KR20190126472A - Apparatus and method for testing adhesion force of coating layer - Google Patents

Abstract

The present invention relates to a device and a method for testing an adhesion force of a coating layer. The main purpose of the present invention is to provide the device and the method for testing an adhesion force of a coating layer, capable of objectively, quantitatively, and accurately testing an adhesion force of a coating layer on a substrate on a specimen having the coating layer on the surface of the substrate. To achieve the purpose of the present invention, the method for testing an adhesion force of a coating layer includes: a step of manufacturing the specimen having the coating layer on the surface of the substrate; a step of bonding a loading plate to the coating layer of the specimen by an adhesive; a step of installing the specimen in a lower jig and connecting the loading plate to an upper jig; a step of operating an operation unit operating to vertically ascend and descend by a driving device in a main body of the loading device and applying a tensile load to the coating layer of the specimen by the loading plate and the upper jig installed in the operation unit as the operation unit ascends by being operated by the driving device; a step of gradually increasing the load applied; and a step of measuring a maximum tensile load when at least a part of the coating layer of the specimen bonded to the loading plate by the tensile load is separated from the substrate while the tensile load is increased, and of calculating the adhesion force of the coating layer based on the maximum tensile load measured.

Description

Apparatus and method for testing adhesion force of coating layer

The present invention relates to an apparatus and method for evaluating coating film adhesion, and more particularly, to an apparatus and method for evaluating coating film adhesion on an object, objectively and quantitatively, with respect to a specimen on which a coating film is formed on a substrate surface. .

As is known, forming a coating film on the surface of a part, an article, a product, an apparatus, a structure, etc. is widely practiced industrially.

When the part that forms the surface on which the coating film is formed in the part, article, product, apparatus, structure, or the like is referred to as the substrate, the material or material of the substrate on which the coating film can be formed varies greatly.

Also in the coating film, various kinds of coating films are known in terms of functions, functions, uses, purposes, and materials forming the coating film.

For example, the surface of an automotive part, in particular a surface of a steel plate or a plastic material that is a vehicle body or a chassis part, is coated for improving appearance or preventing corrosion, or a coating is formed by coating a material having a specific function and effect.

Here, an example of the painting of the vehicle will be described in more detail as follows.

In general, the vehicle coating process is a process of forming an electrodeposition layer by electrodeposition on the steel plate for vehicle outer plate, forming a middle coating film on the surface of the electrodeposition layer, and hardening it, and coating a top coat as a color base on the surface of the middle coating film. The process of forming a coating layer, the process of forming a coating layer by apply | coating a transparent coating agent to the surface after setting of a top coat layer, etc. are performed.

The coating film coated on the vehicle may be classified into electrodeposition, intermediate, color base, and transparent coating. The four coating films may be formed of different materials, respectively, and the purpose of painting is also different.

As such, the coating process undergoes intermediate and top coat treatments in order to increase adhesion to the surface. However, since the coating process is greatly influenced by the product shape, the product shape also has a great effect on the coating performance.

In particular, since the adhesion of the coating film is lower than the flat surface in the curved surface portion with curvature, the painting on the curved surface requires careful attention.

Therefore, most automobile companies evaluate the coating film adhesion to confirm the coating film adhesion performance, and performs a water resistance evaluation to check the watertight performance of the paint.

Since paints used in vehicles are mostly organic materials, they are easy to change due to sunlight and weather.As a result, coating performance deteriorates, which can be a starting point for corrosion in the case of exterior parts. If this is revealed, the appearance may be greatly reduced, and weather resistance evaluation is also performed.

As described above, the vehicle coating and the coating performance evaluation have been briefly described. However, the coating film is not only intended for the vehicle, but the coating film is applied to various parts, articles, products, devices, structures, etc. industrially. Accurate and quantitative evaluation is required in performance, such as the adhesion of the coating film to the target surface.

As a related prior patent document, Korean Patent No. 10-0693070 (2017.03.212.) Discloses a method for testing the adhesion of a transparent conductive film coated on a substrate, and repeatedly applying a load to a test piece by means of a resistance sensor. The load at which breakage of the transparent conductive film occurs is measured using the measured resistance value.

In addition, Korean Patent Laid-Open Publication No. 10-2015-0031617 (2015.03.25.) Discloses a method of measuring the integrity of a TSA (Thermal Spray Aluminum) coating on the back surface of a weld.

In addition, an X-cut method, a cross-cut method, a dolly test, and the like are known.

However, conventionally, there is no method for quantitatively evaluating adhesion to the coating film specimen, and it is true that all known conventional evaluation methods are insufficient in terms of objectivity of adhesion evaluation.

Accordingly, the present invention has been made to solve the above problems, and provides an apparatus and method for evaluating coating adhesion, which can objectively and quantitatively accurately evaluate coating adhesion on a substrate with respect to a specimen having a coating formed on the surface of the substrate. The purpose is.

In order to achieve the above object, according to an aspect of the present invention, the main body has an operating part which is operated to move up and down by a driving device, and when the operating part is operated to apply a tensile load to act on the coating film of the specimen. Load application device; An upper jig installed in the operating part and to which a load applying plate is coupled; And a lower jig installed on a table of the load application device, on which a specimen in a state in which the load application plate is adhered to the surface of the coating film formed on the substrate is mounted, wherein the load application device is operated by the operation unit to rise. The tensile load is applied to the coating film of the specimen through the upper jig and the load application plate, and the tensile load when at least a portion of the coating film adhered to the load application plate is separated from the substrate of the specimen by the tensile load. Provided is a coating film adhesion evaluation device, characterized in that.

And, according to another aspect of the invention, the step of preparing a specimen in which a coating film is formed on the surface of the substrate; Adhering a load-applying plate to the coating film of the specimen with an adhesive; Mounting the specimen on a lower jig and coupling the load applying plate to an upper jig; In the main body of the load-applying device to operate the operating part to move up and down by the driving device, the operation of the test piece through the upper jig and the load applying plate installed in the operating part as the operating part is operated by the driving device to raise Allowing a tensile load to be applied to the coating film; Gradually increasing the applied load; And a maximum tensile load when at least a portion of the coating film of the specimen bonded to the load-applying plate by the tensile load while the tensile load is increased is measured from the substrate, and the coating film adhesion force is calculated from the measured maximum tensile load. It provides a coating film adhesion evaluation method comprising the step.

Thus, according to the coating film adhesion evaluation apparatus and method according to the present invention, it is possible to quantify the adhesive force through the control of the evaluation factors in comparison with the prior art that the evaluation of the adhesion between the substrate of the specimen and the coating film depending on the visual shape The reproducibility and reliability of the coating film evaluation method can be increased.

1 is a front view of the coating film adhesion evaluation apparatus according to the present invention.
2 is a view for explaining a method for fixing by applying a load applying plate to the specimen in the present invention.
Figure 3 is a perspective view showing a state in which the load application plate is coupled to the upper jig in the present invention.
Figure 4 is a perspective view showing a state in which the specimen is coupled to the lower jig in the present invention.
5 is a perspective view showing a state when a load is applied in a state where the load application plate and the coating film of the specimen are attached in the present invention.
6 is a diagram schematically showing a pretreatment of a load applying plate in the present invention.
7 is a diagram illustrating the results of a pull-off test according to an embodiment of the present invention.
8 is a flowchart illustrating a coating film adhesion evaluation process according to the present invention.
9 is a view showing a state in which the coating film is attached to the load applying plate after being detached from the substrate in an embodiment of the present invention.
10 to 12 are views showing the measurement results of the load at the time of coating film adhesion evaluation in each embodiment of the present invention.

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. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise.

The present invention relates to an apparatus and method capable of evaluating the adhesion between the substrate and the coating film on a specimen having a coating film formed on the surface of the substrate.

More specifically, the present invention relates to a coating film adhesion evaluation apparatus and method that can more accurately and objectively and quantitatively evaluate the adhesion of the coating film on the substrate of the specimen.

Referring to the drawings, Figure 1 is a front view of the coating film adhesion evaluation apparatus 100 according to the present invention, Figure 2 is a method for bonding and fixing the load applying plate 124 to the specimen 10 in the present invention It is a figure for demonstrating.

Figure 3 is a perspective view showing a state in which the load applying plate 124 is coupled to the upper jig 121 in the present invention, Figure 4 shows a state in which the specimen 10 is coupled to the lower jig 123 in the present invention. One perspective view.

5 is a perspective view illustrating a state when a load is applied in a state where the load applying plate 124 and the coating film 12 of the specimen 10 are attached to the present invention.

First, the coating film adhesion evaluation apparatus 100 according to the present invention may have a configuration in the form of an evaluation device that pulls the coating film 12 from the substrate 11, that is, a pull-off tester.

There is no particular limitation on the material or material constituting the substrate 11 of the specimen 10 to be evaluated in the present invention, the coating film 12 of the specimen 10 is also not particularly limited in the material or material.

For example, the test piece 10 having the polymer coating film 12 formed on the surface of the substrate 11 made of metal or synthetic resin can be used as the evaluation target.

In addition, the plate-shaped test piece 10 in which the coating film 12 of predetermined thickness was formed in the surface of the board | substrate 11 can be used for evaluation object.

Looking at the configuration in more detail, the coating film adhesion evaluation apparatus 100 according to the present invention includes a load applying device 110 for applying a tensile load to be applied to the coating film 12 of the specimen (10).

The load application device 110 has an operating unit 115 that moves up and down by the drive unit 114 in the main body 111, so as to apply a tensile load as the operating unit 115 operates. It is composed.

In addition, the coating film adhesion evaluation apparatus 100 according to the present invention includes an upper jig 121 installed on the operating unit 115, more specifically, coupled to the mounting unit 120 of the operating unit 115, The load applying plate 124 is coupled to the upper jig 121.

The load-applying plate 124 acts as a coating film 12 of the specimen 10 by applying a tensile load applied by the operation of the operating unit 115 in a state in which it is attached to the coating film 12 of the specimen 10.

In addition, the coating film adhesion evaluation apparatus 100 according to the present invention includes a lower jig 123 fixed to the table 112 of the load application device 110, the lower jig 123 is a specimen 10 to be evaluated ) Is mounted.

In this configuration, the load applying device 110 is capable of applying a tensile load to the specimen 10 by the operation of the operating unit 115, that is, a tensile test is possible by applying a tensile load to the specimen 10 Universal Testing Machine (UTM) is available.

The universal testing machine (UTM) is provided with an operating unit 115 (which may be a cross head) that is operated to move up and down by the drive unit 114 from the main body 111, and this operating unit 115 If it is possible to apply a tensile load to the specimen 10 through the mounting portion 120 and the upper jig 121 coupled to the mounting portion 120 integrally provided with the operating unit 115, One of the universal testing machines known in various forms is acceptable.

A general universal testing machine measures the tensile load applied in real time while applying the tensile load to the specimen 10, and acquires the measurement result and the information such as tensile strength obtained from the computer 131 of the control device 130. And, it is configured to display the measured and acquired results through the monitor 132 in the control device 130, if the configuration including such a control device 130, the application to the load applying device 110 in the present invention is It is possible.

In addition, even if it is not a universal testing machine, a tensile load is applied to the coating film 12 of the test piece 10 to separate the coating film 12 from the substrate 11 of the test piece 10 and to pull the coating film 12 apart. If it is a tensile test apparatus that can measure the load, it is possible to apply to the load applying device 110 in the present invention.

In the universal material tester (UTM) illustrated in FIG. 1, the operation unit 115 is provided to move up and down along the guide frame 113 of the main body 111 by the driving unit 114, and the operation unit 115. The tensile force, which is a force to move upward, that is, a force provided when the operating unit 115 rises, is applied to the coating film of the specimen 10 through the mounting unit 120, the upper jig 121, and the load applying plate 124. It is intended to be applied to (12).

As such, various types of universal testing machine capable of applying tensile loads are already known, and since the device configuration of the universal testing machine is already known to those skilled in the art, the apparatus of universal testing machine Detailed description of the configuration will be omitted.

Referring to FIG. 1, an example of the universal testing machine is briefly illustrated. As illustrated, the universal testing machine, which is a load applying device 110, includes a main body 111, and the main body 111 is disposed on both sides of the upper and lower sides. It has a guide frame 113 which is vertically arranged as long.

In addition, the main body 111 has a table 112 on which the specimen 10 as a test object is placed, and a driving device 114 may be built in the lower part of the main body 111.

In the present invention, the universal testing machine further includes a cross head 115 which is an operating unit 115 coupled to the guide frame 113 of the main body 111 to move up and down, wherein the cross head 115 is the main body. It moves up and down along the guide frame 113 of the main body 111 by the drive apparatus 114 built in the lower part (111).

The driving device 114 is provided between the driving motor 116 embedded in the lower part of the main body 111 and between the driving motor 116 and the cross head 115 to move up and down of the cross head 115. It may be to include a power conversion mechanism for converting the rotational force of the 116 to a linear movement force to transmit to the cross head (115).

The power conversion mechanism may include a ball screw 118 which is respectively installed on the left and right guide frames 113 of the main body 111, the ball screw 118 is the lower end of the drive motor through the gear box 117 It is installed so as to be disposed long in the guide frame 113 up and down in a state connected to the (116).

The cross head 115 is installed to be horizontally disposed horizontally between the left and right guide frames 113 of the main body 111, and both ends of the cross head 115 are slidably coupled to the guide frame 113. do.

In addition, both ends of the cross head 115 are screwed to the ball screw 118 embedded in the left and right guide frame 113, respectively, whereby the ball screw when the ball screw 118 is rotated by the drive motor 116 The cross head 115 screwed to 118 moves up and down along the guide frame 113.

In this configuration, the force that the cross head 115 moves upward acts as a tensile load on the specimen 10 through the mounting portion 120, the upper jig 121, and the load applying plate 124.

Meanwhile, the upper jig 121 may be coupled to the mounting portion 120 of the cross head 115 through a connecting ring 122, and the lower jig 123 may be lower than the guide frame 113 in the main body 111. It is fixedly installed on the upper surface of the table 112 located in.

In the present invention, the upper jig 121 is bonded to the coating film 12 of the specimen 10 by the adhesive 14 to the tensile load provided by the load applying device 110 (ie universal testing machine (UTM)) The load applying plate 124 applied to the specimen 10 through the coating film 12 is detachably coupled.

In addition, a specimen 10 is detachably coupled to the lower jig 123, where the specimen 10 may be formed with a coating film 12 having a predetermined thickness on the surface of the substrate 11 as described above. .

In the specimen 10, the coating film 12 may be a polymer coating film 12.

In addition, the load applying plate 124 may be a metal plate including aluminum, and the adhesive 14 adheres and fixes the load applying plate 124 to the coating film 12 of the specimen 10. It is for.

In the present invention, since the adhesive 14, it should be able to strongly adhere between the load plate 124 of the metal material and the polymer coating film 12 of the specimen 10, the adhesion of the heterogeneous material can be produced while high adhesion Possible adhesives 14 are used.

For example, an epoxy-based resin exhibiting adhesion and a hardener necessary for curing by heat may be used.

As a more specific example, those containing bisphenol A-epoxy resins may be used.

In addition, before bonding the load-applying plate 124 to the coating film 12 of the specimen 10, as shown in FIG. 2, a spacer 13 having a predetermined size is uniformly formed on the surface of the coating film 12 of the specimen 10. It is desirable to fix it so as to have one distribution.

The spacer 13 serves to keep the minimum gap between the coating film 12 and the load application plate 124 constant, and also distributes the adhesive 14 between the coating film 12 and the load application plate 124. Make uniform and at the same time serves to make the thickness of the adhesive 14 constant.

Then, after the adhesive 14 is applied to the adhesive region (designated by reference numeral 'B' in FIG. 2) on the surface of the coating film 12 of the specimen 10, the adhesive region B on the surface of the coating film 12 is applied. The load applying plate 124 is bonded and fixed by the adhesive 14.

At the time of bonding, the adhesive 14 is evenly applied between the adhesive region B on the surface of the coating film 12 and the load applying plate 124 and then cured by applying heat and pressure. ) Can be completely fixed to the surface of the coating film 12 of the specimen (10).

At this time, the surface of the coating film 12 of the specimen 10 is partitioned by an appropriate area, and the partitioned area having a predetermined size located at the center on the surface of the coating film 12 is defined as the adhesive region B, and then the predetermined adhesive region B is defined. The adhesive 14 is evenly applied.

Referring to FIG. 2, it can be seen that the adhesive region B having an area of a predetermined size is partitioned in the coating film 12 of the specimen 10. As illustrated, the adhesive region B is surrounded by the coating film 12. It can be partitioned to have a structure that is completely disconnected from the region, that is, a structure that is completely disconnected between regions.

