No, quarks do not gain or lose color charge when interacting with each other. The concept of color charge in quantum chromodynamics (QCD) is analogous to electric charge in quantum electrodynamics (QED), but there are some important differences.
In QCD, quarks carry a color charge, which comes in three types: red, green, and blue. Antiquarks carry anticolor charge (antired, antigreen, and antiblue). Gluons, on the other hand, are the carriers of the strong force and can interact with quarks and other gluons.
When quarks interact through the exchange of gluons, the gluons can change the color charge of the participating quarks. However, the overall color charge of the system remains conserved. In other words, the total color charge before and after the interaction remains the same.
The exchange of gluons between quarks is what allows the strong force to bind quarks together inside hadrons (such as protons and neutrons) and create composite particles. This phenomenon is known as color confinement, where individual quarks are not observed in isolation due to the strong force.
To summarize, while gluons can mediate the transfer of color charge between quarks during interactions, the quarks themselves do not lose or gain color charge in the process. The total color charge of the system remains unchanged.