What's the best way to send emails to collectors?

I would like to send an email to everyone who has purchased one of my paintings - my “collectors”. I have collected their email addresses through the purchasing process. I’ve been reading MailChimp’s guidelines for list compliance and I’m not sure this way of collecting emails complies with their guidelines. How are other artists staying in touch with their collectors? I want the process to be as easy and efficient as possible.
Thanks,
Marilyn Place

I have never mass emailed collectors outside my area, but if I were going to, I would consolidate addresses in a mail group and send a personal email. Mail Chimp is cool, but aside from their rules, some email applications and programs (such as gmail) classify messages sent sent via that route as advertising, so IMO they are less likely to be read, more likely to end up in addressee’s trash or spam folders.

This is what I did. I created a free newsletter in mailchimp. Then in my gmail, I created signatures with links and one of them is called “My Newsletter” or you can call it “Sign up for my Newsletter” or something like that. Then I emailed most of my buyers one by one and notified them of my latest paintings I have available. I then suggested that if they sign up for my newsletter, they can click the link below. (“My Newsletter”). Then if they sign up for the newsletter, it would be voluntary and you can send emails (newsletters) to them without breaking any rules.
However, if you just sent scheduled newsletters without them signing up voluntarily, it would be considered spamming according to mailchimp.
So your first email sent to them would not be a newsletter sent through mailchimp so that shouldn’t be any problem.
I don’t think there’s anything wrong with sending out an initial email asking someone to sign up anyway.
You can also include a widget for people to sign up for your newsletter on your blog, website or whatever. The widget you can get on from your mailchimp account.

Thanks everyone. What I ended up doing was creating a “Group” in gmail like Connie mentioned. The group includes email addresses of my collectors which can be added to as I get new collectors. I then sent an email at year end thanking them for their support in my artistic journey. I sent it as a bcc (blind carbon copy) to protect everyone’s privacy. As I grow and end up doing a regular newsletter, I will keep Bob’s suggestions about MailChimp in mind.

I use mailchimp as well. I believe Connie is right, a lot of it ends up in spam folder. I have seen some write ‘make sure you add ____ address to your accepted list so this doesn’t end up in yoru spam folder’ when people sign up to receive newsletter. I haven’t done that but meant to…