To this end, it is possible to manufacture the specimen 10 by forming the coating film 12 first and then cutting the coating film 12 through the post-processing or removing the coating film 12 of the broken portion, but the coating film 12 is In the process of forming a separate separation wall between the region and the region to form a coating film 12 only in the inner region of the separation wall and later to remove the separation wall to produce a coating film 12 between the region and the disconnected state It is also possible.

The spacer 13 may also be disposed after the coating film 12 is formed or fixed to the coating film 12 in the process of forming the coating film 12.

In the present invention, in bonding the specimen 10 and the load-applying plate 124 with the adhesive 14, the spacer 13 is used to obtain a constant thickness of the adhesive 14, and preferably the particle size of the micrometer scale Branches micro-spacer 13 may be used.

Further, the micro-spacer 13 is added and dispersed in a volatile solvent such as ethanol, and then the solvent (spray liquid) in which the spacer 13 is dispersed is evenly sprayed onto the surface of the coating film 12 of the specimen 10 with a spray mechanism. The solvent may then be evaporated to allow the micro-spacer 13 to adhere to the surface of the coating film 12 of the specimen 10 in an even distribution.

The spacer 13 allows the coating film 12 and the load applying plate 124 of the specimen 10 to maintain a constant gap therebetween, and the coating film 12 and the load applying plate maintaining the predetermined gap. The adhesive 14 can be evenly distributed between the 124.

Accordingly, the adhesive region B on the surface of the coating film 12 and the load applying plate 124 are uniformly distributed between the adhesive region B on the surface of the coating film 12 and the load applying plate 124. This can be firmly bonded.

In addition, the specimen 10 can be fixed to the lower jig 123 and the load applying plate 124 to the upper jig 121 by fixing the load applying plate 124 to the specimen 10. Alternatively, the specimen 10 and the load applying plate 124 may be adhered later in a state in which the specimen 10 is first bonded to the lower jig 123 and the load applying plate 124 is first attached to the upper jig 121.

Referring to FIGS. 3 and 4, the specimen 10 and the load applying plate 124 may be manufactured to have a long rectangular shape in one direction, and are loaded onto the surface of the coating film 12 of the specimen 10. The application plate 124 is vertically lowered and bonded.

In addition, when bonding, the rectangular specimen 10 and the load applying plate 124 may be disposed so as to cross at right angles to each other in the longitudinal direction.

At this time, the upper jig 121 is formed with a coupling groove 125 to which the load applying plate 124 is horizontally inserted and slide-coupled, and the lower jig 123 is fastened by fastening both ends of the specimen 10. Fastening mechanism 126 is provided.

The fastening mechanism 126, as shown, the bolt member 127 is inserted and screwed perpendicularly to the fastening hole formed in the upper surface of the upper jig 121 and the bolt member 127 through the coupling And pressurizing the end of the test piece 10 by the bolt member 127 to include an urging member 128 for pressing and fixing the end of the test piece 10 to the upper surface of the upper jig 121.

In the fastening mechanism 126, when the bolt member 127 is rotated, the pressing member 128 presses both ends of the specimen 10 from the upper side to be pressed and fixed to the upper surface of the lower jig 123.

In addition, the upper jig 121 and the lower jig 123 may be manufactured to have a 'c' shape as a whole, and as shown in FIG. 5, the upper jig 121 having a load applying plate 124 coupled thereto And the lower jig 123 in a state in which the specimen 10 is coupled to each other so that they may be disposed at right angles.

As a result, the load applying plate 124 and the specimen 10 are coupled to the upper jig 121 and the lower jig 123 in the coating film adhesion evaluation apparatus 100 of the present invention having a device configuration of a pull-off tester. The load applying device 110 is operated in a state such that the tensile load is applied to the specimen 10 through the upper jig 121.

At this time, while the specimen 10 is coupled to the lower jig 123 and fixed, the cross head 115, which is an operating part, rises vertically upward, and the upper jig 121 and the load applying plate coupled to the mounting part 120. A tensile load is applied to the coating film 12 side of the specimen 10 through 124, thereby separating the coating film 12 to which the tensile load is applied from the specimen 10 from the substrate 11.

That is, the coating film 12 is pulled off from the substrate 11 by being pulled off, and in this process, the load applying device 110 detachably, that is, a tensile load applied through the upper jig 121 is quantitatively. Is measured.

FIG. 2 is a perspective view illustrating an example in which the load applying plate 124 is coupled to the specimen 10, and as shown, the spacer 13 is evenly disposed on the surface of the coating film 12 of the specimen 10. The adhesive 14 is applied to the adhesive region B in the center in the state, and the load applying plate 124 is lowered vertically from the upper side in a state where the load applying plate 124 is crossed at right angles to the specimen 10. It is bonded to the surface of the coating film 12 of the test piece 10.

The adhesive 14 is then cured by applying heat and pressure so that the load-applying plate 124 can be completely adhered and fixed by the adhesive 14 to the adhesive region B on the surface of the coating film 12.

In the present invention, the specimen 10 and the load-applying plate 124 are bonded to each other by using a heterogeneous material adhesive 14 having a high adhesive force, and at this time, the specimen 10 and the load-applying plate 124 exhibit high adhesive force, Later, when a large tensile load of a predetermined level or more is applied, the coating film 12 can be torn off from the substrate 11.

On the other hand, the load application plate 124 in the present invention can be made of a metal as described above, so that the adhesive force by the adhesive 14 can be improved, that is, applying the load for the purpose of improving the adhesive force of the adhesive 14 Plate 124 may be pretreated.

