Water-based high-essential oil ink for integrated stenograph and preparation method of water-based high-essential oil ink

Abstract

The invention relates to the technical field of printing ink, in particular to water-based high-essential oil ink for an integrated stenograph and a preparation method of the water-based high-essential oil ink. The preparation method of the water-based high-essential oil ink for the integrated stenograph comprises the following steps: obtaining an oil phase which is obtained by mixing qualified base ink and kerosene; the preparation of the qualified base ink comprises the following steps: sequentially mixing, dispersing and grinding machine oil, kerosene, an emulsifier, resin and a pigment to enable the fineness of the obtained base ink to reach 5-10 microns, and then storing the base ink in a sealed manner to obtain the qualified base ink; obtaining a water phase, wherein the water phase is obtained by mixing water, glycerol, electrolyte and a preservative; and mixing and emulsifying the water phase and the oil phase. The water-based high-essential oil ink for the integrated stenograph provided by the invention is high in printing definition, low in ink consumption, good in back dirt and high in stability.

Description

Technical Field

[0001] The invention relates to the technical field of printing ink, and in particular to a water-based high-precision ink for an integrated quick-printing machine and a preparation method thereof. Background Art

[0002] The digital integrated quick printing machine is a mimeographing device that integrates plate making and printing. It has been widely used in places with large printing volumes such as schools, government agencies, and printing shops. It is convenient, fast, environmentally friendly, and economical. The printing process of the digital integrated quick printing machine is similar to that of electric ink printing. During printing, the front edge of the cardboard perforated by the thermal head is transported to the paper clamp of the printing drum unit and clamped. As the drum rotates, it hangs on the surface of the drum. The printing paper is sent to the bottom of the drum by the paper feeding mechanism. After alignment, it is in close contact with the cardboard on the drum. The ink roller in the drum is tightly pressed against the inner surface of the cardboard (with media such as polytetrafluoroethylene and stainless steel mesh in between), and the ink is printed on the paper through the image holes on the cardboard, completing the printing process. Finally, the separation claw and fan are used to blow air to separate the printed paper from the drum and send it to the paper receiving table to complete the printing process.

[0003] The ink used in digital integrated quick printing machines is an oil-in-water aqueous ink, which is odorless and environmentally friendly. However, the viscosity of existing inks varies greatly in summer and winter, and it is difficult to ensure the stability of viscosity under temperature fluctuations. This will result in different finished products printed with the same ink in summer and winter. Summary of the invention

[0004] In order to solve the above-mentioned deficiencies in the prior art, the present invention provides a water-based high-precision ink for an integrated quick-printing machine and a preparation method thereof.

[0005] In order to solve the above technical problems, one of the technical solutions provided by the present invention is as follows:

[0006] A method for preparing water-based high-precision ink for an integrated quick-printing machine, the method comprising:

[0007] Obtaining an oil phase, wherein the oil phase is obtained by mixing a qualified base ink with kerosene;

[0008] The preparation of the qualified base ink comprises mixing, dispersing and grinding machine oil, kerosene, emulsifier, resin and pigment in sequence, so that the fineness of the obtained base ink reaches 5 to 10 μm, and then the base ink is sealed and stored to obtain the qualified base ink;

[0009] obtaining an aqueous phase, wherein the aqueous phase is obtained by mixing water, glycerin, electrolytes and preservatives;

[0010] The water phase and the oil phase are mixed and emulsified.

[0011] In one embodiment, the resin is selected from any one of rosin resin, rosin-modified resin, phenolic resin, petroleum resin, or a mixture thereof.

[0012] In one embodiment, the molecular weight of the resin is between 10,000 and 100,000; preferably, the molecular weight of the resin is between 30,000 and 50,000.

[0013] In one embodiment, relative to 10 kg of kerosene used to prepare the base ink, the amount of the pigment is 15-30 kg, the amount of the emulsifier is 10-20 kg, the amount of the machine oil is 50-100 kg, and the amount of the resin is 10-20 kg.

[0014] In one embodiment, the electrolyte is selected from an anionic electrolyte containing sulfate ions, citrate ions, tartrate ions, or a cationic electrolyte containing alkali metal ions or alkaline earth metal ions.

