KR102379912B1 - Resin coating method - Google Patents

Abstract

The present invention relates to a method for coating a resin with a fast curing rate. The present invention relates to the steps of filling a first container with a resin monomer, filling a second container with a curing agent for the resin, adding the compound filled in each of the first and second containers to a static mixer, and the static It provides a method for coating a thermosetting resin, comprising the step of applying a mixture mixed in a mixer to the object to be coated, wherein the mixture of the resin and the curing agent is applied within a preset time after being put into the static mixer. According to the present invention, since starting the curing reaction of the resin and applying the resin are performed at the same time, sufficient time can be secured from the time the resin starts to harden until the resin is evenly applied on the object to be coated. . Therefore, according to the present invention, even a resin having a fast curing rate can be coated uniformly.

Description

Resin coating method {RESIN COATING METHOD}

The present invention relates to a method for coating a resin with a fast curing rate.

There are three typical coating processes using resins, slot die coating, roll-to-roll coating, and comma coating. In order to apply the resin in this process, it is necessary to mix the resin in advance in addition to the coating process, and apply the stored resin compound at once or apply it slowly.

However, in this mixing and application method, in the case of a rapidly curing resin, the viscosity increases to 1000 cps or more within a few minutes after mixing, and since it cures rapidly over time, it is not evenly applied to the coater, and the quality of the coating is also It is not suitable because it is not uniform and cannot be controlled.

For example, referring to FIG. 1 , slot die coating is a method of applying a resin to a coater through a plurality of micro-holes. If the curing speed of the resin is fast, a problem of clogging the micro-holes may occur.

For another example, referring to FIG. 2 , comma coating is a method of applying the slurry by passing the slurry between two rolls. The disadvantage is that it cannot be applied evenly.

Conventionally, in order to improve the physical properties of a material, resins of various compositions have been developed. There may be a difference in curing speed depending on the composition of the resin. Due to the above problems, when the curing rate of the resin is fast, there is a problem in that it is difficult to apply the resin to the product.

An object of the present invention is to provide a coating method capable of uniformly coating an object to be coated with a resin having a fast curing rate in order to solve the above problem.

Specifically, an object of the present invention is to provide a coating method capable of uniformly coating a resin having a fast curing rate on a film in coating a thermosetting resin on a film using a roll coating method.

Another object of the present invention is to provide a coating method capable of uniformly coating an epoxy resin having a fast curing rate on a film.

In addition, an object of the present invention is to provide a coating method capable of uniformly coating a urethane resin having a fast curing rate thereon.

In order to achieve the above object, the present invention is applied by mixing a resin and a curing agent immediately before coating.

In a specific embodiment, the present invention comprises the steps of filling the resin monomer in the first container, filling the second container with a curing agent for the resin, and injecting the compound filled in each of the first and second containers into a static mixer and applying the mixture mixed in the static mixer to the object to be coated, wherein the mixture of the resin and the curing agent is applied within a preset time after being put into the static mixer Coating of a thermosetting resin provide a way

In an embodiment, the method may further include measuring a refractive index of the mixture mixed in the static mixer.

In one embodiment, the resin may be a mixture of an epoxy resin and a thiol compound.

In an embodiment, the curing agent is phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, glutaric anhydride , may include at least one of methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hydrogenated methylnadic anhydride, and hydrogenated nadic anhydride.

In an embodiment, a reaction catalyst may be added to any one of the first and second containers.

In an embodiment, the resin may be a mixture of the first and second thiol compounds.

In one embodiment, the curing agent may be an isocyanate compound.

In an embodiment, a reaction initiator may be added to any one of the first and second containers.

According to the present invention, since starting the curing reaction of the resin and applying the resin are performed at the same time, sufficient time can be secured from the time the resin starts to harden until the resin is evenly applied on the object to be coated. . Therefore, according to the present invention, even a resin having a fast curing rate can be coated uniformly.

1 is a conceptual diagram illustrating a slot die coating method.
2 is a conceptual diagram illustrating a comma coating method.
3 and 4 are conceptual views illustrating a roll coating method according to the present invention.
5 is a flowchart showing a coating method according to the present invention.
6 is a conceptual diagram illustrating an injection device according to the present invention.
7 is a conceptual diagram illustrating a static mixer according to the present invention.
8 is a flowchart illustrating a coating method including a step of measuring the refractive index of a resin.
9 is a conceptual diagram illustrating a method for measuring a refractive index of a resin.
10 is a graph showing the refractive index according to the composition of the resin.

Hereinafter, the embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but the same or similar components are assigned the same reference numbers regardless of reference numerals, and redundant description thereof will be omitted. In addition, in describing the embodiments disclosed in the present specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in this specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed herein is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present invention , should be understood to include equivalents or substitutes.

Terms including an ordinal number such as 1st, 2nd, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as “comprises” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

The present invention is an invention for uniformly coating an object to be coated before a thermosetting resin is cured. Before describing the coating method according to the present invention, the curing reaction of the resin will be described.

When the resin monomer and the curing agent are mixed, curing proceeds through a polymerization reaction. That is, as a polymer is formed through a polymerization reaction between the resin monomer and the curing agent, the curing reaction proceeds.

Meanwhile, in the curing reaction, a catalyst for accelerating the curing reaction, an initiator used to initiate a chain reaction, an additive that does not participate in the reaction, and the like, which affects the physical properties of the resin, may be added.

The rate of the curing reaction may vary depending on the reactivity of the resin monomer and the curing agent, and the presence or absence of an initiator or additive. When the curing reaction of the resin proceeds, the viscosity of the resin increases gradually. The faster the curing reaction rate, the faster the viscosity increase rate.

1 and 2, when the viscosity of the resin rapidly increases, it becomes difficult to evenly apply the resin to the object to be coated. The present invention provides a coating method for solving the above-mentioned problems.

Before describing the coating method according to the present invention, a general thermosetting resin coating will be described. In the present specification, a roll coating method of forming a thermosetting resin layer between two sheets of film will be described.

3 and 4 are conceptual views illustrating a roll coating method according to the present invention.

Referring to FIG. 3 , the roll coating method may be performed by a resin spraying device 310 , a plurality of rolls 330a , 330b , 340a and 340b , and two sheets of films 330a and 330b .

Specifically, the resin spraying device 310 sprays a resin mixture in which a resin monomer, a curing agent, and an additive are mixed to the object to be coated. At this time, the resin spraying device 310 may apply a resin mixture while moving in various movements according to the shape of the object to be coated. For example, referring to FIG. 4 , when the resin mixture is applied to the film 330a using the resin spraying device 310, the resin spraying device 310 reciprocates in a direction perpendicular to the moving direction of the film 330a. By allowing movement, the resin mixture can be applied in a zigzag pattern.

The roll 320a located below the resin spraying device 310 moves the first film 330a in a predetermined direction. The resin spraying device 310 sprays the resin mixture on the first film 330a moving by the first roll 320a.

On the other hand, the roll 320b located above the first film 330a moves the second film 330b over the first film 330a to which the resin mixture is applied. As the second film 330b moves over the first film 330a, the first film 330a, the resin mixture, and the second film 330b are stacked in this order. Thereafter, the first film 330a, the resin mixture, and the second film 330b are strongly compressed while passing through the two rolls 340a and 340b, and the resin mixture is applied to the first film 330a and the second film 330b. spread evenly between

The coating method according to the present invention may be utilized in the coating method described with reference to FIGS. 3 and 4 . Although the application examples in which the coating method according to the present invention is applied to the coating method described in FIGS. 3 and 4 will be described, it is not limited thereto, and the coating method according to the present invention is applied to all coating methods in which a static mixer to be described later can be utilized. can be

Hereinafter, the coating method according to the present invention will be described in detail.

5 is a flowchart showing a coating method according to the present invention.

First, in the coating method according to the present invention, the first container is filled with a resin monomer (S510) and the second container is filled with a curing agent (S520).

The first container may be filled with a resin monomer for polymerization. Here, the resin monomer may include one type of monomer or a plurality of different types of monomers. The types of resin monomers that can be filled in the first container will be described later.

