KR100341140B1 - Resin-reinforced emulsion resin for hydrophilic ink and method of making the same - Google Patents

Abstract

The present invention relates to a resin-reinforced emulsion resin for water-based ink and a method for manufacturing the same, and more particularly, to prepare an ink without using a thickener or anionic emulsifier by providing a place for emulsification by adding a water-soluble resin before the start of the reaction. It relates to a resin having a suitable viscosity and physical properties and to a method for producing the same. The resin prepared according to the present invention has high viscosity and excellent ink properties, has a high acid value range and various glass transition temperatures, and is applicable to various fields.

Description

Resin-reinforced emulsion resin for hydrophilic ink and method of making the same}

The present invention relates to a resin-reinforced emulsion resin for water-based ink and a method for producing the same, and more particularly, to a resin-reinforced emulsion resin produced using a water-soluble resin as an emulsifier and a method for synthesizing thereof.

The water-soluble resin is composed of a hydrophilic part and a hydrophobic part in chemical structure like a general emulsifier. Thus, the properties of emulsifiers, including water soluble resins, are determined by the chemical structure of the hydrophilic and hydrophobic moieties and their proportions. Water-soluble resins are soluble in water due to hydrophilic moieties, but are restricted in their behavior in water due to hydrophobic moieties, which lead to the formation of micelles (micelles) in the water. These micelles are used as reaction sites due to the unique reaction mechanism of emulsion polymerization, and the resultant polymer is in the form of round particles. Thus, the water-soluble resin used in the polymerization is used as the polymerization site in the emulsion polymerization. In addition, the water-soluble resin imparts structural or electrostatic stability to the polymer particles synthesized due to the hydrophilic portion. In addition, water-soluble resins increase the compatibility of emulsion resins and pigments in end applications such as inks, and because of their number average molecular weight of 500 to 20,000 g / mol, the Newtons in synthesized emulsion resins Gives Newtonian-like flow.

Current printing technology is evolving to a higher speed, but if the emulsion resin used in the ink shows a non-Newtonian flow, the viscosity of the ink during printing is greatly reduced, which is caused by a large amount of ink loss. It leads. Thus, if the emulsion resin used in the ink exhibits Newton-type flowability, it can greatly increase its efficiency in printing.

In addition, in the case of the emulsion resin synthesized using a general emulsifier, its usage is limited by the strong hydrophilicity of the acid monomers, and therefore, the acid value of the synthesized emulsion resin is not easily controlled. However, in the case of Resin Fortified emulsion, resin acid emulsions having an acid value in the range of 25 to 80 can be easily synthesized by adjusting only the acid value and the amount of the water-soluble resin to be used. The ease of adjustment of acid value enables more efficient control of many physical properties such as adhesion of synthetic emulsion resins, compatibility with pigments, water resistance, alcohol resistance, etc., so that it can be applied to a wider range of applications. very important.

In Korean Patent Publication No. 99-075204, a nonionic emulsifier was added at a time before the start of the polymerization reaction, and then a monomer was continuously added to the reactor to synthesize a resin polypeptide emulsion resin having a solid content of 50%. The acid value of the water-soluble resin used at this time is 130-200, and the quantity used has the range of 18-24 weight% on a monomer basis. The final acid value of the resin-reinforced emulsion resin thus polymerized has a range of about 25-50. The reaction temperature was 80 ° C., and the monomer composition used was fixed at styrene (40%) / methyl methacrylate (31%) / 2-ethylhexyl acrylate (29%). Thus, the glass transition temperature of the finally synthesized polymer was used. Figure 40 shows a constant value. The final viscosity of the resin polymerized emulsion resin thus polymerized represents 100 cps. However, in the ink formulation, the preferred viscosity range is 800 to 2,000 cps, and in order to use the emulsion resin of the present invention as an ink, there is a disadvantage that a separate thickener must be used.

In addition, in U.S. Patent Nos. 4,820,762 and 4,839,413, the reaction temperature was 80 ° C, and the monomers used in the reaction were added semi-continuously, and the feeding time thereof was changed to 0.5 to 2 hours. In the present invention, the water-soluble resin is added semi-continuously during the reaction, but for this reason, a large amount of nonionic and ionic emulsifiers are separately used for providing a reaction site for polymerization and stability of the resulting polymer particles before adding the water-soluble resin. It became. On the monomer basis, 1 to 8% by weight of the nonionic emulsifier and 0.7 to 7.5% by weight of the anionic emulsifier were used for the reaction. However, when the ionic emulsifier is used, there is a disadvantage of deteriorating ink properties.

