A color paste matching system

Abstract

This invention discloses a color paste mixing system, including a color mixing tank, several material tanks, a metering pump, a stirring motor, an output pump, and a three-way solenoid valve, each corresponding to one of the material tanks. The input end of each metering pump is connected to the outlet of the corresponding material tank via a pipe, and the output end of each metering pump is connected to a conveying pipe. The outlet end of the conveying pipe is connected to the inlet of the color mixing tank. The stirring motor is fixedly installed on the top of the color mixing tank, and the output shaft of the stirring motor is connected to the stirring component located in the inner cavity of the color mixing tank.

Description

Technical Field

[0001] This invention relates to the field of color paste formulation technology, and more specifically, to a color paste matching system. Background Technology

[0002] In industries such as printing, coatings, textile dyeing, and ink production, color paste matching is a core process that determines the color quality of the final product. The accuracy, efficiency, and batch consistency of color matching directly affect the product yield and production efficiency. Manual matching relies on the experience of operators and suffers from low color matching accuracy, large batch color differences, and low matching efficiency, which cannot meet the needs of large-scale, high-precision industrial production. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a color paste matching system.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] This invention discloses a color paste mixing system, including a color mixing tank, several material tanks, a metering pump, a stirring motor, an output pump, and a three-way solenoid valve, each corresponding to one of the material tanks. The input end of each metering pump is connected to the outlet of the corresponding material tank via a pipe, and the output end of each metering pump is connected to a conveying pipe. The outlet end of the conveying pipe is connected to the inlet of the color mixing tank. The stirring motor is fixedly installed on the top of the color mixing tank, and the output shaft of the stirring motor is connected to a stirring component located inside the color mixing tank. The input end of the output pump is connected to the color mixing tank via a pipe, and the output end of the output pump is connected to one port of the three-way solenoid valve. The other two ports of the three-way solenoid valve are respectively connected to an output pipe and a drain pipe.

[0006] Furthermore, it also includes a transfer pump and a buffer tank. The input end of the transfer pump is connected to the outlet of the color mixing tank through a pipe, and the output end of the transfer pump is connected to the inlet of the buffer tank through a pipe.

[0007] Preferably, a check valve and a filter are installed in series on the pipeline connecting the metering pump and the corresponding material tank, with the check valve flowing from the material tank to the metering pump.

[0008] Preferably, the material tank includes four color paste tanks, one colorless concentrate tank, and one cleaning solution tank; the four color paste tanks contain cyan C color paste, magenta M color paste, yellow Y color paste, and black K color paste respectively; the colorless concentrate tank contains colorless concentrate for diluting the color pastes; and the cleaning solution tank contains cleaning solution for cleaning equipment pipelines.

[0009] Preferably, both the top of the color mixing tank and the top of the buffer tank are connected to a vacuum degassing pipe. The color mixing tank and the buffer tank share the same vacuum degassing pipe, which is used to connect to an external vacuum system to perform vacuum degassing treatment inside the tank.

[0010] Preferably, the system also includes a controller, which is electrically connected to the metering pump, stirring motor, transfer pump, output pump, and three-way solenoid valve. The controller has a pre-set stirring time adjustment module, which calculates the total material quantity based on the total amount of color paste and colorless raw liquid output by the metering pump, and generates the target stirring time for the stirring motor based on the type and quantity of color paste used for color mixing. The controller controls the running time of the stirring motor according to the target stirring time.

[0011] As a preferred option, the formula for calculating the target stirring time is:

[0012]

[0013] in, To preset the basic mixing time, This is the material quantity weighting coefficient. This refers to the total mass of the colorant and colorless stock solution used in this preparation. This is the color number weighting coefficient. This refers to the types and quantities of colorants used in this color matching. This is the weighting coefficient for the total proportion of pigments. This represents the percentage of the total mass of all colorants used in this color matching.

[0014] As a preferred option, a preset basic mixing time is used. The calibration algorithm is

[0015]

[0016] in, The rated effective volume of the color mixing tank. The length of the agitator blades. This refers to the rated operating speed of the mixing motor. It is the calibration constant for the basic duration, a fixed calibration value determined based on experiments on the uniformity of the stirred flow field.

[0017] As a preferred option, the material quantity weighting coefficient The calibration algorithm is

[0018]

[0019] in, The reference viscosity for the mixing system of the coloring materials used in this experiment is calculated by weighting the average viscosity of each base color paste used in this experiment with the viscosity of the colorless stock solution according to their mass ratio. is the calibration constant for the material quantity coefficient, which is a fixed calibration value determined based on experiments on the material dispersion characteristics.

[0020] As a preferred option, the color number weighting coefficient The calibration algorithm is

[0021]

[0022] in, This represents the maximum density difference between the base colorants used in this color matching. It is the calibration constant for the color number coefficient, a fixed calibration value determined based on the experiment of the uniformity of multicolor paste mixing.

[0023] As a preferred option, the weighting coefficient of the total proportion of pigments The calibration algorithm is

[0024]

[0025] in, The average viscosity of each base colorant used in this color matching. The base viscosity for the colorless stock solution is... This is the calibration constant for the pigment proportion coefficient, a fixed calibration value determined based on experiments on the viscosity characteristics of the mixed system.

[0026] A method for color mixing with pigments includes the following steps:

[0027] a. Pre-cleaning process: The metering pump connected to the cleaning solution tank starts and quantitatively delivers cleaning solution into the color mixing tank. The stirring motor drives the stirring components to rotate, cleaning the inner cavity of the color mixing tank and the stirring components. After cleaning, the transfer pump starts and transfers the cleaning solution in the color mixing tank to the buffer tank to clean the inner cavity of the buffer tank. After cleaning, the output pump starts and the three-way solenoid valve switches to the position connected to the drain pipe, discharging all the waste liquid after cleaning through the drain pipe.

[0028] b. Precision color matching process: Based on the color matching formula of the target color paste, determine the amount of each color paste and the amount of colorless stock solution. The metering pumps connected to the corresponding color paste tank and colorless stock solution tank are started respectively to quantitatively output the corresponding color paste and colorless stock solution into the color mixing tank. After the material is conveyed, the stirring motor drives the stirring components to fully and evenly mix the color paste and colorless stock solution in the tank to obtain the target color paste. After mixing, the transfer pump is started to transfer all the target color paste in the color mixing tank to the buffer tank for later use.

[0029] c. Finished product output process: When the target pigment is needed, the output pump is started, the three-way solenoid valve is switched to the position connected to the output pipe, and the target pigment in the buffer tank is quantitatively output to the use position through the output pipe;

[0030] d. Color change and remixing process: When it is necessary to change the color formula of the target pigment, repeat steps a to c to complete the mixing and output of the new pigment formula.

[0031] Preferably, in step b, the amount of colorless stock solution used is determined by the following calculation formula:

[0032] Colorless stock solution dosage ratio = (number of colors × 100 - sum of sub-color percentages × 100) / 100;

[0033] The color number refers to the number of different types of pigments used in the color formula of the target pigment, and the sum of the sub-color proportions is the sum of the mass percentage values ​​of each color pigment in the color formula.

[0034] Preferably, in step b, while stirring and mixing, the inner cavity of the color mixing tank and the buffer tank is vacuum degassed through a vacuum system connected to the vacuum degassing pipe to remove air bubbles from the color paste.

[0035] The beneficial effects of this invention are: by using a metering pump, precise quantitative delivery of CMYK four-color base pigments and colorless stock solution is achieved; combined with the formula for calculating the amount of colorless stock solution, dual precise control of pigment color and concentration is achieved, solving the problems of color difference and batch inconsistency caused by manual mixing.

[0036] Before color matching, the color mixing tank, buffer tank and corresponding pipelines are cleaned in a closed loop to ensure no color residue contamination and guarantee the purity of different color formulas. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a color paste mixing system in this embodiment;

[0038] Figure 2 This is a top view of the color paste mixing system in this embodiment;

[0039] Figure 3 This is a partial structural diagram of the color paste matching system in this embodiment.