Meanwhile, other compounds used for curing the resin as well as the resin monomer may be added to the first container. However, compounds that may cause the resin monomer to polymerize should not be added to the first container.

Meanwhile, the second container may be filled with a curing agent for polymerization. Here, the curing agent may include one type of compound or a plurality of different types of compounds. The type of curing agent that can be filled in the second container will be described later.

Meanwhile, in the second container, other compounds used for curing the resin as well as a curing agent may be added. However, compounds that can cause a chemical reaction with the curing agent simply by being mixed with the curing agent should not be added to the second container.

The first and second containers are not necessarily divided into two independent containers, and the compounds filled in each of the first and second containers may not be mixed with each other. As described above, when each of the resin monomer and the curing agent are filled in separate containers, the curing reaction does not occur.

Next, a step (S530) of mixing the compounds filled in each of the first and second containers in a static mixer is performed.

In the coating method described with reference to FIGS. 3 and 4 , the resin spraying device 310 may be replaced with a static mixer. Referring to FIG. 6 , the compounds filled in each of the first container 610 and the second container 620 may be mixed in a static mixer 630 .

The static mixer 630 is a device for mixing and simultaneously injecting two or more types of compounds. Specifically, the static mixer used in the present invention is in the form of a screw, and can mix two or more types of solutions and spray them at the same time. In addition, the ejection amount can be controlled by designating the resin ejection rate as a desired rate in the static mixer during the process. In addition, by adjusting the distance between the static mixer and the object to be coated, it is possible to control the thickness of the coating. In addition, the motion of the static mixer can be modified according to the shape of the object.

For example, referring to FIG. 7 , the static mixer 630 receives compounds from two or more different containers, and then mixes them inside the static mixer 630 . Then, the mixed compounds are sprayed to the outside.

Since the supply of the compound, the mixing of the compound, and the injection of the compound are performed together in the static mixer, in order for the mixture of a certain composition to be injected from the static mixer, the compound supply rate of each of the first and second containers to the static mixer must be constant. do. Furthermore, the composition of the mixture sprayed from the static mixer may be adjusted by adjusting the feed rate.

For example, the resin monomer filled in the first container and the curing agent filled in the second container are each 80 wt. % and 20 wt. %, the ratio of the compound feed rate (mass of compound supplied per unit time) of each of the first and second containers to the static mixer should be 8:2.

On the other hand, when the resin monomer and the curing agent are mixed in the static mixer, the curing reaction starts. Therefore, when the compounds filled in the first and second containers are mixed in the static mixer, they must be coated on the object to be coated within a preset time.

Finally, a step (S540) of applying a mixture of compounds filled in each of the first and second containers to the object to be coated is performed.

As in the method described with reference to FIG. 4 , the static mixer 630 may reciprocate in a direction perpendicular to the moving direction of the first film 330a and spray the resin mixture.

As the first film 330a moves perpendicular to the moving direction of the static mixer, a resin mixture is applied on the first film 330a in a zigzag form. Since the resin and the curing agent are applied on the first film 330a immediately after mixing, the applied resin mixture is in a state in which the curing reaction has not proceeded.

When the second film 330b is covered and compressed on the resin mixture in a state where the curing reaction does not proceed, the resin mixture is evenly spread between the first and second films 330a and 330b. At this time, as described with reference to FIG. 3 , the first and second films may be compressed using the pressing rolls 340a and 340b.

Here, when a resin having a very fast curing rate is coated, a large number of bubbles may be generated between the first and second films 330a and 330b due to a rapid increase in viscosity even when the static mixer 630 is used. To prevent this, it is preferable to compress the first and second films 330a and 330b using two or more pressing rolls.

As described above, the present invention allows the resin mixture to be evenly applied to the object to be coated even if the curing reaction of the resin proceeds quickly by filling the compounds causing the polymerization reaction in different containers and mixing them before application.

Hereinafter, compounds that can be filled in the first and second containers will be described.

First, when it is desired to coat an epoxy resin having a fast curing reaction, the compound filled in the first and second containers will be described.

