JP2006242719A - Solder material deterioration degree determining device, solder printer, solder material deterioration degree determination method, solder printing method, solder material deterioration degree determination program, solder printing program and computer-readable recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solder material deterioration degree determining device for determining the degree of deterioration of a solder material in a short time, in parallel with solder printing process. <P>SOLUTION: This device is equipped with an illumination part 20 for irradiating the surface of the solder material 1 with an inspection light, an imaging part 30 for imaging the surface of the solder material 1, and a deterioration degree determining part 42 for determining the degree of deterioration of the solder material 1, based on an imaged image imaged by the imaging part 30. In the constitution, the illumination part 20 irradiates the surface of the solder material 1 with the inspection light, and the imaging part 30 images the surface of the solder material 1. The degree of deterioration of the solder material 1 is determined by the deterioration degree determining part 42, based on the imaged image. Hereby, the degree of deterioration of the solder material can be determined simply, in a short time. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for determining the degree of deterioration of a solder material and a method for determining the degree of deterioration.

  When soldering an electronic component on a substrate such as a printed wiring board, first, a solder material is printed on the substrate, and the electronic component is mounted on the printed solder. Thereafter, by raising the temperature of the substrate, the solder on the substrate is melted and the electronic component is welded.

  In the solder material printing process described above, deterioration of the solder material can be cited as one of the causes of printing defects. One of the indexes indicating the deterioration of the solder material is an increase in the viscosity of the solder material. The viscosity of the solder material is low when the solder material is prepared, and increases with time. That is, the solder material becomes harder gradually. When the viscosity of the solder material increases, the solder material becomes difficult to be printed on the substrate, and printing blur occurs. Therefore, in order to prevent printing defects due to the deterioration of the solder material as described above, it is necessary to monitor the viscosity of the solder material.

  The solder material is prepared by mixing a solid metal ball and a flux (organic solvent component). Methods for measuring the degree of deterioration of the solder material and the solid solder material have been devised so far.

  For example, a viscometer that rotates a rotary wing in a solder material and measures the viscosity by a load applied to the wing has been put into practical use.

  In the invention disclosed in Patent Document 1, the flow rate of the solder material rotating on the substrate is measured by a laser sensor, and based on the correlation between the viscosity of the solder material and the flow rate obtained in advance. The viscosity of the solder material is calculated from the measured flow rate of the solder material.

  In the invention disclosed in Patent Document 2, the deterioration degree of the solder material is measured by chemically measuring the acid value of the flux. This method utilizes the property of oxidizing when solder deteriorates.

Further, in the invention disclosed in Patent Document 3, the atmospheric air ultraviolet photoelectron spectrum of a solid solder material is measured by atmospheric air ultraviolet photoelectron spectroscopy, and the obtained photoelectron spectrum is emitted from the surface oxide film of the solder material. The photoelectron emission intensity S is determined, and the obtained photoelectron emission intensity S is applied to the relationship between the previously obtained surface oxidation rate of the solder material and the photoelectron emission intensity S emitted from the surface oxide film. The surface oxidation rate is obtained.
JP 5-99831 A (published on April 23, 1993) Japanese Patent Publication No. 8-20434 (published March 4, 1996) Japanese Patent Laid-Open No. 10-082737 (published March 31, 1998)

  However, the conventional configuration has several problems. For example, in the viscometer having the rotary wing described above, since the viscometer is inserted into the solder material put in the pot, it is necessary to have enough solder material to fill the pot, which takes time and labor. There is. Furthermore, after the viscosity of the solder material is measured, the solder material must be returned to the solder printing process and the solder printing must be resumed. Therefore, it is necessary to stop the solder printing process and measure the viscosity.

  Further, in the invention described in Patent Document 1, the viscosity of the solder material can be measured only when the squeegee is driven, and there is a problem that the inspection object is limited to only the solder material being used in the printing process.

  In addition, in the invention described in Patent Document 2, since a special reagent is required, it takes time and measures the deterioration degree of the solder material in real time in parallel with the process of printing the solder material on the substrate. That is, there is a problem that it is difficult to measure the degree of deterioration of the solder material in-line.

  The invention described in Patent Document 3 can measure a solid solder material, but has a problem that it is difficult to measure a solder material whose surface is covered with a flux. Furthermore, there is a problem that ultraviolet rays harmful to the human body are required.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a solder material deterioration degree determination device that can determine the deterioration degree of a solder material in a short time without trouble. .

  In order to solve the above-described problem, the solder material deterioration degree determination device according to the present invention images the illumination unit that irradiates the surface of the solder material with the inspection light and the surface of the solder material that is irradiated by the illumination unit. It is characterized by comprising an image pickup unit and a deterioration degree judging means for judging the degree of deterioration of the solder material based on a picked-up image picked up by the image pickup unit.

In the above configuration, the illumination unit irradiates the surface of the solder material, which is an object to be inspected, with inspection light, and the imaging unit images the surface of the solder material. At this time, if irregularities are formed on the surface of the solder material, part of the regular reflection component of the inspection light emitted from the illumination unit is reflected in the direction of the imaging unit.
In other words, the captured image captured by the imaging unit changes depending on the unevenness on the surface of the solder material. Then, based on the correlation between the degree of deterioration of the solder material obtained in advance and the change in the captured image, the degree of deterioration determination means determines the degree of deterioration of the solder material. In addition, it is preferable to irradiate the said inspection light from the diagonal direction with respect to the said solder material.

  The unevenness on the surface of the solder material is formed as the solder material deteriorates. That is, when the solder material deteriorates, the viscosity of the solder material increases, and the unevenness of the surface of the solder material increases. Therefore, the deterioration degree of the solder material can be determined using this property. In other words, the degree of deterioration of the solder material can be determined by detecting the change in the captured image due to the increase in the unevenness on the surface of the solder material.

  Therefore, it is possible to easily determine the degree of deterioration of the solder material in a short time without contacting the solder material. Moreover, the degree of deterioration can be determined even with a small amount of solder material. Furthermore, when the solder material deterioration degree judging device of the present invention is used in combination with a solder printer, the degree of deterioration of the solder material used in the solder printer can be judged in real time in parallel with the solder printing process.

  Further, the deterioration degree determination means may determine the deterioration degree of the solder material based on luminance information acquired from the captured image.