In order to solve this problem, the present inventors conducted extensive research, and in the method of preparing a resin-reinforced emulsion resin using a water-soluble resin, a reaction site where polymerization can occur in an emulsion polymerization by adding a water-soluble resin before the reaction is initiated. If the nonionic emulsifier is mixed with the monomer and continuously added, the viscosity of the emulsion can be adjusted to about 1000 cps, which is suitable for ink formulation, without using a thickener or ionic emulsifier, and the acid value of the water-soluble resin It was found that by adjusting the amount of use, a resin having a high range of acid values can be obtained, and by adjusting the components and amount of monomers, a resin having various ranges of glass transition temperatures can be synthesized, and the present invention has been completed based on this. .

Accordingly, it is an object of the present invention to provide a method for producing a resin-reinforced emulsion resin having a high viscosity, a wide range of glass transition temperatures and a high range of acid values, without using a separate thickener or ionic emulsifier.

Another object of the present invention is to provide a resin-reinforced emulsion resin prepared according to the above method.

Method for producing a resin-reinforced emulsion resin of the present invention for achieving the above object is a method for producing a resin-reinforced emulsion resin by reacting styrene and an acrylate monomer, the styrene / acrylic water-soluble resin having an acid value of 210 to 230 on a monomer basis 20 to 35% by weight is added before the start of the reaction, and then the nonionic emulsifier is mixed with the monomers and continuously added to carry out emulsion polymerization.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a resin-reinforced emulsion resin for water-based ink using a water-soluble resin and a method for producing the same, wherein the monomers used in the present invention are styrene and acrylic monomers, acrylic acid, methacrylic acid, ethyl acrylate, and butyl acrylate. One or more selected from the group consisting of latex, butyl acrylate, 2-ethyl hexyl acrylate, ethyl acrylate, hydroxy ethyl acrylate, hydroxy ethyl and eta acrylate, preferably styrene and 2-ethylhexyl Acrylate is mixed and used in a composition of 1: 0 to 0: 1.

Meanwhile, the water-soluble resin used in the present invention is a styrene / acrylic water-soluble resin having an acid value of 210 to 230, for example, selected from the group consisting of styrene, alpha ethyl styrene, and acrylic acid, and the amount thereof is 20 to 35% by weight. Is preferred. If the amount of the water-soluble resin is less than 20% by weight, insufficient acid stability of the produced particles does not impart sufficient ink stability. If the amount of the water-soluble resin exceeds 35% by weight, the water-soluble resin may not be adsorbed to the particles and the water-soluble resin present in the aqueous phase may be produced. Stability may be impaired.

In the present invention, by adding the water-soluble resin before the reaction is initiated to provide a reaction place where the polymerization can occur in the emulsion polymerization, there is no need for a separate emulsifier, in particular an anionic emulsifier and a thickener, For stability, only a small amount of nonionic emulsifier was used to synthesize a resin-reinforced emulsion having a small particle size and a high solid content. The emulsion resin thus synthesized showed better values than the conventional resin synthesized by administering the water-soluble resin together with a nonionic emulsifier in physical properties such as defoaming ability and transfer power.

The nonionic emulsifier used in the present invention is selected from the group consisting of polyethylene oxide and polypropylene oxide. The nonionic emulsifier is mixed with the monomer and continuously introduced into the reactor, wherein the nonionic emulsifier is mixed at 10 to 40 parts by weight with respect to 1000 parts by weight of the monomer, and when the mixing amount is less than 10 parts by weight, The problem of not providing sufficient stability may occur, and if it exceeds 40 parts by weight, problems such as defoaming ability and lowering of transfer force may occur due to excessive emulsifier.

When the nonionic emulsifier and the monomer mixture are introduced into the reactor, it should be added slowly and continuously for 120 to 180 minutes, and the reaction temperature is preferably 60 to 90 ° C.

