meets the conditions.

The photoinitiator is at least one selected from alpha-hydroxyketone and acyl-containing phosphine, and is specifically at least one selected from benzophenone, 2-isopropyl thioxanthone and diphenyl (2, 4, 6-Trimethylbenzoyl) Phosphine Oxide (TPO); the cationic initiator is selected from at least one of diazonium salt, diaryl iodonium salt, triaryl sulfonium salt, alkyl sulfonium salt, iron aryl salt, sulfonyloxy ketone and triaryl siloxane ether, preferably 4,4' -dimethyl diphenyl iodonium salt hexafluorophosphate (PI-880).

Preferably, the photoinitiator is diphenyl (2, 4, 6-Trimethylbenzoyl) Phosphine Oxide (TPO) and the cationic initiator is 4,4' -dimethyldiphenyliodonium hexafluorophosphate (PI-880). The two components are matched, so that the fast surface layer curing speed and the enhanced deep layer curing strength can be provided, and the adhesive force is enhanced.

Further, the pigment is various pigments commonly used in the market, such as black pigment carbon black; red pigments 57:1, 53:1, 146, 122, 184, 176, 254, etc.; yellow pigments 12, 13, 14, 74, 150, 151, 180, etc.; blue pigment 15:3, 15:4, etc.; white pigments such as titanium dioxide, barium sulfate, calcium carbonate, talc, kaolin, silica, and the like.

Further, the UV ink for the tape measure also comprises auxiliary agents known in the art, such as dispersing agents, leveling agents, wetting agents, antifoaming agents, polymerization inhibitors and sensitizers. The types and amounts thereof are well known in the art. In one embodiment of the present invention, the sensitizer is TR-PSS-303 in an amount of 0.1 to 0.3 parts; the leveling agent is BYK-3510 with the dosage of 0.1-0.3 part, the defoamer is BYK-055 with the dosage of 0.05-0.1 part, the dispersant is Solsperse24000 with the dosage of 0.1-0.2 part.

The second object of the invention is to provide a method for preparing the UV ink for the tape measure, which comprises the following steps:

(T1) weighing the modified epoxy acrylate resin, the first monomer, the second monomer, the photoinitiator and the cationic initiator according to parts by weight, and optionally adding an auxiliary agent and uniformly mixing;

and (T2) adding pigment into the mixture obtained in the step (T1), and continuing stirring to uniformly disperse the pigment to obtain the UV ink for the tape measure.

The first monomer and the second monomer of the ink are equivalent to reactive diluents, so that solvents are not needed to be added when the UV ink is prepared, the ink is environment-friendly, the operation is odorous, the irritation is small, and the safety is high.

A third object of the present invention is to provide a tape measure obtainable by a preparation process comprising the steps of:

(S1) placing the tape in a discharging area and conveying the tape to a primer spraying area;

(S2) sequentially spraying the UV tape measure ink to the front and back sides of the tape in a primer spraying area to form scales and characters and carrying out ultraviolet curing;

and (S3) conveying the solidified tape to a receiving area to realize receiving, thus obtaining the tape.

Further, in the step (S2), the ultraviolet curing condition is that the ultraviolet energy is 20000 to 30000mJ/cm ² The curing time is 0.5-1s.

Specifically, the front and back sides of the tape measure can be printed according to the actual condition of the tape measure, the printing data is controlled by computer printing software, a engraving plate is not needed, PDF is led in to be printed, and specific characters or scales can be directly printed. The intelligent digital spray printing mode is adopted, the spray head can be flexibly adjusted, the effect is more refined, and the precision is higher; flexible spray printing can be realized, and the spray printing is local, comprehensive and unlimited in color. Specifically, the computer spray printing software is only required to be conventional spray printing software, and the invention is not particularly limited. The printing ink is controlled by the computer printing system, so that plate making is not needed, the number of equipment is reduced, the requirements on technicians are also reduced, and the labor cost can be reduced.

According to the preparation process, the special UV ink is selected when the primer, the scales and the characters are printed, and optionally, a layer of gloss oil can be finally sprayed, so that the effect of protecting the primer and the scale layers of the previous two spraying processes can be achieved, the scratch resistance of the tape measure is further improved, the overall brightness is higher, the color is more protected, and the grade is improved from the aspect of visual effect of appearance. Meanwhile, for the steel tape, the sharpness of the surface of the steel tape is reduced, and the use safety is higher. The tape preparation process has no limitation on the production material of the tape, and can be used for steel tape, cloth tape, leather tape and the like, the width and the length of the tape are not limited, and various specifications and dimensions are feasible.

