JP2014038040A - Anti-scratch performance evaluating method and evaluating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-scratch performance evaluating method and evaluating apparatus enabling the anti-scratch performance of an evaluation object when it is scratched while a pressing load is increased to be objectively and quantitatively evaluated and making possible accurate evaluation of the anti-scratch performance, with the extent of the scratch thereby made into consideration.SOLUTION: An anti-scratch performance evaluating method for a resin-made evaluation object P whose surface is textured comprises: a scratch making step of making a linear scratch K by scanning a chip 22 over a prescribed distance X while increasing a pressing load; a scratch luminosity measuring step of measuring luminosity Ln of light reflected from the scratch K irradiated with light; an evaluated value calculating step of calculating an evaluated luminosity value of the scratch K; a scratch making initial load calculating step of calculating the scratch making initial load; and an evaluation step of evaluating the anti-scratch performance of the evaluation object P on the basis of the evaluated luminosity value and the scratch making initial load.

Description

  The present invention relates to a scratch resistance evaluation method and an evaluation apparatus for an evaluation object made of a resin whose surface is textured.

  As an evaluation method for evaluating the scratch resistance (scratch resistance) of an evaluation object made of resin, for example, Patent Document 1 describes a technique related to a Gakushoku type dyeing wear fastness test based on JIS L0849. . In the technique described in Patent Document 1, a test piece of a surface-textured textured product having a predetermined shape is subjected to a test under a predetermined condition using a friction tester type II (Gakushin type) described in JIS L0849. The degree of discoloration is measured with a spectroscopic color difference meter to evaluate the scratch resistance (scratch resistance) of the test piece.

  Further, as a surface inspection apparatus and a surface inspection method for inspecting scratches on a resin-made object whose surface is textured, for example, in Patent Document 2, only light that has passed through a rectangular slit is used as a light detection means. A technique for guiding and detecting the surface state of the appearance of the object to be measured (such as whitening scratches and shine cracks) from the brightness detected by the light detection means is described. The technique described in Patent Document 2 quantifies the surface state of the appearance of the measurement object strictly and with high accuracy by limiting the light detection range of the reflected light on the surface of the measurement object with a slit.

JP 2011-79924 A (refer to paragraph “0103” in particular) JP 2000-283931 A (refer to FIG. 8 in particular)

  Since the technique described in Patent Document 1 described above is to apply a white cotton cloth fixed to a friction element while applying a predetermined load using a friction tester type II (Gakushin type) to a test piece, It was not possible to evaluate the scratch resistance of the evaluation object when the specimen was damaged while increasing the load. In addition, since the technique described in Patent Document 1 measures the degree of discoloration of the embossed surface, it is impossible to evaluate how the scratches start to be formed, and in which longitudinal direction the scratches are It was not possible to evaluate how it was formed. Therefore, it is possible to objectively and quantitatively evaluate the scratch resistance when the test piece is scratched while increasing the load, how the scratch starts to be formed, and how the scratch is in the longitudinal direction. There was room for improvement from the viewpoint of enabling accurate evaluation of scratch resistance considering whether it was formed. In particular, when evaluating the scratch resistance of an evaluation object made of resin that has been subjected to graining processing, the unevenness due to graining process tends to hinder the objective and quantitative evaluation by visual inspection. In addition, establishment of a quantitative evaluation method has been desired.

  In addition, since the technique described in Patent Document 2 is for inspecting scratches already formed on the object to be measured, it is not possible to evaluate the scratch resistance of the object to be measured. Since the slit is scanned in a direction perpendicular to the longitudinal direction of the scratch, it is not possible to inspect how the scratch starts to be formed as in the technique described in Patent Document 1 described above. It was not possible to inspect how it was formed in the longitudinal direction.

  The object of the present invention is to enable an objective and quantitative evaluation of scratch resistance when an object to be evaluated is scratched while increasing the pressing load. An object of the present invention is to provide a scratch resistance evaluation method and an evaluation apparatus capable of evaluating the property.

  A first invention is a scratch resistance evaluation method for an evaluation object made of a resin whose surface has been subjected to embossing, and the chip is scanned a predetermined distance while increasing the pressing load on the surface of the evaluation object. A wound creating step for creating a straight wound, a wound lightness measuring step for measuring the brightness of light reflected by irradiating the wound with light at a predetermined measurement pitch along the longitudinal direction of the wound, and An evaluation value calculation step for calculating the lightness evaluation value of the scratch based on the lightness measured for each measurement pitch, a scratch creation start load calculation step for calculating a scratch creation start load at which the scratch actually started to be created, An evaluation step of evaluating the scratch resistance of the evaluation object based on the brightness evaluation value and the scratch creation start load.

  According to the above configuration, it is possible to objectively and quantitatively evaluate the scratch resistance when the evaluation target is scratched while increasing the pressing load, and how the scratch is formed, that is, how the scratch is formed. It is possible to evaluate the scratch resistance with high accuracy in consideration of whether the scratch starts to be formed or how the scratch is formed in the longitudinal direction. Therefore, it is a resin material that has been subjected to embossing used for interior parts of automobiles such as automobiles and trucks, office automation equipment, home appliances, housing equipment, and household goods. It is possible to select a resin material having a good balance of scratching properties.