The viscosity of the final latex prepared according to the above method is in the range of about 800 to 2,000 cps, and the acid value of the final emulsion resin is in the range of 45 to 80. In addition, by changing the composition of the monomer freely, it was possible to synthesize a resin polypeptide emulsion having a glass transition temperature of -50 ~ 100 ℃, it was possible to apply in various fields.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

Examples 1-4

1305 g of deionized water, 357 g of water-soluble resin (Hanhwa Petrochemical, trade name: Soluryl 70), and 81 g of ammonia water (28% solution) were added to the reactor at once, and the temperature of the reactor was increased to 86 ° C. while stirring. When the temperature of the reactor reaches 86 ° C., the water-soluble resin is dissolved in alkaline deionized water by maintaining 86 ° C. for 2 hours. After dissolving, a solution of 1 g of ammonium persulfate dissolved in 3 g of deionized water was added to the reactor at once, followed by stirring at 86 ° C. for 30 minutes. After 30 minutes, a solution in which 5 g of ammonium percellate was dissolved in 16 g of deionized water was added to the reactor at a time, and a monomer mixture consisting of monomers and nonionic emulsifiers was continuously added to the reactor for 120 minutes as shown in Table 1 below. 10 minutes after completion of the addition, a solution of 2 g of ammonium persulfate dissolved in 12 g of deionized water is added to the reactor. The reaction was held at 86 ° C. for 45 minutes and then cooled to terminate the reaction.

Resin Fine Emulsion Prescription and Basic Properties edifice Example 1 Example 2 Example 3 Example 4 Deionized water 1336 1336 1336 1336 Water-soluble resins ¹ 357 357 357 357 ammonia 81 81 81 81 ST ² 1080 720 360 0 2-EHA ³ 0 360 720 1080 Nonionic Emulsifiers ⁴ 22 22 22 22 APS ⁵ 8 8 8 8 Glass transition temperature (℃) 100 30 -16 -50 Solid content (%) 50 50 50 50 Particle size (nm) 78 75 70 70 Viscosity (cps) 900 850 850 850 Acid value 55 53 54 55

1: Soluryl 70, Hanwha Chemical

2: styrene

3: 2-ethyl hexyl acrylate

4: Pluronic L-10 from BASF

5: ammonium persulfate

As can be seen in Table 1, a resin polytide emulsion resin having various glass transition temperatures was prepared while freely changing the ratio of styrene and 2-ethylhexyl acrylate, and properties such as acid value, particle size, and viscosity thereof were obtained. It can be seen that little change.

Comparative Examples 1 and 2

22 g of the nonionic emulsifier was synthesized in the same manner as in Examples 1 and 3 except that the reaction mixture was added to the reactor at the same time as the water-soluble resin before starting the reaction.

Prescriptions and Basic Physical Properties of Resin Folded Emulsion edifice Example 1 Example 3 Comparative Example 1 Comparative Example 2 Deionized water 1336 1336 1336 1336 Water-soluble resins ¹ 357 357 357 357 ammonia 81 81 81 81 Nonionic emulsifier 0 0 22 22 ST ² 1080 360 1080 360 2-EHA ³ 0 720 0 720 Nonionic Emulsifiers ⁴ 22 22 0 0 APS ⁵ 8 8 8 8 Glass transition temperature (℃) 100 -16 100 -16 Solid content (%) 50 50 50 50 Viscosity (cps) 900 850 100 100 Acid value 55 54 54 55

1: Soluryl 70, Hanwha Chemical

2: styrene

3: 2-ethyl hexyl acrylate

4: Pluronic L-10 from BASF

5: ammonium persulfate

As shown in Table 2, the present invention provides a emulsion polymerization site by adding a water-soluble resin prior to the addition of the emulsifier, while the same properties of the glass transition temperature, composition, acid value, etc. of the resin can be the same, greatly changing the viscosity of the final latex Could. Therefore, when the emulsion resin synthesized in the present invention is used in the ink, there is no need to use an additive such as a thickener.

Examples 5-8

1305 g of deionized water, 270 to 580 g of water-soluble resin (20 to 35% based on monomer), and 61 to 132 g of ammonia water (28% solution) were added to the reactor at the same time as shown in Table 3, and the temperature of the reactor was increased to 86 ° C. while stirring. do. When the temperature of the reactor reaches 86 ° C., it is maintained at 86 ° C. for 2 hours to dissolve the water-soluble resin. After dissolution, the solution of 1 g of ammonium persulfate dissolved in 3 g of deionized water was added to the reactor at a time and stirred at 86 ° C. for 30 minutes. After 30 minutes, a solution in which 5 g of ammonium percellate was dissolved in 16 g of deionized water was added to the reactor at a time, and a monomer mixture consisting of monomers and nonionic emulsifiers was continuously added to the reactor for 120 minutes. Ten minutes after the addition, 2 g of ammonium persulfate dissolved in 12 g of deionized water is added to the reactor. The reaction is held at 86 ° C. for 45 minutes and then cooled to complete the reaction.