[0040] Attached reference numerals: 1. Material tank; 2. One-way valve; 3. Metering pump; 4. Delivery pipe; 5. Color mixing tank; 6. Stirring motor; 7. Buffer tank; 8. Output pump; 9. Three-way solenoid valve; 10. Output pipe; 11. Drain pipe; 12. Vacuum degassing pipe; 13. Color paste tank; 14. Colorless stock solution tank; 15. Cleaning solution tank; 16. Transfer pump; 17. Filter. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] like Figures 1-3 As shown, a color paste mixing system includes a color mixing tank 5, several material tanks 1, a metering pump 3 corresponding to each material tank 1, a stirring motor 6, a transfer pump 16, a buffer tank 7, an output pump 8, a three-way solenoid valve 9, and a controller.

[0043] In this embodiment, there are a total of 6 material tanks 1, and 6 high-precision servo metering pumps 3 are set accordingly. The metering accuracy of the metering pumps 3 is ±0.1%, which ensures the accuracy of material delivery. The 6 material tanks 1 specifically include four color paste tanks 13, one colorless stock solution tank 14, and one cleaning solution tank 15. The four color paste tanks 13 contain cyan C color paste, magenta M color paste, yellow Y color paste, and black K color paste, respectively, which constitute the CMYK four-color basic color system. The colorless stock solution tank 14 contains colorless stock solution used to dilute the color paste. The cleaning solution tank 15 contains an environmentally friendly cleaning solution that is compatible with the color paste system.

[0044] The input end of each metering pump 3 is connected to the outlet of the corresponding material tank 1 through a pipe. On the pipe connecting the metering pump 3 and the corresponding material tank 1, a one-way valve 2 and a filter 17 are installed in series. The one-way valve 2 is directed from the material tank 1 to the metering pump 3 to prevent material backflow and ensure metering accuracy. The filter 17 uses a 5μm precision filter element to filter particulate impurities in the material and avoid clogging the metering pump and the pipeline. The output end of each metering pump 3 is connected to a conveying pipe 4. The outlet end of all conveying pipes 4 is connected to the top inlet of the color mixing tank 5.

[0045] The stirring motor 6 is fixedly installed at the top center of the color mixing tank 5. The output shaft of the stirring motor 6 extends downward into the inner cavity of the color mixing tank 5. The end of the output shaft is fixedly connected to a stirring component. In this embodiment, the stirring component adopts a three-layer stirring paddle, which can realize the up-and-down circulation stirring of the material in the tank, improve the mixing uniformity, and shorten the mixing time. The color mixing tank 5 adopts a small volume design with a rated effective volume of 5L, which is suitable for small batch and multiple batch color mixing needs.

[0046] The input end of the transfer pump 16 is connected to the bottom outlet of the color mixing tank 5 through a pipe, and the output end of the transfer pump 16 is connected to the top inlet of the buffer tank 7 through a pipe. The rated effective volume of the buffer tank 7 is 10L, which is used to buffer the target color paste after preparation, so as to realize continuous production of preparation and use at the same time. The input end of the output pump 8 is connected to the bottom outlet of the buffer tank 7 through a pipe, and the output end of the output pump 8 is connected to the liquid inlet of the three-way solenoid valve 9. The two liquid outlets of the three-way solenoid valve 9 are respectively connected to the output pipe 10 and the drain pipe 11. The output pipe 10 is used to connect to the downstream use station, and the drain pipe 11 is used to discharge the cleaning waste liquid.

[0047] Both the top of the color mixing tank 5 and the top of the buffer tank 7 are connected to a vacuum degassing pipe 12. The color mixing tank 5 and the buffer tank 7 share the same vacuum degassing pipe 12. The end of the vacuum degassing pipe 12 is connected to an external vacuum system, which can perform vacuum degassing treatment inside the tank during the mixing and buffering process.

[0048] The controller adopts a PLC programmable controller, which is electrically connected to metering pump 3, stirring motor 6, transfer pump 16, output pump 8 and three-way solenoid valve 9 to realize the full-process automated control. The controller has a built-in stirring time adjustment module, which has a built-in stirring time calculation unit. It uses a linear adaptive algorithm to calculate the target stirring time, and also has built-in calibration algorithms for each weight coefficient and the base time to achieve accurate matching of parameters.

