<PAGE>   1
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-K

[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
    EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 1999
                          ------------------------------------------------------

                                       or

[  ] TRANSACTION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
     SECURITIES EXCHANGE ACT OF 1934

For the transition period from                          to
                              --------------------------   ---------------------

Commission file number 0-784
                      ----------------------------------------------------------


                               DETREX CORPORATION
--------------------------------------------------------------------------------
             (Exact name of registrant as specified in its charter)

           Michigan                                             38-0480840
           --------                                             ----------
 (State or other jurisdiction of                             (I.R.S. Employer
 incorporation or organization)                             Identification No.)

24901 Northwestern Hwy, Suite 500, Southfield, Michigan           48075
-------------------------------------------------------     --------------------
      (Address of principal executive offices)                  (Zip Code)

Registrant's telephone number, including area code            (248) 358-5800
                                                            --------------------

Securities registered pursuant to Section 12(b) of the Act:

                                                Name of each exchange on
Title of each class                                which registered
------------------------                        ---------------------------
      None                                              None

Securities registered pursuant to Section 12(g) of the Act:

                          Common Capital Stock, $2 Par Value
--------------------------------------------------------------------------------
                                (Title of Class)

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months and (2) has been subject to such filing requirements for
the past 90 days.
                                          Yes    X                NO
                                              -------               ---------

Indicate by a check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of the registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K. [X]


<PAGE>   2



                                                                       FORM 10-K

The aggregate market value (based upon the NASDAQ Closing Price) of Common
Capital Stock on March 17, 2000 of Detrex Corporation held by nonaffiliates was
approximately $4,948,169 million.


The number of shares of Common Capital Stock, $2 Par Value, outstanding on March
17, 2000 was 1,583,414.

Documents incorporated by reference:

<TABLE>
<CAPTION>

                                                           Part and Item Number
                                                            of Form 10-K into
               Document                                     which Incorporated
               --------                                     ------------------

<S>                                                       <C>
1.       Detrex Corporation                                 Part II Items 5 through 8
         Annual Report to                                   Part IV, Item 14
         Shareholders for the year
         ended December 31, 1999

2.       Detrex Corporation                                 Part III, Items 10, 11, 12
         Notice of Annual                                   and 13
         Meeting of Shareholders
         and Proxy Statement for
         the Annual Meeting of
         Shareholders to be held
         April 27, 2000


</TABLE>


                                                                               2


<PAGE>   3



                                                                       FORM 10-K

                                     PART I

ITEM 1. BUSINESS

Detrex Corporation was incorporated in Michigan in 1925. Detrex Corporation and
its subsidiaries (the Company) operate predominantly in chemicals and allied
products, services, and supply processes for use by manufacturing and service
industries and is comprised of the following operations:

Detrex Corporation

     -     Solvents and Equipment Divisions - provide solutions for production
           parts cleaning needs, including equipment, solvents, recycling of
           waste, and contract parts cleaning

Subsidiaries of Detrex Corporation

     -     Harvel Plastics, Inc. - manufacturer of high quality PVC and CPVC
           pipe and custom extrusions


     -     The Elco Corporation - manufacturer of high performance specialty
           chemicals including lubricant additives, fine chemicals, and
           semi-conductor grade hydrochloric acid

     -     Seibert-Oxidermo, Inc. - supplier of primers and functional coatings
           for the automotive industry

Net sales by product line for each of the last five years are set forth below:

<TABLE>
<CAPTION>
                                                              Product Line
                                                     ------------------------------
                                                      Chemical
                                                       Products          Chemical
                                                     and Services        Equipment            Total
                                                     ------------      ------------      -------------
<S>                                                <C>                <C>               <C>
                  1999                                $84,921,659      $  5,494,176      $  90,415,835
                  1998                                 77,914,813         8,124,464         86,039,277
                  1997                                 83,466,537        12,290,264         95,756,801
                  1996                                 78,017,582        18,807,854         96,825,436
                  1995                                 77,698,771        16,603,228         94,301,999
</TABLE>


Of the $85 million included in 1999 Chemical Products and Services sales,
approximately $14.5 million (17%) represent sales by the Company's solvents
division, $13.5 million (16%) represent sales by its paint subsidiary, $19.9
million (23%) represent sales by its lubricants subsidiary, $35.7 million (42%)
represent sales by its plastic pipe subsidiary and $1.4 million (2%) represent
sales of other related chemical products and services. For additional
information regarding the operating segments of the Company, see Note 15 to the
Consolidated Financial Statements.


