<SEC-DOCUMENT>0001208109-17-000008.txt : 20170728
<SEC-HEADER>0001208109-17-000008.hdr.sgml : 20170728
<ACCEPTANCE-DATETIME>20170728162408
ACCESSION NUMBER:		0001208109-17-000008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170726
FILED AS OF DATE:		20170728
DATE AS OF CHANGE:		20170728

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GRAVES GREGORY B
		CENTRAL INDEX KEY:			0001208109

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32598
		FILM NUMBER:		17990304

	MAIL ADDRESS:	
		STREET 1:		3500 LYMNA BLVD
		CITY:			CHASKA
		STATE:			MN
		ZIP:			55318

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENTEGRIS INC
		CENTRAL INDEX KEY:			0001101302
		STANDARD INDUSTRIAL CLASSIFICATION:	PLASTICS PRODUCTS, NEC [3089]
		IRS NUMBER:				411941551
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		129 CONCORD ROAD
		CITY:			BILLERICA
		STATE:			MA
		ZIP:			01821
		BUSINESS PHONE:		9784366500

	MAIL ADDRESS:	
		STREET 1:		129 CONCORD ROAD
		CITY:			BILLERICA
		STATE:			MA
		ZIP:			01821
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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    <periodOfReport>2017-07-26</periodOfReport>

    <issuer>
        <issuerCik>0001101302</issuerCik>
        <issuerName>ENTEGRIS INC</issuerName>
        <issuerTradingSymbol>ENTG</issuerTradingSymbol>
    </issuer>

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            <rptOwnerCik>0001208109</rptOwnerCik>
            <rptOwnerName>GRAVES GREGORY B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4613 DREXEL AVE. S.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EDINA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55424</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP &amp; CFO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>900</value>
                </transactionShares>
                <transactionPricePerShare>
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    <derivativeTable>
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            </securityTitle>
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                <value>13.49</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-07-26</value>
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                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2022-02-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>900</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                <value>13.49</value>
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                <value>2017-07-27</value>
            </transactionDate>
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                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>18812</value>
                </transactionShares>
                <transactionPricePerShare>
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                </transactionAcquiredDisposedCode>
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                <footnoteId id="F3"/>
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                <value>2022-02-19</value>
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                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
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                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
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        </derivativeTransaction>
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    <footnotes>
        <footnote id="F1">These shares were sold pursuant to a Rule 10b5-1 Trading Plan established by the Reporting Person on May 12, 2017.</footnote>
        <footnote id="F2">The price in column 4 is a weighted average price reported in reliance on a letter from the Office of Chief Counsel, Securities and Exhcange Commission's Division of Corporate Secretaries &amp; Corporate Governance Professionals dated June 25, 2008. These shares were sold in multiple transactions at prices ranging from $26.00 to $26.75, inclusive. The Reporting Person undertakes to provide Entegris, Inc., any shareholder of Entegris, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this note.</footnote>
        <footnote id="F3">This option vests in four equal installments. The first two installments became exercisable on February 19, 2016 and February 19, 2017, respectively. The remaining installments become exercisable on February 19, 2018 and February 19, 2019, respectively.</footnote>
        <footnote id="F4">This option was granted pursuant to the Entegris, Inc. 2010 Stock Plan, as amended, in consideration of service as an employee.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Sue Lee, Attorney-In-Fact for Gregory B. Graves</signatureName>
        <signatureDate>2017-07-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</DOCUMENT>
</SEC-DOCUMENT>