  According to a second invention, in the scratch resistance evaluation method according to the first invention, light is irradiated to the surface of the evaluation object before the scratch is created or the surface of the evaluation object on which the scratch is not created. A surface brightness measurement step of measuring the surface brightness of the received light for each of the measurement pitches, and the evaluation value calculating step includes averaging the surface brightness based on the surface brightness measured for each of the measurement pitches And calculating an integrated value of the rate of change in brightness obtained by dividing the difference between the average value and the brightness of the scratch measured at each measurement pitch, and calculating the integrated value by the predetermined distance. Or the reciprocal of the value obtained by dividing the integrated value by the predetermined distance is calculated as the brightness evaluation value.

  According to the above configuration, using the brightness evaluation value in consideration of the surface state of the evaluation object before creating the scratch or the surface state of the evaluation object on which the scratch is not formed, that is, the roughness of the embossing is the lightness of the scratch. Using the lightness evaluation value in consideration of the influence on the measurement value, the scratch resistance of the evaluation object can be evaluated more accurately.

  According to a third aspect of the present invention, in the scratch resistance evaluation method of the first or second aspect of the invention, the flaw creation step creates a straight whitening flaw on the surface of the evaluation object, and the flaw lightness measurement step comprises The brightness of the light received by irradiating the whitening scratch with light in a dark field is measured for each measurement pitch.

  According to the above configuration, the stress whitening phenomenon tends to occur in the scratches themselves, and the brightness of the whitening scratches that have a strong tendency to reflect incident light from an oblique angle as diffused light can be accurately detected from the light received by irradiating the dark field. It becomes possible to detect well. Thereby, it is possible to evaluate the scratch resistance with high accuracy for the whitening scratch.

  According to a fourth aspect of the present invention, in the scratch resistance evaluation method of the first or second aspect of the invention, the flaw creation step creates a linear gloss flaw on the surface of the evaluation object, and the flaw lightness measurement step comprises The brightness of the received light by irradiating the glossy scratch with bright field is measured for each measurement pitch.

  According to the above configuration, the roughness of the surface of the evaluation object tends to be flattened due to scratches, and the brightness of glossy scratches that tend to reflect incident light as it is is accurately measured from light received by bright field irradiation. It becomes possible to detect well. Thereby, it is possible to accurately evaluate the scratch resistance with respect to the glossy scratch.

  A fifth invention is a scratch resistance evaluation apparatus used in the scratch resistance evaluation method according to any one of the first to fourth inventions, wherein the evaluation is performed by scanning the chip for a predetermined distance while increasing the pressing load. Scratch creating means for creating a linear scratch on the surface of the object, and a brightness for measuring the brightness of light reflected by irradiating the scratch from the irradiation unit at each measurement pitch along the longitudinal direction of the scratch Measuring means, calculation means for calculating the scratch creation start load and the brightness evaluation value, and display means for displaying the scratch creation start load and the brightness evaluation value.

  According to the above configuration, the scratch creation means, the brightness measurement means, and the calculation means can easily acquire and calculate data used in the evaluation method, and can withstand resistance from the scratch creation start load and the brightness evaluation value displayed on the display means. It is possible to easily evaluate the damage property.

  According to a sixth aspect of the present invention, in the scratch resistance evaluation apparatus of the fifth aspect, the lightness measuring means transmits light reflected by irradiating light from the irradiation section through a slit elongated in the short direction of the scratch. Then, the lightness of the scratch is measured at each measurement pitch.

  According to the above configuration, it becomes possible to limit the detection range of the light reflected from the scratch by the elongated slit in the short direction of the scratch, and to measure the lightness of the scratch with the measurement pitch subdivided in the longitudinal direction of the scratch, It is possible to detect the lightness of the wound while quantifying it with high accuracy.

The block diagram which shows the whole structure of the damage resistance evaluation apparatus which concerns on this invention Perspective view showing the detailed structure of the wound creating device Perspective view showing the detailed structure of the brightness measuring device Explanatory drawing explaining the specific content of the scratch resistance evaluation method according to the present invention Graph showing the measurement results of scratch lightness and surface lightness Graph showing the calculation result of brightness change rate Graph showing the correlation between scratch creation start load and brightness evaluation value

[Overall configuration of the scratch resistance evaluation apparatus]
The overall configuration of the scratch resistance evaluation apparatus 1 will be described with reference to FIGS. As shown in FIG. 1, the scratch resistance evaluation apparatus 1 measures the lightness of a scratch creating apparatus 2 that creates a linear scratch K on the surface of the evaluation object P and the scratch K created by the scratch creating apparatus 2. The brightness measurement device 3, the control device 4 that controls the brightness measurement device 3, the display unit 5 that displays data such as the brightness measurement value M and the brightness evaluation value H calculated by the control device 4, and the control device 4 And an input unit 6 for inputting various control commands.

  The wound creation device 2 includes a table 21 on which the evaluation object P is placed and fixed and supported, a chip 22 that can be moved relative to the table 21 in the longitudinal direction of the evaluation object P, and the chip 22 as the evaluation object P. A chip moving mechanism 23 that presses against the table 21 and moves relative to the table 21; a chip control unit 24 that controls the chip moving mechanism 23; and an input setting unit 25 that inputs operation commands and sets operating conditions for the chip moving mechanism 23. And an output display unit 26 for displaying the operating conditions and operating state of the tip moving mechanism 23. The scratch creating apparatus 2 of the present embodiment is integrated so that each component described above is attached to an apparatus main body (not shown).