The first container may be filled with an epoxy compound. For example, in the first container, there may be bisphenol types such as bisphenol A type, bisphenol F type, bisphenol S type and their hydrogenated products, and may be a novolak type such as phenol novolak type or cresol novolak type, triglyceride It may be a nitrogen-containing cyclic type such as a cydyl isocyanurate type or a hydantoin type. In addition, the first container may be filled with an aromatic type such as an alicyclic type, an aliphatic type, and a naphthalene type, a low absorption rate type such as a glycidyl ether type or a biphenyl type, and a dicyclo type such as a dicyclopentadiene type. In addition, the first container may be filled with an ester type, an ether ester type and a modified type thereof. However, the present invention is not limited thereto.

Meanwhile, a thiol compound may be added to the first container together. The thiol compound may be used for increasing the refractive index of the epoxy resin.

Here, the thiol compound is 2,3-bis(2-mercaptoethylthio)propane-1-thiol, 2-(2-mercaptoethylthio)-3-2-[3-mercapto-2(2-mer Captoethylthio)-propylthio]-ethylthio-propane-1-thiol, 2-(2-mercaptoethylthio)propane-1,3-dithiol and 4-mercaptomethyl-3,6-dithiol- It may be at least one of 1,8-octane dithiol, but is not limited thereto.

Meanwhile, when the epoxy compound is added to the first container, an acid anhydride curing agent may be added to the second container. For example, in the second container, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, glutaric anhydride, At least one of methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hydrogenated methylnadic anhydride and hydrogenated nadic anhydride may be added.

Meanwhile, each of the catalyst and the dye added to the epoxy resin may be added to any one of the first and second containers.

Next, when it is desired to coat thiourethane having a fast curing reaction, the compound filled in the first and second containers will be described.

At least one type of thiol compound may be added to the first container. For example, in the first container, 2,3-bis(2-mercaptoethylthio)propane-1-thiol, 2-(2-mercaptoethylthio)-3-2-[3-mercapto-2 (2-mercaptoethylthio)-propylthio]-ethylthio-propane-1-thiol, 2-(2-mercaptoethylthio)propane-1,3-dithiol and 4-mercaptomethyl-3,6 At least one of -dithiol-1,8-octanedithiol may be added. However, the present invention is not limited thereto.

When the thiol compound is filled in the first container, the isocyanate compound may be filled in the second container. For example, the second container may be filled with at least one of isopron diisocyanate, 1,6-hexamethylene disocyanate, and cyclohexylmethane diisocyanate (H12MDI). However, the present invention is not limited thereto.

Meanwhile, each of the ultraviolet absorber, the release agent, the initiator and the dye added to the thiourethane resin may be added to any one of the first and second containers.

In the above, the compounds that can be filled in the first and second containers have been described.

Hereinafter, a method for detecting the composition of the resin mixture applied to the coating target object will be described.

When the composition of the resin mixture applied to the object to be coated is changed, the physical properties of the resin are changed. Therefore, the composition of the resin mixture applied to the object to be coated must always be constant.

However, the composition of the compound injected from the static mixer may vary depending on various external factors. For example, the external factor may be at least one of a case in which the compound feed rate to the static mixer is not completely controlled and a case in which the compounds are not completely mixed in the static mixer, but is not limited thereto. The composition of the sprayed compound may vary.

In order to solve the above problem, the present invention detects the composition of the resin mixture sprayed from the static mixer in real time, so that the coating target object can be coated with the resin mixture of a certain composition. Hereinafter, a coating method including the step of detecting the composition of the resin mixture applied to the coating object will be described.

8 is a flowchart illustrating a coating method including detecting a composition of a resin mixture applied to a coating target object.

First, in the coating method according to the present invention, the first container is filled with a resin monomer (S810) and the second container is filled with a curing agent (S820). Next, a step (S830) of mixing the compound filled in each of the first and second containers in a static mixer is performed. Since S810 to S830 are the same as S510 to S530 described in FIG. 5, a detailed description thereof will be omitted. .

