KR100880359B1 - Apparatus and method for coating of matrix net using metering roller - Google Patents

Abstract

An apparatus for coating the networked fabric, and a method for coating the networked fabric are provided to reduce the using amount of a volatile organic solvent and to improve productivity. An apparatus for coating the networked fabric for coating a functional coating solution to the networked raw fabric comprises an unwinding part which supplies the networked fabric(110); a liquid film removing roller(220) for uniform dipping; a metering roller(270); a deposition control roller(230); a drying tower which dries and cures the dipped fabric; a heating upper roller; a fabric transfer roller which transfers the coated fabric; and a winding unit.

Description

Apparatus and Method for coating of Matrix Net using metering roller}

The present invention relates to a coating method and a coating apparatus for a net fabric impregnated with a functional coating solution to the net fabric, the coating method of the net fabric, characterized in that to maintain a uniform impregnation and a net structure frame even to the sticky viscosity on the net fabric It relates to a coating device.

The following contents are to be cited in the application No. 10-2007-0077868 filed by the applicant.

Conventional coating processing is based on woven fabrics and non-woven fabrics, the coating process of a polymer material on the surface of the coating process is called coating processing, the type and use is very wide.

Natural processing rubber solution, latex, etc. are coated on the fabric and vulcanized and used as various waterproofing materials. Oil paint is coated, dried and cured on the fabric and used for various purposes. Nylon is industrialized and various synthetic fibers are developed. As a result, various synthetic resins for coating have been developed, but the main ones are PVC coating processing and polyurethane coating processing.

Coating processing methods are generally classified into direct coating method, transfer method, and wet method.

First, the direct coating method is used as a tarpaulin by directly applying a polymer material to the fiber, and in recent years, two kinds of coatings of thermoplastic acrylic resins and more advanced urethane coating process. Most of the purpose of the processing is waterproof, besides, there are tactile control, gloss improvement and torsion prevention. As the most important part of coating processing, the most commonly used type is a roll on coater (knife roll coater) with a doctor knife on the roll, and the fabric is passed through the fabric and the resin is applied. Top and bottom rollers are rotated in opposite directions to each other, and the resin is applied by the rollers rotating in the opposite direction to the direction of the fabric, and the method of coating by attaching a knife to the fabric. The application amount is adjusted by doctor thickness, tension, resin concentration and viscosity.

There is a problem in applying any one of the three methods to the net fabric coating process. When the type of net is passed between the rollers that do not have elongation, such as glass fiber, and the upper and lower contact rollers, there is a problem that the relatively less tension is accumulated loosely and folds because the tension is not the same in the width direction of the fabric, and the third coating method By attaching a knife to the fabric, it is impossible to adjust the thickness of the net.

Second, the transfer method is a method mainly used in the manufacture of dry synthetic leather is a coating method that forms the basis of the domestic PU coating industry, synthetic leather is a multi-layer structure coated with a PU resin based on the brushed fabric of the fabric fabric.

When the above method is applied to the net fabric, there is a problem in that the net transition frame does not have a complete transition effect.

Third, the wet method is a polyurethane wet process that utilizes the strong intermolecular cohesion between the polymers in the wet urethane resin in the solution and the water solubility of DMF used as a solvent, so that the urethane resin solution is immersed in water and then the osmotic pressure principle. The film is formed by the strong intermolecular cohesion of the polymer while extracting the DMF.

The film forming method is a method of directly applying on the processed fabric by the knife over roll method of the working liquid of the wet resin, and a method of applying the wet resin working liquid after applying the knife over method on a smooth film (polyester film, etc.) And, after dipping the fabric in a wet resin working solution and squeeze (squeeze) appropriately is a method of processing after adjusting the coating amount.

The above method also has a problem of disposing the Nip roll and the thickness of the mesh structure frame when applied to the net fabric, the tension of the fabric is not uniform during the process, the film thickness of the coating resin is not constant, and an uneven film is formed. .

In general, in the range of coating processing, the coating speed is 3 to 1,000 m / min, the coating weight is 2 to 35 g / m 2, the coating agent viscosity is 25 to 50,000 cps, the coating solids range from 35 to 65%, etc. Do.