                                                                               3
<PAGE>   4


                                                                       FORM 10-K

                               PART I (CONTINUED)

ITEM 1. BUSINESS (Continued)

The backlog of orders at any one time is generally not significant to the
Company's business. At December 31, 1999, the Company's backlog of equipment
orders was approximately $800,000 and the Company expects to complete all of
these orders in the first half of 2000.

Raw materials essential to the Company's various products are generally
commodity materials and are readily available from competitive sources. The
Company's Solvents Division is continuing to go through a major transition in
the marketplace, primarily because of the phasing out of certain ozone depleting
solvents and other regulatory actions. As a result, the division is increasingly
marketing substitutes for such solvents, including aqueous based cleaners, is
expanding its permits to enable it to handle more waste codes, and is becoming
involved in the parts cleaning business.

The Company owns various patents and trademarks which aid in maintaining the
Company's competitive position; these expire at various times within the next
seventeen years. The expiration of such patents and trademarks should not have a
material adverse effect on the Company's operations. No material portion of the
Company's business is seasonal or subject to renegotiation of profits or
termination of contracts or subcontracts at the election of the government.

The approximate dollar amounts spent during 1999, 1998, and 1997 on research
sponsored by the Company were $1,286,000, $1,243,000 and $1,365,000,
respectively. The number of professional employees engaged in such activities
were 12 for 1999, 14 for 1998, and 16 for 1997.

There are no customers to which sales were made in an amount which equals ten
percent or more of consolidated revenues.

The Company does not expect to incur significant capital expenditures for
environmental compliance in 2000. However, the Company does expect to continue
to incur significant professional fees and expenses in connection with its
environmental compliance efforts. The Company maintains an environmental reserve
which at December 31, 1999 totaled $7.3 million, of which $1.5 million is
estimated to be spent in 2000. A more detailed discussion of environmental
matters is included under Item 3 - Legal Proceedings and in Management's
Discussion and Analysis in the Annual Report.

The Company employed 327 persons as of December 31, 1999.

The Company is not engaged in manufacturing operations in foreign countries. For
information regarding sales by customer location, see Note 15 to the
Consolidated Financial Statements.


                                                                               4
<PAGE>   5


                                                                       FORM 10-K

                               PART I (CONTINUED)

ITEM 1. BUSINESS (Concluded)

The Company utilized a combination of internally generated funds, the proceeds
from the sale of a closed plant and increased borrowings to finance its
activities during 1999. As of December 31, 1999, working capital was $3.7
million compared to $5.9 million at December 31, 1998. For a discussion of the
Company's Credit Agreement, see Note 5 to the Consolidated Financial Statements
and Management's Discussion and Analysis in the Annual Report.

The Company has market risks which could arise from fluctuations in interest
rates under both its Credit Agreement and the Industrial Development Bonds
issued by the California Economic Development Financial Authority. (see Notes 5
and 6 to the Consolidated Financial Statements). A 1% increase in the prime
interest rate could impact the Company's pretax earnings by approximately
$100,000 and a 1% increase in tax-exempt bond interest rates could affect pretax
earnings by a maximum of $35,000.

ITEM 2. PROPERTIES

The Company's administrative offices are located in approximately 7,500 square
feet of leased space at 24901 Northwestern Hwy., Suite 500, Southfield,
Michigan.

Detrex and its subsidiaries conduct manufacturing and research operations in
numerous locations of which ten are owned as follows:

1) Facilities located on 57 acres in Ashtabula, Ohio are used in connection with
the manufacture of hydrochloric acid, reagent grade chemicals, fine chemicals
including pharmaceutical intermediates, N-methyl pyrrole, and zinc-based
lubricant additives.

2) The Company's lubricants subsidiary, The Elco Corporation, manufactures gear
and oil additives in a plant located in Cleveland, Ohio on 5 acres of land and
59,000 square feet of office, research and plant space. This plant is equipped
with mixing and blending equipment and storage facilities.

