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WO2002018705A1 - Processus permettant de maitriser la clarte de papiers - Google Patents

Processus permettant de maitriser la clarte de papiers Download PDF

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Publication number
WO2002018705A1
WO2002018705A1 PCT/IB2001/001608 IB0101608W WO0218705A1 WO 2002018705 A1 WO2002018705 A1 WO 2002018705A1 IB 0101608 W IB0101608 W IB 0101608W WO 0218705 A1 WO0218705 A1 WO 0218705A1
Authority
WO
WIPO (PCT)
Prior art keywords
brightness
oba
paper
shading
direct
Prior art date
Application number
PCT/IB2001/001608
Other languages
English (en)
Inventor
Alec Stewart Tindal
Original Assignee
Clariant Finance (Bvi) Limited
Clariant International Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Clariant Finance (Bvi) Limited, Clariant International Ltd. filed Critical Clariant Finance (Bvi) Limited
Priority to BR0113569-4A priority Critical patent/BR0113569A/pt
Priority to EP01961018A priority patent/EP1315864A1/fr
Priority to KR1020037003136A priority patent/KR100800933B1/ko
Publication of WO2002018705A1 publication Critical patent/WO2002018705A1/fr

Links

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/26—Agents rendering paper transparent or translucent
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/28—Colorants ; Pigments or opacifying agents
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/30—Luminescent or fluorescent substances, e.g. for optical bleaching
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/71—Mixtures of material ; Pulp or paper comprising several different materials not incorporated by special processes
    • D21H17/72—Mixtures of material ; Pulp or paper comprising several different materials not incorporated by special processes of organic material