Among various coating processes, a dip coating method (draw down) is most preferred as a coating method applicable to a net fabric.

The immersion coating method causes the resin to adhere to the coated object when lifting the coated object from the resin layer. As time passes, the resin flows downward due to gravity, becomes equilibrium, and the remaining resin finally becomes a resin film. Is fixed and the thickness is determined. The attachment equilibrium thickness t when the fabric is withdrawn from the impregnation tank at a constant speed of 0.5 to 6.4 cm / sec can be expressed by the following equation.

Where v is the moving speed of the fabric, μ is the viscosity of the resin, ρ is the density of the resin, g is the gravitational acceleration, and α is the angle formed by the pull-out tangent to the fabric at the horizontal plane and the liquid contact.

In the above formula, the main variables of the film thickness are the viscosity, density, and fabric speed of the resin, and in order to keep the parameters affected by the liquid temperature such as viscosity and density as constant as possible, liquid temperature management is also required.

An impregnator is a measurement and smoothing at the same time by passing the fabric into the resin bath. The characteristics of the fabric affecting the impregnation include absorbency, porosity, density, degree of processing, size and type. After the fabric is passed through the impregnation solution, the fabric is passed through a metering device such as a knife-shaped resin thickness adjusting device, a pickup roller, a metering roller, or a smoothing roller to control the amount of solution remaining in the fabric. As with the impregnation solution, viscosity and temperature, the temperature of the fabric and its porosity affect the amount of impregnation. The control of the impregnation is mainly done using the metering device and the percent solids of the solution. All other variables are carefully controlled so as not to affect the impregnation volume.

In the rheology of the resin, the flow properties of the resin need to have some degree of thixotropy, wetting, relatively high leveling index, as few as possible foam, and suitable resistance to shear.

In addition, the control technology of the coating apparatus can be largely divided into three control units. These include control around the coating, line control such as tension and processing speed, and dryer control to control the temperature and wind speed of the dryer.

In the impregnation method (Application No. 10-2007-0077868) previously filed by the applicant, the solution impregnated in the fabric is flowed down by gravity to equilibrate, and then the remaining solution is fixed to the coating film and the thickness is determined.

However, the solution viscosity of the impregnation process is used to less than 1,000 cps (measured by Brookfield viscometer LVT spindle 2 #, 20 ℃, 3RPM) is to use a lot of organic solvents.

The demand for functional development and environmental problems in the double production process remain a big challenge. Dip coating impregnation process has a solution viscosity of 1,000 cps (Brookfield viscometer) since the solution impregnated in the fabric is flowed down by gravity to equilibrate and then the remaining solution is fixed to the coating film and the thickness must be determined. LVT spindle 2 #, 20 ℃, measured at 3RPM) should be used to prevent bubbles from drying and curing with uniform impregnation. However, since the volatile organic solvent must be used excessively in order for the solution viscosity to come out, there is a problem of releasing the organic solvent.

Therefore, an object of the present invention is to provide a coating method to enable a dip coating method, even sticky solution viscosity.

To solve this problem, the impregnating solution is combined with the structure of the metering roller (metering roller) and the net fabric of the metering device to the existing dip coating method in which the coating film is formed by gravity.

Mesh coating method and apparatus using a metering roller has an effect that can significantly reduce the volatile organic solvent and improve the productivity.

The present invention relates to a coating device of the net fabric impregnated with a functional coating solution to the net fabric, unwinding part 100 for supplying the net fabric (110), and liquid film removal roller 220 to uniformly impregnate the net fabric , Metering roller 270, deposition adjustment roller 230, drying tower 300 for drying and curing the impregnated fabric, heating upper roller 320, and the fabric conveying roller 400 to convey the coated fabric ), It is characterized by consisting of a winding unit (500).

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to Figure 1 as a process chart showing the impregnation process using a metering roller according to the present invention, it illustrates a coating method of the net fabric impregnated with a functional coating liquid in the net fabric. The unwinding step of supplying the net fabric 110, the impregnation step consisting of a liquid film removal roller 220, a deposition adjusting roller 230, a metering roller 270 to maintain a uniform impregnation and a net structure frame in the net fabric It is characterized in that it comprises a winding step of drying and curing the impregnated fabric and winding the conveyed coated fabric.

