Common problems of film manufacturers: adhesion between plastic films; The smoothness of migration masterbatch affects the thermal sealing printing performance of the film. The main reason is that after the film is closed, the films form a vacuum compact state, which is not easy to separate. The solution is to add slip and anti-blocking masterbatch;
For films with heat sealing and printing requirements, non-migrating, low friction resistance masterbatch can be selected.
1. This paper will be introduced from the following three aspects:
Through three aspects elaborate on the choice of slip and anti-blocking masterbatch, so that you are reading this article and have a deep understanding.
(1) Selection of slip and anti-blocking masterbatch that can meet the performance requirements of the film
(2)The choice of slip and anti-blocking masterbatch for the opening of common packaging film products
(3)Common problems and solutions for the application of slip and anti-blocking masterbatch by film manufacturers
2. The role of slip and anti-blocking masterbatch
The slip and anti-blocking masterbatch is composed of carrier resin, an anti-blocking agent or smoothing agent, and various additives. The slip and anti-blocking masterbatch mainly include:
a.Oleic acid amide
This is characterized by a small molecular structure, precipitation fast, good lubricity, and cheap price, some domestic only 10 Rmb/kg, but oleic acid amide is very easy to yellow, not high temperature resistance, but also easy to precipitate the surface of the film, short aging, seriously affect the quality of the product, at the same time precipitating too much will affect printing and heat sealing, this is a lot of low-quality smooth master raw material choice;
b. Erucerate amide
It is more than oleic acid amide in carbon number, large molecular weight, is relatively stable, good lubrication effect, is not easy to yellowing, has high-temperature resistance, long aging, and long-term will occur in the part of yellowing, but the price is expensive; And Genuine Plastic’s new materials used imported erucic acid, and successfully produced high purity open masterbatch, not only can make the opening smooth a function is stable, but also can help customers reduce the final cost;
c.Micron SiO2
The choice of SiO2 is very important, must choose add a small amount of anti-stick effect is good, and the particle size is suitable, the refraction coefficient and film resin close, based on the above, but also take into account the SiO2 must be easy to disperse, dispersed SiO2 will affect the film’s apparent and optical performance and printing performance.
When we are familiar with the types of smoothing agents and the function of the smoothing masterbatch, the most important question for the film manufacturer is: how to choose the right smoothing masterbatch?
3.Choose the general principle of slip and anti-blocking masterbatch
In addition to the selection of slip and anti-blocking masterbatch considering its excellent opening anti-blocking effect, there are mainly the following points:
a. Optical properties:
To obtain the best transparency and the lowest degree of fog, the opening smoother must be selected with a refractive index similar to the resin (1.49), narrow particle size distribution, suitable particle size, and less addition can achieve the required opening effect.
b. Dispersion:
The size of the anti-adhesion agent is very important, the The smaller the particle size, the worse the dispersion, and the larger the particle the size will affect the apparent property and optical properties of the film, the size of the anti-blocking masterbatch is generally 2-10 microns, which requires the masterbatch manufacturer to have high dispersion twin-screw unit and rich masterbatch dispersion production experience.
c. Heat sealing and printing performance:
Generally, corona or flame treatment is required to increase the surface tension and surface energy of the film before heat sealing and printing. However, an inappropriate slip masterbatch will migrate to the surface of the film and affect the thermal sealing and printing performance of the film, resulting in low peeling strength and weak ink adhesion between the films. Film manufacturers with strict requirements on this aspect can choose a low friction coefficient. Non-migrating slip and anti-blocking masterbatch.
d. Metallized film scratch resistance performance:
To prevent the inorganic anti-blocking masterbatch from penetrating the film and weakening the water vapor and oxygen barrier performance, the shape of the anti-blocking masterbatch can be selected as round and soft particles, which can ensure the film has better barrier performance.
e. Anti-wear performance of the machine:
Some inorganic anti-blocking hardness is large, and the machine wear is very large, this is also the film manufacturer should pay attention to.
f. Filter blocking problem:
If the film manufacturer encounters a high rise in the filter pressure difference or a sudden rise in the pressure difference, it may be necessary to consider replacing the slip and anti-blocking masterbatch.
g. Price:
Cost is also the key factor to consider after meeting the above basic performance.
4.The selection of slip and anti-blocking masterbatch of common film
(1) Aluminium plated film
A lot of food packaging is aluminized film, which has excellent the oxygen barrier and prevent oxidation, and aroma loss performance also has anti-UV, prevent the loss of vitamin performance, under very high vacuum conditions, aluminum at the temperature of 1500 degrees will vaporize, and then in the film has been treated on the surface of an extremely thin layer of the aluminum film, to ensure the adhesion of metal and film, The film must have a high wetting tension.
The selection of slip and anti-blocking masterbatch of the aluminized film opening requires:
a. Masterbatch carrier should be selected with high wetting tension as far as possible;
b.The movable opening slip and anti-blocking masterbatch must be disabled;
c. The anti-block and slip effect of the film must be achieved by adding anti-blocking masterbatch;
d. The size of the anti-blocking particle depends on the the thickness of the film surface;
e. The shape of the anti-blocking masterbatch must be round and soft, so as not to Pierce the aluminum plating layer
(2) Cigarette packaging film
Smoke film material is BOPP bidirectional stretching polypropylene, which is made of a variety of polypropylene functional materials for co-extrusion, bidirectional stretching molding.
The friction coefficient is an index to measure the sliding characteristics of BOPP cigarette film. The friction coefficient of the two sides of the film must be different, and the differential sliding characteristics of the inside and outside of the film must be formed. The friction coefficient close to the side and inside of the cigarette packet paper should be controlled to be high, while the outside of the film should be controlled to be very low.
The selection requirements of slip and anti-blocking masterbatch: