It can be purchased, you need to contact the patentee.
Take invention as an example to briefly explain the patent protection model:
A certain person invented a new machine and applied for a patent to the patent office. During the application process He must disclose without reservation the technical features of the invention, including details.
Therefore: the technical features of a patented invention are fully disclosed, but others may not use it without the permission of the patentee. The same applies to other patents (utility models, designs).
If you want to use this patent, you cannot use it arbitrarily just because its technical features are public. You must contact the rights holder and obtain their authorization before you can use it.
The specific ways to purchase the right to use a patent are generally as follows
1. Buy out, buy the patent right completely, and others (including the original patentee) will be able to use it in the future If you need to use this patent, you must obtain your authorization, which costs a lot.
2. Purchase the exclusive right to use the patent for a period of time, that is, only you can use the patent within the time range agreed between you and the patent owner.
3. Non-exclusive right to use, that is, you obtain the right to use the patent through purchase, and others can also purchase the right to use the patent from the patentee.