3) The Company's plastic pipe subsidiary, Harvel Plastics, Inc. ("Harvel"),
manufactures plastic pipe in a plant located on 20 acres of land and 228,500
square feet of office and plant space located in Easton, Pennsylvania. Extruders
and special dies are used to manufacture the plastic PVC pipe from resin.
Production and warehouse facilities have been expanded several times since this
subsidiary was acquired in 1968.

     Harvel expanded its manufacturing capacity in 1998 by leasing a new 100,000
square feet facility in California, which was built to suit Harvel's warehouse
and manufacturing needs. The lease term is for an initial period of fifteen
years expiring in the year 2013, with provision for three five-year extensions.

4) Seibert-Oxidermo, Inc. manufactures primers and functional coatings for the
automotive industry in a plant located in Romulus, Michigan containing 45,000
square feet of office, research and plant space on 40 acres of land.
In addition, Seibert maintains a warehouse facility in Detroit, Michigan.


                                                                               5

<PAGE>   6



                                                                       FORM 10-K

                               PART I (CONTINUED)

ITEM 2. PROPERTIES (Concluded)


5) The Company owns a building used as a research laboratory and office in
Bowling Green, Kentucky. In addition, the company owns a separate building in
Bowling Green for its parts cleaning operations.

6) The Company owns a warehouse and sales office facility located in Detroit,
Michigan. The building area is approximately 20,000 square feet and is located
on approximately one-half acre of land.

7) The Company owns a warehouse and sales office facility located in Los
Angeles, California. The building area is approximately 10,000 square feet and
is located on one acre of land in the industrial section of the city.

8) The Company owns a warehouse and sales office facility located in Charlotte,
North Carolina. The building area is approximately 11,000 square feet and is
located on one acre of land.

9) The Company owns a warehouse and sales office facility located in
Indianapolis, Indiana. The building area is approximately 8,600 square feet and
is located on one acre of land.

10) The company owns a warehouse and sales office facility located in Chicago,
Illinois. The building area is approximately 10,000 square feet and is located
on one acre of land.


ITEM 3. LEGAL PROCEEDINGS

The Company and at least seventeen other companies are potentially responsible
for sharing the costs in a proceeding to clean up contaminated sediments in the
Fields Brook watershed in Ashtabula, Ohio. The Environmental Protection Agency
('EPA') issued a Record of Decision in 1986 concerning the methods it recommends
using to accomplish this task. The Company and the other potentially responsible
parties negotiated with the EPA as to how best to effect the clean up operation.
After negotiation, an agreement was reached with the EPA on clean-up
methodology. The Company's share of clean-up costs is anticipated to be in the
range of approximately $2.5 million.

The Company maintains a reserve for anticipated expenditures over the next
several years in connection with remedial investigations, feasibility studies,
remedial design, and remediation relating to the clean up of environmental
contamination at several sites, including properties owned by the Company. The
amounts of the reserve at December 31, 1999 and 1998 were $7.3 million and $8.0
million, respectively. The reserve includes a provision for the Company's
anticipated share of remediation in the Fields Brook watershed referred to
above, as well as a provision for costs that are expected to be incurred in
connection with remediation of other sites. Some of these studies have been
completed; others are ongoing. In some cases, the methods of remediation remain
to be agreed upon.


                                                                               6

<PAGE>   7



                                                                       FORM 10-K

                               PART I (CONTINUED)

ITEM 3. LEGAL PROCEEDINGS (Concluded)


The Company expects to continue to incur professional fees, expenses and capital
expenditures in connection with its environmental compliance efforts. In
addition to the above, there are several claims and lawsuits pending against the
Company and its subsidiaries. The Company expects to continue to incur
professional fees, expenses and capital expenditures in connection with its
environmental compliance efforts. In addition to the above, there are several
other claims and lawsuits pending against the Company and its subsidiaries. One
of those lawsuits involves the division of costs between several potentially
responsible companies for reimbursement to the EPA for costs it incurred to
conduct environmental remediation at a drum and barrel recycler, which the
Company had utilized several years ago. The potentially responsible companies
entered into an Agreement to, among other things, jointly defend the cost claims
of the EPA. A dispute arose amongst the potentially responsible companies over
the Agreement which resulted in the filing of a lawsuit. The matter went to
trial before a jury in June of 1999 and a judgment was entered against the
Company in the amount of approximately $750,000, plus interest and attorney
fees. The Company is taking an appeal to the Michigan Court of Appeals and
believes it has reasonable grounds to seek reversal of the judgment.

