Method for simply evaluating color difference of knitted fabric

Abstract

The invention provides a method for simply evaluating color difference of knitted fabric, which comprises the following steps: (1) sampling to-be-tested cloth to obtain to-be-tested sample cloth; reading the color difference value and the comprehensive color difference value of each piece of sample cloth to be detected by adopting a color photometer; (2) performing data conversion on the color phase difference values obtained in the step (1) to obtain hue evaluation key data of each piece of to-be-tested sample cloth; (3) calculating the range of the hue evaluation key data obtained in the step (2), and calculating the average value of the comprehensive color difference values obtained in the step (1); and analyzing and evaluating the color difference of the cloth according to the range and the average value. The method provided by the invention has the characteristics of simplicity, convenience and practical operability, data is objectively and scientifically measured and converted and analyzed by using an instrument, the original mass data analysis is greatly simplified, the time of related personnel is saved, and the influence of subjective factors of human eye evaluation between delivery and receiving is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of textile production, and relates to a method for simply evaluating the color difference of knitted fabrics, and specifically to a method for simply evaluating the color difference of each piece of knitted fabric in a dyeing cylinder. Background Art

[0002] In the textile printing and dyeing industry, taking knitted fabrics as an example, after the fibers are woven into cloth through knitting, multiple pieces of cloth are connected end to end together into a rope-like shape and dyed through a dyeing machine (dyeing vat). The dyed cloth needs to be inspected by the printing and dyeing factory for quality evaluation of the dyeing effect.

[0003] Defects on dyed fabrics are divided into obvious defects and unobvious defects. Obvious defects are called dyeing spots, which means that after the dye is dyed on the fiber, the color is obviously uneven. Quality control personnel can directly distinguish local dyeing spots with human eyes. However, for unobvious defects, quality control personnel cannot immediately distinguish the color difference. However, if all the fabrics in the dyeing machine (dyeing vat) are cut and arranged at the head and tail for unified evaluation, the color difference between the pieces (pair difference) and the obvious color difference between the head and tail of a single piece of fabric (color difference) can be distinguished. If fabrics with pair difference or color difference are made into garments, it will lead to a high rate of customer complaints about color difference, thus affecting production quality.

[0004] In the printing and dyeing process of a printing and dyeing factory, the weight of a piece of cloth is generally about 30kg. If the dyeing machine (dyeing vat) can produce 300kg (that is, about 10 pieces of cloth), during the dyeing effect evaluation process, it is necessary to cut the head and tail of each piece of cloth to evaluate the color difference. There are 20 color samples arranged in two rows, and the human eye can barely evaluate the color difference of all pieces. However, if a dyeing vat produces 4800KG or even higher load, the head and tail color samples of the whole vat will be as high as 320 color samples. Because there are too many color samples, the human eye will not be able to fully evaluate the effect together, and visual fatigue is prone to occur. In addition, the objective differences and subjective assumptions of individual vision between people make it easy for the customer quality control personnel responsible for receiving the goods to disagree with the quality management personnel of the printing and dyeing factory responsible for shipment on the color difference issue, which will seriously affect the production and shipment of textiles.

[0005] In order to resolve the disagreement, it is usually necessary to refer to the fastness quality test evaluation report and introduce a third party to evaluate the test results of an authoritative organization. Although this method can solve the disagreement caused by human error, it requires the introduction of a third party, which increases the production cost and time cost of the fabric. Therefore, it is necessary to provide a simple method to accurately and instantly evaluate the color difference of knitted fabrics. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for simply evaluating the color difference of knitted fabrics. The method can simply evaluate the color difference of each piece of fabric in a dye vat and the color difference of different positions of the same piece of fabric through a colorimeter; the method can evaluate the color difference results of the fabric in a more objective, scientific and data-based manner.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] The present invention provides a method for simply evaluating the color difference of knitted fabrics, the method comprising the following steps:

[0009] (1) sampling the cloth to be tested to obtain a sample cloth to be tested; and then using a colorimeter to read the hue difference value and the comprehensive color difference value of each of the sample cloths to be tested;

[0010] (2) performing data conversion on the hue difference values ​​obtained in step (1) to obtain key data for hue evaluation of each of the sample fabrics to be tested;

[0011] (3) Calculate the range of the key data for hue evaluation obtained in step (2), and calculate the average value of the comprehensive color difference value obtained in step (1); and then analyze and evaluate the color difference of the cloth based on the range and the average value.

