KR101065764B1 - Analysis of Web Wrinkles and Buckling in Roll-to-Roll Electronic Printing Process - Google Patents

Abstract

The present invention relates to a method for analyzing web wrinkles and buckling in a roll-to-roll (R2R) electronic printing process, comprising: (a) modeling a web on which an ink is printed into a flexible shell and deforming a roller; Modeling a rigid surface free of charge; (b) assembling the modeled web and the roller in abutting contact; (c) simulating a roll-to-roll (R2R) printing process by rotating the web and roller; And (d) numerically analyzing the wrinkles occurring as the web passes through the rollers and the buckle phenomena in which the webs are bent using a finite element program. The method includes a finite element analysis (FEA) program. For the wrinkles caused by the web passing through the rollers and the buckling of the webs during the winding and unwinding processes, which are large defects in the roll-to-roll printing process By numerical analysis, it is possible to secure the reliability of the analysis of the wrinkles and buckling of the web generated in the roll-to-roll printing process while increasing productivity in the actual process and minimizing the economic loss effect.

Description

METHOD FOR ANALYSIS BUCKLING AND WRINKLE OF WEB IN ROLL-TO-ROLL PRINTED ELECTRONICS}

The present invention relates to a method for analyzing web wrinkles and buckling in a roll-to-roll (hereinafter referred to as "R2R") electronic printing process, and more specifically, finite element analysis (FEA). Wrinkles caused by the web moving through the rollers during the winding and unwinding processes, which are large defects in the roll-to-roll (R2R) printing process using a program. The present invention relates to a method for analyzing web wrinkles and buckling in a roll-to-roll (R2R) electroprinting process that numerically analyzes buckling and bending buckling.

In general, finite element analysis (FEA) is a computer simulation technique used for engineering analysis, and uses a numerical technique called finite element method (FEM), and generally through computer-aided engineering (CAE) work. It is composed.

These CAE constructs include modeling processes (pre-processing) for modeling and defining characteristics of finite elements, analysis solvers for solving finite elements, and post-processing for verifying results with visualization tools. It is composed of

First, pre-processing is the first step in finite element analysis (FEA), which models the finite element of the structure to be analyzed. Most finite element analysis (FEA) packages use geometry to represent the geometric features of a structure. It is expressed in 1D, 2D, and 3D forms, and is represented by lines, shapes, and surfaces, respectively.

In recent years, 3D modeling methods have been the main trend. The most important purpose of modeling is how to better represent the actual model. Since most of today's products are designed through CAD work, it is common to use design data for finite element modeling, and most programs support the function of automatically generating finite element models by converting CAD data. At this time, the roughly generated finite element can be largely divided into three parts. One lattice is called a mesh, and a point forming a vertex of the mesh is called a node, and an area of a mesh connected to the node is called an element.

The second step of the finite element analysis (FEA) is an analysis solver, which performs a numerical analysis on the finite element modeling by the data of the finite element modeling input to the finite element analysis program. At this time, if the modeling data is correct and the input value is correct, the result will be derived correctly. The calculation is done by a computer, so the user needs to set exactly what he wants to see.

Finally, the third stage of the finite element analysis (FEA) is post-processing. Analysis results can be confirmed through the finite element analysis program, and can be confirmed through numerical or graph (color map).

In the industrial use of the finite element analysis (FEA), a lot of packages combining CAD and FEA have appeared, and the movement to predict the final phenomenon of the product from the CAD design stage and to reflect it in the design is increasing.

1 is a configuration diagram schematically showing a conventional roll-to-roll (R2R) electronic printing apparatus.

Conventional roll-to-roll (R2R) electronic printing apparatus as shown in Figure 1, nip roll (Nip Roll; 110), Web (120), Gravure Roll (130), which operates as an imprinting roller, Doctor blade (140), ink filling tank (150), conductive ink contained in the ink filling tank (150) to scrape the ink on the roll surface evenly during gravure printing, And a laser drying device 170.

Here, the nip roll 110 operates as a pressure roller and is composed of a backing roll and a nip, and is configured to transfer the ink remaining in the gravure cell to the printed matter. The web 120 refers to a printed matter on which ink is printed, and is usually composed of a polymer, and the gravure roll 130 is formed of a recessed line part (cell) formed as a type of plate printing. The ink of 150 is transferred to the nip roll 110. The doctor blade 140 functions to scrape off excess ink remaining on the surface of the gravure roll 130 sent out from the ink filling tank 150. The laser drying apparatus 170 is mounted on a general dryer part, and functions to dry or cure the electronic ink 122 by irradiating a laser to the electronic ink 122 buried in the web 120.

