LyondellBasell Technical Tip

tech.topic

Adhering Labels and Inks to

Most milk, water and juice If all-around treatment of containers is containers are decorated with plastic or required, each can be dropped labels, screen-, etc. Since the useful through a ring-shaped burner or rotated as it life of the container is only seven-to-ten days, passes through a wall of flame. the label or the ink need not adhere longer than that time. However, it is still important to EFFECTIVENESS OF TREATMENT have good adhesion during the of the Determining effectiveness of treatment is . especially simple for in-plant molding operations where the containers go directly One of the biggest drawbacks of polyethylene from molding to treatment to decoration.

containers is their poor adhesion to printing Follow various steps mentioned below.

inks and glues in labels. Poor adhesion is due

1. Pick a newly decorated container off the to chemical incompatibility and the inability of line and determine whether a paper label the ink or glue to “wet-out” the surface of the container, can be peeled off. For ink, press a strip of cellophane tape onto an inked area and FLAME TREATMENT see whether the ink comes away with the To remedy the lack of wetting-out, the area tape. If treatment is found to be that is to receive the ink or adhesion label incomplete, either the flame is not rich needs to be treated. The most common enough in oxygen or the treatment time is method is flame treatment. Other methods are too short. discussed later. 2. To correct, first increase the air-to-gas In flame treatment, it is important that a gas-air ratio. If this fails, check the treatment time. mixture rich in oxygen feed the flame. The usual ratio of air to gas is 10:1. Flame 3. The line speed may have increased by treatment results in the oxidation of a very thin improved molding and filling operations. In layer of the container's surface. The net result this , the treatment time may

is enhanced chemical compatibility with inks automatically have been reduced. Bring it

and glues and better wetting of the back to normal by increasing the length of

the flame path through the use of a wider polyethylene surface. burner or the addition of a second burner.

The container is in contact with the flame only a few tenths of a second. This is usually If containers are blow molded, treated and sufficient to produce the desired results. Also, then stored for hours or days before use, or if the short time of contact does not slow down they are molded and treated at one location, either container production or the filling then shipped in bulk to the dairy, then testing operation. More importantly, the short time containers on the decorating-filling line is does not allow excessive heat to build up and inadequate. Too many defective containers distort the container. If treatment is desired can be produced before a test reveals poor only on one face of the container and that face treatment. needs to be oriented on a conveyor system, a vertical strip burner may be employed.

(Continued on Page 2)

Page 1 of 2

LyondellBasell Technical Tip

tech.topic

Adhering Labels and Inks to Plastic Containers (Continued)

1. In these situations, use a carbol fuchsin clean. Exposure to a dirty, smoky atmosphere test. This material is a dye that can be will render the treatment ineffective. Moreover, obtained in solution form from most it is unsanitary.

chemical or scientific supply houses. The OTHER METHODS OF SURFACE treated portion of a container is painted TREATMENT with the solution and rinsed with water. While flame treatment is the easiest, most The more highly colored the part, the economical and fastest method of surface better the treatment. When you determine treatment, other methods are available, but the degree of the color you need for good have limited application for liquid food . ink or glue adhesion, keep a dipped container to use as a standard and A high-voltage, corona discharge, a popular compare test containers with it. If the color treatment in film sheeting operations, has is at least as intense as the standard, the found use in some high volume blow-molding level of treatment is sufficient. lines. This method consists of passing the containers through a corona field that is 2. A simpler, although somewhat less confined to a chamber. It is important to reliable, test can be performed by dipping properly vent the ozone that is generated in a treated container in clean room this process. This method is advantageous in temperature water. Remove the container its ability to treat irregular shapes. and note how long a continuous film of water remains on the surface before Yet another method calls for the immersion of breaking up into droplets. Generally, a film the container in a bath of chromic acid to retention time of more than five seconds oxidize the surface. The bottle is then indicates good treatment. thoroughly rinsed with water, dried and conveyed to the printing or labeling station. It is strongly recommended that treating occur This achieves the same results as flame just prior to affixing labels or printing. However, treatment, but this chemical is toxic and this if there is a time lag between treating and treatment is not recommended. decorating, keep the containers For more information about , contact your LyondellBasell sales or technical service representative.

Before using a product sold by a company of the LyondellBasell family of companies, users should make their own independent determination that the product is suitable for the intended use and can be used safely and legally. SELLER MAKES NO WARRANTY; EXPRESS OR IMPLIED (INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR ANY WARRANTY) OTHER THAN AS SEPARATELY AGREED TO BY THE PARTIES IN A CONTRACT.

LyondellBasell prohibits or restricts the use of its products in certain applications. For further information on restrictions or prohibitions of use, please contact a LyondellBasell representative. Users should review the applicable Safety Data Sheet before handling the product. LyondellBasell Industries Adflex, Adstif, Adsyl, Akoafloor, Akoalit, Alathon, Alkylate, Amazing Chemistry, Aquamarine, Aquathene, Arcopure, Arctic Plus, Arctic Shield, Avant, Catalloy, P.O. 3646 Clyrell, CRP, Crystex, Dexflex, Duopac, Duoprime, Explore & Experiment, Filmex, Flexathene, Glacido, Hifax, Hiflex, Histif, Hostacom, Hostalen, Ideal, Integrate, Houston, TX 77252-3646 Koattro, LIPP, Lucalen, Luflexen, Lupolen, Lupolex, Luposim, Lupostress, Lupotech, Metocene, Microthene, Moplen, MPDIOL, Nerolex, Nexprene, Petrothene, Plexar, Polymeg, Pristene, Prodflex, Pro-Fax, Punctilious, Purell, SAA100, SAA101, Sequel, Softell, Spherilene, Spheripol, Spherizone, Starflex, Stretchene, United States Superflex, TBAc , Tebol, T-Hydro, Toppyl, Trans4m, Tufflo, Ultrathene, Vacido and Valtec are trademarks owned or used by the LyondellBasell family of companies. www.LYB.com Adsyl, Akoafloor, Akoalit, Alathon, Aquamarine, Arcopure, Arctic Plus, Arctic Shield, Avant, CRP, Crystex, Dexflex, Duopac, Duoprime, Explore & Experiment, Filmex, Flexathene, Hifax, Hostacom, Hostalen, Ideal, Integrate, Koattro, Lucalen, Lupolen, Metocene, Microthene, Moplen, MPDIOL, Nexprene, Petrothene, Plexar, Polymeg, Pristene, Pro-Fax, Punctilious, Purell, Sequel, Softell, Spheripol, Spherizone, Starflex, Tebol, T-Hydro, Toppyl, Tufflo and Ultrathene are registered in the U.S. Patent and Trademark Office.

6892R/0715 Page 2 of 2