And detecting the jet printing effect after curing, including detecting the quality of the jet printing primer, the scales and the characters, and detecting the integrity of the jet printing, such as whether ink is broken, whether the continuity of the scales and the characters is continuous, whether the jet printing characters have errors, and the like. The quality of the spray printing effect can be rapidly identified through visual detection in the preparation process, unqualified products are removed, and the unqualified products are marked without manual detection, so that the speed is higher.

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

1. according to the UV ink with a specific formula, the modified epoxy acrylate resin, the polyfunctional acrylate comprising sorbitol pentaacrylate and the initiator are compounded, so that the beneficial effects of quick curing time, high adhesive force after curing and good weather resistance are achieved.

2. According to the tape preparation process using the UV tape ink, the specific UV tape ink is adopted, corresponding ink is adopted when the primer is sprayed and printed, the scales and the characters are sprayed and printed, and the ultraviolet curing process is combined, so that the adhesive force of the ink is high, the ink is not easy to hang off, no pungent smell is generated during spraying and printing, and the environment-friendly performance is good; meanwhile, when the scales and the characters are printed, the intelligent digital printing technology is adopted, and the ink can be directly printed on the tape, so that the common etching process in the prior art is avoided, and the method is simple and convenient. The UV tape ink has the advantages of high tape curing speed, good wear resistance and flexibility, no VOC, small smell, safety and good environmental protection through the curing function of the initiator containing free radicals and cations.

Detailed Description

The invention is further illustrated below in connection with specific examples, but is not limited to the disclosure. Unless otherwise specified, "parts" are parts by weight in the examples of the present invention. All reagents used are those commercially available in the art.

Preparation example 1

Under inert atmosphere, bisphenol S epoxy resin with an epoxy value of 0.31, hydroxyl-terminated dimethyl silane with a number average molecular weight of about 700 and pentaerythritol are added into a reaction container, tetrabutylammonium bromide is added as a catalyst, butyl acrylate is added as a solvent, wherein the molar ratio of the bisphenol S epoxy resin to the hydroxyl-terminated dimethyl silane to the pentaerythritol is 100:5:1.2, tetrabutylammonium bromide is added in an amount of 1 weight percent of bisphenol S epoxy resin, the mixture is uniformly mixed under stirring, then the temperature is raised to 70 ℃, the reaction is carried out for 5 hours, 2, 5-dimethyl hydroquinone is added as a polymerization inhibitor, acrylic acid is slowly added through a metering pump, the temperature is raised to 85 ℃, when the system acid value is less than 5mg KOH/g, the reaction is carried out, the material is cooled and discharged, and the modified epoxy acrylate resin is obtained, wherein the molar ratio of the acrylic acid to the bisphenol S epoxy resin to the acrylic acid is 170:100, and the addition amount of the polymerization inhibitor is 0.5wt% of the mass of the acrylic acid.

Preparation example 2

Other conditions and operations are the same as in preparation example 1, except that the molar ratio of bisphenol S epoxy resin, hydroxyl-terminated dimethylsilane, pentaerythritol and acrylic acid as raw materials is 100:4:1.5:170.

preparation example 3

Other conditions and operations are the same as in preparation example 1, except that the molar ratio of bisphenol S epoxy resin, hydroxyl-terminated dimethylsilane, pentaerythritol and acrylic acid as raw materials is 100:8:1:170.

preparation example 4

Other conditions and operations are the same as in preparation example 1, except that the starting bisphenol S epoxy resin is replaced with an equimolar amount of bisphenol A epoxy resin of equal epoxy value.