[0049] In this embodiment, each calibration constant was calibrated through previous experiments, and the specific values ​​are as follows:

[0050] Basic duration calibration constant The value is 120 s·m·r / (L·min); material quantity coefficient calibration constant. The value is 0.05 s / (kg·mPa·s); the chromatic number coefficient calibration constant. The value is 8s / (seed·g / cm³); the calibration constant for the pigment proportion coefficient. The value is 0.1s / percentage unit.

[0051] Example 1: Four-color formula color matching, the specific steps are as follows:

[0052] Step a. Pre-cleaning process

[0053] The metering pump 3, connected to the cleaning solution tank 15, is started, delivering 2L of cleaning solution to the color mixing tank 5. The stirring motor 6 rotates at 600r / min for 30s to flush and clean the inner cavity and stirring components of the color mixing tank 5. After cleaning, the transfer pump 16 is started, transferring all the cleaning solution in the color mixing tank 5 to the buffer tank 7. The buffer tank 7 is left to stand for 20s to clean its inner cavity. After cleaning, the output pump 8 is started, and the three-way solenoid valve 9 is switched to the position connected to the drain pipe 11, discharging all the waste liquid after cleaning through the drain pipe 11, thus completing the pre-cleaning of the pipeline.

[0054] Step b. Color matching process

[0055] The color formula of the target pigment is: C=10%, M=3%, Y=8%, K=1%, that is, the number of pigment types used is N=4, and the sum of the proportions of sub-colors is 22.

[0056] First, calculate the ratio of colorless stock solution dosage using the formula:

[0057] The ratio of colorless stock solution dosage is (4×100-22×100) / 100=378%;

[0058] Set the total material mass for this color scheme. If the weight is 4 kg, then the amounts of each material are: C color paste 0.1 kg, M color paste 0.03 kg, Y color paste 0.08 kg, K color paste 0.01 kg, and colorless stock solution 3.78 kg;

[0059] The metering pumps 3 connected to the corresponding color paste tank 13 and colorless stock solution tank 14 are started respectively, and the corresponding materials are quantitatively output into the color mixing tank 5;

[0060] After the material delivery is completed, the controller calculates the relevant parameters for this color matching:

[0061] Rated effective volume of color mixing tank 5 For a capacity of 5L, the length of the agitator blades is... The depth is 0.08m, and the rated operating speed of the stirring motor is 6. The preset basic mixing time is 800 r / min.

[0062]

[0063] The average viscosity of the base color paste used in this study The standard viscosity of the colorless stock solution is 250 mPa·s. The reference viscosity of the mixed system is 50 mPa·s. Given a Pa·s of 55 mPa, calculate the material quantity weighting factor:

[0064]

[0065] The maximum density difference of each base colorant used in this study It is 0.2 g / cm³ 3 Calculate the color number weighting coefficient:

[0066]

[0067] Calculate the weighting coefficient of the total proportion of pigments:

[0068]

[0069] The total percentage of pigment in this experiment is S=22. Substituting this value into the core formula, the target total mixing time is calculated as follows:

[0070] The controller controls the stirring motor 6 to run continuously at a speed of 800 r / min for 71 seconds. At the same time, through the vacuum degassing pipe 12 connected to the external vacuum system, synchronous vacuum degassing is performed at a vacuum degree of -0.08 MPa to ensure that the materials in the tank are fully and uniformly mixed to obtain the target color paste. After the mixing is completed, the transfer pump 16 is started to transfer all the target color paste in the color mixing tank 5 to the buffer tank 7 for buffering and later use.

[0071] Step c. Finished product output process

[0072] When the target color paste is needed, the output pump 8 starts, and the three-way solenoid valve 9 switches to the position connected to the output pipe 10, so that the target color paste in the buffer tank 7 is quantitatively output to the downstream printing press station through the output pipe 10, realizing continuous production of mixing and use at the same time.

[0073] Step d. Color change and remixing process

[0074] When it is necessary to change the color formula of the target pigment, repeat steps a to c. First, thoroughly clean the entire pipeline, and then mix and output the new pigment formula to avoid cross-contamination between different colors.