Next, the step of measuring the refractive index of the mixture mixed in the static mixer (S840) proceeds.

The refractive index of the resin mixture depends on its composition. In addition, the refractive index of a resin mixture having the same composition is always measured as the same value. Therefore, by measuring the refractive index of the resin mixture injected from the static mixer, it can be confirmed whether the composition of the resin mixture is the same as the target composition.

On the other hand, since the refractive index may change as the curing reaction proceeds in the resin mixture, it is preferable to measure the refractive index of the resin mixture immediately after the resin monomer and the curing agent are completely mixed.

For example, referring to FIG. 9 , when measuring the refractive index of the resin mixture immediately after being sprayed from the injection hole of the static mixer, the refractive index immediately after mixing the resin monomer and the curing agent may be measured.

When the refractive index of the resin mixture injected from the injection port of the static mixer is equal to the preset refractive index, the resin mixture is continuously applied to the first film 330a ( S860 ). However, when the refractive index of the resin mixture injected from the fountain of the static mixer is different from the preset refractive index, the coating process may be stopped ( S870 ).

As described above, the present invention measures the refractive index of the resin mixture sprayed from the static mixer, so that the resin mixture having a desired composition can be applied to the object to be coated.

Hereinafter, the refractive index measurement results according to the composition of the resin mixture will be described.

Based on the total mass of the resin mixture, the content of the curing agent was 22.5 wt. %, the results of measuring the refractive index immediately after mixing the resin monomer (A) and the curing agent (B) are shown in Table 1 below.

number of measurements 1 time Episode 2 3rd time 4 times 5 times Episode 6 refractive index of the ejected mixture 1.5212 1.5212 1.5212 1.5213 1.5212 1.5212

Referring to the results of Table 1, it can be confirmed that the refractive index of the resin mixture having the same composition is always measured as the same value.

Meanwhile, the refractive index of the resin mixture was measured by varying the ratio of the curing agent in the resin mixture. The measurement results are shown in FIG. 10 . Referring to FIG. 10 , it can be seen that the refractive index varies according to the composition of the resin mixture.

Combining the results of Table 1 and FIG. 10 , by measuring the refractive index of the resin mixture injected from the static mixer, it can be determined whether the composition of the resin mixture matches the target composition.

As described above, according to the present invention, since starting the curing reaction of the resin and applying the resin are performed at the same time, sufficient time is required from the time the resin starts to cure until the resin is evenly applied on the body to be coated. can be obtained Therefore, according to the present invention, uniform coating is possible even for a resin having a fast curing rate.

It is apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention.

In addition, the above detailed description should not be construed as limiting in all respects, but should be considered as exemplary. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (8)

In the coating method of a thermosetting resin using a roll coating method,
filling the first container with a resin monomer;
filling a second container with a curing agent for the resin;
adding the compound filled in each of the first and second containers to a static mixer; and
As comprising the step of applying the mixture mixed in the static mixer to the object to be coated,
Further comprising the step of measuring the refractive index of the mixed mixture in the static mixer,
Measuring the refractive index is measured immediately after the resin monomer and the curing agent are completely mixed,
A method of coating a thermosetting resin. delete According to claim 1,
The resin is a coating method of a thermosetting resin, characterized in that a mixture of an epoxy resin and a thiol compound. 4. The method of claim 3,
The curing agent,
Phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, glutaric anhydride, methylhexahydrophthalic anhydride, methyltetrahydro A method for coating a thermosetting resin comprising at least one of phthalic anhydride, hydrogenated methyl nadic anhydride, and hydrogenated nadic anhydride. 5. The method of claim 4,
A method for coating a thermosetting resin, characterized in that a reaction catalyst is added to any one of the first and second containers. According to claim 1,
The resin is a coating method of a thermosetting resin, characterized in that the mixture of the first and second thiol compounds. 7. The method of claim 6,
The curing agent is a method for coating a thermosetting resin, characterized in that the isocyanate compound. 8. The method of claim 7,
A method for coating a thermosetting resin, characterized in that an initiator for initiating a chain reaction is added to any one of the first and second containers.

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