         The amount of liability to the Company with respect to costs of
remediation of contamination of the Fields Brook watershed and of other sites,
and the amount of liability with respect to several other claims and lawsuits
against the Company, was based on available data. The Company has established
its reserves in accordance with its interpretation of the principles outlined in
Statement of Financial Accounting Standards No. 5 and Securities and Exchange
Commission Staff Accounting Bulletin No. 92. In the event that any additional
accruals should be required in the future with respect to such matters, the
amounts of such additional accruals could have a material impact on the results
of operations to be reported for a specific accounting period but should not
have a material impact on the Company's consolidated financial position.



ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

No matter was submitted to a vote of security holders during the fourth quarter
of the fiscal year covered by this report.



                                                                               7

<PAGE>   8




                                                                       FORM 10-K

                               PART I (CONTINUED)

EXECUTIVE OFFICERS OF THE REGISTRANT

The names and ages of all executive officers of the registrant at March 24, 2000
and their positions and offices with the registrant are as follows:

<TABLE>
<CAPTION>
                  Name and Age                                         Positions and Offices
                  ------------                                         ---------------------

<S>                                 <C>                      <C>
W. C. King                          (55)                      Chairman and Chief Executive Officer (a)

T. E. Mark                          (47)                      President and Chief Operating Officer (b)

G. J. Israel                        (59)                      Vice President - Finance, Treasurer and Chief
                                                              Financial Officer (c)

R. M. Currie                        (46)                      Secretary and General Counsel (d)

S. J. Quinlan                       (36)                      Controller (e)
</TABLE>


(a) Mr. King joined the Company as President and Chief Executive Officer in
April 1995. He was elected Chairman of the Board in January 1996. Prior to
joining the Company, Mr. King was President and Chief Operating Officer of
Masland Industries from 1992 to 1994 and prior to that, Vice President and Group
Executive of Allied Signal.

(b) Mr. Mark joined the Company as President and Chief Operating Officer in
January 1996. Prior to that he was President and General Manager of ABB Paint
Finishing from 1990 to 1996.

(c) Mr. Israel was elected Vice President - Finance and Chief Financial Officer
on February 25, 1993 and Treasurer in 1994. Mr. Israel came to the Company from
Chrysler Corporation where he served for 26 years in numerous financial
positions. His most recent position was Vice President and Controller-Treasurer
of Chrysler Canada Ltd.

(d) Mr. Currie joined the Company as General Counsel on July 16, 1993. He was
named Secretary and General Counsel on November 1, 1994. Prior to joining the
Company, Mr. Currie was engaged in private law practice.

(e) Mr. Quinlan served as a Division Controller for the Company for more than
five years before being elected Controller on April 23, 1998.

All officers of the Company are elected annually and hold office until their
successors are chosen and qualify in their stead.



                                                                               8

<PAGE>   9



                                                                       FORM 10-K
                                     PART II
                              CROSS REFERENCE SHEET

<TABLE>
<CAPTION>
                                                      Page (and caption) in 1999 Detrex Corporation
                  10-K Item                                  Annual Report to Shareholders*
                  ---------                                  ------------------------------
<S>      <C>                                         <C>
5.       Market for Registrant's Common
         Stock and Related Shareholder Matters:

         (a)  Market and market prices
                of the common stock                           15- Selected Quarterly Data
         (b)  Approximate number of
                holders of common stock                        - Highlights
         (c)  Dividend history                                14- Management's Discussion and
                                                                    Analysis of Financial Condition
                                                                    and Results of Operations

6.       Selected Financial Data                              16- Selected Financial Data

7.       Management's Discussion and                          13-14 -  Management's Discussion and
         Analysis of Financial Condition                               Analysis of Financial Condition
         and Results of Operations                                     and Results of Operations

8.       Financial Statements and Supplementary
         Data:
         -        Detrex Corporation Consolidated
                  Balance Sheets, December 31,
                  1999 and 1998                                4,5
         -        Consolidated Statements of
                  Operations and Retained Earnings
                  for the Years Ended December 31,
                  1999, 1998, and 1997                         3
         -        Consolidated Statements of Cash
                  Flows for the Years Ended
                  December 31, 1999, 1998, and 1997            6
         -        Notes to Consolidated Financial
                  Statements                                   7-12
         -        Independent Auditors' Report                 2

         With the exception of the aforementioned information and the
         information incorporated by reference in Items 5, 6 and 7, the Annual
         Report to Shareholders is not to be deemed filed as part of this
         Form 10-K Annual Report.

