Tackiness / Tacky
Tackiness is the characteristic of “stickiness” of a rubber. Most Chinese rubbers have some level of tackiness where you can lift up a ball by simply pressing the rubber on top of the ball, and raising it up. Non-tacky rubbers don’t have this stickiness and will never pick up a ball, but they still have grip, so they can still generate a lot of spin on your shots, but not as much as tacky rubbers. Most Japanese and European rubbers are grippy but not tacky.
Tacky vs non-tacky rubber
Reddit Discussion
As I understand it, tacky and non-tacky rubbers generate the bulk of their spin differently.
Since non-tacky rubbers rely on the ball sinking in to the sponge to generate spin, this helps explain why short game is generally more difficult to control with rubbers like T05. Tacky rubbers don’t suffer from this same issue because the spin comes more from topsheet contact and gripping of the ball, which applies at both low and high racket speeds.
Furthermore, since tacky rubbers are often paired with harder sponges, the rebounding effect of the ball is lessened since it doesn’t come out of the sponge with much speed. This further improves the control of the rubber in short game or control type situations.
Also, OP’s point about spin generation at low speeds is another good one to note. Tacky rubbers can generate high amounts of spin on low speed shots like serves because of how they generate their spin. That’s not to say that non-tacky rubber types cannot generate as much as spin as tacky rubbers, but the control required to do so is higher and the brush must be very fine; otherwise, the length of the service tends to drift long.
Looking at rubbers broadly, you’re on the right track. Tacky rubbers are considered to be better at making spin and control over/around the table. Grippy rubbers are considered to better at making power and in the rally.
Tacky top-sheets are typically paired with harder, dense sponges. The combination makes for a slower rubber with linear play characteristics - power in = power out. This is great for making spiny topspin shots, drop-shots, and flicks, shots that benefit from control and nuance. This not as great for making powerful shots. The tackiness and hard-sponge require more power to make a more powerful shot, so the player needs strength and good technique to support that.
While it’s true that tacky rubbers produce most of their spin on contact and non tacky rubbers produce most of their spin on rebound, that’s not to say that tacky rubbers don’t produce any spin with the sponge.
By maintaining some brush in the contact alongside more direct ball impact, you can also engage the harder sponge that is often paired with tacky rubbers to combine the spin from the topsheet along with the spin from the sponge.
When we are talking about high speed balls, we know that the incoming ball already has a lot of energy - this is why the speed of the ball is high. If you think of spin generation as applying energy to the ball in a tangential manner, then you also realize that you can “borrow” the the energy of the incoming ball to both engage the sponge and topsheet of the tacky rubbers to still produce a shot with high spin. In fact, I believe that the range for much spin you can generate with a tacky rubber is larger than the range of spin you can generate with a non-tacky rubber.
YouTube Resources
Ping Sunday Channel EmRatThich - Chinese rubber (DHS Hurricane) vs High Tension rubber (Tenergy)