  As shown in FIG. 2, the chip 22 is detachably held by a holding part 23A of the chip moving mechanism 23, and by operating the holding part 23A, a chip having a different shape or the like, for example, a chip for creating a whitening wound. It can be replaced with a chip for creating a glossy flaw, a chip for creating a scaly flaw, a chip for creating a cut flaw, and the like. The tip moving mechanism 23 applies a load in a direction in which the holding unit 23A is pushed vertically toward the surface of the evaluation target P, and relatively moves the holding unit 23A in the longitudinal direction of the evaluation target P to apply the load. The surface 22 of the evaluation object P is scratched by the tip 22 that moves while moving. The wound K is a wound having an inclination that increases in depth and width from one end side in the longitudinal direction of the evaluation object P toward the other end side. Although not shown, the table 21 includes a positioning mechanism that positions the evaluation object P at a predetermined position and a fixing mechanism that fixes the evaluation object P placed on the table 21 at a predetermined position. An operator who operates the flaw creating apparatus 2 uses these positioning mechanism and fixing mechanism to position and fix the evaluation object P at a predetermined position on the table 21 as a preparatory work before the scratching work starts.

  As shown in FIG. 1, the operator operates the flaw creation device 2 by an input setting unit 25 connected to the chip control unit 24. In the input setting unit 25, the load application conditions such as the magnitude of the load to be applied to the evaluation target P and the tip moving distance X for scanning the tip 22 while applying the load to the evaluation target P can be input manually. . The setting of the load size in the input setting unit 25 is, for example, a mode in which the load is increased from the initial load to the maximum load in proportion to the chip movement distance X, or the increase rate increases as the chip movement distance X increases, for example. As described above, various forms such as a form for increasing the load from the initial load to the maximum load can be set, and the above-described initial load and the maximum load can be arbitrarily set. The chip control unit 24 controls the chip moving mechanism 23 so as to scratch the evaluation object P under these load application conditions.

  The input setting unit 25 is equipped with various switches not shown. The worker who performs the scratching operation operates the start switch of the input setting unit 25 after performing the above-described preparatory work, so that the chip control unit 24 inserts the chip so that the load addition condition set by the input setting unit 25 is satisfied. The moving mechanism 23 is controlled to scratch the surface of the evaluation object P. Note that an output display unit 26 is connected to the chip control unit 24, and the load application conditions set by the input setting unit 25 and the operation state of the chip moving mechanism 23 such as during the damage work and completion of the damage work are output. Displayed appropriately on the display unit 26.

  The lightness measuring device 3 includes a movable table 31 on which the evaluation object P is placed and fixed and supported, an irradiation unit A that irradiates light onto the surface of the evaluation object P supported by the mobile table 31, and an irradiation unit. It is comprised with the optical microscope provided with the detection part B which detects the light which irradiated and reflected the surface of the evaluation target P by A.

  As shown in FIG. 3, the mobile table 31 includes a base 31A, a mounting base 31B on which the evaluation target P is placed, a slide member 31C that slidably supports the mounting base 31B on the base 31A, An actuator 31D that slides the mounting table 31B with respect to the base 31A. The actuator 31D is fixed to the base 31A, and is connected to the mounting table 31B via a feed screw mechanism or the like (not shown). Although not shown, the mounting table 31B includes a positioning mechanism that positions the evaluation object P at a predetermined position and a fixing mechanism that fixes the evaluation object P mounted on the mounting table 31B at a predetermined position. An operator who operates the lightness measuring apparatus 3 uses these positioning mechanisms and fixing mechanisms to position and fix the evaluation object P at a predetermined position on the mounting table 31B as a preparatory work before starting the lightness measuring work.

  As shown in FIG. 1, the irradiation unit A includes a light source 32 configured by a halogen lamp, a lens 33 that changes light from the light source 32 to parallel light, and parallel light from the lens 33 for dark field illumination or bright light. The switching mechanism 34 that switches to the field illumination and irradiates the evaluation object P, and the annular dark field illumination is bent while the switching mechanism 34 is switched to the dark field illumination, and the surface of the evaluation object P is irradiated from the oblique direction. A dark field lens 35 that emits the light A1. By switching the switching mechanism 34 to dark field illumination, the light from the lens 33 can be irradiated as irradiation light A1 having an oblique irradiation angle (for example, 45 °) with respect to the surface of the evaluation object P. By switching 35 to bright field illumination, light from the lens 33 can be irradiated as irradiation light A2 having an irradiation angle perpendicular to the surface of the evaluation object P. The switching mechanism 34 may be configured as a manual switching type that is switched to dark field illumination or bright field illumination by manual operation by an operator, or automatically by an output from the control device 4 depending on the type of the scratch K of the evaluation object P or the like. Alternatively, it may be configured to automatically switch to dark field illumination or bright field illumination.

