The main reason for the food packing bag smell

food sack the causes of odor basically has the following two conditions:

a, the smell of printing paper itself exists.

2, printing ink, Including light oil) Residual smell, can be divided into the smell of solvent residual and residual ink after curing resin monomers or polymers. Aiming at the complicated and changeable situation, can consider to be from the following three aspects: to improve the printing ink quality and print quality and control.

food packaging bags have peculiar smell is inevitable, but does not have a harm to human body, you can be at ease use. For food packaging testing content is as follows:

a detection, heavy metal content

the current testing standards for heavy metals are food packaging regulations on hygienic standards GBll680-89 base paper of arsenic, lead, the ec of toys EN71-3 * standard eight elements. Heavy metal content of sample preparation first let the client to natural drying at room temperature, the ink again after with aperture of 0. 5 mm metal mesh filter, get at least 100 mg of solid powder; Then the hydrochloric acid solution with 50 times ( C = 0。 07年mol / L, 37 ± 2℃） Mix powder in the container, oscillation after 1 min, testing the pH value, control of pH value in 1. 0 to 1. 5; The mixture in the dark and 37 & plusmn; 2 conditions, sustained oscillation 1 h, then let stand for 1 h after separation and filtering out the solid from the solution as soon as possible, if necessary, you can use the centrifuge, the centrifugal separation time can't more than 10 min. * after to get the solution of samples by inductively coupled plasma mass spectrometer for testing, the testing data after conversion processing, get the heavy metal content of data, the results by mg/kg. Paper and cardboard in the testing process and the process is basically the same. At least 100 mg, first of all, the paper tested the sample in 37 & plusmn; 2 ℃ temperature, soaking with 25 times the quality of deionized water, make its become soft homogenization; Then quantitative transfer into the container, add 25 times the quality of hydrochloric acid solution ( 0. 14 mol / 1 (soil 2 ℃) , oscillation after 1 minute, testing the PH value, control of PH value in 1. 0 - 1. 5. The following process with the ink processing.

2, VOC content detection standard

now to test the VOC content of the standard can consult our country industry standard composite plastic film gravure ink, QB / T2024 - 1994). 5. Article 8, the headspace gas chromatography. Measuring device using FID type gas chromatograph, the cigarette case print cut into 200 cm2 put people in 500 ml flask, with silicone rubber plug seal, after 50 & plusmn; 1 ℃ constant temperature heat preservation in the 30 min, with 1 ml syringe pump gas into the gas chromatograph in the flask test, get a sample of each corresponding solvent peak area. Solvent adopted by various standard curve to calculate the amount of residual solvents in the print, the result by mg/m2, this standard specifies the solvent residual * high limited to 30 mg/m2.

and control methods for determination of the three, the mei

with the smell of cigarettes packaging also not quantitative measurement, only scientific statistics are used to indicate average people's subjective feeling, so generally can be divided into five levels, see table 2 category description. The peculiar smell of the cigarette packaging should be at or above level 2 standard. Despite the general smoke target solvent residues test results meet the related standard, but smell smoke target is objective existence, sometimes reached level 3. This suggests that the odor or not be detected; Or existing standards too wide, within the scope of qualified have smell; Or print the drying condition change effect of the factors such as the size of the peculiar smell.