Comparative preparation example 1

Other conditions and operations were the same as in preparation example 1, except that the hydroxyl-terminated dimethylsilane was replaced with PEG having a number average molecular weight of 800, and the molar ratio of bisphenol S epoxy resin, PEG, pentaerythritol and acrylic acid as raw materials was 100:5:1.2:170.

comparative preparation example 2

Other conditions and operations are the same as in preparation example 1 except that no hydroxyl-terminated dimethylsilane is added, and the molar ratio of bisphenol S epoxy resin, pentaerythritol and acrylic acid as raw materials is 100:8:170.

comparative preparation example 3

Other conditions and operations were the same as in preparation example 1 except that pentaerythritol was not added, and the molar ratio of bisphenol S epoxy resin, hydroxyl-terminated dimethylsilane, and acrylic acid as raw materials was 100:1.5:180.

example 1

(T1) 60 parts of the modified epoxy acrylate resin prepared in preparation example 1,6 parts of first monomer 3, 4-epoxycyclohexyl methacrylate and 12 parts of second monomer, wherein the second monomer is a compound of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate according to a molar ratio of 8:2, the average functionality of the second monomer is 3.4,4 parts of photoinitiator TPO,1.5 parts of cationic initiator PI-880,0.1 parts of TR-PSS-303,0.1 parts of BYK-3510,0.05 parts of BYK-055,0.1 parts of Solsperse24000.

And (T2) adding 10 parts of carbon black serving as a pigment into the mixture obtained in the step (T1), and fully stirring to uniformly mix and disperse the pigment to obtain the UV ink.

Examples 2 to 4, comparative examples 1 to 3

Other conditions and operations were the same as in example 1 except that epoxy acrylate resins were prepared in preparation examples 2 to 4 and comparative preparation examples 1 to 3, respectively.

Example 5

Other conditions and operations were the same as in example 1 except that the first monomer was 3, 4-epoxycyclohexyl methacrylate, the second monomer was a combination of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate in a molar ratio of 7:3, and the second monomer had an average functionality of 3.6.

Example 6

Other conditions and operations were the same as in example 1 except that the second monomer was a combination of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate in a molar ratio of 9:1, the second monomer having an average functionality of 3.2.

Example 7

Other conditions and operations were the same as in example 1 except that the second monomer was a combination of ethoxylated trimethylolpropane triacrylate and dipentaerythritol pentaacrylate in a mole ratio of 8:2, with an average functionality of 3.4.

Example 8

Other conditions and operations were the same as in example 1 except that the second monomer was a combination of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate in a molar ratio of 6:4, the second monomer having an average functionality of 3.8.

Example 9

Other conditions and operations were the same as in example 1 except that the second monomer was a combination of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate in a molar ratio of 15:1, the second monomer having an average functionality of 3.12.

Example 10

Other conditions and operations were the same as in example 1 except that the second monomer was a tripropylene glycol diacrylate and sorbitol pentaacrylate in a 1:1 molar ratio, the second monomer having an average functionality of 3.5.

Example 11

Other conditions and operations were the same as in example 1 except that no cationic initiator was added and the amount of photo initiator TPO was 5.5 parts.

Application example

(S2) sequentially spraying the UV tape measure ink of the embodiment on the front surface and the back surface of the tape in a primer spraying area to form scales and characters and carrying out ultraviolet curing; the ultraviolet curing condition is that the ultraviolet energy is 20000mJ/cm ² The curing time was 1s.

The format-strong UV inks were tested for performance and the results are shown in table 1 below:

cure speed-test on aluminum.

Solvent-resistant wiping: acetone is used as a wiping solvent, soft cloth dipped with the acetone is used for wiping back and forth with moderate force, and the wiping times are the times when the coating begins to fall off.

Viscosity: the test was performed at 25℃using an NDJ-1 rotational viscometer.

Flexibility: referring to a standard GB/T1731-1993 paint film flexibility measurement method, UV ink is sprayed on tin plate with the size of 120mmx50mmx0.3mm, after UV curing, the ink layer of a sample is upwards, a cylindrical rod with different diameters is bent for about 180 degrees, and after bending, a magnifying glass is used for observing whether the surface of the coating has the phenomena of reticulate patterns, cracks, flaking and the like. The diameters of the round bars are 1mm, 2mm, 3mm, 4mm and 5mm respectively. The ink layers are sequentially rated 5, preferably 1, as measured by minimum diameter.

Adhesion force: with reference to standard GB/T9286-1998, the base plate is an aluminum material, tested by the hundred-cell method. The adhesion was graded according to 0-5, with 0 being the best and 5 being the worst.

Acid resistance: the solidified film was immersed in 10wt% diluted hydrochloric acid for 48 hours, taken out, washed with water, dried and retested for adhesion.

Alkali resistance: the solidified film was immersed in 10wt% naoh for 48 hours, taken out, washed with water, dried and retested for adhesion.

Table 1 UV ink Performance test results

As can be seen from the data in Table 1, the UV ink for the tape measure prepared by the invention has excellent comprehensive performance, and the modified epoxy acrylate resin and the monomer comprising sorbitol pentaacrylate are adopted, so that the UV ink has high curing speed, excellent flexibility, adhesion and weather resistance after curing, and is suitable for the tape measure. The UV ink used as the tape measure has clear scale marks on a long-time scale, is acid and alkali resistant, and prolongs the service life of the tape measure.

Claims

1. The UV ink for the tape measure is characterized by comprising the following raw materials in parts by weight: 60-80 parts of modified epoxy acrylate resin, 5-8 parts of first monomer, 10-15 parts of second monomer, 3-5 parts of photoinitiator, 1-2 parts of cationic initiator and 5-15 parts of pigment; the modified epoxy acrylate resin is obtained by reacting epoxy resin, hydroxyl-terminated dimethylpolysiloxane and pentaerythritol with acrylic acid; the first monomer is at least one selected from 3, 4-epoxy cyclohexyl methacrylate, 3, 4-epoxy cyclohexyl methacrylate and oxetane methacrylate; the second monomer is polyfunctional acrylate, the polyfunctional acrylate is the compound of ethoxylated trimethylolpropane triacrylate and sorbitol pentaacrylate, and the molar content of the sorbitol pentaacrylate accounts for 10-30mol% of the polyfunctional acrylate;

in the modified epoxy acrylate resin, the number average molecular weight of the hydroxyl-terminated dimethyl polysiloxane is 500-1000, the epoxy resin is bisphenol type epoxy resin, and the epoxy value of the epoxy resin is 0.2-0.4; the molar ratio of the epoxy resin to the hydroxyl-terminated dimethylpolysiloxane to the pentaerythritol to the acrylic acid is 100:4-8:1-1.5:160-180;

the photoinitiator is diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide, and the cationic initiator is 4,4' -dimethyl diphenyl iodonium hexafluorophosphate.

2. The UV ink for a tape measure according to claim 1, wherein the bisphenol type epoxy resin is at least one selected from bisphenol a epoxy resin, bisphenol AF epoxy resin, bisphenol S epoxy resin.

3. The UV ink for a tape measure according to claim 1, wherein the modified epoxy acrylate resin is prepared by a preparation method comprising the steps of: uniformly mixing epoxy resin, hydroxyl-terminated dimethylpolysiloxane, pentaerythritol and a catalyst in an inert atmosphere, heating to 60-70 ℃ for reaction for 3-5h, adding a polymerization inhibitor, slowly adding acrylic acid, after dropwise adding in 1-2h, slowly heating to 80-90 ℃ and cooling and discharging when the reaction acid value is less than 5mg KOH/g, thus obtaining the modified epoxy acrylate resin.

4. The UV ink for a measuring tape according to claim 3, wherein the catalyst is at least one selected from the group consisting of triethylamine, N-dimethylbenzylamine, tetraethylammonium bromide, tetrabutylammonium bromide, triphenylphosphine, chromium acetylacetonate, and the amount of the catalyst is 1 to 2wt% based on the mass of the epoxy resin; the polymerization inhibitor is at least one selected from hydroquinone, 2, 5-dimethyl hydroquinone and 2, 6-di-tert-butyl-p-cresol, and the addition amount is 0.1-0.5wt% of the mass of the acrylic acid.

5. A method of preparing the UV ink for tape measures as claimed in any one of claims 1 to 4, comprising the steps of:

(T1) weighing the modified epoxy acrylate resin, the first monomer, the second monomer, the photoinitiator and the cationic initiator according to parts by weight, and uniformly mixing;

6. A tape measure obtainable by a preparation process comprising the steps of:

(S2) sequentially printing the UV tape ink of any one of claims 1-4 on the front and back sides of the tape in a primer printing zone to form graduations and text and UV curing;

7. The tape measure of claim 6, wherein in step (S2), the ultraviolet curing conditions are ultraviolet light energy of 20000 to 30000mJ/cm ² The curing time is 0.5-1s.