In the 1960’s, the next major breakthrough occurred with the development of metal or zinc cross-linked (metal interlocking) acrylic polymer finishes.  When electrically charged ions of zinc and zirconium are added to a polymer, they cause a chemical process called cross linking or interlocking that makes the plastic particles stick to each other and to the floor surface resulting in a very durable floor.  Unfortunately, these products would prove to have a detrimental impact on the environment.  The resulting metal-link polymer floor finishes have several advantages over other polymer finishes:

• You can scrub floor surfaces with a mildly alkaline cleaner without damaging the finish.

• You can strip the floors easily and quickly with a high-alkaline or caustic stripper (pH of 10-12).

• You can apply coats of finish on top of old coats of interlocked finish and they will stick to the floor surface very well.  

• By mixing various synthetic substances together, manufacturers can create a finish for almost any floor surface need.

• These products are extremely detergent-resistant and can be scrubbed with normal cleaners without having to worry about removal. 

They were hard and brittle and tended to powder when burnished with the new high speed equipment introduced in the 1970’s.  Before the introduction of high speed equipment, floor machine buffing was done at 175 rpm.  Then came 350-500 rpm’s.  Now machines are available with 1000, 1200, 1500, 2000 and 2500 rpm’s.  Due to the heat and abrasion generated by these high speed machines, the older, metal cross link finishes would tend to fracture, shatter, and powder off the floor.

As a result of high speed machines, polythermic floor finishes were introduced to withstand the heat and abrasion generated.  The high speed burnishers abrade the floor finish and smooth it into a “wet look” during the curing process.  Polythermic finishes rely on a new generation of polymers that don’t powder because they form a film on the floor surface that has a high degree of flexibility.  Originally, manufacturers were trying to develop finishes that were harder, so that they would stand up to the heat and friction of the higher speeds, but they found that the real key was flexibility.

A modern high speed floor finish is composed of three major ingredients and a number of less significant, although still important additives.  The three major ingredients are polymer, synthetic “wax,” and solvents.  

Your comments and questions are always welcome.  I hope to hear from you soon.  Until then, keep it clean…


Mickey Crowe has been involved in the industry for over 35 years. He is a trainer, speaker and consultant. You can reach Mickey at 678.314.2171 or