  One of the changes in the captured image derived from the unevenness of the solder material surface is a change in luminance. That is, if the unevenness on the surface of the solder material increases, the luminance variation in the captured image obtained by imaging the surface of the solder material increases.

  Therefore, in the above configuration, the deterioration degree determination means extracts luminance information from the captured image, and determines the deterioration degree of the solder material based on the luminance information. Therefore, it is possible to easily calculate the degree of deterioration of the solder material without performing complicated processing.

  Further, the solder material deterioration degree judging device of the present invention further comprises parameter obtaining means for obtaining a parameter including at least one of information relating to the kind and composition of the solder material and information relating to the imaging condition, and the deterioration degree judging means includes Further, the degree of deterioration of the solder material may be determined based on the parameter.

  In the above configuration, the parameter acquisition unit acquires parameters relating to the type of the solder material and the imaging conditions, and the deterioration level determination unit determines the deterioration level of the solder material based on the parameters. Therefore, even when the type / composition of the solder material and the imaging conditions are different for each measurement, the deterioration degree judging means is obtained by acquiring information about the type / composition of the solder material and the imaging conditions via the parameter acquiring means. Therefore, it is possible to determine the degree of deterioration according to the type / composition of the solder material and the imaging conditions.

  In order to solve the above problems, a solder printing machine according to the present invention applies a solder material to a mask having an opening with an applicator, thereby printing the solder material on a substrate through the opening. A printer, a detection unit for detecting the operation of the applicator, an illumination unit for irradiating the surface of the solder material applied to the mask with inspection light, and a detection result of the detection unit, An imaging unit that images the surface of the solder material applied to the mask under the inspection light irradiated by the illumination unit, and a degree of deterioration of the solder material is determined based on the captured image captured by the imaging unit It is characterized by comprising a deterioration degree judging means.

  In the above configuration, when the detection unit detects that the solder material is applied to the mask by the applicator, the imaging unit images the surface of the solder material. With this configuration, imaging by the imaging unit is performed as soon as solder printing is completed. At this time, if irregularities are formed on the surface of the solder material, a part of the regular reflection component of the inspection light emitted from the illumination unit enters the imaging unit. Then, the deterioration degree determination means determines the deterioration degree of the solder material based on the captured image picked up by the image pickup unit.

  With the configuration described above, the degree of deterioration of the solder material can be easily determined in a short time, and the degree of deterioration can be determined even with a small amount of solder material. Therefore, the degree of deterioration of the solder material can be determined in parallel with the solder printing process, that is, in real time without stopping the solder printing process.

  Further, the deterioration degree determination means may determine the deterioration degree of the solder material based on luminance information acquired from the captured image.

  In the above configuration, the deterioration degree determination means extracts luminance information from the captured image, and determines the deterioration degree of the solder material based on the luminance information. Therefore, the degree of deterioration of the solder material can be easily determined in a short time without performing complicated processing, and the degree of deterioration of the solder material can be determined in real time without stopping the solder printing process.

  The solder printing machine of the present invention further includes parameter acquisition means for acquiring a parameter including at least one of information relating to the solder material and information relating to imaging conditions, and the deterioration degree determination means is further based on the parameter. The degree of deterioration of the solder material may be determined.

  In the above configuration, the parameter acquisition unit acquires parameters related to the type of solder material and the imaging conditions, and the deterioration level determination unit calculates the deterioration level of the solder material based on the parameters. Therefore, even if the type and composition of the solder material used in solder printing and the printing environment (imaging conditions) of the solder material are different, information necessary for determining the degree of deterioration is acquired via the parameter acquisition means. Thus, the deterioration degree determination means can determine the deterioration degree corresponding to the printing environment (imaging condition).

  Furthermore, the solder printer of the present invention may include a control unit that changes a printing condition based on a determination result of the deterioration degree determination unit.

  In the above configuration, the deterioration degree determination unit determines the deterioration degree of the solder material in real time, and the control unit optimizes the solder printing conditions based on the determination result of the deterioration degree determination unit. Therefore, as the degree of deterioration of the solder material increases, the printing speed and the printing pressure of the applicator can be adjusted. As a result, it is possible to perform solder printing while maintaining an optimal printing state according to the degree of deterioration of the solder material being used.

  In order to solve the above-described problems, the solder material deterioration degree determination method of the present invention is configured to illuminate the surface of the solder material with inspection light, and to capture an image of the surface of the solder material irradiated in the illumination step. And a deterioration degree determination step of determining the degree of deterioration of the solder material based on the captured image captured in the imaging step.

  With the above configuration, the degree of deterioration of the solder material can be easily determined in a short time without contacting the solder material, and the degree of deterioration can be determined even with a small amount of solder material.

  In order to solve the above-described problem, the solder material deterioration degree determination method of the present invention prints the solder material on the substrate through the opening by applying the soldering material to the mask having the opening with an applicator. A solder material deterioration degree determination method for determining a deterioration degree of a solder material applied to the mask in a solder printer, wherein a detection step of detecting an operation of the applicator and the solder applied to the mask An illumination process for irradiating the surface of the material with inspection light, and a surface of the solder material applied to the mask under the inspection light irradiated in the illumination process based on the detection result obtained in the detection process And a deterioration degree determining step of determining the deterioration degree of the solder material based on the captured image picked up in the imaging step.

  With the above configuration, it is possible to easily determine the degree of deterioration of the solder material in a short time without stopping the solder printing process.

  The solder material deterioration degree judging device and the solder printing machine may be realized by a computer. In this case, the solder material deterioration degree judging device and the solder printing machine are operated by operating the computer as the respective means. A solder material deterioration degree determination device, a solder printing machine deterioration degree determination program for a solder printer, a solder printing program, and a computer-readable recording medium recording the same are also included in the scope of the present invention.

  The solder material deterioration degree judging device according to the present invention, as described above, an illumination unit that irradiates the surface of the solder material with inspection light, an imaging unit that images the surface of the solder material irradiated by the illumination unit, Deterioration degree determination means for determining the deterioration degree of the solder material based on the captured image captured by the imaging unit.

  Therefore, it is possible to easily determine the degree of deterioration of the solder material in a short time without coming into contact with the solder material, and to determine the degree of deterioration even with a small amount of solder material.