6 is a schematic diagram showing the pretreatment of the load-applying plate 124 in the present invention, after the pre-treatment process for improving the adhesion to the load-applying plate 124 of the metal material evaluation of the coating film adhesion (pull- off test).

In the present invention, the pretreatment process may be performed by exposing the load application plate 124 to ultraviolet light or irradiating the ultraviolet light to the load application plate 124 as a pretreatment process of the load application plate 124 for enhancing adhesion.

When the surface of the loading plate 124 is exposed to ultraviolet rays in this way, the functional group is activated on the surface of the loading plate 124 to exhibit higher adhesion.

FIG. 7 illustrates the results of a pull-off test according to the present invention. The upper jig 121 is coupled to the load applying device 110 and is fixed to the load applying device 110. Mount specimen 10 on 123.

Subsequently, the load applying device 110 is operated to apply a tensile load to the upper jig 121 at a constant speed and force. In this case, the upper jig 121 is vertically raised to pull up the load applying plate 124 to test the specimen ( The coating film 12 of 10 is separated from the substrate 11.

In the evaluation, it is possible to evaluate the adhesion of the coating film 12 by confirming the magnitude of the tensile load applied to the specimen 10 through the load applying device 110, and as an external factor other than the adhesion of the coating film 12. The evaluation is carried out very quickly to reduce the impact.

Referring to the result of FIG. 7, the Y-axis represents the tensile load (N) applied during evaluation, until the coating film 12 is separated from the substrate 11 while applying the tensile load to the specimen 10 during evaluation. This will increase the tensile load.

In addition, the tensile load when the coating film 12 is separated from the substrate 11, that is, the maximum tensile load (eg, 397.04N), which is the peak value of the tensile load, can be measured by the load applying device (UTM) 110.

That is, the tensile load is rapidly increased until the coating film 12 is separated from the substrate 11, and the maximum tensile load is applied at the time when the coating film 12 is separated, so that the tensile load at the time of separation is applied to the load applying device. (Ie, universal testing machine (UTM)) 110, if measured by the maximum tensile load, the adhesion force can be calculated from the measured maximum tensile load.

Since the maximum tensile load is a load acting on the entire area of the bonding area B to which the load applying plate 124 is bonded, the load per unit area obtained by dividing the maximum tensile load by the area of the contact area is the characteristic of the coating film 12. And coating film adhesion, which is a property value indicating performance.

Accordingly, in the present invention, the coating film adhesion force, which shows a quantitative magnitude of the coating film adhesion force and the adhesive strength, is defined as the load per unit area, and the maximum tensile load under tension when the coating film 12 is separated from the substrate 11 is defined as the contact area. The film adhesion is calculated by dividing by.

On the other hand, in the present invention is applied to the tensile load, that is, the force to remove the coating film 12 from the substrate 11 in the state bonded to the coating film 12 of the specimen 10 directly applied to the coating film 12 In the plate 124, the load application plate is subjected to a pretreatment step of activating a functional group on the surface of the load application plate 124 by exposing the metal load application plate 124 to ultraviolet rays (UV) as described above. The adhesion between the 124 and the coating film 12 can be enhanced.

At this time, the process can be proceeded with the exposure amount of ultraviolet rays in the range of 1 ~ 100 J, and in addition to the ultraviolet treatment, the functional group on the surface of the load applying plate 124 through a known plasma treatment performed on a metal surface or the like. It can be activated, through which the adhesive force between the metal load applying plate 124 and the coating film 12 by the adhesive 14 can be increased.

In addition, instead of the metal load-applying plate 124, a material capable of exhibiting greater adhesive force between the coating film 12 and the coating film 12 than the coating film adhesion force, which is a bonding force between the coating film 12 and the substrate 11 in the specimen 10. The plate can be used as a load applying plate.

That is, a load-applying plate 124 of an alloy containing aluminum, iron, or copper may be used. For example, a metal plate such as stainless steel may be used, and the organic substrate 11 may be used.

In addition, in order to adjust the adhesive force between the coating film 12 and the load-applying plate 124 to evaluate the adhesive force, one of several kinds of adhesives 14 may be selected to evaluate the adhesive force.

At this time, epoxy resin or acrylic resin can be used as resin, the ratio with a hardening | curing agent can be 1: 9-9: 1 by weight ratio, and the hardening rate at the time of hardening can be 80% or more.

In addition, the curing temperature and time can be adjusted to vary from 10 to 200 ℃, and several minutes to several days.

The area of the adhesive region B partitioned by the coating film 12 of the evaluation specimen 10 can be an area of 0.01 mm 2 to 1 m 2, and the dissimilar material adhesive 14 is applied to the partitioned adhesive region B. It is apply | coated and the load application plate 124 is adhere | attached.

As a material of the micro-spacer 13, an organic polymer resin such as polystyrene or an inorganic filler such as ceramic may be used, and the particle size (diameter) of the micro-spacer 13 is 1. It can be set to ~ 100 ㎛, it may be used having a shape capable of maintaining a constant size, such as a rectangular parallelepiped, a spherical shape.

In addition, a spray liquid obtained by dispersing the micro-spacer 13 at a concentration of 0.00001 to 0.1 wt% in a solvent (eg, ethanol) having high volatility and not affecting the coating film 12 during the application of the micro-spacer 13. May be used, and the spray liquid in which the micro-spacer 13 is dispersed is evenly sprayed onto the surface of the coating film 12 by using a spray apparatus, and then the solvent is evaporated.

In addition, the speed of detaching the coating film 12 from the substrate 11 using the load applying device (UTM) 110, that is, the speed of raising the upper jig 121 in the load applying device 110 is 1 to 1000 mm. Evaluation can be carried out by setting within / min, the temperature of the specimen 10 during the desorption can be maintained at 10 ~ 100 ℃.