Resin Fine Emulsion Prescription and Basic Properties edifice Example 5 Example 6 Example 7 Example 8 Deionized water 1336 1336 1336 1336 Water-soluble resins ¹ 270 340 463 580 ammonia 61 81 105 132 ST ² 1080 1080 1080 1080 Nonionic Emulsifiers ³ 22 22 22 22 APS ⁴ 8 8 8 8 Acid value 45 50 63 80 Glass transition temperature (℃) 100 100 100 100 Solid content (%) 50 50 50 50 Particle size (nm) 78 75 73 75 Viscosity (cps) 850 900 900 900

1: Soluryl 70, Hanwha Chemical

2: styrene

3: Pluronic L-10 from BASF

4: ammonium persulfate

As shown in Table 3, when the amount of the water-soluble resin was changed to 270 to 580 g to prepare a resin polypeptide emulsion resin, it was possible to prepare a resin polypeptide emulsion resin having various acid values of 45 to 80.

Comparative Example 3

Anionic emulsifiers (sodium laruryl sulfate) were synthesized in the same manner as in Example 6 except that 2% by weight was further used as the monomer ratio. Ink transfer power and antifoaming capacity of the synthesized resin were measured by the following method.

Ink Transfer Force

The transfer force is a physical property that indicates the extent to which the ink is transferred to the substrate (usually paper) through the roll of the printer, and is determined by the weight ratio of the amount of ink used and the amount of ink transferred to the substrate.

<Vesicle power>

Since the prepared ink is a mixture of various substances, it proceeds with stirring during the prescription, and foaming occurs due to the water-soluble resin and the emulsifier present in the emulsion. The antifoaming capacity indicates the physical properties of no foaming at this time and is measured as follows. That is, the height of the bubbles generated by pouring the prepared ink in a 100ml measuring cylinder is measured by time, and the smaller the measured value, the better the defoaming ability.

Resin Fine Emulsion Prescription and Basic Properties edifice Example 2 Comparative Example 2 Deionized water 1336 1336 Water-soluble resins ¹ 357 357 ammonia 81 81 Sodium Lauryl Sulfate 0 22 ST ² 1080 1080 Nonionic Emulsifiers ³ 22 22 APS ⁴ 8 8 Acid value 50 50 Glass transition temperature (℃) 100 100 Solid content (%) 50 50 Particle size (nm) 75 78 Viscosity (cps) 900 800 Ink transfer force 10% improvement Standard Vesicular capacity (mm) Early 20 25 30 seconds 15 18 1 minute 10 12 1 minute 30 seconds 8 10 5 minutes 4 6

1: Soluryl 70, Hanwha Chemical

2: styrene

3: Pluronic L-10 from BASF

4: ammonium persulfate

As shown in Table 4, when the present invention and the anionic emulsifier is used, the particle size, solid content and storage properties are the same, but the present invention shows that the transfer force and antifoaming ability are greatly increased in the evaluation of ink properties. This can be done with the effect of not using an anionic emulsifier.

As discussed above, the viscosity of the resin polytide emulsion resin prepared by the conventional method is too low for ink applications, and an additive such as a thickener should be used, and an anionic emulsifier may be used for the stability of the particles and the role as a reaction site. Although separately used in the present invention, the viscosity of the latex can be adjusted to the viscosity usable in the ink by changing only the method of injecting the nonionic emulsifier. It is not necessary to use an anionic emulsifier that serves to reduce the ability and the transfer power, it is possible to manufacture the ink of the desired physical properties.

Claims (5)

In the method for producing a resin-reinforced emulsion resin by reacting styrene and an acrylate monomer, a non-ionic emulsifier is introduced after 20 to 35% by weight of styrene / acrylic water-soluble resin having an acid value of 210 to 230, based on monomers, before the reaction is started. Is mixed with a monomer and continuously added to emulsion polymerization to produce a resin-reinforced emulsion resin. The method of claim 1 wherein the water soluble resin is selected from the group consisting of styrene, alphamethyl styrene and acrylic acid. The method of claim 1, wherein the monomer is used by mixing styrene / 2-ethylhexyl acrylate in a composition of 1: 0 to 0: 1. The method of claim 1, wherein the nonionic emulsifier is selected from the group consisting of polyethylene oxide and polypropylene oxide, characterized in that used in a mixture of 10 to 40 parts by weight based on 1000 parts by weight of the monomer. It is manufactured by the method of any one of Claims 1-4, It has a glass transition temperature of -50-100 degreeC, an acid value of 45-80, and a viscosity of 800-2,000. Resin reinforced emulsion resin to be used.