[0075] Example 2: Color matching for a single-color formula, the specific steps are as follows:

[0076] Step a is the same as in Example 1;

[0077] Step b. Color matching process

[0078] The target color paste formula is: C=0, M=0, Y=0, K=50%, meaning the number of color paste types used is N=1, and the sum of the proportions of the sub-colors is 50. First, the proportion of colorless stock solution is calculated using the formula for calculating the amount of colorless stock solution: Colorless stock solution proportion = (1×100-50×100) / 100 = 50%.

[0079] Set the total material mass for this color scheme. If the weight is 2kg, then the amount of each material used is: 1kg of K color paste and 1kg of colorless stock solution.

[0080] Metering pumps 3, which are connected to the corresponding color paste tank 13 and colorless stock solution tank 14, are started respectively, and the corresponding materials are quantitatively output into the color mixing tank 5; after the material is transported, the controller calculates the relevant parameters of this color mixing.

[0081] Preset basic mixing time It is 9.375s.

[0082] K color paste viscosity The standard viscosity of the colorless stock solution is 300 mPa·s. The reference viscosity of the mixed system is 50 mPa·s. Given a Pa·s of 175 mPa, calculate the material quantity weighting factor:

[0083]

[0084] Monochromatic formulations have no density difference. If the value is 0, calculate the color number weighting coefficient:

[0085]

[0086] Calculate the weighting coefficient of the total proportion of pigments:

[0087]

[0088] The total percentage of pigment in this experiment is S=50. Substituting this value into the core formula, the target total mixing time is calculated as follows:

[0089]

[0090] The controller controls the stirring motor 6 to run continuously at a speed of 800 r / min for 65 seconds, and simultaneously performs vacuum degassing. After the mixing and blending are completed, the target color paste is transported to the buffer tank 7 for later use.

[0091] Steps c and d are the same as in Example 1.

[0092] By using a basic time calibration algorithm based on the mixing tank volume, mixing component size, and motor speed, as well as a weighted coefficient calibration algorithm based on material viscosity, density, and proportion, the mixing time can be accurately and adaptively matched. This completely solves the problem of poor adaptability of fixed mixing time, ensuring the uniformity of color paste mixing while avoiding ineffective mixing and improving production efficiency.

[0093] It achieves fully automatic and precise color matching of pigments, with high color matching accuracy, good batch consistency, and the stirring time can be adaptively adjusted according to equipment parameters and material characteristics. It has high mixing uniformity, convenient color change and cleaning, and less raw material waste, completely solving the pain points of existing technologies.

[0094] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A colorant dispensing system, characterized by, Including color matching stirring tank (5), several material barrels (1), and the metering pump (3) that is set up one to one with the material barrel (1) correspondingly, stirring motor (6), output pump (8) and three-way electromagnetic valve (9);The input end of each metering pump (3) is connected with the corresponding material barrel (1) through pipeline, and the output end of each metering pump (3) is connected with the conveying pipe (4), and the discharge end of the conveying pipe (4) is connected with the color matching stirring tank (5) in communication;The stirring motor (6) is fixedly installed on the top of the color matching stirring tank (5), and the output shaft of the stirring motor (6) is drivingly connected with the stirring part located in the inner cavity of the color matching stirring tank (5);The input end of the output pump (8) is connected with the color matching stirring tank (5) through pipeline, and the output end of the output pump (8) is connected with one of the ports of the three-way electromagnetic valve (9), and the other two ports of the three-way electromagnetic valve (9) are connected with the output pipe (10) and the blowdown pipe (11) respectively.

2. A colorant dispensing system according to claim 1, wherein, It also includes a transfer pump (16) and a buffer tank (7), the input end of the transfer pump (16) is connected with the color matching stirring tank (5) through pipeline, and the output end of the transfer pump (16) is connected with the buffer tank (7) through pipeline.

3. The colorant dispensing system of claim 1, wherein, The pipeline connected with the metering pump (3) and the corresponding material barrel (1) is sequentially connected with a check valve (2) and a filter (17), and the conduction direction of the check valve (2) is from the material barrel (1) to the metering pump (3).