8 is a flowchart illustrating a process of evaluating coating film adhesion according to the present invention. Referring to this, the evaluation process is as follows.

The evaluation method according to the present invention is for quantifying the adhesive force of the coating film 12 according to the process parameters, for this purpose, appropriate process parameters for adhesion with the load applying plate 124 according to the coating film 12 to be evaluated first. (parameter) is set (S11).

Here, the process parameters may include the curing temperature of the dissimilar material adhesive 14, the coating area of the adhesive 14 (that is, the area of the adhesive region B) and the coating thickness, the surface treatment of the load applying plate 124, and the like. have.

Subsequently, the specimen 10 for coating adhesion evaluation is prepared, and the load applying plate 124 is attached to the coating film of the specimen 10 in accordance with the set process parameters (S12).

Then, the specimen 10 is mounted on the lower jig 123 of the coating film adhesion evaluation apparatus 100, and the load applying plate 124 attached to the coating film 12 of the specimen 10 by the adhesive 14 is placed on top. It is coupled to the jig 121 (S13).

Subsequently, the actuating part 115 of the load applying device 110 is operated to apply a tensile load to the coating film 12 of the specimen 10 through the upper jig 121 and the load applying plate 124. While gradually increasing the tensile load (S14).

In addition, during the application of the tensile load, at least a part of the coating film 12 is separated from the substrate 11 of the test piece 10 and is attached to the load applying plate 124 to check whether it is released (S15). If at least a part of the coating film 12 is attached to the load applying plate 124 and separated from the substrate 11 by checking the surface from which the coating film 12 is separated from the substrate 11, the maximum tensile load measured at the time of separation and The coating film adhesion force is calculated using the area of the adhesion region B (S16).

At this time, the coating film adhesion force is the value obtained by dividing the maximum tensile load by the area of the adhesive region (B), that is, the area of the adhesive layer 14 applied to the coating film 12 of the specimen 10 and bonded to the load applying plate 124. It can be calculated as

The area of the adhesive region B may have a tensile force, that is, a tensile load and detachment force for separating the coating film 12 from the state in which the coating film 12 and the load applying plate 124 are bonded by the adhesive 14. The coating force is calculated by dividing the maximum tensile load, which is the area in which the force acts, and the maximum tensile load, which is the detachment force, by the area of the bonding area B as the force acting area.

If the load application plate 124 is separated from the specimen 10 by applying a tensile load, the coating film 12 separated from the specimen 10 is not attached to the load application plate 124, that is, the load is applied. If at least a part of the coating film 12 is not attached to the load applying plate 124 even though the plate 124 is separated from the specimen 10, the adhesive force between the load applying plate 124 and the coating film 12 is insufficient. Since the coating film 12 is not detached from the substrate 11, the process parameters for bonding the load applying plate 124 and the coating film 12 of the specimen 10 are reset in order to increase the adhesive force (S17).

Thus, by resetting the process parameters to produce a specimen 10 in which the load-applying plate 124 is bonded and fixed to the contact area of the coating film 12, the same evaluation process for the prepared specimen 10 is carried out again to the coating film Calculate and quantify adhesion.

Hereinafter, the present invention will be described by specific examples, but the present invention is not limited by the following examples.

Example 1

After evaluating the water resistance to the specimen 10 having the coating film 12 formed on the substrate 11, the coating film adhesion strength was evaluated using the apparatus and method of the present invention, the urethane-based coating film 12 at 40 ℃ 7 days, Water resistance evaluation was performed to store and maintain each at 80 ℃ for 1 day.

In addition, after completion of the water resistance evaluation, the specimen 10 was dried at 50 ° C. for 2 days in a vacuum oven to remove moisture on the surface of the coating film 12.

Subsequently, in the dried coating film 12, the adhesion area B was partitioned with a size and a width × length = 3 mm × 3 mm, and 0.0006 wt% of a spherical micro-spacer 13 having a particle size (diameter) of 5.75 μm in ethanol. A spray solution dispersed with was prepared.

Next, the spray liquid is sprayed onto the coating film 12 of the specimen 10 and dried, and a heterogeneous material adhesive 14 mixed with a resin and a curing agent in a weight ratio of 1: 1 to the adhesive region B of the partitioned coating film as described above. Apply thinly.

Subsequently, an aluminum plate exposed to 12J of ultraviolet (UV) light as the load applying plate 124 was bonded to the adhesive region B, and the load applying plate 124 and the specimen 10 were subjected to a constant pressure by using a hand clamp. After pressing, it was cured at 70 ° C. for 2 hours in a convection oven.

The specimen 10 thus completed is mounted on the lower jig 123 of the coating film adhesion evaluation apparatus 100 of the present invention, the load applying plate 124 is coupled to the upper jig 121, and then the specimen ( 10) was applied a tensile load.

In this case, the upper jig 121 is set to rise vertically at a speed of 1000 mm / min, and at least a part of the coating film 12 when the upper jig 121 is raised to separate the load applying plate 124 from the specimen 10. Was removed from the substrate 11 of the specimen 10 and attached to the load applying plate 124.

As a result of confirming the surface of the coating film 12 of the specimen 10 and the surface of the load applying plate 124, as shown in FIG. 9, a part of the coating film 12 is formed in the adhesive region B of the surface of the coating film 12. It was confirmed that the substrate 11 was detached from the substrate 11 and adhered to the load applying plate 124.

As described above, part of the coating film 12 of the adhesive region B adheres to the load applying plate 124 and is detached to the substrate 11 of the test piece 10, and thus, the time point at which the load applying plate 124 is separated from the test piece 10. The coating film adhesion force was calculated using the maximum tensile load measured in the load application device (UTM) (110).