  As described above, the solder printer according to the present invention is a solder printer that prints the solder material on the substrate through the opening by applying the solder material to the mask having the opening with the applicator. A detection unit that detects the operation of the applicator, an illumination unit that irradiates the surface of the solder material applied to the mask with inspection light, and an illumination unit that irradiates the detection unit based on the detection result of the detection unit. An imaging unit that images the surface of the solder material applied to the mask under the inspected light, and a deterioration degree determination that determines a deterioration level of the solder material based on a captured image captured by the imaging unit Means.

  Therefore, it is possible to easily determine the degree of deterioration of the solder material in a short time without stopping the solder printing process.

[Embodiment 1]
An embodiment of the present invention will be described below with reference to FIGS. The solder material deterioration degree determination apparatus of the present invention can be used both offline and inline. In this embodiment, an example of an offline form will be described. Here, the in-line means a form in which the degree of deterioration of the solder material used in the solder printing is determined in parallel with the above process without stopping the solder printing process. On the other hand, the off-line means a form in which the degree of deterioration of the solder material is determined independently of the solder printing process.

  First, a manufacturing method of the measurement sample 7 used in the present embodiment will be described with reference to FIG.

  FIG. 2 is a perspective view showing a method for producing a measurement sample for judging the degree of deterioration of the solder material using the solder material deterioration degree judging device of the present invention.

  The measurement sample 7 is an object to be inspected of the solder material deterioration determination device 10 according to the present embodiment, and is obtained by applying a solder material to the surface of a flat plate. In the present embodiment, as shown in FIG. 2, the measurement sample 7 is produced by applying the solder material 1 to the simple mask 6. The simple mask 6 is obtained by attaching an aluminum tape 3 (thickness 0.1 mm) from which a mold part 2 (10 × 15 mm) is removed to a copper plate 4. An appropriate amount of the solder material 1 is placed on the mold part 2 and slid while one side of the manual squeegee 5 as an applicator is in close contact with the surface to which the aluminum tape 3 is attached. Is applied. If a sufficient amount of solder material is not applied by one slide, the above operation is repeated a plurality of times.

  In addition, the structure of the simple mask 6 is not limited to said structure, It can change suitably. However, if the size of the mold part 2 becomes too small, it becomes difficult to image the surface of the solder material applied to the mold part 2, so that the mold part 2 has a size suitable for imaging. It is preferable to make it.

  Next, the configuration of the solder material deterioration degree determination apparatus 10 according to the present embodiment will be described with reference to FIG.

  FIG. 1 is a schematic block diagram showing a configuration of a solder material deterioration degree judging device 10 according to the present embodiment.

  As shown in FIG. 1, the solder material deterioration degree judging device 10 judges the degree of deterioration of the solder material 1 applied to the surface of the measurement sample 7, and irradiates the surface of the measurement sample 7 with light. Image processing as an illuminating unit 20, an imaging unit 30 that images the surface of the solder material 1 applied to the measurement sample 7, and a deterioration degree determination unit that performs predetermined processing to be described later on an image captured by the imaging unit 30 And an input / output unit 50 as input / output means for inputting information necessary for the determination to the image processing unit 40 and outputting the determination result of the image processing unit 40.

  The illumination unit 20 is positioned obliquely above the measurement sample 7 so that the surface of the measurement sample 7 can be irradiated with inspection light. The wavelength of the light emitted from the illuminating unit 20 is not particularly limited, and may be visible light or infrared light, as long as it is suitable for imaging the shape of the solder material surface. Also, the type of light emitted from the illumination unit 20 is not particularly limited, and it may be a normal light beam or a laser beam, which is suitable for imaging the shape of the solder material surface. That's fine.

  The imaging unit 30 receives light reflected on the surface of the solder material 1 applied to the measurement sample 7 and forms a captured image indicating the surface shape of the solder material 1, and is positioned above the solder material 1. Yes. As this imaging unit 30, for example, a CCD camera or a CCD line sensor can be used. The type of light that can be detected by the imaging unit 30 only needs to match the type of inspection light emitted by the illumination unit 20. In addition, the range captured by the imaging unit 30 may be the entire region of the solder material 1 applied to the measurement sample 7 or a part thereof, and measurement with high reproducibility (less variation). It may be in a range where results can be obtained.

  The image processing unit 40 determines whether or not the solder material 1 is deteriorated based on a captured image obtained by imaging the surface of the solder material 1, and calculates the degree of unevenness of the surface of the solder material 1. 41 and a deterioration degree determination unit 42 that determines the deterioration degree of the solder material 1 based on the calculated degree of unevenness.

  The unevenness degree calculation unit 41 extracts surface shape information indicating the surface shape of the solder material 1 from the captured image, and calculates the unevenness degree of the surface of the solder material 1 based on the surface shape information. A method for calculating the degree of unevenness will be described later.

  The deterioration degree determination unit 42 determines the deterioration degree based on the unevenness degree of the surface of the solder material 1 calculated by the unevenness degree calculation unit 41 and the parameters described later input via the input unit 51. To do. A method for determining the degree of deterioration will be described later.

  The input / output unit 50 includes an input unit 51 that inputs information related to the deterioration degree determination, and an output unit 52 that outputs a determination result obtained by the deterioration degree determination unit.

  The input unit 51 is used by the user of the solder material deterioration degree determination apparatus 10 to input parameters necessary for determining the deterioration degree of the solder material, and functions as a parameter acquisition unit. The parameters include information on the type and composition of the solder material that is the object to be inspected, and information on the imaging conditions, for example, the type and amount of the inspection light emitted from the illumination unit 20. The input unit 51 may be anything as long as the user can input the parameters, may have a plurality of buttons (keys), or may be a display device having a touch panel type setting operation unit. Good.

  The input format of the parameters is not particularly limited, and may be a format selected from a predetermined table displayed on the display device, or the user inputs numerical values related to the name of the solder material and the imaging conditions. It may be formatted.

  The output unit 52 notifies the determination result of the deterioration level determination unit 42 to the user. The output unit 52 may include a display device (not shown) having a liquid crystal screen or the like, or may include a printer (not shown) that performs the above notification using a paper medium. May have a speaker (not shown) for performing the above notification. The output unit 52 may be independent from the input unit 51 or may be integrated.

