The Arizona Fall League is often a testing ground for new ideas that MLB hopes to eventually implement in the majors; the 2016 AFL season saw the use of a chemically treated ball, having a tackier feel. By February 2017, it was again reported that MLB is developing a chemically treated baseball, suitable for use in major league games. As Paul Hagen reports, “The purpose is to eliminate the need to rub down the balls before each game with a special mud that takes the gloss off the surface and makes it easier to grip.”
That “special mud” is supposed to impart a tackier feel, and every ball is treated with it. But of course, people are always looking for a potential competitive advantage, however slight. So using foreign substances on baseballs to improve one’s grip on the ball is nothing new. People use various combinations of rosin, pine tar, and sunscreen to achieve a tackier ball so that they can get a better grip. And technically, it’s against the rules.
It’s not clear if the spring 2017 report refers to the baseballs used in the AFL, or if they’ve revamped the balls since AFL. But I suspect that Rawlings is applying football technology to baseballs. Grip Boost is a company started by a University of Maryland graduate which makes “a product tacky enough to help receivers snag balls, but not so sticky it violates football rules“. It dries instantly, although they don’t specify whether it is a rub-on product or a spray. If that wasn’t obvious enough, they explicitly state, “The company recently introduced a version formulated especially to replace messy pine tar in baseball”.
This article from U of Maryland provides a little more technical detail. The science behind Grip Boost’s product(s) is based upon “strategically modified chitosan, a natural biopolymer with high adhesive and tack properties”. As the article reports,
[the researchers] took up the challenge of creating a chitosan-based, NCAA-compliant product that did not leave residue on the ball, did not exceed the tackiness of existing gloves, and could be used quickly and easily. The team verified Grip Boost met the first two requirements using friction coefficient, tack and residue tests, and addressed the third by making the modified chitosan highly soluble in alcohol.
The result was a quick-drying, easy to use, clear gel. Players apply a small amount to their gloved hands and rub them together. When the alcohol evaporates 15–20 seconds later, a thin, tacky film is left behind, restoring the gloves to their original condition. A two-ounce bottle of Grip Boost contains about 60 applications.
Finally, it appears that published patent application US 2015/0147468 is the actual product:
A formulation for coating surfaces, for example gloves, with a tacky film comprises a hydrophobically modified biopolymer, where the hydrophobic modifications of the biopolymer correspond to between 1 and 90% of available functional groups, a plasticizer, and a volatile solvent. The formulation quickly dries into a tacky film that provides an enhanced friction of the surface.
I can’t speak to the motivation behind this – even though the special mud comes from a very particular source, I doubt it is expensive. Perhaps they’re just looking for consistency? Although the reports claim that the chemically treated baseballs will reduce cheating, I don’t think a MLB-approved, tackier ball is going to stop anyone from using foreign substances if they perceive said substances will provide an added advantage.