The conventional numerical analysis method for analyzing the wrinkles or buckling that occurs on the web in a conventional roll-to-roll (R2R) electronic printing apparatus only models the web without considering the roller. Modeling and modeling only the roller and the web without considering the temperature conditions that occur in the process of rotating the roller web, and then numerically analyzed by assembly (assembly). In addition, in numerical analysis, there are many differences in the boundary conditions applied to the web and the roller, and thus, there is a problem in that the actual wrinkle wrinkle phenomenon of the web is not performed in the roll-to-roll printing process.

The technical problem to be solved by the present invention is to solve the above problems, the winding and unwinding process, which is a large defect that occurs in the roll-to-roll (R2R) printing process using a finite element analysis (FEA) program Web wrinkles in a roll-to-roll (R2R) electroprinting process that numerically analyzes the wrinkling that occurs during the web's trip through the roller and the buckling that the web bends during And a method of analyzing the buckling phenomenon.

In addition, another technical problem to be achieved by the present invention is a nonlinear finite element considering various contact conditions between the web boundary condition and the web boundary condition when the web rotates the roller through a numerical analysis process using a finite element analysis (FEA) program. The purpose of the present invention is to present a method for analyzing web wrinkles and buckling in a roll-to-roll (R2R) electronic printing process that performs numerical analysis using a nonlinear finite element method.

In addition, another technical problem to be achieved by the present invention, by considering the temperature in the contact conditions of the web and the roller in the numerical analysis process using the finite element analysis (FEA) program, by applying the appropriate contact conditions between the web and the roller, Roll-to-roll (R2R) electrons can be used to increase the productivity and minimize the economic loss in the actual process, while ensuring the reliability of the analysis of web wrinkles in the roll-to-roll (R2R) printing process. The purpose of this study is to present a method for analyzing web wrinkles and buckling in the printing process.

In addition, another technical problem to be achieved by the present invention is to assemble by modeling the web as a thin shell (rolling) as a rigid shell (rigid surface) in the numerical analysis process using a finite element analysis (FEA) program, The present invention provides a method for analyzing web wrinkles and buckling in a roll-to-roll (R2R) electronic printing process that can substantially apply a phenomenon that a web passes through a roller.

As a means for solving the above-described technical problem, the invention described in claim 1, "In the web wrinkle and buckling phenomenon analysis method of the roll-to-roll (R2R) electronic printing process, (a) a web on which ink is printed Modeling the roller as a flexible shell and modeling the roller as a rigid surface without deformation; (b) assembling the modeled web and the roller in abutting contact; (c) simulating a roll-to-roll (R2R) printing process by rotating the web and roller; And (d) numerically analyzing the fold phenomenon occurring as the web passes through the roller and the buckling phenomenon in which the web is bent using a finite element program. to provide.

According to the invention of claim 2, "The web wrinkle and buckling phenomenon analysis method according to claim 1 is a web wrinkle and buckle, characterized in that for applying the boundary conditions of the web during numerical analysis using the finite element program Ring phenomenon analysis method.

According to the invention of claim 3, the method according to claim 1, wherein the web wrinkle and buckling analysis method is adapted to apply a surface-to-surface contact condition between the web and the roller during numerical analysis using the finite element program. Web wrinkle and buckling analysis method.

The invention as set forth in claim 4, "The method according to claim 3, wherein the web wrinkle and buckling phenomenon analysis method: applies a limited sliding contact condition between the web and the roller during numerical analysis using the finite element program. Web wrinkle and buckling analysis method.

According to the invention of claim 5, "The method for analyzing web pleat and buckling phenomenon according to claim 4 is characterized by: applying contact between the web and the roller by an isotropic Coulomb friction acting tangentially. Web wrinkle and buckling phenomenon analysis method.

The invention according to claim 6, wherein the web wrinkle and buckling analysis method according to claim 4 includes: the web and the roller when analyzing the wrinkle phenomenon of the web through numerical analysis using the finite element analysis program. Web wrinkle and buckling phenomenon analysis method characterized in that the analysis in consideration of the temperature in the contact conditions of.

According to the present invention, the web is used to rotate the rollers during the winding and unwinding processes, which are large defects occurring in a roll-to-roll (R2R) printing process using a finite element analysis (FEA) program. Numerical analysis can be performed on the wrinkling and buckling of the web.

In addition, the numerical analysis process using the finite element analysis (FEA) program uses a nonlinear finite element method that considers the boundary conditions of the web and various contact conditions between the web and the roller when the web rotates the roller. Numerical analysis can be performed.