  Next, a general flow of processing in the solder material deterioration degree determination apparatus 10 will be described with reference to FIGS. 1 and 3.

  FIG. 3 is a schematic diagram showing an example of an embodiment when the solder material deterioration degree judging device of the present invention is used offline.

  The measurement sample 7 to which the solder material 1 is applied is disposed immediately below the imaging unit 30 and irradiated with inspection light emitted from the illumination unit 20. A part of the regular reflection component of the inspection light irradiated on the measurement sample 7 is reflected in the direction of the imaging unit 30. The imaging unit 30 captures a part of the regular reflection component reflected on the surface of the measurement sample 7 and images the surface of the measurement sample 7.

  The captured image captured by the imaging unit 30 is sent to the unevenness calculation unit 41. The unevenness degree calculation unit 41 extracts luminance information from the captured image, and calculates the surface unevenness degree from the luminance information. The surface unevenness is a value representing how uneven the surface of the solder material 1 is. The surface unevenness increases as the surface of the solder material 1 becomes rough. A method for calculating the degree of surface irregularity will be described later.

  Information about the surface unevenness calculated by the unevenness calculating unit 41 is sent to the deterioration determining unit 42. The deterioration degree determination unit 42 calculates a relative value between the calculated unevenness degree of the solder material 1 and a predetermined value (reference value), and calculates the deterioration degree of the solder material 1 from the magnitude of the relative value. That is, a reference value (threshold value) is set in advance as to how much the surface unevenness of the solder material is deteriorated, and the deterioration degree of the solder material is determined based on the reference.

  Then, the determination result derived by the deterioration degree determination unit 42 is output by the output unit 52. The output by the output unit 52 may be performed via a display device (not shown) having a liquid crystal screen or the like to the operator of the solder material deterioration degree judging device, or a printer or the like (not shown). May be output to a paper medium or may be accompanied by sound.

  Next, the principle of the solder material deterioration degree determination method of the present invention will be described with reference to FIGS.

  FIG. 4 is a diagram illustrating an image obtained by imaging the surface of a new and deteriorated solder material.

  FIG. 5 is a graph showing the correlation between the surface roughness of the solder material and the viscosity.

  FIG. 6 is a schematic diagram showing the principle of detection of the solder material surface state in the present embodiment.

  As shown in FIG. 4, the unevenness of the surface increases as the solder material deteriorates. This phenomenon is caused by an increase in the viscosity of the solder material as it deteriorates (see FIG. 5). That is, the degree of deterioration of the solder material, the degree of surface unevenness, and the viscosity are correlated, and as the deterioration of the solder material proceeds, the viscosity is improved and as a result, the degree of surface unevenness of the solder material increases. Therefore, the degree of deterioration of the solder material can be calculated by measuring the degree of surface irregularity of the solder material.

  The surface unevenness degree of the solder material is detected based on the principle shown in FIG. The inspection light irradiated from the illumination unit 20 located obliquely with respect to the measurement sample 7 is reflected on the surface of the solder material 1. At this time, when the surface of the solder material 1 is not uneven, that is, in the case of a new solder material, the inspection light is regularly regularly reflected in the direction opposite to the illumination unit 20. For this reason, the imaging unit 30 captures an image with little luminance variation.

  On the other hand, when the surface of the solder material 1 is uneven, that is, in the case of a deteriorated solder material, a part of the regular reflection component of the inspection light enters the imaging unit 30. Therefore, the luminance of a part of the captured image obtained by imaging the surface of the solder material 1 is increased. As a result, in the captured image obtained by imaging the surface of the deteriorated solder material, the luminance variation becomes large.

  Here, the calculation method of the surface unevenness will be specifically described.

  The degree of unevenness of the surface of the solder material is calculated based on a captured image obtained by imaging the surface of the solder material. Any calculation method may be used, but in the present embodiment, a method of calculating the degree of surface unevenness based on luminance information (luminance value) extracted from the captured image is used.

  There are a plurality of methods for calculating the degree of surface irregularity based on the luminance value, but in this embodiment, a method for calculating the degree of surface irregularity from the standard deviation of the luminance value is used.

  The method of calculating the surface unevenness from the standard deviation of the brightness value is to calculate the surface unevenness from the variation (standard deviation) of the brightness value in the captured image. In this method, first, a region having a specific area is set in the captured image. Then, an average luminance value in the area is calculated. The average value calculated as described above, the luminance value (measured value) for each pixel in the region, and the number of pixels in the region (number of data) are applied to the following formula (Equation 1), and the standard The deviation is obtained, and this standard deviation is used as the degree of surface irregularity.

  Based on the surface unevenness degree of the solder material 1 calculated as described above, the deterioration degree determination unit 42 determines the deterioration degree of the solder material 1. The standard of how much the surface roughness is judged to be that the solder material has deteriorated depends on the type of solder material and the composition of the solder material, that is, the mixing ratio of solid metal balls and flux. Different. Moreover, the said reference | standard may change with imaging conditions, for example, the light quantity and kind of the test | inspection light of the illumination part 20. When using the same composition of solder material and determining the above-mentioned deterioration level under the same imaging conditions, a predetermined reference value (threshold value) stored in an auxiliary storage unit (not shown) included in the deterioration level determination unit 42 is used. ) To determine the degree of deterioration. That is, the calculated surface irregularity is compared with the reference value, and when the surface irregularity exceeds the reference value, it is determined that the solder material of the object to be inspected is deteriorated.

  On the other hand, when the composition of the solder material and the imaging conditions change, information (parameters) necessary for determining the degree of deterioration is input via the input unit 51 (parameter acquisition means) for each measurement or each time the imaging conditions change. Then, it may be supplied to the deterioration degree determination unit 42. Then, the deterioration degree determination unit 42 determines the deterioration degree of the solder material 1 based on the input parameters and the surface unevenness degree of the solder material 1.

  For example, when the amount of inspection light emitted from the illumination unit is small, the reference value (threshold value) needs to be lowered.

  The parameter input format may be a format in which the user directly inputs the reference value, or a format in which the user inputs the type, composition, and imaging conditions of the solder material. The deterioration level determination unit 42 may calculate the reference value corresponding to the above.

  The determination result by the deterioration degree determination unit 42 may be one of “degraded” or “not deteriorated”, or the deterioration degree is divided into several levels. Also good. Further, in addition to the determination result, the surface unevenness degree may be displayed as a numerical value.