10 shows the load value measured by the load applying device 110 (UTM) when the coating film 12 is detached from the coating film adhesion evaluation apparatus 100 as described above after evaluating water resistance at 80 ° C. in a day. It is shown.

As can be seen in Figure 10, in Example 1 it was confirmed that the maximum tensile load was 8.8N to detach the coating film 12 for the contact area of 0.09cm 2 area, the coating film adhesion force was 97.78N / ㎠.

Example 2

The coating film adhesion according to the anti-cream cream evaluation condition was quantified and evaluated for the specimen 10 having the coating film 12 formed on the substrate 11.

At this time, after evaluating the sunscreen cream resistance of the coating film 12, the adhesion of the coating film 12 was evaluated using the apparatus and method of the present invention, and the sunscreen cream evaluation was performed by applying sunscreen to the surface of the urethane-based coating film 12. It was.

When evaluating the anti-cream cream, the sunscreen was applied to the surface of the coating film 12 of the specimen 10 and cured. After the anti-cream cream evaluation was completed, the surface of the coating film 12 was washed with a neutral detergent. 10) was dried at 50 ° C. for 2 days to remove moisture on the surface of the coating film 12.

In addition, in the dried coating film 12, the adhesive region B was partitioned with a size and a width × length = 3 mm × 3 mm, and 0.0006 wt. Of a spherical micro-spacer 13 having a particle size (diameter) of 5.75 µm in ethanol. A spray solution dispersed in% was prepared.

Next, the spray liquid is sprayed onto the coating film 12 of the specimen 10 and dried, and a thin material adhesive 14 mixed with a resin and a curing agent in a weight ratio of 1: 1 is applied to the divided adhesive region B partitioned as described above. It was.

Subsequently, an aluminum plate exposed to 12J of ultraviolet (UV) light as the load applying plate 124 was bonded to the adhesive region B, and the load applying plate 124 and the specimen 10 were applied at a constant pressure using a hand clamp. After pressing, it was cured at 70 ° C. for 2 hours in a convection oven.

The specimen 10 thus completed is mounted on the lower jig 123 of the coating film adhesion evaluation apparatus 100 of the present invention, the load applying plate 124 is coupled to the upper jig 121, and then the specimen ( 10) was applied a tensile load.

In this case, the upper jig 121 is set to rise vertically at a speed of 1000 mm / min, and at least a part of the coating film 12 when the upper jig 121 is raised to separate the load applying plate 124 from the specimen 10. Was removed from the substrate 11 of the specimen 10 and attached to the load applying plate 124.

As a result of confirming the surface of the coating film 12 of the specimen 10 and the surface of the load application plate 124, a part of the coating film 12 is bonded to the substrate 11 of the specimen 10 in the adhesive region B of the surface of the coating film 12. It was confirmed that it was attached to the load-applying plate 124 by detaching from).

As described above, part of the coating film 12 of the adhesive region B adheres to the load applying plate 124 and is detached to the substrate 11 of the test piece 10, and thus, the time point at which the load applying plate 124 is separated from the test piece 10. The coating film adhesion force was calculated using the maximum tensile load measured in the load application device (UTM) (110).

FIG. 11 shows that the sunscreen is applied to the surface of the coating film 12 in Example 2, and then cured at 100 ° C. for 1 day, followed by washing and drying, thereby detaching the coating film 12 from the coating film adhesion evaluation apparatus 100 as described above. At this time, the load value measured by the load application device (UTM) 110 is shown.

As can be seen in Figure 11, in Example 2 it was confirmed that the maximum tensile load was 15.4N to detach the coating film 12 for the contact area of 0.09cm 2 area, the coating film adhesion force was 171.1N / ㎠.

Example 3

The adhesion of the coating film 12 was quantified and evaluated for the specimen 10 having the coating film 12 formed on the substrate 11.

At this time, the adhesive force of the coating film 12 was evaluated using the apparatus and method of the present invention, and the adhesive force was compared and evaluated according to the content of CPO (Chlorinated polyolefin) which gives adhesiveness to the polypropylene coating film 12.

At this time, the ratio was compared by acryl (acryl): CPO content 1: 3, 2: 2, 3: 1 by weight ratio, respectively, the same as in Example 2 for the coating film 12 of the specimen 10 After the resistance cream evaluation was carried out by the method, the adhesion of the coating film 12 was measured.

In addition, after the evaluation of the anti-cream cream resistance, the adhesive region (B) is partitioned in the dried coating film 12 with the size and area of width × length = 3 mm × 3 mm, and the spherical micro-spacer having a particle size (diameter) of 5.75 μm in ethanol A spray solution was prepared in which 13) was dispersed at 0.0006 wt%.

Next, the spray liquid is sprayed onto the coating film 12 of the specimen 10 and dried, and a thin material adhesive 14 mixed with a resin and a curing agent in a weight ratio of 1: 1 is applied to the divided adhesive region B partitioned as described above. It was.

Subsequently, an aluminum plate exposed to 12J of ultraviolet rays (UV) as the load applying plate 124 was bonded to the adhesive region B, and the load applying plate 124 and the specimen 10 were subjected to a constant pressure by using a hand clamp. After pressing, it was cured at 70 ° C. for 2 hours in a convection oven.

The specimen 10 thus completed is mounted on the lower jig 123 of the coating film adhesion evaluation apparatus 100 of the present invention, the load applying plate 124 is coupled to the upper jig 121, and then the specimen ( 10) was applied a tensile load.