In addition, the web generated in the roll-to-roll (R2R) printing process by considering the temperature in the contact condition between the web and the roller and applying the appropriate contact condition between the web and the roller in the numerical analysis process using the finite element analysis (FEA) program. In addition to ensuring the reliability of the analysis of wrinkles, the results of these analyzes can be used to increase productivity and minimize economic losses in the actual process.

In addition, in the numerical process using the finite element analysis (FEA) program, the web is modeled and assembled into a thin shell and the roller is a rigid surface, thereby substantially applying the phenomenon of the web passing through the roller. Numerical interpretation.

The problem of the present invention is not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a schematic view showing a conventional roll-to-roll (R2R) electronic printing apparatus
2 to 4 are modeling and web (web) and roller (roller) for the numerical analysis using the finite element analysis program in the web wrinkle and buckling phenomenon analysis method of the roll-to-roll (R2R) electronic printing process according to the present invention As assembled drawings,
2 is a schematic diagram of a web modeled as a thin shell,
3 is a schematic of modeling a roller as a rigid surface,
4 is a schematic view of assembling a web and a roller.
FIG. 5 is a diagram illustrating boundary conditions applied to a web during numerical analysis using a finite element analysis program. FIG.
6 shows contact conditions applied between a web and a roller;
7 is a flowchart illustrating a web wrinkle and buckling analysis method of the roll-to-roll (R2R) electronic printing process according to a preferred embodiment of the present invention

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Example

2 to 4 are modeling and web (web) and roller (roller) for the numerical analysis using the finite element analysis program in the web wrinkle and buckling phenomenon analysis method of the roll-to-roll (R2R) electronic printing process according to the present invention 2 is a schematic diagram of a web modeled as a thin shell, FIG. 3 is a schematic diagram of a roller modeled as a rigid surface, and FIG. This is a schematic view of the assembly of a web and a roller. FIG. 5 is a diagram showing boundary conditions applied to a web during numerical analysis using a finite element analysis program, and FIG. 6 is a diagram showing contact conditions applied between a web and a roller. .

First, the web wrinkle and buckling phenomena analysis method of the roll-to-roll (R2R) electronic printing process according to the present invention for the numerical analysis using the finite element analysis program, the web is modeled as a thin shell (roller) By modeling a rigid surface without deformation and then assembling the two models, the web can be passed through the rollers. The core of the present invention is the numerical analysis through the nonlinear finite element method considering the boundary conditions of the web and the various contact conditions between the web and the roller when the web rotates the roller in the numerical analysis process using the finite element program. To do. Unlike the existing numerical analysis process for analyzing wrinkles on webs, considering the temperature conditions and applying the appropriate contact conditions between the web and the rollers, the analysis of the wrinkles on the webs in the roll-to-roll printing process It is a numerical analysis technique using finite element program that can increase the productivity and minimize the economic loss effect in the actual process based on the results of this analysis while ensuring reliability.

2 and 3, the web is modeled as a flexible thin shell, and the roller is modeled as a rigid surface without deformation, and the numerical analysis is performed using a finite element analysis program. The basic method is to add accuracy and reliability to the analysis of the wrinkles of the web in the roll-to-roll (R2R) printing process. Modeling the roller as a rigid surface without deformation can reduce the analysis time.

First, the modeled web and the roller are assembled such that the web and the roller come into contact with each other (zero gab) as shown in FIG. 4. This can be said to be a modeling process suitable for the actual process line by performing a real simulation (simulation) for the roll-to-roll (R2R) printing process. In addition, in the numerical analysis process, one of the edges in the longitudinal direction of the web as shown in FIG. 5 is different from the conventional methods such as simultaneously applying the tensile force to both edges of the web in the longitudinal direction or distributing the tensile force and the fixed condition at both edges. By applying a constant force to the edges, applying displacement conditions to the other edge, and applying a free state to both edges in the width direction, simulates the crease of the web during the actual roller-to-roll (R2R) printing process. can do.

In addition, as the displacement condition is applied to one edge of the web in the longitudinal direction as shown in FIG. 6, the numerical analysis is performed by applying a contact condition between the web and the roller while the web rotates the roller. The contact between the web and the roller then applies a surface to surface contact and a sliding formulation with limited finite sliding. Specifically, the contact between the web and the roller is applied by tangential behavior of isotropic coulomb friction, which slides in the longitudinal direction of the web so that the web can rotate freely as it rotates the roller. No sliding condition is applied, and a certain coefficient of friction is applied in the width direction of the web.

When this contact condition is applied, the web rotates the roller so as to match a specific displacement value applied to one edge of the web in the longitudinal direction as shown in FIG. 5 to simulate the behavior of the actual web rotating the roller. have. In addition, by applying the temperature conditions at the contact surface between the web and the roller considering the characteristics of the roll-to-roll printing process including the printing and drying processes, more accurate simulation results are obtained by more realistic simulation of the wrinkles of the web generated in the process line. Can be obtained.