  The detection unit B includes an objective lens 36 disposed opposite to the surface of the evaluation object P, and a y filter 37, a slit member 38, and a light receiving element 39 disposed in order from the lower side on the optical axis B1 of the objective lens 36. . The y filter 37 is a filter having a pass band in the green wavelength range, and the y filter 37 allows light in the green wavelength range to pass mainly instead of the red and blue wavelength ranges. The light that has passed through the y filter 37 passes through a slit 38 </ b> A formed in the slit member 38. The light that has passed through the slit 38A is received by the light receiving element 39. The slit 38A is formed of a rectangular slit that is elongated in the short direction perpendicular to the longitudinal direction of the wound K formed on the surface of the evaluation object P (see FIG. 3). Although not shown, the slit member 38 is configured to be switchable so that a plurality of slits 38A having different sizes can be switched manually or automatically.

  The control device 4 includes a measurement unit 41 that measures the brightness based on the output signal of the light receiving element 39, a calculation unit 42 that performs arithmetic processing on the brightness measured by the measurement unit 41, and the brightness and calculation measured by the measurement unit 41. An output unit 43 that outputs the calculation data calculated by the unit 42 to the display unit 5 such as a display, and a control unit 44 that supplies power to the light source 32 of the illumination unit A and controls the actuator 31D of the mobile table 31. With.

  The operator operates the brightness measuring device 3 with the input unit 6 connected to the control device 4. The input unit 6 includes a keyboard, switches, and the like. In the input unit 6, the load addition condition set by the input setting unit 25 of the flaw creation device 2 and the lightness measurement condition by the lightness measurement device 3 can be input manually. In the input unit 6, as a lightness measurement condition, a scanning distance for scanning the irradiation unit A and the detection unit B with respect to the evaluation object P and a lightness measurement pitch a for actually measuring the lightness within the scanning distance are set. In the present embodiment, the scanning distance of the lightness measurement condition is associated with the chip movement distance X of the load addition condition. If the chip movement distance X of the load addition condition is input by the input unit 6, the input chip movement distance X is input. Is automatically set as the scanning distance. In the following description, the scanning distance will be described with the same symbol X as the tip moving distance. The control unit 44 outputs to the actuator 31D via the driver 45 so that the evaluation object P placed on the placement table 31B moves relative to the irradiation unit A and the detection unit B under the above-described brightness measurement conditions. To control.

  The control unit 44 is connected to the measurement unit 41 and is controlled so that the above-described brightness measurement condition and the measurement timing of the brightness by the measurement unit 41 are synchronized. That is, the control unit 44 controls the measurement unit 41 so that the measurement unit 41 starts measuring the brightness from the output signal of the light receiving element 39 in accordance with the movement start timing of the evaluation object P, and is set as the brightness measurement condition. The measurement unit 41 controls the measurement unit 41 so that the measurement unit 41 measures the lightness from the output signal of the light receiving element 39 for each measurement pitch a, and the measurement unit 41 outputs the output of the light receiving element 39 in accordance with the movement end timing of the evaluation object P. The measurement unit 41 is controlled to end the measurement of the brightness from the signal. The brightness data measured by the measurement unit 41 is digitized by the A / D converter by the measurement unit 41 and then output to the calculation unit 42 and also output to the output unit 43 and displayed on the display unit 5. The The calculation unit 42 acquires brightness data of the evaluation object P from the measurement unit 41 and executes various calculation processes described later. The calculation processing result by the calculation unit 42 is output to the output unit 43 and displayed on the display unit 5.

[Specific contents of the scratch resistance evaluation method]
The specific content of the scratch resistance evaluation method according to the present invention will be described with reference to FIG. 4 along with the operation procedure of the scratch resistance evaluation apparatus 1. The operation of the scratch resistance evaluation apparatus 1 is mainly divided into an operation of the scratch creating apparatus 2 and an operation of the brightness measuring apparatus 3. First, as a preparatory work for the operation of the scratch creating apparatus 2, a belt-plate-shaped resin material processed into a predetermined shape is prepared as the evaluation object P, and the evaluation object P is tabled using the positioning mechanism and the fixing mechanism described above. Positioning and fixing at a predetermined position on 21. Before and after this preparatory work, the input setting unit 25 is operated to set the load application condition, that is, the magnitude of the load to be applied to the evaluation object P and the tip movement distance X for scanning the tip 22. Then, as shown in the “scratch creation step” in FIG. 4, by operating the start switch of the input setting unit 25, the surface of the evaluation object P is scratched under the load addition condition set by the input setting unit 25. . In FIG. 4, as an example of setting the magnitude of the load in the load addition condition, the load is increased from the initial load (0) to the maximum load (F) in proportion to the tip moving distance X. Is shown.

  When the “scratch creation step” is completed, first, as a preparatory work for the operation of the brightness measuring device 3, the evaluation object P on which the scratch K is created is removed from the scratch creation device 2, and the positioning mechanism and the fixing mechanism described above are used. The evaluation object P is positioned and fixed at a predetermined position on the mounting table 31B. Before and after this preparatory work, the input unit 6 is operated to set the lightness measurement conditions, that is, the tip movement distance X (scanning distance X) as a load application condition and the measurement pitch a as a lightness measurement condition. Then, as shown in the “scratch lightness measurement step” in FIG. 4, scratches created on the surface of the evaluation object P with the scanning distance X and the measurement pitch a set by the input unit 6 by operating the input unit 6. K lightness L1, L2, L3... Ln (hereinafter referred to as scratch lightness) is measured. The “lightness” in the present embodiment is the lightness expressed in the CIE-L * a * b * color system, and before actually measuring the lightness, the white reference plate (Y: 95.76). ) To calibrate.