Definitions

  • This invention relates to a process for controlling the Brightness of paper products while using shading dyes.
  • Brightness is the technical term used to describe the reflectance of the paper or pulp at a specific wavelength, e.g. TAPPI Brightness, ISO Brightness etc.
  • CIE Whiteness and CIE Tint are calculated from the chromaticity co-ordinates and the color coordinates.
  • CIE Whiteness gives an impression of the whiteness of a sample including OBA and shading dye elements. The tint value is used to describe the particular shade of white. This gives fairly close correlation with the human eye and undoubtedly the best method of measuring whiteness available. In addition the Tint value is useful since two whites can have the same whiteness but have different shades.
  • CIE Whiteness and Tint are defined in ISO 11475 as:
  • W 10 Yio + 800(x n . ⁇ o -xio ) + 1700(y n . ⁇ o -yio)
  • T 900(x n . 10 -x.o ) - 650(y n l0 -yio)
  • the CIELAB L*, a*, b* values are used to describe color space, they are the three axis of a three dimensional system of describing a color.
  • L* represents the difference between black and white
  • a* is the red-green co-ordinate
  • b* is the blue yellow co-ordinate. They are particularly useful for describing and controlling the effect of shading dyes in white papers.
  • Another similar system is L, C, H where C and H represent the Chroma and the Hue. Whilst the a* and b* value are very useful for describing and controlling shade, the L* value again does not take into account shading dyes. When shading dyes are added the L* value is decreased. It should be noted also that OBA's effect a* and particularly b* values.
  • shading' dyes are not only added to achieve a whitening effect, but they are also added to control the color. Control of the color is often achieved through the use of a* and b* target values. This can be done manually, on-line or by on-line closed-loop color control. Violet and reddish blue dyes are used to improve whiteness, other colors are used to control the shade of the white paper, for example, reds, blues and yellows. Black colors are also used in very small amounts to control the opacity of white papers.
  • Brightness Brightness is a term used in the paper and pulp industry, which refers to a reflectance factor, usually around 460nm. It is defined in ISO 2470 and 3688, though there are other definitions (e.g. Scandinavian Pulp, Paper & Board testing committee SCAN-test Cl 1:75 & TAPPI standard test method T452). When small amounts of shading dye are added to white papers they reduce Brightness to a greater or lesser extent depending on the dye and concentration used. This occurs because dyes absorb light and therefore reduce reflectance. Optical Brighteners increase Brightness as they are fluorescent and therefore increase the Brightness value.
  • Optical brighteners are colorless to weakly colored organic compounds that, in solution or applied to a substrate, absorb ultraviolet light (e.g., from daylight at ca. 300 - 430 nm) and re-emit most of the absorbed energy as blue fluorescent light between ca. 400 and 500 nm.
  • ultraviolet light e.g., from daylight at ca. 300 - 430 nm
  • daylight optical brighteners can thus compensate for the aesthetically undesirable yellowish cast found in white industrial substrates, such as textiles, papers, or plastics. Furthermore, since a portion of the daylight spectrum not perceived by the eye is converted to visible light, the brightness of the material is enhanced to give a dazzling white.
  • the first method of compensating for the yellowish cast was the use of a blue dye such as ultramarine or indigo. Bluing lowers the reflectance of the sample in the long- wavelength part of the visible spectrum. As a result, the sample takes on a neutral white appearance, which appears more appealing to the eye.
  • a blue dye such as ultramarine or indigo. Bluing lowers the reflectance of the sample in the long- wavelength part of the visible spectrum. As a result, the sample takes on a neutral white appearance, which appears more appealing to the eye.
  • Optical brighteners lower the reflectance mainly in the UV and near visible by absorption; at visible wavelengths (mostly with a maximum at 435 - 440 nm), they greatly increase the Brightness through fluorescence.
  • the optical brightener acts as a supplementary emission source. Optical brighteners are more effective the cleaner and whiter the substrate is.
  • Fluorescence (usually obtained by measuring Brightness or Whiteness with UV component and subtracting the value measured without the UV component in the illuminant)
  • Reddish Violet Shading dye e.g. C.I. Direct Violet 51, C.I. Direct Blue 267
  • pigment e.g. C.I. Pigment Violet 23
  • Bluish/Neutral Violet Shading dye e.g. C.I. Direct Violet 35
  • pigment e.g. C.I. Pigment Blue 15, C.I. Pigment Violet 3
  • Red Shading dye (e.g. C.I. Direct Red 253): Used to adjust a* value, has a negative effect on Brightness and no effect on Whiteness, little or no effect on b* value,, no effect on fluorescence.
  • OBA e.g. C.I. Fluorescent Brightener 220, C.I. Fluorescent Brightener 28, C.I. Fluorescent Brightener 264): Used to increase Fluorescence and Whiteness and Brightness, also influences a* and b* values.
  • the color control in a white paper dyeing process is difficult to obtain.
  • concentration of the shading dye When increasing the concentration of the shading dye to achieve the correct color, the concentration of the OBA then has to be increased to obtain the right Brightness, since the increase in shading dye addition causes a decrease in Brightness.
  • This complicated and delicate procedure has to be done either manually or by closed loop color control.
  • the goal of the present invention is to provide an easier method to control the Brightness in paper products while using shading dyes by using a one step procedure which will help to save not only time but also reduce the necessary amount of the dyestuff and the OBA.
  • a process for shading white paper is provided, characterized in, that a mixture comprising at least one direct dye or pigment and at least one optical brightener is used.
  • the inventive process is characterized in that the mixture consists of one or more direct dyes and one or more optical brighteners in a ratio of 25/75 to 90/10 percent by weight, preferably 50/50 percent by weight.
  • a part of this invention is a mixture for adding fluorescence to shading dyes for paper comprising one or more direct dyes and one or more optical brighteners in a ratio of 25/75 to 90/10 percent per weight.
  • the OBA's for the present invention are Wet-end OBA's, Size-press OBA's and/or Coating OBA's.
  • Preferred OBA's are C.I. Fluorescent Brightener 220, C.I. Fluorescent Brightener 28 and/or C.I. Fluorescent Brightener 264.
  • Paper obtained by the inventive process is also a part of this invention.
  • the shading dye dosage can now be adjusted without affecting the Brightness value and allowing only one adjustment to be made, to the shading dye, without needing to also adjust the optical brightening agent dosage to regain Brightness.
  • OBA's for paper can be used.
  • Preferred optical brighteners are Wet-end OBA's (Leucophor ® AP, AL, U etc.), Size-press OBA's (Leucophor ® U, NS, SHR, TC etc) Coating OBA's (Leucophor ® U, AP, AL, NS, SHR, TC etc.).
  • Leucophor is a registered trademark of Clariant.
  • the OBA is added to the shading dye in the form of a mixture so that, when added to the paper the fluorescence of the OBA compensates for the loss in Brightness due to the absorbance of the dye and the Brightness of the paper is not reduced by the addition of the shading dye. Therefore process control is made more simple as only one component needs to be adjusted to achieve a color target and the Brightness is not reduced, therefore a compensatory adjustment of the OBA is not needed.
  • Pigments e.g. C.I. Pigment Violet 23, C.I. Pigment Blue 15, C.I. Pigment Violet 3 are also used in the shading of white papers (for example in coatings).
  • Shading dyes and OBA's are also used in size-press and coating applications as well as wet-end applications.
  • a standard preparation of paper stock consisting of 50% bleached softwood pulp and 50% bleached pulp are prepared at 20° Schopper Riegler, 20% CaCO 3 are added (ash by weight of dry fiber).
  • Handsheets are prepared from the above stock containing various amounts of a 1 : 1 mixture of a liquid anionic direct paper dye (containing 13% C.I. Direct Violet 35) and a mixture of a liquid optical brightening agent (containing 25% C.I. F. Br. 290) and, as a control a 50% dilution of the same liquid paper dye ( C.I. direct Violet 35).
  • a sizing agent is added (1.7% Aquapel ® 360X) and a retention aid is used to retain the chalk filler (0.003% Cartaretin ® 20CE).
  • the following additions are made of the dye and the dye/optical brightening agent-mixture, by weight of liquid product on dry fiber:

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  • Paper (AREA)

Abstract

La présente invention concerne un processus permettant d'ombrer du papier blanc qui consiste en un mélange comprenant au moins une teinte ou un pigment direct, et qui consiste à utiliser au moins un azureur optique. Cette invention concerne aussi ce mélange et ce papier teinté par ce procédé.
PCT/IB2001/001608 2000-09-01 2001-08-31 Processus permettant de maitriser la clarte de papiers WO2002018705A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BR0113569-4A BR0113569A (pt) 2000-09-01 2001-08-31 Processos para controlar o brilho de produtos de papel
EP01961018A EP1315864A1 (fr) 2000-09-01 2001-08-31 Processus permettant de maitriser la clarte de papiers
KR1020037003136A KR100800933B1 (ko) 2000-09-01 2001-08-31 종이 제품의 휘도를 조절하는 방법

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB0021404.9A GB0021404D0 (en) 2000-09-01 2000-09-01 Improvement in or to organic compounds
GB0021404.9 2000-09-01

Publications (1)

Publication Number Publication Date
WO2002018705A1 true WO2002018705A1 (fr) 2002-03-07

Family

ID=9898605

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2001/001608 WO2002018705A1 (fr) 2000-09-01 2001-08-31 Processus permettant de maitriser la clarte de papiers

Country Status (8)

Country Link
US (1) US20030188393A1 (fr)
EP (1) EP1315864A1 (fr)
KR (1) KR100800933B1 (fr)
CN (1) CN1279242C (fr)
BR (1) BR0113569A (fr)
GB (1) GB0021404D0 (fr)
WO (1) WO2002018705A1 (fr)
ZA (1) ZA200300347B (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011098237A1 (fr) 2010-02-11 2011-08-18 Clariant International Ltd Compositions aqueuses d'encollage pour le nuançage dans des applications à la presse encolleuse
WO2012000624A1 (fr) 2010-07-01 2012-01-05 Clariant International Ltd Compositions aqueuses de blanchiment et de nuançage dans les applications de revêtements
WO2012000625A1 (fr) 2010-07-01 2012-01-05 Clariant International Ltd Compositions aqueuses de nuançage dans les applications de revêtements
WO2012010326A1 (fr) 2010-07-23 2012-01-26 Clariant International Ltd Procédé pour préparer du papier blanc
EP2557128A1 (fr) 2011-08-11 2013-02-13 Clariant International Ltd. Compositions aqueuses améliorées pour le blanchiment et l'ombrage dans des applications de revêtement
US20210222369A1 (en) * 2018-05-18 2021-07-22 Stora Enso Oyj Coating composition for paper and paperboard