[0012] The present invention further reduces the calculation difficulty at the detection site by converting the complex data read by the colorimeter into key data for hue evaluation, and realizes a simpler, scientific and data-based accurate evaluation of the color difference results of the cloth.

[0013] Preferably, the colorimeter in step (1) comprises a Datacolor SF600X colorimeter.

[0014] As a preferred technical solution of the present invention, the hue difference value in step (1) includes a lightness difference value, a color saturation difference value and a color hue difference value.

[0015] As a preferred technical solution of the present invention, the data conversion in step (2) includes:

[0016] (a) When -0.09≤hue difference value<0.09, the key data of hue evaluation is recorded as 5;

[0017] (b) When -0.81≤hue difference value<-0.63, the key data of hue evaluation is recorded as number 1;

[0018] (c) When -0.63≤hue difference value<-0.45, the key data of hue evaluation is recorded as number 2;

[0019] (d) When -0.45≤hue difference value<-0.27, the key data of hue evaluation is recorded as number 3;

[0020] (e) When -0.27≤hue difference<-0.09, the key data for hue evaluation is recorded as 4;

[0021] (f) When 0.09≤hue difference<0.27, the key data of hue evaluation is recorded as 6;

[0022] (g) When 0.27≤hue difference<0.45, the key data of hue evaluation is recorded as 7;

[0023] (h) When 0.45≤hue difference<0.63, the key data of hue evaluation is recorded as 8;

[0024] (i) When 0.63≤hue difference value<0.81 is specified, the key data for hue evaluation is recorded as number 9.

[0025] As a preferred technical solution of the present invention, when the hue difference value is specified to be less than -0.81, the hue evaluation key data is recorded as "-".

[0026] Preferably, when the hue difference value is greater than 0.81, the hue evaluation key data is recorded as "+".

[0027] It is worth noting that the method of the present invention is a simplified summary of multiple color difference data, which can simply and intuitively reflect the color difference distribution of each cloth head and tail in a whole cylinder, that is, convert the actual hue difference value read by the colorimeter into simple digits. Its working principle is as follows: in the process of digital calculation, addition and subtraction within 10 are the simplest, and the middle of the numbers 1 to 9 is 5, and the remaining 1, 2, 3, 4 and 6, 7, 8, 9 are evenly distributed on both sides of 5; first, the specific values ​​of the hue difference value (brightness difference, color saturation difference and color hue difference) of the color difference of a cylinder of cloth are read by the Datacolor SF600X colorimeter, and then the data distribution principle in mathematical statistics is used to convert the many specific values ​​of the hue difference value (-0.81 to 0.81) into numbers 1 to 9 according to the Tolerances tolerance standard range of the specified range, a total of 9 data simplification ranges, that is, the key data for hue evaluation in step (2).

[0028] As a preferred technical solution of the present invention, the key data for hue evaluation in step (2) include DL, DC and DH.

[0029] As a preferred technical solution of the present invention, the DL is the key data for hue evaluation obtained by data conversion of the lightness difference.

[0030] Preferably, the DC is key data for hue evaluation obtained by data conversion of color saturation difference.

[0031] Preferably, the DH is key data for hue evaluation obtained by data conversion of color hue difference.

[0032] As a preferred technical solution of the present invention, the extreme difference in step (3) includes the extreme difference in brightness, the extreme difference in color saturation and the extreme difference in color hue.

[0033] As a preferred technical solution of the present invention, the calculation formula of the brightness extreme difference is: △DL=DL maximum value-DL minimum value.