[0015] In one embodiment, relative to 10 kg of kerosene used to prepare the base ink, the amount of water is 150-200 kg, the amount of glycerol is 15-40 kg, the amount of electrolyte is 1-5 kg, and the amount of preservative is 300-600 g;

[0016] Preferably, relative to 10 kg of kerosene used to prepare the base ink, the amount of water is 160-180 kg, the amount of glycerol is 20-30 kg, the amount of electrolyte is 2.5-4 kg, and the amount of preservative is 400-450 g.

[0017] In one embodiment, the amount of kerosene used to prepare the oil phase is 0-5 kg ​​relative to 10 kg of kerosene used to prepare the base ink.

[0018] In one embodiment, the electrical conductivity of the water is less than 10 us / cm.

[0019] In one embodiment, the mixing and dispersing is carried out at a temperature of 50-60°C and for a time of 120-140 minutes;

[0020] The emulsification temperature is 50-60° C. and the emulsification time is 40-50 min.

[0021] The second technical solution provided by the present invention is as follows:

[0022] The water-based high-precision ink for an integrated quick-printing machine is prepared according to the preparation method described above.

[0023] Based on the above, the water-based high-precision ink of the integrated quick printing machine provided by the present invention has high printing clarity, low ink consumption, good back staining and high stability.

[0024] Other features and beneficial effects of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other beneficial effects of the present invention can be achieved and obtained by the structures specifically pointed out in the description and claims. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments; the technical features designed in the different implementation modes of the present invention described below can be combined with each other as long as they do not conflict with each other; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that all terms used in the present invention (including technical terms and scientific terms) have the same meanings as those generally understood by ordinary technicians in the field to which the present invention belongs, and cannot be understood as limiting the present invention; it should be further understood that the terms used in the present invention should be understood to have the same meanings as these terms in the context of this specification and in the relevant fields, and should not be understood in an idealized or overly formal sense, unless explicitly defined in the present invention.

[0027] The embodiment of the present invention provides a method for preparing a water-based high-precision ink for an integrated quick-printing machine, the method comprising:

[0028] (1) obtaining an oil phase, wherein the oil phase is obtained by mixing a qualified base ink with kerosene;

[0029] The preparation of the qualified base ink comprises mixing, dispersing and grinding machine oil, kerosene, emulsifier, resin and pigment in sequence, so that the fineness of the obtained base ink reaches 5 to 10 μm, and then the base ink is sealed and stored to obtain the qualified base ink;

[0030] In an embodiment of the present invention, obtaining the oil phase includes pre-dispersion and grinding;

[0031] The pre-dispersion includes weighing machine oil, kerosene, emulsifier, resin and pigment in sequence and adding them into a mixer to mix and stir evenly, and the mixing and dispersing temperature is 50-60°C and the time is 120-140 minutes; preferably, the pre-dispersed added raw materials are added in the manner of liquid materials first, and solid materials and pigments are added later, so that the pigment is better dispersed in the liquid material during the process of adding and stirring; preferably, the mixer for stirring is a double-layer structure, and oil or water is used as the medium for electrical heating;

[0032] The grinding includes pumping the mixed and stirred pigment-containing pre-dispersed liquid into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The base ink obtained after grinding reaches a fineness of 5 to 10 μm, and then the base ink is pumped into an ink storage tank for sealed storage; the sealed storage can be stored at normal ambient temperature, and the storage time is generally not more than one month to observe the stability of the base ink; the present invention does not specifically limit the grinding conditions, for example, it can be sand grinding, etc. In addition, the grinding conditions can be as long as the fineness of the obtained base ink reaches 5 to 10 μm, usually including a temperature of 30-50°C and a grinding number of 2-5 times.

[0033] As the machine oil suitable for the present invention, the machine oil can be: a lubricating oil obtained by dewaxing, solvent refining and white clay treatment of petroleum lubricating oil fractions, and is graded according to the kinematic viscosity at 40°C. Various existing machine oils are suitable for preparing the water-based high-precision ink of the integrated quick printing machine; in a preferred embodiment, the kinematic viscosity of the machine oil at 40°C is 30-80 mm 2 / s, the kinematic viscosity of the machine oil at 40°C can be 30, 40, 50, 60, 70, 80 mm 2 / s, etc., or any point value between the above two;

[0034] As the emulsifier suitable for use in the present invention, the emulsifier may be: benzylphenol polyoxyethylene ether, alkylphenol polyoxyethylene ether, phenethylphenol polyoxyethylene ether and oleic acid polyoxyethylene ester, etc. The above emulsifiers may be added individually or in a mixed form of two or more.

[0035] As the resin suitable for use in the present invention, the resin may be: rosin; rosin-based resins such as polymerized rosin, hydrogenated rosin, rosin resin, hydrogenated rosin resin, etc.; rosin-modified resins such as rosin polyester resin, rosin-modified alkyd resin, rosin-modified maleic acid resin, rosin-modified phenolic resin, etc., and the above resins may be added alone or in a mixture of two or more. In the present invention, the added resin itself has a certain viscosity and will not penetrate into the inside of the paper. Therefore, it can be attached to the surface of the paper to form a layer of ink film, which is quickly dried by oxidation to avoid excessive penetration of ink into the paper during printing, thereby reducing ink consumption and improving printing clarity; and after the addition of the resin, the viscosity of the ink is improved, the structure is tighter, and the stability of the ink is improved; in a preferred embodiment, the molecular weight of the resin is between 10,000 and 100,000; preferably, the molecular weight of the resin is between 30,000 and 50,000. Considering both fixation and printing adaptability, the inventors have found through research that if the molecular weight of the added resin is too low, it is easy to penetrate into the paper, not easy to dry, and easy to get dirty, resulting in higher ink consumption; and if the molecular weight is too high, the fluidity is poor and it is easy to dry, resulting in difficulty in ink transfer and easy clogging after long-term storage.

[0036] More importantly, the present invention adds kerosene in two parts, premixes the machine oil, part of the kerosene, the emulsifier, the resin and the pigment and then grinds them, the obtained base ink is stored in a closed environment, and before emulsification, the other part of the kerosene is premixed with the qualified base ink, thereby further improving the viscosity of the oil phase.

[0037] As pigments suitable for use in the present invention, the pigments may be: carbon black, titanium dioxide; azo pigments, phthalocyanine pigments, nitroso pigments, nitro pigments, vat dye pigments, basic dye pigments, acid dye pigments and natural dye pigments; diazo dyes, anthraquinone dyes and other oil-soluble dyes, etc., and the above pigments may be added individually or in a mixed form of two or more.

[0038] In a preferred embodiment, relative to 10 kg of kerosene used to prepare the base ink, the amount of the pigment is 15 to 30 kg, the amount of the emulsifier is 10 to 20 kg, the amount of the machine oil is 50 to 100 kg, and the amount of the resin is 10 to 20 kg.

[0039] In a preferred embodiment, the amount of kerosene used to prepare the oil phase is 0-5 kg ​​relative to 10 kg of kerosene used to prepare the base ink. In the present invention, kerosene is added to the prepared oil phase in order to adjust the viscosity of the base ink. If the viscosity of the base ink is high, kerosene needs to be added, and if the viscosity of the base ink is low, no kerosene needs to be added.

[0040] (2) obtaining an aqueous phase, wherein the aqueous phase is obtained by mixing water, glycerol, electrolytes, and a preservative;

[0041] The water used in the present invention is not particularly limited as long as it is clean water, and can be appropriately selected depending on the purpose. Examples of the water include tap water, ion-exchanged water, and distilled water.

[0042] In a preferred embodiment, the conductivity of the water is less than 10 us / cm. Controlling the conductivity of the water is beneficial to improving the stability of the ink and extending the shelf life of the ink.

[0043] As a high-precision ink, in an embodiment of the present invention, glycerol is added to the water phase. Since it is directly mixed in the water phase, the glycerol molecules can form hydrogen bonds with water molecules, slowing down the molecular movement of water, thereby avoiding the formation of the same crystal lattice between water molecules, thereby achieving the effect of lowering the freezing point of water, and after the subsequent emulsification of the water phase and the oil phase to form ink, the moisture retention and stability of the ink are improved, thereby improving the printing accuracy and effect of the ink.

[0044] In the present invention, electrolytes are added to the aqueous phase to improve the stability of the emulsion. The electrolyte is selected from anionic electrolytes containing sulfate ions, citrate ions, tartrate ions, or cationic electrolytes containing alkali metal ions or alkaline earth metal ions. As electrolytes suitable for the present invention, preferred ones may be: magnesium sulfate, sodium sulfate, sodium citrate, sodium hydrogen phosphate, sodium borate, sodium acetate, aluminum sulfate, etc. In the present invention, in order to prevent bacteria or mold from breeding in the ink, some preservatives that can be added to the aqueous phase may be added to achieve long-term preservation of the ink. As preservatives suitable for the present invention, sodium benzoate, potassium sorbate, sodium dehydroacetate, calcium propionate, sodium diacetate, sodium lactate, etc. may be used, and the above preservatives may be added individually or in a mixed form of two or more.

[0045] Optionally, other functional additives such as fungicides may be added to the water phase.

[0046] In a preferred embodiment, relative to 10 kg of kerosene used to configure the base ink, the amount of water is 150-200 kg, the amount of glycerol is 15-40 kg, the amount of electrolyte is 1-5 kg, and the amount of preservative is 300-600 g; more preferably, relative to 10 kg of kerosene used to configure the base ink, the amount of water is 160-180 kg, the amount of glycerol is 20-30 kg, the amount of electrolyte is 2.5-4 kg, and the amount of preservative is 400-450 g.

[0047] (3) The water phase and the oil phase are mixed and emulsified.

[0048] Preferably, the emulsification temperature is 50-60° C. Since the resin is added, it is beneficial to achieve sufficient emulsification at a higher temperature, so that the emulsification effect is better. The time is 40-50 minutes.

[0049] The following examples and comparative examples are used to illustrate the present invention in more detail, but are not intended to limit the present invention in any way. In addition, unless otherwise specified, the raw materials used may also be conventional commercial products in the art, or may be prepared by conventional methods in the art.

[0050] The sources of raw materials used in the examples and comparative examples of the present invention are as follows, but are not limited to the following raw materials:

[0051] The kinematic viscosity of the selected mechanical oil at 40°C is 52.5 mm 2 / , the selected pigment is carbon black, the selected emulsifier is polyoxyethylene oleate, the selected resin is rosin-modified phenolic resin, the selected electrolyte is magnesium sulfate, and the selected preservative is sodium benzoate.

[0052] Example 1

[0053] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0054] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (molecular weight of 40,000) and 10kg of carbon black are weighed in sequence and added into a blender for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The blender is a double-layer structure, and water is used as the medium for electrical heating.

[0055] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0056] Step 3, emulsification: 71kg of qualified base ink and 2kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0057] Example 2

[0058] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0059] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (molecular weight 6,000) and 10kg of carbon black are weighed in sequence and added into a mixer for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The mixer is a double-layer structure, and water is used as the medium for electrical heating.

[0060] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0061] Step 3, emulsification: 71kg of qualified base ink and 2kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0062] Example 3

[0063] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0064] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (molecular weight of 150,000) and 10kg of carbon black are weighed in sequence and added into a blender for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The blender is a double-layer structure, and water is used as the medium for electrical heating.

[0065] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0066] Step 3, emulsification: 71kg of qualified base ink and 2kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0067] Example 4

[0068] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0069] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (molecular weight of 20,000) and 10kg of carbon black are weighed in sequence and added into a blender for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The blender is a double-layer structure, and water is used as the medium for electrical heating.

[0070] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0071] Step 3, emulsification: 71kg of qualified base ink and 2kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0072] Example 5

[0073] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0074] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (molecular weight 60,000) and 10kg of carbon black are weighed in sequence and added into a blender for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The blender is a double-layer structure, and water is used as the medium for electrical heating.