9.       Changes in and Disagreements with
         Accountants on Accounting and
         Financial Disclosure                                 Not Applicable
</TABLE>


* Detrex Corporation's Annual Report to Shareholders for the year ended December
31, 1999 is incorporated herein as Exhibit 13 under Item 14(a) 3 of Part IV.


                                                                               9

<PAGE>   10
                                                                       FORM 10-K

                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

The information required by Item 10 is incorporated by reference from the
information set forth under the caption "Election of Directors" in the Detrex
Corporation Proxy Statement (the "Proxy Statement") for the Annual Meeting of
Shareholders to be held April 27, 2000. The information required for Executive
Officers of the Company is included in Part I hereof.

ITEM 11. EXECUTIVE COMPENSATION

The information required by Item 11 is incorporated by reference from the
information set forth under the caption "Executive Compensation and Other
Transactions" in the Proxy Statement.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND
         MANAGEMENT

The information required by Item 12 is incorporated by reference from the
information set forth under the caption "Election of Directors" in the Proxy
Statement.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

The information required by Item 13 is incorporated by reference from the
information set forth under the captions "Election of Directors" and "Executive
Compensation and Other Transactions" in the Proxy Statement.




                                                                              10

<PAGE>   11


                                                                       FORM 10-K

                                    PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS
         ON FORM 8-K

(a) 1.  All Financial Statements

        Detrex Corporation and Subsidiaries (incorporated by reference
        to the Company's Annual Report to Shareholders for the year
        ended December 31, 1999-see Part II)

(a) 2.  Financial Statement Schedules                                Page

        Independent Auditors' Report                                  15

        Schedule II - Valuation and Qualifying
        Accounts for the Years Ended December 31,
        1999, 1998, and 1997.                                         16


                                                                              11

<PAGE>   12
                                                                       FORM 10-K

                               PART IV (CONTINUED)

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS
         ON FORM 8-K (Continued)

<TABLE>
<CAPTION>
(a) 3.   Exhibits

<S>                                                                                            <C>
         3(i)     Articles of Incorporation, as amended, are hereby                             --
                  incorporated by reference to Commission file #0-784,
                  Annual Report on Form 10-K for the year ended
                  December 31, 1987, as Exhibit 3(a)

         3(ii)    Bylaws, as amended, are hereby incorporated by                                --
                  reference to Commission file #0-784, Annual
                  Report Form 10-K for the year ended
                  December 31, 1997, as Exhibit 3(ii)

         4        Shareholders Rights Plan is hereby incorporated by                            --
                  reference to Commission file #0-784 8-K Report dated
                  May 4, 1990, as Exhibit 4

                  Executive Compensation Plans and Arrangements

         10(a)    1993 Stock Option Plan is hereby incorporated by reference to                 --
                  Commission file # 0-784 1993 Proxy Statement dated
                  March 26, 1993, as Exhibit 10(a)

         10(b)    1993 Stock Option Plan for outside directors is hereby                        --
                  incorporated by reference to Commission file #0-784 1993
                  Proxy Statement dated March 2, 1993, as Exhibit 10(b)

         10(d)    Employment Agreement - Gerald J. Israel, is hereby                            --
                  incorporated by reference to Commission file # 0-784
                  Annual Report on Form 10-K for the year ended
                  December 31, 1992 as Exhibit 10(h)
</TABLE>



                                                                              12

<PAGE>   13


                                                                       FORM 10-K

                               PART IV (CONTINUED)

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS
         ON FORM 8-K (Continued)

<TABLE>
<CAPTION>
(a) 3.   Exhibits (Continued)


