UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

~~Securities~~Date ~~Exchange~~of ~~Act~~Report (Date of ~~1934~~ earliest event reported): September 6, 2011

~~Date~~ARCH ofCHEMICALS, ~~Report~~INC. (~~Date~~Exact name of ~~earliest~~registrant ~~event~~as ~~reported):~~specified ~~August 5,~~in ~~2011~~its charter)

ARCH CHEMICALS, INC.

Virginia		1-14601		06-1526315
(State or other jurisdiction of incorporation)		(Commission File Number)		(IRS Employer Identification No.)

~~(Exact~~501 ~~name~~Merritt 7 Norwalk, CT 06851 (Address of ~~registrant~~principal asexecutive ~~specified~~offices, inzip ~~its~~code) ~~charter~~Registrant’s telephone number, including area code: (203) 229-2900

Virginia	1-14601	06-1526315
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)
501 Merritt 7, Norwalk, CT		06851
(Address of principal executive offices)		(Zip Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

~~Registrant’s~~□ ~~telephone~~Written ~~number,~~communications ~~including~~pursuant ~~area~~to ~~code:~~Rule 425 under the Securities Act (~~203) 229-2900~~17 CFR 230.425)

~~N/A~~□ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

~~(Former~~□ ~~name~~Pre-commencement orcommunications ~~former~~pursuant ~~address,~~to ifRule ~~changed~~14d-2(b) ~~since~~under ~~last~~the ~~report)~~Exchange Act (17 CFR 240.14d-2(b))

~~Check~~□ ~~the appropriate box below if the Form 8~~Pre-Kcommencement ~~filing~~communications ispursuant ~~intended~~ to ~~simultaneously~~Rule ~~satisfy~~13e-4(c) ~~the filing obligation of the registrant~~ under ~~any of~~ the ~~following~~Exchange ~~provisions~~Act (~~see~~17 ~~General~~CFR ~~Instruction A~~240.~~2. below~~13e-4(c): )

¨Item ~~Written~~5.02. ~~communications~~Departure ~~pursuant~~of toDirectors ~~Rule~~or ~~425~~Certain ~~under~~Officers; ~~the~~Election ~~Securities~~of ~~Act~~Directors; ~~(17~~Appointment ~~CFR~~of ~~230~~Certain Officers; Compensatory Arrangements of Certain Officers.~~425)~~

¨On ~~Soliciting~~September ~~material~~6, ~~pursuant~~2011, tothe ~~Rule~~Board ~~14a-12~~of ~~under~~Directors of Arch Chemicals, Inc. (the ~~Exchange~~“Company”) ~~Act~~adopted resolutions terminating the Company’s 1999 Long Term Incentive Plan and 2009 Long Term Incentive Plan (17together, ~~CFR~~the ~~240~~“LTIPs”), in each case contingent upon the consummation of the tender offer (the “Offer”) by LG Acquisition Corp.~~14a~~ (“Merger Sub”), a wholly-12owned subsidiary of Lonza Group Ltd. (“Lonza”), to purchase all of the outstanding shares of the Company’s common stock, par value $1.00 per share, at a price per share of $47.20 (the “Offer Price”) in cash pursuant to the agreement and plan of merger (the “Merger Agreement”), dated July 10, 2011, by and among Lonza, Merger Sub and the Company. Pursuant to the Merger Agreement, termination of the LTIPs must be completed prior to the consummation of the merger of Merger Sub with and into the Company, as contemplated by the Merger Agreement. Pursuant to the aforementioned resolutions, the LTIPs shall terminate upon the consummation of the Offer and, at such time, any and all rights and obligations of the Company, its subsidiaries and each of their respective officers and employees pursuant to the LTIPs (other than the rights of a participant therein to receive cash consideration based on the Offer Price in respect of the cancelation of such participant’s outstanding equity awards in accordance with the Merger Agreement) shall also terminate.

~~¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))~~Signatures

¨Pursuant ~~Pre-commencement communications pursuant~~ to ~~Rule~~the ~~13e-4(c)~~requirements ~~under~~of the Securities Exchange Act ~~(17~~of ~~CFR~~1934, ~~240~~the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.~~13e-4(c))~~

INFORMATION TO BE INCLUDED IN THE REPORT

	ARCH CHEMICALS, INC.

Date: September 12, 2011	By:	/s/ Joseph P. Lacerenza
		Name: Joseph P. Lacerenza
		Title: Sr. Deputy General Counsel and Corporate Secretary

ITEM 2.02. RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On August 5, 2011, Arch Chemicals, Inc. (the “Company”) released the results of operations and financial condition for the three and six months ended June 30, 2011. Attached as Exhibit 99, and incorporated herein by reference, is a copy of the Company’s earnings press release dated August 5, 2011.

Included in Exhibit 99 is a reference to the Company’s second quarter 2011 income and earnings per share from continuing operations which, as noted in such Exhibit, excludes a charge related to relocation costs. The Company believes that this non-GAAP financial measure provides a comparison of results to prior year and to the Company’s earnings guidance provided on May 4, 2011, and therefore is useful to the investment community. A reconciliation of this non-GAAP financial measure to what the Company believes is the most directly comparable U.S. GAAP financial measure is provided in such Exhibit.

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS

(d) Exhibits

99. Press Release, dated August 5, 2011.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: August 5, 2011

ARCH CHEMICALS, INC. By: /s/ Steven C. Giuliano Name: Steven C. Giuliano Title: Senior Vice President and Chief Financial Officer

Exhibit Index

Exhibit		Description
99.		Press Release, dated August 5, 2011.

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