Button inspection procedures and standards

Views: 73     Author: Site Editor     Publish Time: 2022-11-23      Origin: Site

As a kind of clothing accessories, buttons not only act as connecting parts in clothing, but also can play the role of embellishment and decoration. Resin buttons made of polyester are expensive and suitable for clothing. All kinds of metal buttons are light and not easy to change color, but also can be stamped pattern and clothing manufacturer logo; The texture of shell buttons is elegant, the light color is bright, has been popular with consumers; Crochet and bag buckles made of clothing fabric or near-colored fabric can give clothing ethnic style and craft value. In spite of this, the quality of buttons is also uneven, which requires inspectors to understand the standard at the same time, improve the accuracy and precision of the inspection, so as to pay close attention to the quality of buttons. So how do you check the buttons? This article will give you a detailed introduction to the button test steps and standards, I hope you Xueyou director.

One, button basic inspection method

1. Control sample or confirmation sample. See if the color and model are consistent with the sample;

2, the surface of the button shall not have gaps, cracks, uneven and obvious scratches;

3, face back without car crack and bubble; No rotten edges and uneven thickness;

4, the pattern should have no obvious deformation, no white eyes and white circle phenomenon;

5. The buttonhole should be smooth and smooth; The eye of the needle is not pierced and broken, and should be symmetrical and without large eye. If it is a dark eye button, the dark eye groove should be smooth and without obvious burst.

6. After electroplating or other processing, the effect should be uniform. If some special effects cannot be consistent, they can be packaged separately.

7, the same batch of buttons color difference should not be less than GB250 level 4 standard, compared with the sample, should not be less than GB250 level 3 standard.

8. Packaging inspection shall be carried out after the appearance inspection/performance test as required by customers is all qualified. A block certificate or other label should be placed in the package. The quantity of packages shall be in accordance with the regulations, and the actual quantity of each bag shall be in accordance with the regulations. If it is found that the thickness is different or other reasons exceed the allowance, the whole quantity shall be inspected.

9. The button/cover button/five claw button should be tested before delivery to test the performance and availability of the button, and provide the mold and test sample to the customer.


Two, the basic detection method of buttons

(1) Measurement of the basic dimensions of buttons

1. Use of cable cross section projector

The cable cross section projector projects the button on the projection screen according to the selected magnification (usually 10 times magnification), and calculates the aperture and hole distance of the open eye button through the micro drum wheel moving the button and the return trip of the screw. Compared with the reading microscope, using the cable projector to measure the aperture and distance of the bright eye link has the advantages of convenient operation, accurate measurement, and intuitive.

2. The application of geometric methods

The outer diameter of the round button is measured directly with a vernier caliper with an accuracy of 0.02mm. If it is a non-circular polyester button, draw the edge of the button on the square paper with a pen, find out its outer circle with plane geometry knowledge, and then measure the diameter of the outer circle with a vernier caliper with an accuracy of 0.02mm, accurate to 0.1mm. For non-round shell buttons or non-round copper buttons, draw the edge of the button on the square paper with a pen, find the large diagonal distance with geometric knowledge, and then measure it with a vernier caliper with an accuracy of 0.02mm, accurate to 0.1mm. In addition, it is difficult to obtain the outer diameter of non-circular buttons by intuitive methods. Rectangular coordinate system can be established in the square paper, and the diameter of the outer circle or the large diagonal distance can be calculated by the knowledge of analytic geometry.

(2) Test of eye hole tension

6 buttons were measured for the physical index of eye-hole tension specified in GB/T 28491-2012 "Natural shells" standard, and the final result was the lowest test result. However, QB/T 3637-1999 "Unsaturated Polyester resin Button" does not specify the number of eye hole tension measurement and the expression method of the final result. Due to the large individual differences in physical and mechanical properties of the same batch of buttons with the same specifications, the method of averaging a certain number of buttons cannot truly reflect the performance of the buttons, so it is preferable to measure the lower value of the specified number of buttons. Therefore, the eye hole tension of unsaturated polyester resin buttons can also be tested with 6 buttons according to the test method of natural shell button eye hole tension, and the low value of the test is taken as the final result.

(3) Test method for colour fastness of buttons

QB/T 3637-1999 "unsaturated polyester resin buttons" does not specify the number of buttons used in each color fastness, can refer to GB/T 29290-2012 "General technical requirements and testing methods for buttons unsaturated polyester resin class". 3 ~ 12 buttons are drawn from the sample as the sample (below 18L including 18L 12 buttons; 6 capsules above 18L and below 32L, including 32L; More than 32L including 32L take 3 capsules). The standard describes the color fastness to washing of shell buttons and copper buttons as "sewing the buttons on a 40mm×100mm multi-fiber interlining with white thread". During the test, it was found that if the buttons were only sewn on a 40mm×100mm multi-fiber interlining, the color of the interlining could not be accurately examined. The buttons are sewn between two multi-fiber interlinings so that the color of multi-fiber interlinings may be more scientific.