<S>                                                                                            <C>
         10(e)    Employment Agreement - Robert M. Currie, is hereby                            --
                  incorporated by reference to Commission file #0-784
                  Annual Report on Form 10-K for the year ended December 31,
                  1994, as Exhibit 10(g)

         10(f)    Temporary Employment Agreement - William C. King, is hereby                   --
                  incorporated by reference to Commission file #0-784
                  Annual Report on Form 10-K for the year ended December 31,
                  1995, as Exhibit 10(i)

         10(g)    Employment Agreement - William C. King, is hereby                             --
                  incorporated by reference to Commission file #0-784
                  Annual Report on Form 10-K for the year ended December 31,
                  1995, as Exhibit 10(j)

         10(h)    Employment Agreement - Thomas E. Mark, is hereby                              --
                  incorporated by reference to Commission file #0-784
                  Annual Report on Form 10-K for the year ended December 31,
                  1995, as Exhibit 10(k)
                                                                                                --


                  Other Material Contracts

         10(i)    Credit Agreement with Comerica Bank dated as of                               --
                  June 13, 1996, (the "Credit Agreement"), is hereby
                  incorporated by reference to Commission file #0-784
                  Quarterly Report on Form 10-Q for the quarter ended
                  June 30, 1996, as Exhibit 10(p)

         10(j)    First Amendment to Credit Agreement, dated                                    --
                  December 5, 1996, is hereby incorporated by reference to
                  Commission file #0-784 Annual Report on Form 10-K for
                  the year ended December 31, 1996 as Exhibit 10(o)
</TABLE>


                                                                              13


<PAGE>   14



                                                                       FORM 10-K
                               PART IV (CONCLUDED)

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS
                  ON FORM 8-K (Concluded)
<TABLE>
<CAPTION>

(a)      3.       Exhibits (Concluded)
<S>                                                                                            <C>
         10(k)    Second Amendment to the Credit Agreement, dated as of                         --
                  March 31, 1997 is hereby incorporated by
                  reference to Commission file #0-784 Quarterly Report on Form
                  10-Q for the quarter ended March 31, 1997, as Exhibit 10(q)

         10(l)    Third Amendment to the Credit Agreement, dated                                --
                  April 22, 1998 is hereby incorporated by reference to
                  Commission file #0-784 Quarterly Report on Form 10-Q for
                  the quarter ended March 31, 1998 as Exhibit 10(o)

         10(m)    Fourth Amendment to the Credit Agreement, dated                               --
                  March 15, 1999 is hereby incorporated by reference to
                  Commission file #0-784 Annual Report on Form 10-K for the
                  Year ended December 31, 1998 as Exhibit 10(m)

         10(n)    Fifth Amendment to the Credit Agreement, dated May 20, 1999                   --
                  is hereby incorporated by reference to Commission file #0-784
                  Quarterly Report on Form 10-Q for the quarter ended June 30,
                  1999 as Exhibit 10(n)

         10(o)    Sixth Amendment to the Credit Agreement, dated                                Attached as
                  February 29, 2000                                                             an Exhibit

         13       Annual Report to Shareholders for the year ended December 31, 1999            Attached as
                                                                                                an Exhibit

         21       Subsidiaries of the Registrant                                                Attached as
                                                                                                an Exhibit

         23       Consent of Auditors                                                           Attached as
                                                                                                an Exhibit

         27       Financial Data Schedule                                                       Attached as
                                                                                                an Exhibit
(b)      A report was filed on Form 8-K on December 14, 1999 announcing the
         closing of a manufacturing plant of The Elco Corporation, a subsidiary
         of the Registrant.
</TABLE>


                                                                              14

<PAGE>   15










                       DETREX CORPORATION AND SUBSIDIARIES

                          FINANCIAL STATEMENT SCHEDULES







<PAGE>   16


INDEPENDENT AUDITORS' REPORT

To the Board of Directors and Stockholders of
Detrex Corporation:

We have audited the consolidated financial statements of Detrex Corporation and
its subsidiaries (the "Company") as of December 31, 1999 and 1998, and for each
of the three years in the period ended December 31, 1999, and have issued our
report thereon dated March 1, 2000; such consolidated financial statements and
report are included in your Annual Report to Shareholders for the year ended
December 31, 1999 and are incorporated herein by reference.  Our audits also
included the financial statement schedule of the Company, listed in Item 14(a)
(2).  This financial statement schedule is the responsibility of the Company's
management.  Our responsibility is to express an opinion based on our audits.
In our opinion, such financial statement schedule, when considered in relation
to the basic consolidated financial statements taken as a whole, presents fairly
in all material respects the information set forth therein.