In this case, the upper jig 121 is set to rise vertically at a speed of 1000 mm / min, and at least a part of the coating film 12 when the upper jig 121 is raised to separate the load applying plate 124 from the specimen 10. Was removed from the substrate 11 of the specimen 10 and attached to the load applying plate 124.

As a result of confirming the surface of the coating film 12 of the specimen (acryl: CPO = 3: 1) 10 and the surface of the load application plate 124, a part of the coating film 12 in the adhesive region B on the surface of the coating film 12 was observed. Was removed from the substrate 11 of the specimen 10 and attached to the load applying plate 124.

As described above, part of the coating film 12 of the adhesive region B adheres to the load applying plate 124 and is detached to the substrate 11 of the test piece 10, and thus, the time point at which the load applying plate 124 is separated from the test piece 10. The coating film adhesion force was calculated using the maximum tensile load measured in the load application device (UTM) (110).

12 is applied to the surface of the coating film 12 of the specimen (acrylic: CPO = 3: 1) (10) in Example 3 and then cured at 100 ℃ for 1 day, then washed and dried after coating film as described above When the coating film 12 is detached from the adhesion evaluation apparatus 100, the load value measured by the load application apparatus (UTM) 110 is shown.

As can be seen in Figure 12, in Example 3 it was confirmed that the maximum tensile load was 75.9N to detach the coating film 12 for the contact area of the area 0.09cm 2, the coating film adhesion force was 843.3N / ㎠.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are provided. Also included in the scope of the present invention.

10: specimen 11: substrate
12: coating film 13: spacer
14 adhesive 100 coating film adhesion evaluation device
110: load application device 111: main body
112: Table 113: Guide frame
114: drive device 115: operating part (cross head)
116: drive motor 117: gearbox
118: ball screw 120: mounting portion
121: upper jig 122: connection ring
123: lower jig 124: load application plate
125: coupling groove 126: fastening mechanism
127: bolt member 128: pressure member
130: control unit 131: computer
132 monitor B: adhesive area

Claims (12)

A load-applying device having an operating part which is operated to move up and down by the driving device in the main body, and applying a tensile load to act on the coating film of the specimen as the operating part is operated;
An upper jig installed in the operating part and to which a load applying plate is coupled; And
A lower jig installed on a table of the load application device, the lower jig on which a specimen in a state where the load application plate is adhered to a surface of a coating film formed on a substrate is mounted;
The load application device
As the operating part is operated and raised, a tensile load is applied to the coating film of the specimen through the upper jig and the load applying plate
And the tensile load when at least a portion of the coating film adhered to the load-applying plate by the tensile load can be measured when separated from the substrate of the specimen.
The method according to claim 1,
The upper jig to which the load application plate is coupled and the lower jig to which the specimen is mounted are installed so that the load application plate and the specimen may be arranged to cross at right angles to each other.
Preparing a specimen having a coating film formed on a surface of the substrate;
Adhering a load-applying plate to the coating film of the specimen with an adhesive;
Mounting the specimen on a lower jig and coupling the load applying plate to an upper jig;
In the main body of the load-applying device to operate the operating part to move up and down by the driving device, the operation of the test piece through the upper jig and the load applying plate installed in the operating part as the operating part is operated by the driving device to raise Allowing a tensile load to be applied to the coating film;
Gradually increasing the applied load; And
While increasing the tensile load, a maximum tensile load is measured when at least a portion of the coating film of the specimen bonded to the load-applying plate by the tensile load is separated from the substrate, and the coating film adhesion force is calculated from the measured maximum tensile load. Coating film adhesion evaluation method comprising a.
The method according to claim 3,
In the step of adhering the load application plate to the coating film of the specimen, the coating film adhesion evaluation method characterized in that the load application plate is bonded to the coating film of the specimen so that the load application plate is disposed to cross at right angles to the specimen.
The method according to claim 3,
In the step of manufacturing the specimen to partition the adhesive area of a predetermined area of the coating film of the specimen to be separated from the peripheral region,
And applying the adhesive to the adhesive region in the step of adhering the load-applying plate to the coating film of the specimen so that the load-applying plate is adhered to the adhesive region by the adhesive.
The method according to claim 5,
And calculating the coating film adhesion force by a load value per unit area obtained by dividing the measured maximum tensile load by the area of the adhesive region in the calculating of the coating film adhesion force.
The method according to claim 3,
And a pretreatment step of activating a functional group on the surface of the load-applying plate by exposing the surface of the load-applying plate to ultraviolet rays or plasma treatment.
The method according to claim 3,
Distributing and fixing a spacer having a predetermined particle size on the surface of the coating film of the specimen, and after applying the adhesive to the surface of the coating film to which the spacer is fixed, the coating film adhesion evaluation, characterized in that for applying a load applying plate Way.
The method according to claim 8,
In the fixing of the spacer, a micro-spacer having a particle size of micrometer scale is added to the volatile solvent and dispersed, and the spray liquid having the micro-spacer dispersed in the volatile solvent is evenly sprayed on the surface of the coating film of the specimen. After that, the volatile solvent is evaporated.
The method according to claim 9,
The micro-spacer has a particle size of 1 ~ 100 ㎛, the coating film adhesion evaluation method characterized in that the dispersion of the micro-spacer in a concentration of 0.00001 ~ 0.1 wt% in the volatile solvent.
The method according to claim 3,
A method for evaluating coating film adhesion, characterized by using an adhesive including a hardener in an epoxy resin or an acrylic resin as the adhesive.
The method according to claim 3,
Check that at least a part of the coating film of the specimen is attached to the load application plate after being separated from the substrate, and calculating the coating film adhesion force from the measured maximum tensile load when at least a part of the coating film of the specimen is attached to the load application plate. A coating film adhesion evaluation method characterized by the above-mentioned.

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