Infragistics, a company known for its .NET controls, announced on Tuesday Quince Pro, a new SaaS service for user interface design across teams.

Developers log into Quince Pro to create libraries containing user interface artifacts, such as screenshots and supportive documentation. Participants can be invited to access the library, and Silverlight 3-based collaboration tools are provided for workflows.

Quince’s annotation tools allow developers to comment and express ideas around what they are trying to show, said Jason Beres, director of product management at Infragistics. “As you update elements, people’s views change.”

Beres said Quince Pro is like an online SharePoint, only for designs. “[SharePoint is] for documents, with versioning and other tools that have their own way of commenting and expressing ideas.”

Quince Pro is an offshoot of Quince, a free online catalogue of UI patterns the company launched last year. Infragistics will continue to add new features to Quince.

Quince Pro is available as a 60-day trial. A subscription will be required at the end of Q1 2010, according to the company.