The drying tower 300 structure for drying and curing the impregnated fabric consists of a solvent removal section, a section for curing the impregnation solution to a moderate degree, and finally a heating upper roller 320 for completely curing the impregnation solution.

Referring to Figures 2 and 3 as a detailed view of the impregnation process using a metering roller according to the present invention, the metering roller 270 is made of intaglio (even version) of the uniform surface, the intaglio cell (10) It is desirable to have a size of ˜100 mesh (lines / inch).

If it exceeds 100 mesh, the coating solution is uniformly delivered and staining does not occur, but electrical conductivity is not obtained. If it is less than 10 mesh, the amount of coating liquid delivered is large, but staining becomes large, resulting in resistance variation and bubbles during drying.

The progress of the mesh fabric 110 wraps around the outer circumferential surface of the immersion adjustment roller 230 in the immersion barrel 200 more than 180 degrees and flows back into the drying tower 300, the mesh fabric of the impregnation process to remove the liquid film Through the roller 220 and the deposition adjustment roller 230, the surface between the same fabric is in contact with each other and proceed in the opposite direction, the metering roller 270 is in contact with the contact surface 280 between the surface of the same fabric The liquid film removal roller 220, the metering roller 270, and the deposition adjusting roller 230 are not in contact with each other, and the arrangement of the metering roller 270 is based on the fabric film removal roller 220 with the fabric. It is characterized by being made opposite to each other.

The mesh coating method using the metering roller 270 according to the present invention is capable of uniform impregnation process up to 100,000 cps (measured by Brookfield viscometer LVT spindle 1 #, 20 ℃, 3RPM) solution viscosity. In other words, the increase in the viscosity of the coating solution can significantly reduce the volatile organic solvent.

The present invention is a method of using a combination of the structure of the metering roller (metering roller) and the net fabric of the metering device in addition to the existing dip coating method in which the impregnation solution is a coating film is formed by gravity. The surface of the metering roller 270 may form a volume space of intaglio cells to fill the coating solution.

The net fabric 110 is in contact with the outer circumferential surface of the metering roller 270 to form a uniform coating film, the contact surface 280 section between the surface of the same fabric flowing into the immersion barrel 200 is formed It features.

 In addition, the function of the contact surface 280 between the surface of the same fabric can maintain the structure of the mesh fabric by removing the coating liquid film of the mesh fabric.

The coating film may be controlled by adjusting the contact surface 280 between the surfaces of the same fabric through the deposition adjusting roller 230 and the metering roller 270.

Referring to Figure 4, as a detailed view of the contact surface section between the surface of the same fabric according to the present invention, the contact surface 280 section between the surface of the same fabric is the same fabric more than 180 degrees of the outer peripheral surface of the deposition adjustment roller 230 The encapsulation fabric 281 and the extraction fabric 282 are formed to wrap around and scrape off the excess solution by the contact shear force of the fabric 281, and at the same time the surface cell of the metering roller ( cell) the solution in the space is transferred to the withdrawal fabric 282, and the surface of the metering roller is treated with a Teflon coating to increase the solution transfer rate.

The metering roller 270 is characterized in that the coating solution in the cell space recessed in the shape of intaglio (凹版) is transferred to the withdrawal fabric 282 impregnated with the inlet fabric.

In addition, it is characterized in that a uniform coating film is formed by scraping off the excess coating solution on the surface of the draw fabric in contact with the mirroring roller with the draw fabric.

Indicators to consider the coating film thickness are viscosity, surface tension, drying rate, solids of the solution.

The film thickness is determined by the relationship of (cell volume of the metering roller) x (solution transfer rate) x (solution solids), but the solid content is also a parameter for adjusting the viscosity at the same time, so it is necessary to balance with other factors.

Viscosity and surface tension are not only reflected in the staining of the coating film but also affect the solution transfer rate.

The surface tension is characterized by sequentially lowering the surface tension of the mesh fabric, the coating solution, the metering roller 270 to be coated material.

