-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 MjF9+fTz/LCWPfvKN4CIofT3lqX2dL3NNGUbPeCFw0embNjpOYcJ2J44haPd06R+
 Vy+CNrRz1KnRYGMnfVssvQ==

<SEC-DOCUMENT>0001181431-03-012116.txt : 20030701
<SEC-HEADER>0001181431-03-012116.hdr.sgml : 20030701
<ACCEPTANCE-DATETIME>20030630185001
ACCESSION NUMBER:		0001181431-03-012116
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030626
FILED AS OF DATE:		20030701

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SIEGEL RICHARD W
		CENTRAL INDEX KEY:			0001195154

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22333
		FILM NUMBER:		03765969

	MAIL ADDRESS:	
		STREET 1:		1319 MARQUETTE DR
		CITY:			ROMEOVILLE
		STATE:			IL
		ZIP:			60441

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NANOPHASE TECHNOLOGIES CORPORATION
		CENTRAL INDEX KEY:			0000883107
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS PRIMARY METAL PRODUCTS [3390]
		IRS NUMBER:				363687863
		STATE OF INCORPORATION:			IL
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		453 COMMERCE ST
		CITY:			BURR RIDGE
		STATE:			IL
		ZIP:			60521
		BUSINESS PHONE:		6303231200

	MAIL ADDRESS:	
		STREET 1:		453 COMMERCE STREET
		CITY:			BURR RIDGE
		STATE:			IL
		ZIP:			60521
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd12017.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0101</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-06-26</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000883107</issuerCik>
        <issuerName>NANOPHASE TECHNOLOGIES CORPORATION</issuerName>
        <issuerTradingSymbol>NANX</issuerTradingSymbol></issuer>
<reportingOwner>
<reportingOwnerId>
            <rptOwnerCik>0001195154</rptOwnerCik>
            <rptOwnerName>SIEGEL RICHARD W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>1</isDirector>
<isOfficer>0</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle></officerTitle>
<otherText></otherText></reportingOwnerRelationship></reportingOwner>
<nonDerivativeSecurity>
<securityTitle>
<value>Common Stock</value></securityTitle>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionTimeliness>
<value></value></transactionTimeliness>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>200527</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>0.112</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>1995-02-15</value>
<footnoteId id="F1"/></exerciseDate>
<expirationDate>
<value>2004-02-15</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>14475</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>14475</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>0.432</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>1996-02-01</value>
<footnoteId id="F1"/></exerciseDate>
<expirationDate>
<value>2005-02-01</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>17370</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>17370</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>1.727</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>1997-03-01</value>
<footnoteId id="F1"/></exerciseDate>
<expirationDate>
<value>2006-03-01</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>13896</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>13896</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>3.886</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>1997-11-07</value>
<footnoteId id="F2"/></exerciseDate>
<expirationDate>
<value>2006-11-07</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>23160</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>23160</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>5.250</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>1999-06-10</value>
<footnoteId id="F3"/></exerciseDate>
<expirationDate>
<value>2008-06-10</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>2000</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>2000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>3.8125</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>1999-07-31</value>
<footnoteId id="F1"/></exerciseDate>
<expirationDate>
<value>2008-07-31</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>11600</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>11600</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>9.920</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>2002-06-05</value>
<footnoteId id="F3"/></exerciseDate>
<expirationDate>
<value>2011-06-05</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>2000</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>2000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>3.780</value></conversionOrExercisePrice>
<transactionDate>
<value>1988-08-08</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>0</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>2003-11-25</value>
<footnoteId id="F3"/></exerciseDate>
<expirationDate>
<value>2012-11-25</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>2000</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>2000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Common Stock (right to buy)</value></securityTitle>
<conversionOrExercisePrice>
<value>5.07</value></conversionOrExercisePrice>
<transactionDate>
<value>2003-06-26</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>2000</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>2004-06-26</value>
<footnoteId id="F3"/></exerciseDate>
<expirationDate>
<value>2013-06-26</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>2000</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>2000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<footnotes>
<footnote id="F1">Subject to certain restrictions, beginning on this date, the options vest in five equal annual installments.</footnote>
<footnote id="F2">Subject to certain restrictions, 19,177 of these options vest in five equal annual installments beginning on 11/7/97, with the remainder vesting on 11/7/04.</footnote>
<footnote id="F3">Subject to certain restrictions, beginning on this date, the options vest in three equal annual installments.</footnote></footnotes>
<ownerSignature>
<signatureName>By Jess Jankowski, under UPA, for Richard W. Siegel</signatureName>
<signatureDate>2003-06-30</signatureDate></ownerSignature></ownershipDocument>


</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----