Composite bags is faulty, affect product how to do?
Bags have peculiar smell not only affect the packing contents, will harm the customer's health to some extent, is a product safety problem that nots allow to ignore.
How to cut the peculiar smell of the composite bags has become the basic requirement of the packaging industry.
Here, professional manufacturer of flexible packaging is combined with its own rich experience in composite bags produced to interpret the bags to produce peculiar smell the cause and the solution.
A, film odor source of the odor comes mainly from two parts: the resin itself all kinds of increasing agent and its low molecular substances;
Flexible packaging in the processing of peculiar smell.
Film, all kinds of printing ink, adhesives, organic solvent will bring all sorts of peculiar smell.
Packaging materials produced by the peculiar smell, phyletic and various, complicated and has a sweet taste, stink, sulphur, ingredients, coke smell, stone LaWei, oil, printing ink, soap, oil, solvents, etc.
Peculiar smell not only caused by a substance, is often caused by a mixture of several substances, even describe the peculiar smell is particularly difficult, because of the mixture composed of small changes will lead to the difference of odour.
1 second, the source analysis, the influence of the resin itself film is usually made by a polymer resin, resin is molecules by different sizes, and different molecular weight distribution of the resin, the content of low molecular is different also.
Low molecular substances in extrusion process is easy to oxide volatilization, smell.
Resin synthesis process solution method and meteorology act, composed of two different law itself also have differences in odor: solution method due to the process after the composition by removing solution, many low molecular substances is to eliminate, so taste is better than meteorology act in theory.
To increase many enhancers to improve the performance of the resin, the increase is the biggest source of flavor.
Smooth agent is generally amido compounds, some sweet taste.
The flavor of the antistatic agent is very blunt nose, may not be used in low odor packaging.
Opening agent general is given priority to with inorganic substances, usually of calcium carbonate and silica.
But in terms of opening effect, and silicon dioxide is far better than that of calcium carbonate, but it is better in terms of taste of calcium carbonate in silica.
Antioxidants are usually phenol kind thing, have some flavor.
General linear molecule with catalyst residue problem, thus it is necessary to add antioxidants.
Commonly used white color masterbatch, masterbatch usually add some wax and stearate as dispersant and lubricant.
These low molecular substances in the processing time, taste is very big, therefore in the multi-layer co-extrusion as far as possible in the middle.
2, composite bags appeared in the process of producing odor of 1.
Thermal decomposition to produce polyethylene decomposition odor material composition, can be roughly divided into aliphatic hydrocarbons and aromatic hydrocarbons two kinds big.
According to the study of thermal decomposition for three carbon to 28 carbon saturated or unsaturated hydrocarbons, which short branched chain of three to six carbon carbon compounds, the biggest influence on contents, due to the low volatility, polarity is not high, these substances in the membrane can be preserved for a long time.
Thermal oxidation to produce peculiar smell plastic machining under the high temperature and high shear force, in addition to the thermal decomposition, after extrusion mold opening, also in the thermal oxidation reaction with the oxygen in the air, the material can also cause bad breath.
Produce peculiar smell surface corona treatment in order to make the ink and glue or agent has good viscosity, different plastic film corona or flame treatment is necessary.
Because of oxidation reaction makes stronger the surface tension of the offset, in the subsequent use of coating will be encountered in the process to produce a set of material,
Alcohol, aldehyde, ketone and carboxyl)
Assume that handle strength increased, not only can make the surface tension increases, and increased the degree of polymer degradation, and then produce yi transpiration of small molecules (
Aldehydes and ketones)
These easy transpiration of aldehydes and ketones can produce peculiar smell.
Heat sealing in the high temperature thermal bonding, produce peculiar smell in the composite film materials will increase thermal differentiation agent to separate, ink, adhesive transpiration differentiation of the various components will produce peculiar smell.
Plastic enhancer of peculiar smell in the process of processing molding, plastic to trek the function of the machinability or improved products, will add various additives, variety omissions, the different components, is one of the primary elements constitute a peculiar smell.
Such as plasticizer, heat stabilizer, antioxidant, anti-uv agents, lubricants, opening agent, antistatic agent, antifoggant, etc.
Other also increase may increase the risk of functional inorganic materials, such as calcium carbonate, kaolin, talc, silica, etc. , and will bring in a lot of dispersing agent, coupling agent, etc. ;
Again is to increase the kinds of organic pigment masterbatch, titanium white mother, etc. , will produce many transpiration substances when heated, assume that the increasing number of pigment can promote the polymer such as differentiation, will produce serious odor when heat sealing.
Printing ink, adhesive residue solvent ink, glue residue solvent of odor in the midst of composite flexible packaging materials, the main elements of bad smells from the printing ink, adhesive solvent residual, especially in dry compound, solvent residue cannot be completely avoided, now international residue solvent 5 mg / ㎡, benzene class may not be checked out.