[0075] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0076] Step 3, emulsification: 71kg of qualified base ink and 2kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0077] Example 6

[0078] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0079] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (rosin-modified alkyd resin with a molecular weight of 40,000) and 10kg of carbon black are weighed in sequence and added into a mixer for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The mixer is a double-layer structure, and water is used as the medium for electrical heating.

[0080] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0081] Step 3, emulsification: 71kg of qualified base ink and 1kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0082] Example 7

[0083] This embodiment provides a water-based high-precision ink for an integrated quick-printing machine, and a preparation method thereof comprises the following steps:

[0084] Step 1, pre-dispersion: 40kg of machine oil, 5kg of kerosene, 8kg of emulsifier, 8kg of resin (including 4kg of rosin-modified alkyd resin with a molecular weight of 40,000 and 4kg of rosin-modified phenolic resin with a molecular weight of 40,000) and 10kg of carbon black are weighed in sequence and added into a mixer for mixing and stirring to obtain a pre-dispersion liquid, the mixing temperature is 60°C, and the stirring time is 120min. The mixer is a double-layer structure, and water is used as the medium for electrical heating.

[0085] Step 2, grinding: the mixed pigment-containing pre-dispersion liquid is pumped into a sand mill through a diaphragm pump, and the sand mill further grinds and refines the particles in the oil phase. The fineness of the base ink obtained after grinding reaches 8 μm. Then, the base ink is pumped into an ink storage tank, sealed and stored at room temperature for 24 hours, and the stability of the base ink is observed;

[0086] Step 3, emulsification: 71kg of qualified base ink and 1.5kg of kerosene are mixed evenly to obtain an oil phase, and 90kg of water, 15kg of glycerol, 1.5kg of magnesium sulfate, and 200g of preservative are mixed evenly to obtain a water phase, and then the oil phase and the water phase are mixed and emulsified in a vacuum emulsifier to obtain a finished ink; wherein the emulsification temperature is 60°C and the emulsification time is 40min. The vacuum emulsifier is a double-layer structure, and uses water as a medium for electrical heating.

[0087] Comparative Example 1

[0088] The difference between this comparative example and Example 1 is that no resin is added.

[0089] Comparative Example 2

[0090] The difference between this comparative example and Example 1 is that no glycerol is added.

[0091] Comparative Example 3

[0092] The difference between this comparative example and Example 1 is that the emulsification temperature is 35° C. and the emulsification tank is not heated.

[0093] Comparative Example 4

[0094] The difference between this comparative example and Example 1 is that ethylene glycol is used instead of glycerol.

[0095] Comparative Example 5

[0096] The difference between this comparative example and Example 1 is that ethylene glycol is used instead of glycerol and the ethylene glycol is placed in the oil phase for mixing.

[0097] Test Case

[0098] The present invention tests the clarity, ink consumption, back dirtiness, and stability of the inks prepared in Examples 1-7 and Comparative Examples 1-5. The specific test methods are as follows:

[0099] (1) Clarity: After printing 1,000 sheets of ink on a text plate on an all-in-one machine, samples were taken and observed with the naked eye. The clarity was divided into four levels: A, B, C, and D from high to low;

[0100] (2) Ink consumption: The difference is calculated by weighing the ink before and after printing 1,000 sheets of paper on a text plate on an all-in-one machine. The unit is g / sheet. Generally, the lower the ink consumption, the better, as long as it does not affect the printing effect.

[0101] (3) Back dirtiness: 1,000 sheets of ink were printed continuously on the integrated machine using a text plate, and then 20 samples were taken continuously. The ink rubbing on the front and back of the samples was observed with the naked eye. If the front printing was clear and there was no ink rubbing on the back, it meant that the back dirtiness effect was good. The back dirtiness effect was divided into four levels from good to bad: A, B, C, and D.

[0102] (4) Stability: 80 g of sample ink was taken out of a glass bottle and placed in a 60°C constant temperature box and a -20°C freezer for two days respectively. The viscosity change was measured. The smaller the viscosity change, the better the stability.

[0103] The experimental results are shown in Table 1:

[0104] Table 1

[0105]

[0106]

[0107] According to the above table, it can be seen from Examples 1-5 that the lower the molecular weight of the selected resin, the worse the back dirty effect; if the molecular weight of the selected resin is too low or too high, it will affect the clarity and stability of the ink when it is continuously printed on the text plate on the all-in-one machine; the higher the molecular weight of the selected resin, the smaller the ink consumption; from the two aspects of fixation and printing adaptability, it was found that the selected resin molecular weight is between 30,000 and 50,000, the effect is best, and can meet the use requirements of high-precision ink.

[0108] According to the comparison between Example 1 and Comparative Example 1, the ink provided in Comparative Example 1 without adding resin is not as good as that in Example 1 with adding resin in terms of clarity, ink consumption, back dirtiness or stability;

[0109] According to the comparison between Example 1 and Comparative Example 2, it can be seen that the ink provided in Comparative Example 2 does not contain glycerol, resulting in poor stability, short shelf life and easy water leakage of the ink.

[0110] According to the comparison between Example 1 and Comparative Example 3, when the emulsification temperature is low, the stability of the ink obtained will be worse and the ink will be more likely to leak water.

[0111] According to the comparison between Example 1 and Comparative Example 4, it can be seen that the ink obtained by using ethylene glycol instead of glycerol and mixing ethylene glycol in the oil phase is less stable than the ink obtained by using glycerol in the water phase.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a water-based high-precision ink for an integrated quick-printing machine, characterized in that: The method comprises: Obtaining an oil phase, wherein the oil phase is obtained by mixing a qualified base ink with kerosene; The preparation of the qualified base ink comprises mixing, dispersing and grinding machine oil, kerosene, emulsifier, resin and pigment in sequence, so that the fineness of the obtained base ink reaches 5 to 10 μm, and then the base ink is sealed and stored to obtain the qualified base ink; obtaining an aqueous phase, wherein the aqueous phase is obtained by mixing water, glycerin, electrolytes and preservatives; The water phase and the oil phase are mixed and emulsified.

2. The preparation method according to claim 1, characterized in that: The resin is selected from any one of rosin resin, rosin modified resin, phenolic resin, petroleum resin or a mixture thereof.

3. The preparation method according to claim 1 or 2, characterized in that: The molecular weight of the resin is between 10,000 and 100,000; preferably, the molecular weight of the resin is between 30,000 and 50,000.

4. The preparation method according to claim 1, characterized in that: With respect to 10 kg of kerosene used to prepare the base ink, the amount of the pigment is 15 to 30 kg, the amount of the emulsifier is 10 to 20 kg, the amount of the machine oil is 50 to 100 kg, and the amount of the resin is 10 to 20 kg.

5. The preparation method according to claim 1, characterized in that: The electrolyte is selected from an anionic electrolyte containing sulfate ions, citrate ions, tartrate ions, or a cationic electrolyte containing alkali metal ions or alkaline earth metal ions.

6. The preparation method according to claim 1, characterized in that: With respect to 10 kg of kerosene used to prepare the base ink, the amount of water is 150-200 kg, the amount of glycerol is 15-40 kg, the amount of electrolyte is 1-5 kg, and the amount of preservative is 300-600 g; Preferably, relative to 10 kg of kerosene used to prepare the base ink, the amount of water is 160-180 kg, the amount of glycerol is 20-30 kg, the amount of electrolyte is 2.5-4 kg, and the amount of preservative is 400-450 g.

7. The preparation method according to claim 1, characterized in that: The amount of kerosene used to prepare the oil phase is 0 to 5 kg relative to 10 kg of kerosene used to prepare the base ink.

8. The preparation method according to claim 1, characterized in that: The electrical conductivity of the water is less than 10 us / cm.

9. The preparation method according to claim 1, characterized in that: The mixing and dispersing temperature is 50-60°C and the time is 120-140°C; The emulsification temperature is 50-60° C. and the emulsification time is 40-50 min.

10. A water-based high-precision ink for an integrated quick-printing machine obtained by the preparation method according to any one of claims 1 to 9.

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