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1712677A1 (fr) * 2005-04-08 2006-10-18 Clariant International Ltd. Solutions aqueuses d'azurants optiques
US8246780B2 (en) * 2005-09-19 2012-08-21 Nalco Company Methods for enhancing brightness and resistance to thermal yellowing of bleached kraft pulp and paper
WO2007096242A1 (fr) * 2006-02-20 2007-08-30 Clariant International Ltd Procede ameliore de fabrication de papier et de carton
AR068223A1 (es) 2007-09-07 2009-11-11 Avery Dennison Corp Eiqueta para enmascarar, hoja de material para etiquetas y metodo relacionado
US9188889B2 (en) 2007-09-07 2015-11-17 Ccl Label, Inc. High opacity laser printable facestock
TW201000716A (en) * 2008-01-28 2010-01-01 Akzo Nobel Nv A method for production of paper
US9932709B2 (en) 2013-03-15 2018-04-03 Ecolab Usa Inc. Processes and compositions for brightness improvement in paper production
CN103911018B (zh) * 2014-03-21 2016-01-20 沈阳化工大学 一种制备直接红253的方法
JP7150491B2 (ja) * 2018-06-15 2022-10-11 キヤノン株式会社 画像処理システム、画像形成装置、画像処理装置、画像形成装置の制御方法、画像処理装置の制御方法、及びプログラム
CN111021137A (zh) * 2019-12-31 2020-04-17 山东华泰纸业股份有限公司 一种降低新闻纸白度提高不透明度的方法
WO2022221584A1 (fr) * 2021-04-14 2022-10-20 Kupka Todd Tapis d'apprentissage pour animal de compagnie avec signaux de stimulation visuelle pour animaux dichromatiques
CN115265788B (zh) * 2022-07-22 2025-03-28 中山火炬职业技术学院 一种针对纸张荧光增白剂的印前分色校正方法

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US4210488A (en) * 1977-10-13 1980-07-01 Reuss Peter J Process for improving the dry strength of paper and for improving the effect of optical brighteners in the preparation or coating of paper
US4842646A (en) * 1986-09-23 1989-06-27 Saranda Consolidated Limited Partnership Substantive dyes, inks and dye baths
US5064570A (en) * 1987-08-26 1991-11-12 Ciba-Geigy Corporation Dispersion fluorescent brightener preparations
US5131910A (en) * 1989-09-29 1992-07-21 Bayer (Canada) Inc. Method of coloring or tinting paper: adding red, yellow and blue dyes in selected proportions to base furnish
EP0853104A2 (fr) * 1997-01-14 1998-07-15 Clariant Finance (BVI) Limited Préparation tinctoriale liquide
US6030443A (en) * 1999-04-29 2000-02-29 Hercules Incorporated Paper coating composition with improved optical brightener carriers

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Publication number Priority date Publication date Assignee Title
US2762679A (en) * 1952-06-03 1956-09-11 Ohio Commw Eng Co Wood stain containing dextran dye
GB1313786A (en) * 1969-08-08 1973-04-18 Sandoz Ltd Process for the level dyeing and or optical brightening of paper
US4014870A (en) * 1974-06-12 1977-03-29 Ciba-Geigy Corporation Stilbene compounds
US4200489A (en) * 1977-08-26 1980-04-29 Ciba-Geigy Corporation Process for producing sized paper or cardboard with dyes or optical brighteners and epoxide-amine-polyamide reaction products
US4210488A (en) * 1977-10-13 1980-07-01 Reuss Peter J Process for improving the dry strength of paper and for improving the effect of optical brighteners in the preparation or coating of paper
US4842646A (en) * 1986-09-23 1989-06-27 Saranda Consolidated Limited Partnership Substantive dyes, inks and dye baths
US5064570A (en) * 1987-08-26 1991-11-12 Ciba-Geigy Corporation Dispersion fluorescent brightener preparations
US5131910A (en) * 1989-09-29 1992-07-21 Bayer (Canada) Inc. Method of coloring or tinting paper: adding red, yellow and blue dyes in selected proportions to base furnish
EP0853104A2 (fr) * 1997-01-14 1998-07-15 Clariant Finance (BVI) Limited Préparation tinctoriale liquide
US6030443A (en) * 1999-04-29 2000-02-29 Hercules Incorporated Paper coating composition with improved optical brightener carriers