  Separately from the scratch creation step and the scratch brightness measurement step, the surface brightness (hereinafter referred to as surface brightness) of the evaluation object P before the scratch K is created in the scratch creation step is measured. The operation procedure of the lightness measuring apparatus 3 is the same as the operation procedure described in the scratch lightness measurement step, and an evaluation object P on which no scratch K is created is positioned and fixed at a predetermined position on the mounting table 31B. Then, as shown in the “surface brightness measurement step” in FIG. 4, by operating the input unit 6, the surface brightness S 1, S 2, and S 2 of the evaluation object P at the scanning distance X and the measurement pitch a set by the input unit 6. S3... Sn is measured.

  In this case, it may be configured to measure the surface brightness of the evaluation object P at the same position as the position where the scratch K is applied in the scratch creation step, and the evaluation object at a position different from the position where the scratch K is applied in the scratch creation step. You may comprise so that the surface brightness of P may be measured. If it is configured to measure the surface brightness of the evaluation object P at the same position as the position where the scratch K is applied in the scratch creation step, it is possible to save time and trouble of positioning the evaluation object P and to accurately evaluate the scratch resistance. There are advantages. Further, it is possible to measure the surface brightness of the surface of the part of the evaluation object P where the scratch K is not created after the scratch creating step is completed, not before the scratch K is created in the scratch creating step. Good. In this case, in the surface lightness measurement step, the evaluation object P may be positioned and fixed at a position different from the position where the evaluation object P is positioned and fixed in the scratch lightness measurement step.

  Next, the calculation unit 42 performs the following “evaluation value calculation step” using the surface lightness Sn measured in the surface lightness measurement step and the surface lightness Sn measured in the surface lightness measurement step.

  First, the calculation unit 42 calculates the average value L0 of the surface brightness Sn measured in the surface brightness measurement step according to the following “Equation 1”.

  Next, the calculation unit 42 calculates the lightness change rates M1, M2,... Mn according to the following “Formula 2” from the calculated average value L0 of the surface lightness and the lightness Ln measured in the lightness measurement step. Calculate. The “lightness change rate Mn” indicates how much the respective lightness L1... Ln measured in the lightness measurement step has changed with respect to the average value L0.

  Next, the calculation unit 42 calculates a brightness evaluation value H from the calculated brightness change rate Mn and the scanning distance X according to the following “Equation 3”. Thereby, the brightness evaluation value H, which is one parameter of the scratch resistance evaluation, is automatically calculated. The “lightness evaluation value H” is set by the inventor after trial and error as an index for evaluating the conspicuousness of the entire wound K, and the integrated value of the lightness change rate Mn is divided by the scanning distance X. The reciprocal of the value is calculated. The brightness evaluation value H is not calculated by calculating the reciprocal of the value obtained by dividing the integrated value of the brightness change rate Mn by the scanning distance X, but may be a value obtained by dividing the integrated value of the brightness change rate Mn by the scanning distance X. . When the reciprocal is calculated, it can be evaluated that the larger the calculated lightness change rate is, the less noticeable the entire wound K is (ie, the smaller the value is, the more conspicuous) is. It can be evaluated that the entire wound K is more conspicuous (the smaller it is, the less conspicuous it is).

  The calculation of the scratch start load, which is the other parameter of the scratch resistance evaluation, is performed as follows. As shown in the “scratch creation start load calculation step” in FIG. 4, first, from the start point X0 at which the creation of the scratch K is started to the scratch creation start location where it can be determined that the creation of the scratch K has actually started visually. The distance Xa is measured using a measuring tool or the like. Then, from this measurement distance Xa, the magnitude of the load applied to the evaluation object P at the scratch creation start location, that is, the scratch creation start load Fa is calculated using the following “Formula 4”. In this case, the flaw creation start load Fa may be calculated manually and the calculation result may be manually input from the input unit 6 to the calculation unit 42. The measurement distance Xa is manually input from the input unit 6. The calculation unit 42 may be configured to automatically calculate the flaw creation start load Fa. Note that F in “Expression 4” is the maximum load under the load addition condition.

  In this case, the calculation unit 42 may be configured to automatically calculate the wound creation start load Fa using the wound lightness L1... Ln measured in the wound lightness measurement step. Specifically, for example, a threshold value of the lightness level that can be determined that the creation of the wound K has been started is set in advance in the calculation unit 42, and the calculation unit 42 is a portion where the lightness level L1... Ln exceeds the threshold value. Is automatically specified as a scratch creation start location, and the distance Xa from the start point X0 to the scratch creation start location is automatically calculated backward from the measurement pitch a, and the scratch creation start load Fa is calculated using the above-described "Expression 4". You may comprise so that it may calculate automatically. Further, the calculation unit 42 may be configured to automatically calculate the flaw creation start load Fa using the brightness change rate Mn measured in the evaluation value calculation step. Specifically, for example, a threshold value of the lightness change rate Mn that can be determined that the creation of the scratch K has been started is set in advance in the calculation unit 42, and the calculation unit 42 determines a location where the lightness change rate Mn exceeds the threshold value. Automatically identified as a scratch creation start location, automatically calculates the distance Xa from the start point X0 to the scratch creation start location from the measurement pitch a, and automatically calculates the scratch creation start load Fa using the above-described “Equation 4”. You may comprise so that it may calculate automatically.