/s/ Deloitte & Touche LLP
-------------------------
Deloitte & Touche LLP


Detroit, Michigan
March 1, 2000




<PAGE>   17
                                                                       FORM 10-K

                                                                     SCHEDULE II

DETREX CORPORATION AND SUBSIDIARIES

VALUATION AND QUALIFYING ACCOUNTS
FOR THE YEARS ENDED DECEMBER 31, 1999, 1998 AND 1997

<TABLE>
<CAPTION>

                                                      Additions
                                              -----------------------
                                Balance       Charged to     Charged                   Balance
                                Beginning     Costs and      to Other                  at End
         Description             of Year      Expenses       Accounts   Deductions     of Year
         -----------            ---------     ----------    ---------   ----------     -------

Year Ended December 31, 1999

<S>                             <C>           <C>            <C>        <C>           <C>
Inventory Valuation Reserves     $221,438      187,214                     193,649    $227,873

Finished Machines Valuation
Reserves                         $251,418                      34,755       24,945    $241,608

Allowance for Uncollectible
Accounts                         $249,368      115,000                     120,100    $244,268


Year Ended December 31, 1998

Inventory Valuation Reserves     $264,190      182,363                     225,115    $221,438

Finished Machines Valuation
Reserves                         $247,007                      14,586       10,176    $251,418

Allowance for Uncollectible
Accounts                         $371,569      158,000                     280,201    $249,368

Year Ended December 31, 1997

Inventory Valuation Reserves     $176,909      272,713                     185,432    $264,190

Finished Machines Valuation
Reserves                         $343,307                      63,470      159,770    $247,007

Allowance for Uncollectible
Accounts                         $394,599      145,721                     168,751    $371,569
</TABLE>
<PAGE>   18
                                                                       FORM 10-K

                                   SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange
Act of 1934, the Registrant has duly caused this report to be signed on its
behalf by the undersigned, thereunto duly authorized.

                                                    Detrex Corporation
                                        ----------------------------------------
                                                      (Registrant)

         Date  March 27, 2000           By  W. C. King
                                            ------------------------------------
                                            W. C. King
                                            Chairman and Chief Executive Officer

Pursuant to the requirements of the Securities Exchange Act of 1934, this report
has been signed below on this twenty-seventh day of March 2000 by the following
persons on behalf of the Registrant and in the capacities indicated.

                  Signature                       Title


         W. C. King                      Chairman and Chief Executive
-------------------------------          Officer
         W. C. King

         T. E. Mark                      President and Chief Operating
-------------------------------          Officer
         T. E. Mark

         G. J. Israel                    Vice President, Treasurer and
-------------------------------          Chief Financial Officer
         G. J. Israel

         S. J. Quinlan                   Controller and Chief Accounting
-------------------------------          Officer
         S. J. Quinlan

         B. W. Cox                       Director
-------------------------------
         B. W. Cox

         R. A. Emmett, III               Director
-------------------------------
         R. A. Emmett, III

         J. F. Mangold                   Director
-------------------------------
         J. F. Mangold

         B. W. McCleary                  Director
-------------------------------
         B. W. McCleary

         A. R. Thalacker                 Director
-------------------------------
         A. R. Thalacker

         J. D. Withrow                   Director
-------------------------------
         J. D. Withrow

         D. R. Zimmer                    Director
-------------------------------
         D. R. Zimmer



<PAGE>   19
                                 Exhibit Index


<TABLE>
<CAPTION>
Exhibit No.         Description
-----------         -----------
<S>                 <C>
    10(o)           Sixth Amendment to the Credit Agreement,
                    dated February 29, 2000

    13              Annual Report to Shareholders for the year ended
                    December 31, 1999

    21              Subsidiaries of the Registrant

    23              Consent of Auditors

    27              Financial Data Schedule
</TABLE>




<PAGE>   20


                      DETREX CORPORATION AND SUBSIDIARIES

                                    EXHIBITS