  In the above description, the method for calculating the surface unevenness from the standard deviation of the luminance values is described as the method for calculating the surface unevenness, but the surface unevenness is calculated from the average value of the luminance values between the adjacent pixels. You may use the method of calculating.

  FIG. 7 is a diagram for explaining a method of calculating the surface irregularity degree of the solder material.

In this method, first, as shown in FIG. 7, the luminance value in a certain pixel (referred to herein as a22) of the captured image and eight pixels (a11-13, a21, a23, a31) around the pixel a22. The difference from the luminance value in (33) is calculated and added. Then, the above calculation is performed for all the pixels in the set area, and the calculated values are summed. By dividing the total value by the number of pixels in the region, an average value of luminance differences between adjacent pixels is calculated.
The above calculation is performed by the calculation represented by the following mathematical formula (Equation 2).

And the average value of the brightness | luminance difference between the adjacent pixels calculated is used as a surface unevenness degree.

  The difference between the surface unevenness calculated as described above and the above-described reference value (threshold value) is obtained, and when the surface unevenness exceeds the reference value, the solder material of the object to be inspected deteriorates. Judge that Further, the degree of deterioration may be classified in stages based on the difference (relative value) between the surface roughness and the reference value.

  In the above configuration, the deterioration degree determination unit 42 determines the deterioration degree of the solder material 1 based on the unevenness degree calculated by the unevenness degree calculation unit 41. However, the unevenness degree may not be calculated. In that case, the captured image of the surface of the solder material 1 acquired by the imaging unit 30 is sent to the degradation level determination unit 42, and the degradation level determination unit 42 determines the degradation level of the solder material 1 based on the captured image. to decide. In this case, the deterioration level determination method by the deterioration level determination unit 42 includes, for example, a method of determining the deterioration level of the solder material based on the correlation between the luminance variation of the captured image and the deterioration level of the solder material. It is done. That is, the degree of deterioration may be determined based on a criterion for determining how much the luminance variation of the captured image is increased and determining that the solder material is deteriorated.

  In the above-described configuration, the unevenness degree calculation unit 41 calculates the unevenness degree based on the captured image. However, the viscosity of the solder material 1 that is an object to be inspected may be calculated based on the captured image. . In that case, a viscosity calculation unit (not shown) is provided, and the captured image of the surface of the solder material 1 acquired by the imaging unit 30 is sent to the viscosity calculation unit. The viscosity of the solder material 1 may be determined based on the correlation between the luminance variation and the viscosity of the solder material. Then, the degradation level determination unit 42 may determine the degradation level of the solder material 1 based on the viscosity calculated by the viscosity calculation unit.

  As described above, the solder material deterioration degree determination apparatus 10 according to the present embodiment images the illumination unit 20 that irradiates the surface of the solder material 1 with the inspection light and the surface of the solder material 1 that is irradiated by the illumination unit 20. The image pickup unit 30 and the deterioration degree determination unit 42 that determines the deterioration degree of the solder material 1 based on the picked-up image picked up by the image pickup unit 30.

  According to said structure, the illumination part 20 irradiates the test | inspection light to the surface of the solder material 1 which is a to-be-inspected object, the imaging part 30 images the surface of the solder material 1, and includes the surface shape information of the solder material 1 A captured image is formed. Then, based on the captured image, the deterioration degree determination means determines the deterioration degree of the solder material 1. Therefore, it is possible to easily determine the degree of deterioration of the solder material in a short time without contacting the solder material. Moreover, the degree of deterioration can be determined even with a small amount of solder material.

  Moreover, the solder material deterioration degree determination apparatus 10 according to the present embodiment may be configured such that the deterioration degree determination unit 42 determines the deterioration degree of the solder material 1 based on the luminance information acquired from the captured image. .

  According to the above configuration, the degradation level determination unit 42 extracts luminance information from the captured image, and based on the correlation between the luminance variation of the captured image and the degradation level of the solder material, the degradation of the solder material 1 Judge the degree. Therefore, the deterioration degree of the solder material can be calculated in a short time without performing complicated processing.

  In addition, the solder material deterioration degree determination apparatus 10 according to the present embodiment includes an input unit 51 as a parameter acquisition unit that acquires parameters including at least one of information on the type and composition of the solder material 1 and information on imaging conditions. Further, the deterioration degree determination unit 42 may further be configured to determine the deterioration degree based on the parameters.

  In the above configuration, the input unit 51 acquires parameters relating to the type / composition of the solder material 1 and the imaging conditions, and outputs the parameters to the deterioration level determination unit 42, and the deterioration level determination unit 42 performs soldering based on the parameters. The degree of deterioration of the material 1 is determined. Therefore, even if the type / composition of the solder material 1 and the imaging conditions are different for each measurement, it is possible to determine the degree of deterioration by acquiring information about the type / composition of the solder material 1 and the imaging conditions via the input unit 51. The unit 42 can determine the degree of deterioration according to the type and composition of the solder material 1 and the imaging conditions.

  In addition, the solder material deterioration degree determination device 10 according to the present embodiment includes an unevenness degree calculation unit 41 that calculates the unevenness degree of the surface of the solder material 1 based on a captured image indicating the surface shape of the solder material 1, and the unevenness degree. It may be configured to include a deterioration degree determination unit 42 that determines the deterioration degree of the solder material 1 based on the degree of unevenness calculated by the calculation unit 41.

  According to said structure, the unevenness | corrugation degree calculation part 41 calculates the unevenness | corrugation degree of the surface of the solder material 1 based on the said captured image, and a deterioration degree judgment is based on the correlation with the said unevenness | corrugation degree and the deterioration degree of a solder material. The part 42 determines the degree of deterioration of the solder material 1. Therefore, the degree of deterioration of the solder material can be easily determined in a short time based on the degree of unevenness on the surface of the solder material.

  Further, the solder material deterioration degree determination device 10 according to the present embodiment includes an illumination unit that irradiates the surface of the solder material with inspection light, an imaging unit that images the surface of the solder material irradiated by the illumination unit, A surface shape information acquisition unit that acquires surface shape information of the solder material from a captured image captured by the imaging unit, and a deterioration degree determination unit that determines a deterioration degree of the solder material based on the surface shape information. It may be a configuration.