[0034] Preferably, the calculation formula for the color saturation extreme difference is: ΔDC=DC maximum value-DC minimum value.

[0035] Preferably, the calculation formula for the color hue extreme difference is: △DH=DH maximum value-DH minimum value.

[0036] As a preferred technical solution of the present invention, the evaluation criteria for the cloth color difference in step (3) include:

[0037] (i) When △DL≤2, △DC≤1, △DH≤1 and the average value of the comprehensive color difference value is ≤0.1, the cloth is judged to be of good quality;

[0038] (ii) When △DL≤4, △DC=2, △DH=2 and the average value of the comprehensive color difference is 0.1~0.16, the cloth is judged to be of qualified quality.

[0039] As a preferred technical solution of the present invention, the evaluation criteria for cloth color difference also include: when the key data for hue evaluation is "-" or "+", the cloth quality is judged to be unqualified.

[0040] It is worth noting that in addition to the above-mentioned evaluation criteria, the criteria for judging whether the cloth quality is unqualified also include: (1) △DL>4; (2) △DC>2; (3) △DH>2; (4) the average value of the comprehensive color difference value is>0.2; as long as any one of the above conditions is met, the cloth quality can be judged to be unqualified.

[0041] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The method provided by the present invention is simple and practical. The present invention uses instruments to objectively and scientifically measure data and convert and analyze them, which greatly simplifies the original large amount of data analysis, saves time for related personnel, and reduces the influence of subjective factors of human visual evaluation between shipment and receipt. DETAILED DESCRIPTION

[0044] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0045] As a specific implementation method of the present invention, the present invention provides a method for simply evaluating the color difference of knitted fabrics, the method comprising the following steps:

[0046] (1) sampling the cloth to be tested to obtain a sample cloth to be tested; and then using a colorimeter to read the hue difference value and the comprehensive color difference value of each of the sample cloths to be tested;

[0047] The hue difference value includes the brightness difference value, the color saturation difference value and the color hue difference value;

[0048] (2) performing data conversion on the hue difference values ​​obtained in step (1) to obtain key data for hue evaluation of each of the sample fabrics to be tested;

[0049] Wherein, the data conversion includes: (a) when -0.09≤hue difference value<0.09, the hue evaluation key data is recorded as the number 5;

[0050] (b) When -0.81≤hue difference value<-0.63, the key data of hue evaluation is recorded as number 1;

[0051] (c) When -0.63≤hue difference value<-0.45, the key data of hue evaluation is recorded as number 2;

[0052] (d) When -0.45≤hue difference value<-0.27, the key data of hue evaluation is recorded as number 3;

[0053] (e) When -0.27≤hue difference<-0.09, the key data for hue evaluation is recorded as 4;

[0054] (f) When 0.09≤hue difference<0.27, the key data of hue evaluation is recorded as 6;

[0055] (g) When 0.27≤hue difference<0.45, the key data of hue evaluation is recorded as 7;

[0056] (h) When 0.45≤hue difference<0.63, the key data of hue evaluation is recorded as 8;

[0057] (i) When 0.63≤hue difference value<0.81, the key data of hue evaluation is recorded as 9;

[0058] (j) When the hue difference value is less than -0.81, the hue evaluation key data is recorded as "-";

[0059] (k) When the hue difference value is greater than 0.81, the hue evaluation key data is recorded as "+";

[0060] The hue evaluation key data includes: hue evaluation key data DL obtained by data conversion of lightness difference, hue evaluation key data DC obtained by data conversion of color saturation difference, and hue evaluation key data DH obtained by data conversion of color hue difference, recorded as [DL, DC, DH];

[0061] (3) calculating the range of the key data for hue evaluation obtained in step (2), and calculating the average value (denoted as DE) of the comprehensive color difference value obtained in step (1); and then analyzing and evaluating the color difference of the cloth according to the range and the average value;

[0062] The range includes: brightness range, color saturation range and color hue range;