Numerical results of web wrinkles generated in the roll-to-roll (R2R) process by this process can be printed more economically and with higher stability by identifying and reducing the factors of web wrinkles that greatly reduce the productivity of the process line. Do it.

7 is a flowchart illustrating a web wrinkle and buckling analysis method of the roll-to-roll (R2R) electronic printing process according to a preferred embodiment of the present invention.

Web wrinkle and buckling analysis method of the roll-to-roll (R2R) electronic printing process according to the present invention, as shown in Figure 7, first, the web (ink) is printed on the web (web) as a flexible shell (shell) and roller ( The roller is modeled as a rigid surface without deformation (step S110).

Then, the modeled web and the rollers are assembled so as to contact with each other (step S120). This is a modeling process suitable for the actual process line by performing a realistic simulation for the roll-to-roll printing process.

Then, the web and the roller are rotated to perform a substantial simulation for the roll-to-roll (R2R) printing process (step S130).

Finally, numerical analysis is performed by using a finite element program on the wrinkle phenomenon caused by the web passing through the roller and the buckling phenomenon that the web is bent (step S140).

Here, the web wrinkle and buckling phenomenon analysis method is applied by applying the boundary condition of the web in the numerical analysis using the finite element program, by applying the surface-to-surface contact condition between the web and the roller.

In addition, in the numerical analysis using the finite element program, a limited sliding contact condition between the web and the roller is applied, and the contact between the web and the roller is applied by an isotropic Coulomb friction acting tangentially.

The contact between the web and the roller is applied by isotropic coulomb friction acting tangentially so that there is no slip so that the web can rotate freely when the roller rotates in the longitudinal direction of the web. Apply a specific coefficient of friction in the width direction. When such contact conditions are applied, the web rotates the roller to match a specific displacement value applied to one edge of the web in the longitudinal direction, thereby simulating the behavior when the actual web rotates the roller.

In addition, the web wrinkle and buckling phenomenon analysis method is generated in the process line in consideration of the temperature of the contact conditions of the web and the roller when analyzing the wrinkle phenomenon of the web through the numerical analysis using the finite element analysis program More realistic simulation of wrinkles on the web can provide accurate numerical results.

Web wrinkle and buckling analysis method of the roll-to-roll (R2R) electronic printing process according to the present invention configured as described above is a large defect that occurs in the roll-to-roll (R2R) printing process using a finite element analysis (FEA) program By numerically analyzing the wrinkles and buckling that the web bends as the web moves through the rollers during winding and unwinding, The technical problem of this invention can be solved.

It will be apparent to those skilled in the art that various modifications and changes can be made in the present invention without departing from the spirit or scope of the present invention as defined by the appended claims. It will be appreciated that such modifications and variations are intended to fall within the scope of the following claims.

Claims (6)

In the analysis method of the web wrinkle and buckling phenomenon of the roll-to-roll (R2R) electronic printing process,
(a) modeling the web on which the ink is printed into a flexible shell and modeling the roller as a rigid surface without deformation;
(b) assembling the modeled web and the roller in abutting contact;
(c) simulating a roll-to-roll (R2R) printing process by rotating the web and roller; And
(d) numerical analysis using a finite element program for pleat phenomena occurring as the web passes through the rollers and buckling for the web to bend;
Web wrinkle and buckling phenomenon analysis method comprising a.
The method of claim 1, wherein the web wrinkle and buckling analysis method comprises:
Web wrinkle and buckling phenomenon analysis method characterized in that for applying the boundary conditions of the web when numerical analysis using the finite element program.
The method of claim 1, wherein the web wrinkle and buckling analysis method comprises:
And a web surface and surface contact condition between the web and the roller during numerical analysis using the finite element program.
The method of claim 3, wherein the web wrinkle and buckling analysis method is:
The web wrinkle and buckling phenomenon analysis method, characterized in that for applying a limited sliding contact condition between the web and the roller in the numerical analysis using the finite element program.
The method of claim 4, wherein the web wrinkle and buckling analysis method is as follows:
And analyzing the contact between the web and the roller by applying an isotropic Coulomb friction acting tangentially.
The method of claim 4, wherein the web wrinkle and buckling analysis method is as follows:
When analyzing the wrinkle phenomenon of the web through the numerical analysis using the finite element analysis program, web wrinkle and buckling phenomenon analysis method characterized in that the analysis in consideration of the temperature of the contact conditions of the web and the roller.

Images