  Further, in the solder material deterioration degree determination device 10 according to the present embodiment, the surface shape information may be luminance information.

  Further, the solder material deterioration degree determination device 10 according to the present embodiment includes an illumination unit that irradiates light to the solder material, an imaging unit that images the surface of the solder material irradiated by the illumination unit, and the imaging unit. A configuration may be provided that includes a processing unit that measures the degree of deterioration of the solder material from a captured image and an output unit that displays and outputs the measurement result obtained by the processing unit.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. In the present embodiment, an example of a mode in which the solder material deterioration degree measurement of the present invention is used in-line will be described. In addition, about the member similar to Embodiment 1, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  First, the configuration of the solder printer 100 according to the present embodiment will be described with reference to FIGS. 8 and 9.

  FIG. 8 is a schematic diagram showing the configuration of the solder printer 100 according to the present embodiment.

  FIG. 9 is a plan view showing the configuration of the solder printer 100 according to the present embodiment. FIG. 9 is a top view of the solder printer 100, and the image processing unit 40 and the input / output unit 50 are not shown in this figure.

  As shown in FIGS. 8 and 9, the solder printer 100 detects the movement of the squeegee 103 and the squeegee 103 that applies the solder material 101 to the metal mask 102 in addition to the configuration of the solder material deterioration degree determination device 10. And a detection unit 110.

  The solder printing machine 100 prints the solder material 101 on a substrate such as a wiring board through the opening by applying the solder material 101 to the metal mask 102 having the opening with the squeegee 103. Unlike the solder material deterioration degree determination device 10, in the solder printer 100, the object to be inspected is the solder material 101 applied on the metal mask, and the solder material 101 deteriorates in parallel with the printing process by the squeegee 103. Degree is judged.

  The metal mask 102 is a metal plate placed on a substrate (not shown) that is a substrate to be printed, and has an opening (not shown) with a specific pattern. When the solder material 101 is applied to the metal mask 102 by the squeegee 103, the solder material 101 filled in the opening is printed on the substrate.

  The squeegee 103 is a plate-shaped applicator arranged so that one side thereof is in pressure contact with the upper surface of the metal mask 102. The material of the squeegee 103 is not particularly limited, and may be urethane rubber or metal. The squeegee 103 applies the solder material 101 to the surface of the metal mask 102 by sliding on the upper surface of the metal mask 102. Although only one squeegee 103 is shown in FIG. 8, a configuration including a plurality of squeegees may be used.

  The detection unit 110 detects the movement of the squeegee 103, and may be anything that can detect the movement of an object, such as a photoelectric sensor. The detection unit 110 detects that the squeegee 103 has moved to a specific position, and outputs the position detection information to the imaging unit 30. With the configuration described above, the surface of the solder material 101 can be imaged by the imaging unit 30 when the solder printing process by the squeegee 103 is completed. That is, the specific position means the position of the squeegee 103 at the end of the solder printing process, and the position detection information can be understood as the end information of the solder printing process.

  In addition, the position at which the squeegee 103 is moved is regarded as the end of one printing process, in other words, the position at which the squeegee 103 is moved to be imaged by the imaging unit 30 is appropriately set. The squeegee 103 may be moved to one end of the metal mask 102, or may be separated from the metal mask 102 as the squeegee 103 is lifted. It may be a point in time.

  The illumination unit 20 is located obliquely above the solder material 101 so that the surface of the solder material 101 can be irradiated with inspection light. The illumination unit 20 may always irradiate the inspection light, or may irradiate the inspection light only at the time of imaging by the imaging unit 30 in conjunction with the imaging operation of the imaging unit 30.

  The imaging unit 30 receives light reflected on the surface of the solder material 101 and forms a captured image indicating the surface shape of the solder material 101, and is positioned above the solder material 101. The imaging unit 30 forms the captured image based on the position detection information output from the detection unit 110, that is, images the surface of the solder material 101.

  It is preferable that the imaging region 30 capture an image is a non-contact region that is not in contact with the substrate in the region of the metal mask 102 to which the solder material 101 is applied. As described above, the metal mask 102 is placed on the substrate. In the contact region of the metal mask 102 that is in contact with the substrate (underlying the substrate), the amount of solder material 101 applied is extremely small. This is because the printing pressure of the squeegee 103 becomes high because the substrate is laid down, and the solder material 101 on the surface of the contact area is easily peeled off by the squeegee 103. Therefore, in order to perform highly reliable measurement, it is preferable to image the surface irregularities of the solder material 101 applied to the non-contact region.

  Moreover, it is preferable that the range imaged by the imaging unit 30 is a region excluding the opening of the metal mask 102. This is because the area of the opening is generally small and it is difficult to image only the opening.

  Next, a general flow of processing in the solder printer 100 will be described with reference to FIG.

  FIG. 10 is a flowchart showing the flow of processing in the solder printer 100. FIG. 10 shows the flow of processing when imaging by the imaging unit 30 is performed when the squeegee 103 is lifted.

  When one step of the solder printing is completed and the squeegee 103 moves above the metal mask 102, the detection unit 110 detects this movement (step 1).

  The detection result (position detection information) of the detection unit 110 is sent to the imaging unit 30. When receiving the position detection information, the imaging unit 30 images the surface of the solder material 101 (step 2).

  The captured image captured by the imaging unit 30 is sent to the degradation degree determination unit 42. The deterioration degree determination unit 42 determines whether or not the solder material 101 has deteriorated based on the captured image (step 3).

  The determination result of the deterioration degree determination unit 42 is sent to the output unit 52, and the output unit 52 outputs the determination result (step 4).

  In the processing described above, the captured image captured by the imaging unit 30 is sent to the degradation level determination unit 42, and the degradation level determination unit 42 determines the degradation level of the solder material 101 based on the captured image. However, as described in the first embodiment, the surface unevenness degree of the solder material 101 may be calculated based on the captured image, or the viscosity of the solder material 101 may be calculated based on the captured image. The deterioration degree determination unit 42 may determine the deterioration degree of the solder material 101 based on the calculated surface unevenness degree or the viscosity.

