Exhibit (a)(1)(D)

Offer To Purchase For Cash

All Outstanding Shares of Common Stock

of

SOUTHWALL TECHNOLOGIES INC.

at

$13.60 NET PER SHARE

Pursuant to the Offer to Purchase dated October 25, 2011

by

BACKBONE ACQUISITION SUB, INC.

a wholly-owned subsidiary of

SOLUTIA INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON THE NIGHT OF TUESDAY, NOVEMBER 22, 2011, UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

October 25, 2011

To Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees:

We have been engaged by Backbone Acquisition Sub, Inc., a Delaware corporation (“Purchaser”) and a wholly-owned subsidiary of Solutia Inc., a Delaware corporation, to act as Information Agent in connection with Purchaser’s offer to purchase all outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Southwall Technologies Inc., a Delaware corporation (“Company”), at a purchase price of $13.60 per Share, net to the seller in cash, without interest, less any applicable withholding taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated October 25 2011 (as it may be amended or supplemented from time to time, the “Offer to Purchase”), and the related Letter of Transmittal (as it may be amended or supplemented from time to time, the “Letter of Transmittal” and, together with the Offer to Purchase, the “Offer”) enclosed herewith. Please furnish copies of the enclosed materials to those of your clients for whom you hold Shares registered in your name or in the name of your nominee.

Certain conditions to the Offer are described in Section 15 of the Offer to Purchase.

For your information and for forwarding to your clients for whom you hold Shares registered in your name or in the name of your nominee, we are enclosing the following documents:

1. The Offer to Purchase;

2. The Letter of Transmittal for your use in accepting the Offer and tendering Shares and for the information of your clients, which includes an IRS Form W-9 providing information relating to backup U.S. federal income tax withholding;

3. A Notice of Guaranteed Delivery to be used to accept the Offer if the Shares and all other required documents cannot be delivered to Computershare Trust Company, N.A. (the “Depositary”) by the expiration of the Offer or if the procedure for book-entry transfer cannot be completed by the expiration of the Offer;

4. A form of letter which may be sent to your clients for whose accounts you hold Shares registered in your name or in the name of your nominee, with space provided for obtaining such clients’ instructions with regard to the Offer;

5. A letter to stockholders of the Company from the Chairman of the Board of Directors of the Company, accompanied by the Company’s Solicitation/Recommendation Statement on Schedule 14D-9; and

6. A return envelope addressed to the Depositary for your use only.

We urge you to contact your clients as promptly as possible. Please note that the Offer and withdrawal rights will expire at 12:00 midnight, New York City time, on the night of Tuesday, November 22, 2011, unless the Offer is extended or earlier terminated.

For Shares to be properly tendered pursuant to the Offer, (a) the share certificates or confirmation of receipt of such Shares under the procedure for book-entry transfer, together with a properly completed and duly executed Letter of Transmittal, including any required signature guarantees, or an “Agent’s Message” (as defined in Section 3 of the Offer to Purchase) in the case of book-entry transfer, and any other documents required in the Letter of Transmittal, must be timely received by the Depositary or (b) the tendering stockholder must comply with the guaranteed delivery procedures, all in accordance with the Offer to Purchase and the Letter of Transmittal.

Purchaser will not pay any fees or commissions to any broker or dealer or other person (other than the Depositary and the Information Agent as described in the Offer to Purchase) for soliciting tenders of Shares pursuant to the Offer. Purchaser will, however, upon request, reimburse brokers, dealers, commercial banks and trust companies for reasonable and necessary costs and expenses incurred by them in forwarding materials to their customers. Purchaser will pay all stock transfer taxes applicable to its purchase of Shares pursuant to the Offer, subject to Instruction 6 to the Letter of Transmittal.

Any inquiries you may have with respect to the Offer should be addressed to, and additional copies of the enclosed materials may be obtained from, the undersigned at the address and telephone numbers set forth on the back cover of the Offer to Purchase.

Very truly yours,

D.F. King & Co., Inc.

Nothing contained herein or in the enclosed documents shall render you the agent of Purchaser, the Information Agent or the Depositary or any affiliate of any of them or authorize you or any other person to use any document or make any statement on behalf of any of them in connection with the Offer other than the enclosed documents and the statements contained therein.