 In particular, in order to increase the solution transfer rate, it is desirable to treat the surface of the metering roller 270 with a Teflon coating.

The shape of the cell is determined by the three elements of the shape, the number of meshes, and the depth represented by pyramids, trapezoids, diagonal lines, and honeycombs.

On the other hand, as the cell depth increases, the coating film thickness may increase proportionally.

In addition, in the present invention, in order to give a uniform double-sided coating on the net fabric in the impregnation process, the coating is made twice, if the contact surface 280 between the surface of the same fabric when the first coating is made between the surfaces (face) , When the secondary coating, the contact surface of the same fabric is characterized in that the back surface (이루어 面) made.

In the above process, a uniform coating film can be formed up to the corner of the mesh fabric lattice point.

1 is a process chart showing an impregnation process using a metering roller according to the present invention

Figure 2 is a detailed view of the impregnation process using a metering roller according to the present invention

Figure 3 is a detailed view of the impregnation amount adjusting process using the deposition adjustment roller according to the present invention

Figure 4 is a detailed view of the contact surface section between the surface of the same fabric according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100: unwinding part

110: netting fabric

111: mesh primary coating fabric

200: deposition barrel

220: liquid film removal roller

230: deposition adjustment roller

270 metering roller

280: contact surface between surfaces of the same fabric

281: pull-in fabric

282: pull out fabric

300: drying tower

320: heating upper roller

330: heat reflection and insulation

400: fabric feed roller

500: winding

510: mesh secondary coating fabric

Claims (6)

The present invention relates to a coating apparatus for a net fabric impregnated with a functional coating solution on a net fabric, the unwinding part 100 for supplying the net fabric 110, and a film removing roller 220 and a metering roller to uniformly impregnate the net fabric. 270), the deposition adjusting roller 230, the drying tower 300 for drying and curing the impregnated fabric, the heating upper roller 320, and the fabric conveying roller 400 for conveying and winding the coated fabric, the winding unit Coating device of the mesh fabric, characterized in that consisting of (500). In the coating method of the net fabric impregnated with a functional coating solution to the net fabric, the unwinding step of supplying the net fabric, Impregnation step consisting of the liquid film removal roller 220, the deposition adjustment roller 230, the metering roller 270 to maintain a uniform impregnation and the net structure frame in the mesh fabric, Drying and curing the impregnated fabric and the coating method of the net fabric comprising a winding step of transporting the coated fabric wound. The mesh fabric of claim 2, wherein the metering roller 270 is formed of an intaglio portion having a uniform surface, and the intaglio cell is formed in a size of 10 to 100 mesh (lines / inch). Coating method. The process of claim 2, wherein the advancing of the mesh fabric 110 is returned to the drying tower 300 by surrounding the outer circumferential surface of the deposition adjusting roller 230 in the deposition vessel 200 and more than 180 degrees, the impregnation process The mesh fabric of the liquid film removal roller 220 and the deposition adjustment roller 230 through the surface between the same fabric is made to proceed in the opposite direction to each other, and the metering roller ( 270 is in contact with each other, the liquid film removal roller 220, the metering roller 270, the deposition adjusting roller 230 is not made in contact with each other, the arrangement of the metering roller 270 is based on the liquid film Removing roller 220 and the coating method of the mesh fabric, characterized in that made to face each other. The contact surface 280 section between the surfaces of the same fabric is wrapped in the outer peripheral surface of the deposition adjusting roller 230 with the same fabric or more, 180 degrees or more, and the pull-in fabric 281 and the pull-out fabric 282 is formed, the excess solution is scraped off by the contact shear force of the incoming fabric 281, and at the same time, the solution contained in the surface cell space of the metering roller is transferred to the extracted fabric 282. ) And the surface of the metering roller is treated with Teflon coating to increase the solution transfer rate. The method of claim 2, wherein in order to apply a uniform double-sided coating to the mesh fabric in the impregnation process, the coating is made twice, and the contact surface 280 between the surfaces of the same fabric during the first coating is formed between the surfaces When the second coating, the coating method of the mesh fabric, characterized in that the contact surface of the same fabric to be made between the back surface (裏面).

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