  Further, when the deterioration degree determination unit 42 determines that the deterioration degree of the solder material 101 has exceeded a predetermined value, the output unit 52 notifies that the deterioration degree of the solder material 101 has exceeded a predetermined value. May be. As a notification method in this case, a character “Solder material has deteriorated” may be displayed on a display unit (not shown), or an alarm sound may be emitted from a speaker (not shown).

  As shown in FIG. 11, the solder printer 100 according to the present embodiment may further include a control unit 120 as a control unit that controls the printing speed and / or the printing pressure.

  FIG. 11 is a schematic diagram showing a configuration of the solder printer 100 according to the present embodiment including the control unit 120.

  The control unit 120 receives the determination result of the deterioration level of the solder material 101 from the deterioration level determination unit 42, and controls the printing speed and / or printing pressure of the own apparatus, that is, the solder printer 100, based on the determination result. In other words, the solder printing machine 100 controls the printing speed and / or printing pressure of its own device by feeding back the determination result of the degree of deterioration of the solder material 101 via the control unit 120.

  Controlling the operation of the squeegee 103 is a method for controlling the printing speed. Specifically, it is preferable to reduce the operating speed of the squeegee 103 as the solder material 101 deteriorates, that is, to reduce the printing speed. This is because when the solder material 101 is deteriorated, the viscosity of the solder material 101 is increased and printing fading is likely to occur, and it is easy to prevent printing fading by reducing the printing speed.

  One method for controlling the printing pressure is to control the operation of the squeegee 103. Specifically, it is preferable to increase the operating pressure of the squeegee 103, that is, increase the printing pressure as the solder material 101 deteriorates. This is because when the solder material 101 is deteriorated, the viscosity of the solder material 101 is increased, and printing fading is likely to occur, and by increasing the printing pressure, it is easy to prevent printing fading.

  Further, when the deterioration degree determination unit 42 determines that the deterioration degree of the solder material 101 exceeds a predetermined value, the control unit 120 may temporarily stop the operation of the squeegee 103. Then, as described above, the fact that the degree of deterioration of the solder material 101 has exceeded a predetermined value may be notified, and the user of the solder printer 100 may be prompted to replace the solder material.

  As described above, the solder printing machine 100 according to the present embodiment applies the solder material 101 to the substrate by applying the solder material 101 to the metal mask 102 having the opening by the squeegee 103. Irradiation by the illumination unit 20 based on the detection unit 110 that detects the operation of the squeegee 103, the illumination unit 20 that irradiates the surface of the solder material 101 applied to the metal mask 102 with inspection light, and the detection result of the detection unit 110 The imaging unit 30 that images the surface of the solder material 101 applied to the metal mask 102 under the inspection light, and the deterioration that determines the degree of degradation of the solder material based on the captured image captured by the imaging unit 30 The degree determination unit 42 is provided.

  With the configuration described above, the degree of deterioration of the solder material can be easily determined in a short time, and the degree of deterioration can be determined even with a small amount of solder material. Therefore, the degree of deterioration of the solder material can be determined in parallel with the solder printing process, that is, in real time without stopping the solder printing process. As a result, the progress of deterioration of the solder material can be predicted, and the solder material can be exchanged at an appropriate timing, so that it is possible to prevent solder printing defects due to the deterioration of the solder material. Therefore, it is possible to maintain the quality of the solder-printed board without reducing the operating rate of the solder printing line.

  In the solder printer 100 according to the present embodiment, the deterioration degree determination unit 42 may be configured to determine the deterioration degree of the solder material 101 based on the luminance information acquired from the captured image.

  According to the above configuration, the deterioration degree determination unit 42 extracts luminance information from the captured image, and determines the deterioration degree of the solder material 101 based on the luminance information. Therefore, it is possible to easily determine the degree of deterioration of the solder material 101 in a short time simply by performing image processing on the captured image. As a result, the deterioration degree of the solder material can be determined in real time without stopping the solder printing process.

  The solder printer 100 according to the present embodiment further includes an input unit 51 that acquires a parameter including at least one of information related to the type and composition of the solder material 101 and information related to the imaging conditions, and a deterioration degree determination unit. Further, 42 may be configured to determine the degree of deterioration of the solder material 101 based on the above parameters.

  According to the above configuration, the input unit 51 acquires parameters regarding the imaging conditions such as the parameters regarding the type and composition of the solder material 101 and the amount of the inspection light emitted from the illumination unit 20, and the deterioration degree is determined based on the parameters. The unit 42 calculates the degree of deterioration of the solder material 101. Therefore, even when the type and composition of the solder material used in the solder printing machine 100 and the judgment condition (printing environment) of the solder material are different, information necessary for judging the degree of deterioration is appropriately input via the input unit 51. By providing it to the deterioration degree determination unit 42, it is possible to determine the optimum deterioration degree corresponding to the printing condition (determination condition).

  Furthermore, the solder printer 100 according to the present embodiment may be configured to include a control unit 120 that changes the printing conditions of the own machine based on the determination result of the deterioration degree determination unit 42.

  According to the above configuration, the deterioration degree determination unit 42 determines the deterioration degree of the solder material 101 in real time, and the control unit 120 optimizes the solder printing conditions of the own machine based on the determination result of the deterioration degree determination unit 42. To do. Therefore, it is possible to perform solder printing while maintaining an optimal printing state according to the degree of deterioration of the solder material being used. Further, when the deterioration degree determination unit 42 determines that the deterioration degree of the solder material 101 exceeds a predetermined value, the control unit 120 can also temporarily stop the operation of the squeegee 103. As a result, it is possible to prevent the solder printer 100 from continuing to operate while in a defective printing state.

  The solder printing machine 100 according to the present embodiment applies the solder material 101 to the metal mask 102 having an opening by the squeegee 103, thereby applying the solder material 101 to the substrate. The detection unit 110 to detect, the illumination unit 20 that irradiates the surface of the solder material 101 applied to the metal mask 102 with the inspection light, and the inspection light irradiated by the illumination unit 20 based on the detection result of the detection unit 110 Below, the imaging part 30 which images the surface of the solder material 101 apply | coated to the metal mask 102, and the unevenness | corrugation degree calculation part which calculates the unevenness | corrugation degree of the surface of the solder material 101 based on the captured image imaged by the imaging part 30 41 and a deterioration degree determination unit 42 that determines the deterioration degree of the solder material 101 based on the unevenness degree calculated by the unevenness degree calculation part 41. .