4. The colorant dispensing system of claim 1, wherein, The material barrel (1) includes four color paste barrels (13), one colorless stock solution barrel (14) and one cleaning liquid barrel (15);The four color paste barrels (13) respectively contain cyan C color paste, magenta M color paste, yellow Y color paste and black K color paste, and the colorless stock solution barrel (14) contains colorless stock solution for diluting color paste.

5. The colorant dispensing system of claim 1, wherein, The top of the color matching stirring tank (5) and the top of the buffer tank (7) are connected with a vacuum degassing pipe (12), the color matching stirring tank (5) and the buffer tank (7) share the same vacuum degassing pipe (12), and the vacuum degassing pipe (12) is used for connecting a vacuum system to perform vacuum degassing treatment on the tank.

6. The colorant dispensing system of claim 2, wherein, It also includes a controller, the controller (18) is electrically connected with the metering pump (3), the stirring motor (6), the transfer pump (16), the output pump (8), the three-way electromagnetic valve (9) respectively;The controller is provided with a stirring time adjusting module, the stirring time adjusting module calculates the total material quantity according to the total amount of color paste output by the metering pump (3) and the amount of colorless stock solution, and generates the target stirring time of the stirring motor (6) according to the type and number of color paste used for color matching, and the controller controls the running time of the stirring motor (6) according to the target stirring time.

7. A colorant dispensing system according to claim 6, wherein, The calculation formula of target stirring time is wherein, is a preset basic stirring time, is a material weight coefficient, is the total material mass of the colorant and the colorless stock solution for this color matching, is a color number weight coefficient, is the number of colorant types used for this color matching, is a total colorant proportion weight coefficient, is the total mass percentage of all colorants used for this color matching.

8. A colorant dispensing system according to claim 7, wherein, The preset basic stirring duration The calibration algorithm is wherein, is the rated effective volume of the color-matching tank (5), is the length of the paddle of the stirring element, is the rated operating speed of the stirring motor (6), is the base time length calibration constant, a fixed calibration value determined based on stirring flow field uniformity experiments.

9. A method of matching a color paste, characterized by, The color paste color matching system based on any one of claims 1-8 is realized, including the following steps: a. Pre-cleaning process: the metering pump (3) connected with the cleaning liquid barrel (15) is started to quantitatively deliver the cleaning liquid into the color matching stirring tank (5), the stirring motor (6) drives the stirring part to rotate to clean the inner cavity of the color matching stirring tank (5) and the stirring part; after cleaning is completed, the transfer pump (16) is started to deliver the cleaning liquid in the color matching stirring tank (5) into the buffer tank (7) to clean the inner cavity of the buffer tank (7); after cleaning is completed, the output pump (8) is started, and the three-way electromagnetic valve (9) is switched to the position in communication with the drain pipe (11) to completely discharge the waste liquid after cleaning through the drain pipe (11); b. Precise color matching process: according to the color matching formula of the target color paste, the amount of each color paste and the amount of colorless stock solution are determined, and the metering pump (3) connected with the corresponding color paste barrel (13) and colorless stock solution barrel (14) is started to quantitatively output the corresponding color paste and colorless stock solution into the color matching stirring tank (5); after the material delivery is completed, the stirring motor (6) drives the stirring part to make the color paste and colorless stock solution in the tank fully and uniformly mixed to obtain the target color paste; after mixing is completed, the transfer pump (16) is started to completely deliver the target color paste in the color matching stirring tank (5) into the buffer tank (7) for buffering; c. Product output process: when the target color paste is needed, the output pump (8) is started, the three-way electromagnetic valve (9) is switched to the position in communication with the output pipe (10), and the target color paste in the buffer tank (7) is quantitatively output through the output pipe (10); d. Color changing and re-matching process: when the color matching formula of the target color paste needs to be changed, steps a to c are repeated to complete the matching and output of the new formula color paste.

10. The colorant matching method according to claim 9, wherein In step b, the amount of colorless stock solution is determined by the following calculation formula: Colorless stock solution usage ratio = (color number x 100 - sub-color ratio addition value x 100) / 100; Wherein, the color number is the number of color paste types used in the color matching formula of the target color paste, and the sub-color ratio addition value is the sum of the mass percentage values of each color paste in the color matching formula.

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