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011098237A1 (fr) 2010-02-11 2011-08-18 Clariant International Ltd Compositions aqueuses d'encollage pour le nuançage dans des applications à la presse encolleuse
KR20180004330A (ko) * 2010-02-11 2018-01-10 아르크로마 아이피 게엠베하 사이즈 프레스 도포시의 조색을 위한 수성 사이징 조성물
US9797095B2 (en) 2010-02-11 2017-10-24 Archoma Ip Gmbh Aqueous sizing compositions for shading in size press applications
AU2011214619B2 (en) * 2010-02-11 2016-06-16 Archroma Ip Gmbh Aqueous sizing compositions for shading in size press applications
JP2013519742A (ja) * 2010-02-11 2013-05-30 クラリアント・ファイナンス・（ビーブイアイ）・リミテッド サイズプレス用途におけるシェーディングのための水性サイズ剤組成物
RU2563487C2 (ru) * 2010-02-11 2015-09-20 Клариант Финанс (Бви) Лимитед Водные проклеивающие композиции для изменения оттенка в сфере применения клеильного пресса
WO2012000624A1 (fr) 2010-07-01 2012-01-05 Clariant International Ltd Compositions aqueuses de blanchiment et de nuançage dans les applications de revêtements
WO2012000625A1 (fr) 2010-07-01 2012-01-05 Clariant International Ltd Compositions aqueuses de nuançage dans les applications de revêtements
US20130209821A1 (en) * 2010-07-01 2013-08-15 Clariant Finance (Bvi) Limited Aqueous Compositions For Whitening and Shading in Coating Applications
US8932727B2 (en) 2010-07-01 2015-01-13 Clariant Finance (Bvi) Limited Aqueous compositions for whitening and shading in coating applications
US8945718B2 (en) 2010-07-01 2015-02-03 Clariant Finance (Bvi) Limited Aqueous compositions for whitening and shading in coating applications
RU2564310C2 (ru) * 2010-07-01 2015-09-27 Клариант Финанс (Бви) Лимитед Водные композиции для отбеливания и тонировки при нанесении покрытий
RU2564815C2 (ru) * 2010-07-23 2015-10-10 Клариант Финанс (Бви) Лимитед Способ изготовления белой бумаги
WO2012010326A1 (fr) 2010-07-23 2012-01-26 Clariant International Ltd Procédé pour préparer du papier blanc
WO2013020693A1 (fr) 2011-08-11 2013-02-14 Clariant International Ltd Composition aqueuse améliorée pour le blanchiment et l'ombrage dans des applications de revêtement
EP2557128A1 (fr) 2011-08-11 2013-02-13 Clariant International Ltd. Compositions aqueuses améliorées pour le blanchiment et l'ombrage dans des applications de revêtement
US20210222369A1 (en) * 2018-05-18 2021-07-22 Stora Enso Oyj Coating composition for paper and paperboard

Also Published As

Publication number Publication date
KR100800933B1 (ko) 2008-02-04
EP1315864A1 (fr) 2003-06-04
GB0021404D0 (en) 2000-10-18
BR0113569A (pt) 2003-07-15
ZA200300347B (en) 2004-03-18
KR20030042458A (ko) 2003-05-28
CN1279242C (zh) 2006-10-11
US20030188393A1 (en) 2003-10-09
CN1464931A (zh) 2003-12-31

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