  As shown in “Evaluation step” in FIG. 4, the brightness evaluation value H calculated in the evaluation value calculation step and the scratch creation start load Fa calculated in the scratch creation start load calculation step are output to the output unit 43. It is displayed on the display unit 5 as a table or a graph. Then, the worker evaluates the scratch resistance of the evaluation object P from the table or graph displayed on the display unit 5.

Using the scratch resistance evaluation method described above, the scratch resistance of a plurality of evaluation objects P1 to P4 was evaluated under the following conditions. The plurality of evaluation objects P <b> 1 to P <b> 4 are obtained by applying different embossing to the surface of a black resin material that does not contain talc, and the material of the resin material is the same made of polypropylene. In addition, a present Example shows the evaluation example at the time of creating the whitening wound on the surface of several evaluation object P1-P4, and "the chip | tip for whitening wound preparation" is used as the chip | tip 22 of the wound preparation apparatus 2. FIG. In the state where the switching mechanism 34 of the lightness measuring device 3 is switched to “dark field illumination” and the size of the slit 38A of the lightness measuring device 3 is set to “15 mm × 0.5 mm”, the following [1] and [2] ] Was evaluated for scratch resistance under the conditions. In the case of whitening scratches (scratches, cutting scratches, etc.), stress whitening tends to easily occur in the scratches themselves, and since the incident light from an oblique direction tends to be reflected as diffused light, the switching mechanism 34 is referred to as “dark field”. By switching to “illumination”, the brightness of the whitening flaw can be detected with high accuracy by the detection unit B.
[1] “Load addition condition”; tip moving distance X = 70 mm, load size: In proportion to the tip moving distance X, the load is increased from the initial load (0) to the maximum load (F = 180 N (Newton)). Form [2] “Lightness measurement condition”; scanning distance X = 70 mm, measurement pitch a = 0.1 mm

  FIGS. 5A to 5D show measurement results obtained by measuring the scratch lightness Ln and the surface lightness Sn for each of the evaluation objects P1 to P4 under the above-described conditions. The example of a display displayed on the display part 5 via is shown. As shown in these drawings, it can be seen that the measurement values of the lightness Ln of the evaluation objects P1 to P4 vary in various ways with respect to the scanning distance X, and similarly, the surface of the evaluation objects P1 to P4. It can be seen that the measured value of the brightness Sn also changes in various ways with respect to the scanning distance X. That is, it can be seen that the measurement values of the flaw lightness Ln and the surface lightness Sn change in various ways depending on the difference in the embossed shapes of the evaluation objects P1 to P4.

  6A to 6D show calculation results obtained by calculating the lightness change rate Mn for each of the evaluation objects P1 to P4 from the measurement values of the scratch lightness Ln and the surface lightness Sn shown in FIG. 3 shows a display example displayed on the display unit 5 from the control device 4 via the output unit 43. As shown in these figures, the calculated value of the lightness change rate Mn of the evaluation objects P1 to P4 reflects both the characteristics of the measurement value of the flaw lightness Ln and the characteristics of the measurement value of the surface lightness Sn. I understand that.

  "Table 1" shown below is a calculation result obtained by calculating the lightness evaluation value H for each evaluation object P1 to P4 from the lightness change rate Mn shown in FIG. 6, and the scratch creation start load of each evaluation object P1 to P4. The calculation result which computed Fa from the distance Xa which measured visually is shown. FIG. 7 is a graph of the calculation results shown in “Table 1” with the brightness evaluation value H as one parameter as the vertical axis and the flaw creation start load Fa as the other parameter as the horizontal axis. This shows a display example displayed on the display unit 5 from the control device 4 via the output unit 43.

  As shown in Table 1, it can be seen that the brightness evaluation value H and the scratch creation start load Fa tend to be different for each of the evaluation objects P1 to P4. Specifically, for example, the lightness evaluation value H is larger for the evaluation object P3 than the evaluation object P2, while the scratch creation start load Fa is larger for the evaluation object P2 than the evaluation object P3. It can be seen that the tendency of the brightness evaluation value H for each of the evaluation objects P1 to P4 is different from the tendency of the flaw creation start load Fa for each of the evaluation objects P1 to P4.

  These tendencies are also apparent from the graph shown in FIG. 7, and circles in which the calculation data of the brightness evaluation value H and the flaw creation start load Fa of each of the evaluation objects P1 to P4 are dispersed in the graph. I understand that. Note that the circles other than P1 to P4 in FIG. 7 plot the calculation data of the brightness evaluation value H and the flaw creation start load Fa when the other evaluation objects are evaluated under the same conditions.

  As shown in FIG. 7, the lightness evaluation value H is obtained by calculating the reciprocal of the value obtained by dividing the integrated value of the lightness change rate Mn by the scanning distance X. Therefore, the evaluation object becomes larger as the lightness evaluation value H is larger. It can be said that the entire scratch of P is inconspicuous. Further, since the scratch creation start load Fa is a load calculated from the distance Xa to the scratch creation start location, it can be said that the evaluation object P is less likely to be scratched as the scratch creation start load Fa is larger. Accordingly, as the brightness evaluation value H and the scratch creation start load Fa both increase to the upper right of the graph of FIG. 7, the evaluation object P is less likely to be damaged, and even if it is damaged, the balance of scratch resistance is excellent. On the contrary, the balance of the scratch resistance that the evaluation object P is likely to be damaged and conspicuous when it is damaged as it reaches the lower left of the graph of FIG. 7 where both the lightness evaluation value H and the scratch creation start load Fa are small. It can be evaluated as inferior. As a specific evaluation method for scratch resistance, for example, an evaluation reference line as indicated by Y in FIG. 7 is set on the graph, and the operation data of the evaluation object P to be evaluated is the evaluation reference line Y. However, although not shown, for example, the graph of FIG. 7 is divided into a plurality of regions, and in which region the evaluation is made. A specific evaluation of scratch resistance may be performed based on whether the calculation data of the evaluation object P is located. Further, the scratch resistance is not evaluated from the correlation between the lightness evaluation value H and the flaw creation start load Fa using the graph shown in FIG. 7 or the like, but the lightness evaluation value H and the flaw creation start load Fa are respectively determined. You may comprise separately, and you may comprise so that damage resistance may be evaluated comprehensively from those evaluation results. Specifically, for example, an evaluation threshold value for the lightness evaluation value H and a load threshold value for the flaw creation start load Fa are set, and whether or not the lightness evaluation value H of the evaluation object P exceeds the evaluation threshold value, It may be configured to evaluate whether the scratch creation start load Fa exceeds a load threshold and to comprehensively evaluate the scratch resistance from these evaluation results.

  In addition, although the present Example showed the evaluation example using what gave the surface of the black resin material which does not contain a talc as an evaluation object P1-P4 which gave different embossing, experiment of this inventor was shown. According to the results, it was confirmed that scratch resistance could be similarly evaluated for resin materials containing talc and red and blue resin materials other than black. Therefore, evaluation of scratch resistance between evaluation objects containing talc, evaluation of scratch resistance between evaluation objects containing talc and evaluation objects not containing, the same except for black The scratch resistance evaluation method of the present invention can be similarly applied to evaluation of scratch resistance between color evaluation objects and evaluation of scratch resistance between evaluation objects of different colors. Moreover, in the present Example, although the evaluation example using the thing made from a polypropylene was shown as evaluation object P1-P4, according to the experiment result of this inventor, it is similarly scratch-resistant also in resin materials other than a product made from a polypropylene. It was confirmed that the sex could be evaluated. Therefore, the scratch resistance evaluation method of the present invention can be similarly applied to the evaluation of scratch resistance between resin materials other than polypropylene and the evaluation of scratch resistance between evaluation objects of different materials. In short, any evaluation object can be evaluated by the scratch resistance evaluation method of the present invention as long as it is an evaluation object made of a resin having a textured surface.

  Further, in this embodiment, evaluation of scratch resistance is performed in a state in which “a chip for creating a whitening wound” is attached as the chip 22 of the scratch creating apparatus 2 and the switching mechanism 34 of the brightness measuring apparatus 3 is switched to “dark field illumination”. Although the example which performed this was shown, you may employ | adopt a different combination as a combination of the kind of the wound K created with the wound preparation apparatus 2, dark field illumination, and bright field illumination. Specifically, for example, the evaluation of scratch resistance may be performed in a state where a “chip for creating a glossy scratch” is attached as the chip 22 and the switching mechanism 34 is switched to “bright field illumination”. In the case of a glossy flaw, the unevenness on the surface of the evaluation object P tends to be flattened easily by the flaw, and the tendency to reflect incident light as it is is strong. Therefore, the glossy flaw is obtained by switching the switching mechanism 34 to “bright field illumination”. There is an advantage that the lightness of can be accurately detected by the detection unit B. Further, the size of the slit 38A shown in the present embodiment, the load addition condition and the lightness measurement condition of the above [1] and [2] are shown as an example, and the slit 38A having a different size or a different load is shown. Additional conditions and lightness measurement conditions may be employed.

[Another embodiment]
(1) In the above-described embodiment, an example in which the scratch resistance evaluation method according to the present invention is performed using the scratch resistance evaluation apparatus 1 has been described. You may comprise so that it may carry out by hand. Specifically, for example, it may be configured such that the operator scratches the surface of the evaluation object P manually by using a load applying device or the like without using the scratch creating device 2, for example, the brightness measuring device 3 Instead of using the movable table 31 or the control unit 44 of the control device 4, the operator may manually move the evaluation object P. Further, for example, the operator may perform various calculations manually without using the calculation unit 42 of the control device 4, for example, various calculation results on a predetermined recording sheet without using the display unit 5. Or the like may be described and evaluated.

(2) Contrary to said (1), you may comprise so that all or one part of what the operator performed manually by the said embodiment may be performed automatically. Specifically, for example, the scratch resistance evaluation apparatus 1 is integrated so that the scratch creating device 2, the lightness measuring device 3, the control device 4, the display unit 5, and the input unit 6 are attached to a device main body (not shown), A series of steps from the scratch creation step to the calculation result display is automatically performed by simply setting the evaluation object P that has not been created in the scratch resistance evaluation apparatus 1 and operating the input unit 6. May be.

(3) In the above embodiment, in the evaluation step, the lightness evaluation value H and the scratch creation start load Fa, which are parameters for evaluating scratch resistance, are displayed on the display unit 5 as a table, a graph, or the like. Although the example comprised so that the damage resistance of the evaluation target object P might be evaluated from the displayed table | surface, graph, etc. was shown, the control apparatus 4 automatically evaluated the damage resistance of the evaluation target object P, and the evaluation result May be displayed on the display unit 5. Specifically, for example, an evaluation threshold value for a single or a plurality of lightness evaluation values H and a load threshold value for a single or a plurality of scratch creation start loads Fa are set, and the control device is based on the evaluation threshold value and the load threshold value. The brightness evaluation value H and the scratch creation start load Fa are automatically evaluated in step 4, and the evaluation result is displayed on the display unit 5 in a stepwise manner (for example, excellent, good, normal, inferior, etc.). Good.

(4) In the above embodiment, an example in which the chip movement distance X is set as the scanning distance and the flaw lightness Ln and the surface lightness Sn are measured over the entire length of the scratch K has been shown. May be configured to measure a part of the lightness Ln and the surface lightness Sn of the scratch K, and set the scanning distance longer than the chip movement distance X so that the lightness Ln and the surface lightness are measured. You may comprise so that Sn may be measured continuously. Even in this case, it is possible to evaluate the scratch resistance of the evaluation object P from a part of the scratch K or a portion including the scratch K.

  The scratch resistance evaluation method and evaluation apparatus of the present invention is a resin material that has been subjected to embossing used for interior parts of vehicles such as automobiles and trucks, as well as OA equipment, home appliances, residential equipment, and household goods. It can be used for evaluation of scratch resistance.

1 Scratch resistance evaluation device 2 Scratch creation device (scratch creation means)
3 Lightness measuring device (lightness measuring means)
5 Display section (display means)
22 chip 38A slit 41 measuring part (lightness measuring means)
42 Calculation unit (calculation means)
A Irradiation part Fa Scratch creation start load H Lightness evaluation value K Scratch Ln Scratch lightness Mn Lightness change rate P Evaluation object Sn Surface lightness X Scanning distance (predetermined distance)
a Predetermined pitch

Claims (6)

It is a scratch resistance evaluation method for an evaluation object made of resin whose surface has been subjected to graining,
A scratch creating step for creating a linear scratch on the surface of the evaluation object by scanning the chip for a predetermined distance while increasing the pressing load;
A wound lightness measurement step for measuring the lightness of the light reflected by irradiating the wound with light at a predetermined measurement pitch along the longitudinal direction of the wound;
An evaluation value calculating step for calculating the lightness evaluation value of the scratch based on the lightness measured for each measurement pitch;
Scratch creation start load calculating step for calculating a scratch creation start load at which the scratch is actually created,
A scratch resistance evaluation method comprising: an evaluation step of evaluating scratch resistance of the evaluation object based on the lightness evaluation value and the scratch creation start load. Surface brightness for measuring the surface brightness of light received by irradiating light on the surface of the evaluation object before creating the scratch or the surface of the evaluation object on which the scratch has not been created, for each measurement pitch Measuring step,
The evaluation value calculating step calculates an average value of the surface brightness based on the surface brightness measured for each measurement pitch, and further, a difference between the brightness of the scratch measured for each measurement pitch and the average value. The integrated value of the brightness change rate obtained by dividing the integrated value by the average value is calculated, and the value obtained by dividing the integrated value by the predetermined distance or the inverse of the value obtained by dividing the integrated value by the predetermined distance is calculated as the lightness evaluation value. The scratch resistance evaluation method according to claim 1. The scratch creating step creates a straight whitening scar on the surface of the evaluation object,
3. The scratch resistance evaluation method according to claim 1, wherein the lightness measurement step measures the lightness of light received by irradiating light to the whitened scratch with a dark field for each measurement pitch. 4. The scratch creating step creates a linear gloss scratch on the surface of the evaluation object,
3. The scratch resistance evaluation method according to claim 1, wherein the lightness measurement step measures the lightness of light received by irradiating the glossy light with bright field at each measurement pitch. 4. A scratch resistance evaluation apparatus used in the scratch resistance evaluation method according to any one of claims 1 to 4,
A flaw creating means for creating a straight flaw on the surface of the evaluation object by scanning the chip for a predetermined distance while increasing the pressing load;
Lightness measurement means for measuring the lightness of light reflected by irradiating the wound from the irradiation unit for each measurement pitch along the longitudinal direction of the wound;
Calculation means for calculating the scratch creation start load and the brightness evaluation value;
A scratch resistance evaluation apparatus having display means for displaying the scratch creation start load and the brightness evaluation value.   The lightness measuring means receives light reflected by irradiating light from the irradiating unit through a slit elongated in a short direction of the scratch, and measures the lightness of the scratch for each measurement pitch. 5. The scratch resistance evaluation apparatus according to 5.

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