Because I cannot fully understand your question literally, I will answer it in the following way:
1. If the signboard you are talking about is a brand, then, if you want to make your own brand To increase the intangible assets of patent rights, you need to tap into the potential technical resources your company has, organize them into technical solutions, and then apply for a patent. Once authorized, it becomes a patent right.
2. If the signboard you are talking about is an object, such as a sign made of wooden boards, then it depends on whether your wooden board production is related to a specific new technology. If so, you can consider applying. patent.
Note: 1) The above answers are hypothetical answers. There may be some inappropriateness.
2) When applying for a patent, the core point is that you must have technical resources, such as technical personnel, or innovative products related to technology.