  The solder printer 100 according to the present embodiment is a solder printer having a squeegee structure, and includes a detection unit that detects completion of the squeegee lift, an illumination unit that irradiates light to the solder material, and solder that is irradiated by the illumination unit. A configuration may be provided that includes an imaging unit that images the surface of the material, a processing unit that measures the degree of deterioration of the solder material from an image captured by the imaging unit, and an output unit that displays and outputs the measurement result to the outside.

  Finally, each block of the solder material deterioration degree determination device 10 and the solder printer 100 may be configured by hardware logic, or may be realized by software using a CPU as follows.

  That is, the solder material deterioration degree judging device 10 and the solder printer 100, a CPU (central processing unit) for executing a control program instruction for realizing each function, a ROM (read only memory) storing the program, and the program A RAM (random access memory) to be developed, a storage device (recording medium) such as a memory for storing the program and various data, and the like are provided. An object of the present invention is to provide a computer program code (execution format program, intermediate code program, source program) of a control program for the solder material degradation degree determination device 10 and the solder printer 100 that is software for realizing the above-described functions. Is supplied to the solder material deterioration degree determination device 10 and the solder printer 100, and the computer (or CPU 52 or MPU) reads out and executes the program code recorded on the recording medium. Can also be achieved.

  Examples of the recording medium include tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and disks including optical disks such as CD-ROM / MO / MD / DVD / CD-R. Card system such as IC card, IC card (including memory card) / optical card, or semiconductor memory system such as mask ROM / EPROM / EEPROM / flash ROM.

  Further, the solder material deterioration degree determination device 10 and the solder printer 100 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Further, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth ( (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  Thus, in this specification, the means does not necessarily mean physical means, but includes cases where the functions of the means are realized by software. Further, the function of one means may be realized by two or more physical means, or the functions of two or more means may be realized by one physical means.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  Since the deterioration degree of the solder material can be easily determined in a short time, the present invention can be applied to solder printing that needs to determine the deterioration degree of the solder material in real time.

It is a schematic block diagram showing the structure of the solder material deterioration degree judgment apparatus 10 concerning this Embodiment. It is a perspective view which shows the method of producing the measurement sample for judging the deterioration degree of a solder material using the solder material deterioration degree judgment apparatus of this invention. It is a schematic diagram which shows an example of embodiment at the time of using the solder material degradation degree judgment apparatus of this invention offline. It is a figure which shows the image which imaged the surface of the solder material of a new article and deteriorated goods. It is a graph which shows the correlation with the surface unevenness degree of a solder material, and a viscosity. It is a schematic diagram which shows the detection principle of the solder material surface state in this Embodiment. It is a figure for demonstrating the calculation method of the surface unevenness degree of a solder material. It is a schematic diagram showing the structure of the solder printer 100 concerning this Embodiment. It is a top view showing the structure of the solder printer 100 concerning this Embodiment. 3 is a flowchart showing a flow of processing in the solder printer 100. It is a schematic diagram which shows the structure of the solder printing machine 100 provided with the control part 120 concerning this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solder material 10 Solder material degradation degree judgment apparatus 20 Illumination part 30 Imaging part 42 Degradation degree judgment part (degradation degree judgment means)
51 Input unit (parameter acquisition means)
100 Solder Printer 110 Detection Unit 120 Control Unit (Control Unit)

Claims (12)

An illumination unit that irradiates the surface of the solder material with inspection light;
An imaging unit for imaging the surface of the solder material irradiated by the illumination unit;
A solder material deterioration degree judging device comprising: a deterioration degree judging means for judging the degree of deterioration of the solder material based on a picked up image picked up by the image pickup section.   The solder material deterioration degree determination apparatus according to claim 1, wherein the deterioration degree determination means determines the deterioration degree of the solder material based on luminance information acquired from the captured image. A parameter acquisition means for acquiring a parameter including at least one of the information on the type and composition of the solder material and the information on the imaging condition;
The solder material deterioration degree judging device according to claim 1, wherein the deterioration degree judging means further judges the degree of deterioration of the solder material based on the parameter. A solder printing machine that prints the solder material on a substrate through the opening by applying a solder material to a mask having an opening with an applicator,
A detection unit for detecting the operation of the applicator;
An illumination unit for irradiating the surface of the solder material applied to the mask with inspection light;
Based on the detection result of the detection unit, under the inspection light irradiated by the illumination unit, an imaging unit that images the surface of the solder material applied to the mask;
A solder printing machine, comprising: a deterioration degree determination unit that determines a deterioration degree of the solder material based on a captured image picked up by the image pickup unit.   5. The solder printing machine according to claim 4, wherein the deterioration degree determination means determines the deterioration degree of the solder material based on luminance information acquired from the captured image. A parameter acquisition means for acquiring a parameter including at least one of the information on the type and composition of the solder material and the information on the imaging condition;
6. The solder printing machine according to claim 4, wherein the deterioration degree determining means further determines the deterioration degree of the solder material based on the parameter.   The solder printer according to claim 4, further comprising a control unit that changes a printing condition based on a determination result of the deterioration degree determination unit. An illumination process for irradiating the surface of the solder material with inspection light;
An imaging step of imaging the surface of the solder material irradiated in the illumination step;
A deterioration degree determination step of determining a deterioration degree of the solder material based on a captured image picked up in the imaging step. By applying a solder material to a mask having an opening with an applicator, in a solder printer that prints the solder material on a substrate through the opening, the degree of deterioration of the solder material applied to the mask is determined. A method for judging the degree of deterioration of solder material,
A detection step of detecting the operation of the applicator;
An illumination step of irradiating the surface of the solder material applied to the mask with inspection light;
Based on the detection result obtained in the detection step, an imaging step of imaging the surface of the solder material applied to the mask under the inspection light irradiated in the illumination step;
A deterioration degree determination step of determining a deterioration degree of the solder material based on a captured image picked up in the imaging step.   A solder material deterioration degree determination program for operating the solder material deterioration degree determination device according to any one of claims 1 to 3, wherein the computer functions as each of the above means.   A solder printing program for operating the solder printing machine according to any one of claims 4 to 7, wherein the computer functions as the above-described means. The recording medium which recorded the program of Claim 10 or 11 so that computer reading was possible.