(4) Detection of heavy metals and decomposable aromatic amine dyes

Although there are provisions on the content of heavy metals and decomposed aromatic amine dyes in some current clothing standards in China, such as FZ/T 81014-2008 "Infant Clothing", GB/T 21295-2007 "Technical Requirements for Physical and Chemical Properties of Clothing" and other standards limit the content of about ten heavy metals. But the button standard does not stipulate the heavy metal content and the decomposable aromatic amine, nor does it introduce the test method of the extractable heavy metal content and the decomposable aromatic amine in the button. Therefore, the national standards for buttons need to limit the extractable heavy metal content and decomposable aromatic amines, and testing researchers also need to study the detection methods for the extractable heavy metal content and decomposable aromatic amines in buttons to improve the corresponding standards.


Three, button test test method detailed

Introduction to the British Standard button test method

Button test includes wear resistance measurement, button strength test, corrosion resistance of washing liquid, corrosion resistance of washing liquid, corrosion resistance of dry cleaning solvent, steam ironing resistance, ironing resistance, heat resistant head pressing performance, etc.

Step 1: Scope

This method is suitable for testing various buttons on clothing.

Note 1 The test cannot be used directly in actual laundry and dry cleaning because other factors, such as mechanical factors, cannot be repeated on a small scale, but it can be used to test the suitability of buttons for specific or general purposes.

Step 2 Sample

Batch sampling for each test shall be as follows (except for strength tests) :

5 samples were randomly selected from 1000 buttons

1001 to 10,000 buttons within 1000 to 2000 buttons, 5 samples were randomly selected, and each 1000 buttons were randomly increased by 1 sample

10,001-100,000 buttons

15 samples were randomly selected within 10,001-100,000 samples, and one sample was randomly added for every 10,000 additional samples

25 buttons are randomly selected from 100,001 buttons or above within 100,001 to 1000000 buttons, and 1 button is randomly added for each additional 100,001 buttons

In repeated tests, each test sample should be taken from the same batch as far as possible. The above steps are also required for strength determination (Article 4) except that 10 buttons are required for a small number of samples.

3. Wear resistance measurement

3.1 Overview This test is used to determine various types of buttons on common clothing.

3.2 Principle The button is mixed with a certain amount of pumice powder and placed in the cylinder to turn several turns per minute within a limited time. Then check the outside of the button for changes.

3.3 Instruments and Equipment

3.3.1PVC cylinder inner diameter 105mm, length 70mm, with cover. A 60r/min fractional horsepower motor is installed horizontally on the barrel.

3.3.2 Pumice powder dry, commercial grade, e.g., average diameter less than 425μm.

3.3.3 Balance measurement accuracy to 0.1g.

3.3.4 The diameter of fine screen is about 6.7mm.

3.3.5 Soft brush or whisk

Step 3.4 Weigh out 50g and put it into the cylinder together with the following samples:

(a)11-25mm buttons, 5;

(b)26-38mm buttons, 3.

Close the lid and rotate at 60 RPM for 30 minutes. Remove the lid, pour the pumice stone and button in the cylinder onto a fine sieve, sieve out the button, and brush the powder off the button with a soft brush. Repeat the same test procedure to test all button samples.

Carefully compare the sample to the untested button.

If no change in the appearance of the button can be seen under the light of the north sky, it is considered to have passed the test.

Note 1. In the Northern Hemisphere, button surface lighting uses northern day light (Southern day light in the Southern Hemisphere) or a similar light source with a brightness of 6001× or above. The light from the button about 45 degrees above the direction, along the vertical direction of the button to the horizontal direction of the eye.

Note 2. Change the pumice powder once for each batch of button samples.

3.5 Test report The test report shall include the following aspects:

(a) Test results, pass or fail;

(b) To give comments and suggestions on this standard;

(c) What deviations occur with this test method and the details thereof.

4. Strength test

4.1 Overview This test tests the bearing capacity of all types of buttons (diameter 10mm or above) against strong tension or impact during garment manufacturing or daily use.

4.2 Principle (a) When testing the hardness of the button, gradually increase the tension load on the button until the button surface cracks; (b) Release a certain mass of the pendulum from a certain height to test the hardness of the button.

4.3 Instruments and Equipment

4.3.1 Tension The chuck spacing of mechanical transmission tension meter is 6.35mm/min. Clamp around the button The 1.6mm welding rod can pass through the hole on the button and connect with the clamp. For other types of buttons * can use different connection methods for horizontal tension test. The clamp shall always hold the end of the electrode during the test.

