|Physical state||Soluble in water||Other solubilities|
|KETJENFLEX® 2||Solid||No||Acetates, ketones, alcohols|
|KETJENFLEX® 4||Liquid||No||Acetates, ketones, alcohols|
|KETJENFLEX® 6||Solid||No||Acetates, ketones, alcohols|
|KETJENFLEX® 8||Liquid||No||Acetates, ketones, alcohols|
|KETJENFLEX® 9S||Solid||No||Acetates, ketones, alcohols|
|KETJENFLEX® 12||Liquid||No||Acetates, ketones, alcohols, hydrocarbons|
Can I use KETJENFLEX® 8 to improve adhesion and lamination bond strength in lamination inks with BOPP protective film?
KETJENFLEX® 8 has recently been tested for BOPP in lamination inks with similar results as with PET protective films to which KETJENFLEX® 8 shows excellent adhesion promotion. The lamination bond in this case was BOPP (inner) to BOPP (outer film). It should be added the BOPP films must be corona or flame treated in order to get any ink to stick.
No, the KETJENFLEX® range without exception contains phthalate free products. The basis is either sulfonamide or biobased citrate esters.
KETJENFLEX® 8 can be combined with all common organic and inorganic pigments. A significant amount of packaging materials offered in stores contain inks based on nitrocellulose, KETJENFLEX® 8 and various pigments, which perhaps is the best evidence of success.
KETJENFLEX® 8 is insoluble in water but still can be used in water borne systems. The stability depends on the compatibility of the resin with KETJENFLEX® 8. Being rather polar KETJENFLEX® 8 best matches with polar resins, such as Polyvinyl Acetates (PVAC), Polyurethanes (PUD), Acrylates and Polyamides (used as hardener for WB epoxy).
Formulating KETJENFLEX® 8 in such a waterborne system may require some time and vigorous mixing.
KETJENFLEX® 12 is insoluble in water but still can be used in water borne systems. The stability depends on the compatibility of the resin with KETJENFLEX® 8. Being rather polar KETJENFLEX® 12 best matches with polar resins, such as Polyvinyl Acetates (PVAC), Polyurethanes (PUD) and Acrylates. Formulating KETJENFLEX® 12 in such a waterborne system may require some time and vigorous mixing.
The sulfonamides solve in most organic solvents except hydrocarbons. KETJENFLEX® 12 is compatible with all commonly used SB systems.
What is the mechanism behind the tensile strength improvement of nitrocellulose and polyurethane formulations with KETJENFLEX® 8?
Rigid, hard resins tend to have strong internal bonds mostly buildup of hydrogen bridges, which prevent substrate adherence. Due to the excellent compatibility of KETJENFLEX® 8 with polar resins such as nitrocellulose and polyurethane the hydrogen brigdes are effectively broken. The result is that the resin becomes softer and adheres better to the substrate. Better substrate adherence is reflected in higher tensile or tear strengths.
KETJENFLEX® 8 and 12 are compatible with most formulations ingredients and may be combined with any other plasticizer suitable for the same application.
Normally 3-4% of KETJENFLEX® 8 or KETJENFLEX® 12 in the total formulation should be enough to bring plasticization and adhesion promotion to the final system.
KETJENFLEX® 8 and KETJENFLEX® 12 are monomeric plasticizers with a molecular weight of 199 and 402 respectively. Although not small the molecules do not respect the non-migratory weight of 1000 Dalton. The migration strongly depends on the formulation composition and the films used. It is worthwhile mentioning both KETJENFLEX® 8 and 12 are FDA approved and feature on the Swiss list.
In order to estimate the compatibility it is best to look at the resins and KETJENFLEX® polarity and the corresponding solubility parameters. We have tables to check this. In general KETJENFLEX® 8 is compatible to more polar resins like PA, NC, PU, PVAC and PVB. KETJENFLEX® 12 is a bit more mid-range and is compatible with NC, PVAC, Acrylics, Vinyl resins and PVC
KETJENFLEX® 8 is known to retain the solvents a bit and thus may slow down the evaporation. In practice however we have never experienced delayed or slow processes of formulations with KETJENFLEX® 8 nor with KETJENFLEX® 12. Linespeeds of 600-800m/minutes have been reported with NC/PU system containing KETJENFLEX® 8 or KETJENFLEX® 12.
This we have not tested yet. A definitely use of KETJENFLEX® 8 and 12 is in adhesive lamination where both substances increase the bond strength of the laminate.
Yes both KETJENFLEX® 8 and KETJENFLEX® 12 can definitely be used in adhesive lamination increase the bond strength of the laminate.
In principal KETJENFLEX® 8 and 12 as such do not influence the COF as they are not surface active. Though since plasticizers are used to soften the film, COF may be affected and most likely will increase a bit. It is good to bring a nuance, in the case of packaging in which the lamination process is used the ink is between to plastic films and COF is less and issue.