[0063] The evaluation criteria for the color difference of the cloth include: (i) when △DL≤2, △DC≤1, △DH≤1 and the average value of the comprehensive color difference value is ≤0.1, the cloth quality is judged to be excellent; (ii) when △DL≤4, △DC=2, △DH=2 and the average value of the comprehensive color difference value is 0.1-0.16, the cloth quality is judged to be qualified; (iii) when the key data of hue evaluation is "-" or "+", or satisfies any one of △DL>4, △DC>2, △DH>2 or the average value of the comprehensive color difference value is>0.2, the cloth quality is judged to be unqualified.

[0064] Example 1

[0065] This embodiment provides a method for simply evaluating the color difference of knitted fabrics, the method comprising the following steps:

[0066] (1) Sampling the cloth to be tested to obtain a sample cloth to be tested; and then using a colorimeter to read the hue difference value and the comprehensive color difference value of each of the sample cloths to be tested, as shown in Table 1;

[0067] The sample cloths to be tested are taken from the same piece of cloth, and the spacing between each piece of sample cloth to be tested is 10 cm.

[0068] (2) performing data conversion on the hue difference values ​​obtained in step (1) to obtain key data for hue evaluation of each of the sample fabrics to be tested, as shown in Table 1;

[0069] (3) Calculate the range of the key data for hue evaluation obtained in step (2), and calculate the average value of the comprehensive color difference value obtained in step (1); and then analyze and evaluate the color difference of the cloth based on the range and the average value.

[0070] Table 1

[0071]

[0072] According to Table 1, △DL=6-4=2, △DC=5-5=0, △DH=0, and the average value of the comprehensive color difference value=0.082<0.1; therefore, the cloth provided in this embodiment is of excellent quality.

[0073] Example 2

[0074] This embodiment provides a method for simply evaluating the color difference of knitted fabrics, and the method is different from that of Embodiment 1 only in that:

[0075] In this embodiment, the sample cloths to be tested in step (1) are adjusted to be taken from different cloths in the same dye vat, wherein samples 1-8 are taken from the head and tail of different cloths respectively; and samples 9-14 are taken from different positions of the same cloth.

[0076] The hue difference value, comprehensive color difference value and hue evaluation key data of the sample cloth to be tested provided in this embodiment are shown in Table 2.

[0077] Table 2

[0078]

[0079] According to Table 2, △DL=7-3=4, △DC=6-4=2, △DH=6-4=2, and the average value of the comprehensive color difference value=0.157; therefore, it can be determined that the quality of the cloth provided in this embodiment is qualified.

[0080] Example 3

[0081] This embodiment provides a method for simply evaluating the color difference of knitted fabrics, and the method is different from that of Embodiment 1 only in that:

[0082] In this embodiment, the sample cloth to be tested in step (1) is adjusted to be taken from different cloths in a dye vat, wherein samples 1-12 are taken from the head and tail of different cloths respectively.

[0083] The hue difference values ​​and key data for hue evaluation of the sample cloth to be tested provided in this embodiment are shown in Table 3.

[0084] Table 3

[0085]

[0086]

[0087] According to Table 3, the key data of hue evaluation obtained in this embodiment shows "-", therefore, it is determined that the quality of the cloth provided by this embodiment is unqualified.

[0088] The color difference of the cloth provided in the above Examples 1-3 was evaluated by a third-party evaluation authority GSI, and the evaluation results were the same as the results of the method of the present invention, further proving the practicality, effectiveness and accuracy of the method of the present invention.

[0089] Comparative Example 1

[0090] This comparative example provides a method for evaluating the color difference of knitted fabrics, which differs from Example 1 only in that:

[0091] This comparative example omits step (2) and step (3), that is, this comparative example evaluates the color difference of the cloth by analyzing the hue difference value and the comprehensive color difference value of the sample cloth to be tested.

[0092] Compared with Example 1, the method provided in this comparative example requires the analysis of a large amount of data, the workload is complicated and time-consuming, and is not conducive to the rapid and accurate evaluation of the color difference of the cloth.

[0093] In summary, the method provided by the present invention is simple and practical. The present invention uses instruments to objectively and scientifically measure data and convert and analyze them, which greatly simplifies the original large amount of data analysis, saves the time of relevant personnel, and reduces the influence of subjective factors of human visual evaluation between shipment and receipt.

[0094] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for simply evaluating the color difference of knitted fabrics, characterized in that: The method comprises the following steps: (1) sampling the cloth to be tested to obtain a sample cloth to be tested; and then using a colorimeter to read the hue difference value and the comprehensive color difference value of each of the sample cloths to be tested; (2) performing data conversion on the hue difference values ​​obtained in step (1) to obtain key data for hue evaluation of each of the sample fabrics to be tested; (3) Calculate the range of the key data for hue evaluation obtained in step (2), and calculate the average value of the comprehensive color difference value obtained in step (1); and then analyze and evaluate the color difference of the cloth based on the range and the average value.

2. The method according to claim 1, characterized in that: The hue difference value in step (1) includes lightness difference value, color saturation difference value and color hue difference value.

3. The method according to claim 1 or 2, characterized in that: The data conversion in step (2) includes: (a) When -0.09≤hue difference value<0.09, the key data of hue evaluation is recorded as 5; (b) When -0.81≤hue difference value<-0.63, the key data of hue evaluation is recorded as number 1; (c) When -0.63≤hue difference value<-0.45, the key data of hue evaluation is recorded as number 2; (d) When -0.45≤hue difference value<-0.27, the key data of hue evaluation is recorded as number 3; (e) When -0.27≤hue difference<-0.09, the key data for hue evaluation is recorded as 4; (f) When 0.09≤hue difference<0.27, the key data of hue evaluation is recorded as 6; (g) When 0.27≤hue difference<0.45, the key data of hue evaluation is recorded as 7; (h) When 0.45≤hue difference<0.63, the key data of hue evaluation is recorded as 8; (i) When 0.63≤hue difference value<0.81 is specified, the key data for hue evaluation is recorded as number 9.

4. The method according to claim 3, characterized in that: When the hue difference value is specified to be less than -0.81, the hue evaluation key data is recorded as "-"; Preferably, when the hue difference value is specified to be greater than 0.81, the hue evaluation key data is recorded as "+".

5. The method according to any one of claims 1 to 4, characterized in that: The key data for hue evaluation in step (2) include DL, DC and DH.

6. The method according to claim 5, characterized in that The DL is the key data for hue evaluation obtained by data conversion of the lightness difference; Preferably, the DC is the key data for hue evaluation obtained by data conversion of the color saturation difference; Preferably, the DH is key data for hue evaluation obtained by data conversion of color hue difference.

7. The method according to any one of claims 1 to 6, characterized in that: The extreme differences in step (3) include brightness extreme differences, color saturation extreme differences, and color hue extreme differences.

8. The method according to claim 7, characterized in that The calculation formula of the brightness extreme difference is: △DL=DL maximum value-DL minimum value; Preferably, the calculation formula of the color saturation extreme difference is: △DC=DC maximum value-DC minimum value; Preferably, the calculation formula for the color hue extreme difference is: △DH=DH maximum value-DH minimum value.

9. The method according to any one of claims 1 to 8, characterized in that: The evaluation criteria for the cloth color difference in step (3) include: (i) When △DL≤2, △DC≤1, △DH≤1 and the average value of the comprehensive color difference value is ≤0.1, the cloth is judged to be of good quality; (ii) When △DL≤4, △DC=2, △DH=2 and the average value of the comprehensive color difference is 0.1~0.16, the cloth is judged to be of qualified quality.

10. The method according to claim 9, characterized in that The evaluation criteria for the color difference of the cloth preferably include: when the key data for hue evaluation is "-" or "+", the cloth quality is judged to be unqualified.

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