4.3.2 Impact Collider. Button fixing clip suitable for fixing the button (see Figure 2)

4.4 Test sample 10 buttons are randomly selected for each test.

4.5 Steps

4.5.1 Tension

Thread the electrode through the buttonhole of the button under test (the four-hole button through the two diagonal buttonholes; The handle button goes through the handle). Mount the button and electrode on the tensiometer and gradually increase the pressure load on the button until the button or handle breaks, recording the Newtons of pressure. The same test method was applied to the remaining button samples.

Calculate the average pressure and record the large and small values.

Usually the large and small values do not exceed 25% of the mean. For example, if the mean is 100N, the error should not exceed a small value of 75N and a large value of 125N.

4.5.2 Impact force

Fasten the button to be tested on the right-sized clamp, facing the pendulum. A four-hole button leaks two holes, and a two-hole button reveals one hole. After fastening the button, close the clamp and install all components on the collision table with the attached screwdriver. Test buttons smaller than 15mm by lifting the pendulum to position 2, larger buttons need to go to position 1.

Release the handle, release the pendulum, and strike the button. Note if the buttons are broken, cracked, or deformed. Repeat the test until all button samples have been tested.

4.6 Passed or Failed conditions Buttons subjected to tension and/or impact force tests shall meet the following conditions:

(a) Tension test buttons shall be classified as "light" and "heavy" according to their tensile strength and diameter. Refer to Table 1;

(b) Buttons should not be broken, cracked or deformed during impact tests.

4.7 Test Report The test report should contain the following items

(a) Button strength (see 4.6)

(b) To give comments and suggestions on this standard;

(c) Detailed data on deviations with this test method.

5. Corrosion resistance of lotion

5.1 Overview This test tests the corrosion resistance of various types of buttons to laundry detergent in water at 40℃, 50℃, 60℃ or 95℃. These temperatures range from light to strong washes during the laundry process.

5.2 Principle The buttons and standard multi-fiber lined fabric together with laundry detergent or detergent are placed in the washing machine at a certain temperature for a certain time, rinsed and dried. Use the gray card to compare the color of the button with the fading of the fabric.

5.3 Instruments, equipment and reagents

5.3.1 Automatic drum washing machine, see Attachment A.

5.3.2 Beaker, or similar container, 750mL, capable of holding boiling water and containing all of the substance under test.

5.3.3 Method of heating beaker

5.3.4 Thermometer, ranging from 0℃ to 100℃.

5.3.5 Pockets for corrosion resistant steel balls. Square undyed cotton twill, approx. 100mm x 100mm, sewn together on four sides and fitted with 10 corrosion-resistant steel balls with a diameter of 6mm.

5.3.6 Grey card, refer to BS 1006, clause A02 and A03.

5.3.7 The width of the multi-fiber lining fabric is 100mm.

5.3.8 Soap solution: Each liter of deionized water contains 5g soap (refer to BS1006 clause C03) and 2g soda ash.

Note The soap quality can also refer to the British standard BS1912.


Detergent, per liter of deionized water contains 4g detergent (refer to BS1006 clause C06) and 1g soda ash.

5.4 Composite Sample

Buttons to be tested (not more than 5) are sewn equidistant at the center of the fabric,

A second piece of fabric covered it and was sewn with thread around and between the buttons. Prepare the remaining buttons in the same way.

Note 1 Large buttons may need to prepare more combined samples. Each combined sample shall be tested separately.

5.5 Test each combination sample in sequence of steps as follows:

Heat enough soap solution (5.3.8) or laundry solution (5.3.9) in a beaker to 40 ° C, 50 ° C, 60 ° C or 95 ° C or other required temperature.

Place the composite sample and two bags of steel balls together. Heat the liquid in the beaker to the test temperature of +2 ° C within two minutes and pour into the washing machine. When the temperature drops to the test temperature, close the washer cover and run at 35±2 RPM for 30 minutes.

Pick out the composite sample from the solution, wash it with water and hang it to dry. Cleaning and drying should be done at room temperature (about 20℃).

Separate the two pieces of fabric and examine them separately. Allow a dry cloth to wipe any sediment that may remain on the button surface.

Use a gray card to compare button color changes with the fading of the fabric.

Check the buttons for damage, such as softening, swelling, bubbling, cracking, breakage or discoloration.

5.6 Pass or fail conditions shall be deemed to have passed the test if the following conditions are met:

(a) The color fastness of buttons should not be less than 4 when detecting color changes with gray cards.

(b) The stain of the fabric should not be less than 5 when the gray card is used to detect the fading of the fabric.

(c) No deformation or other defects.

5.7 Test Report The test report shall contain the following items:

(a) Test results, pass or fail