EP0764741A2 - Staubfreies Papier - Google Patents

Staubfreies Papier Download PDF

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Publication number
EP0764741A2
EP0764741A2 EP96306636A EP96306636A EP0764741A2 EP 0764741 A2 EP0764741 A2 EP 0764741A2 EP 96306636 A EP96306636 A EP 96306636A EP 96306636 A EP96306636 A EP 96306636A EP 0764741 A2 EP0764741 A2 EP 0764741A2
Authority
EP
European Patent Office
Prior art keywords
dust
glass transition
paper
emulsion
range
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP96306636A
Other languages
English (en)
French (fr)
Other versions
EP0764741A3 (de
Inventor
Kunihide Takarabe
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rohm and Haas Co
Original Assignee
Rohm and Haas Co
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 Rohm and Haas Co filed Critical Rohm and Haas Co
Publication of EP0764741A2 publication Critical patent/EP0764741A2/de
Publication of EP0764741A3 publication Critical patent/EP0764741A3/de
Withdrawn legal-status Critical Current

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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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20—Macromolecular organic compounds
    • D21H17/33—Synthetic macromolecular compounds
    • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/36—Polyalkenyalcohols; Polyalkenylethers; Polyalkenylesters
    • 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
    • D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
    • D21H27/16—Pure paper, i.e. paper lacking or having low content of contaminants
    • 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
    • D21H17/20—Macromolecular organic compounds
    • D21H17/33—Synthetic macromolecular compounds
    • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/35—Polyalkenes, e.g. polystyrene
    • 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
    • D21H17/20—Macromolecular organic compounds
    • D21H17/33—Synthetic macromolecular compounds
    • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/37—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates

Definitions

  • This invention relates to dust-free paper, and more particularly this invention intends to provide dust-free paper to be used in clean room, etc. which excels in stiffness and blocking resistance, prepared by including in the paper a polymer composition containing two different polymeric substances having specific and different glass transition temperatures (Tg).
  • Tg glass transition temperatures
  • Papers made of cellulose pulp and contained polymeric substance have been used in the past to improve heat resistance, solvent resistance, and water resistance, and they are used widely also to prevent formation of dust.
  • the invention disclosed in Japanese Patent Publication (Kokai) 146099/85 relates to dust-free paper which was impregnated or coated with a polymeric substance having a minimum film-forming temperature of no higher than 10°C.
  • the polymeric substances that are used in that invention are emulsion or latex formed from polyacrylate, polyvinyl acetate, and polyvinylchloride type copolymers. Specific examples are the emulsion of polyvinyl acetate, polyacrylate, and polyvinyl acetate/ethylene/acrylate copolymer.
  • Japanese Patent Publication (Kokai) 105199/88 discloses a preparation method of dust-free paper, by impregnating or coating a hollow pigment, together with synthetic resins having a glass transition temperature of no higher than 0°C, such as polyacrylate, polyvinyl acetates or polyethylene or latex, in paper.
  • Japanese Patent Publication (Kokai) 167996/75 discloses a dust-free paper prepared by adding a polymeric substance having glass transition temperature of no higher than 0°C in paper.
  • the polymeric substance are emulsion of acrylic ternary copolymer, acrylate ester polymer, and vinyl acetate/acrylic acid copolymer, which is impregnated in paper by dipping. It demonstrates that the amount of dust generated from the paper decreases as the glass transition temperature decreases, and that the amount of dust formed will be extremely small particularly when the Tg is -50°C.
  • the real problem is as follows.
  • the amount of dust generated will be extremely small when a polymeric substance having low glass transition temperature, and particularly when the glass transition temperature in -40°C ⁇ -50°C is included in the paper made of cellulose pulp, such paper tends to show excessively high blocking property and lower stiffness.
  • the paper may show stiffness when the glass transition temperature is in 0°C ⁇ -20°C range, there is no reduction in the amount of dust formed. Therefore, there is a demand for a dust-free paper that is equipped with both characteristics, i.e. a dust-free paper with stiffness and blocking resistance.
  • This invention provides a composition for dust-free paper comprising a polymer composition which contains a polymeric substance having a glass transition temperature (Tg) in -20°C ⁇ 70°C range and a polymeric substance having glass transition temperature (Tg) in -65°C ⁇ 10°C range, where the difference of the glass transition temperatures of the polymeric substances is 30°C or above, preferably 50°C or above, and most desirably 70°C or above, and the average glass transition temperature (tg) is in -30°C ⁇ 20°C range, preferably in -20°C ⁇ -10°C range.
  • the mixing ratio of the polymeric substance having glass transition temperature (Tg) in -20°C ⁇ 70°C range and the polymeric substance having a glass transition temperature (Tg) in -65°C ⁇ 10°C range is preferably in 20:80 ⁇ 80:20 range, more preferably in 70:30 ⁇ 30:70 range.
  • This invention further provides a dust-free paper on which the above-said composition for dust-free paper was carried.
  • composition for dust-free paper of this invention is mixed with a dust free at 3 weight % ⁇ 100 weight %, preferably 5 weight % ⁇ 50weight %, by the weight of the paper.
  • Dust-free paper with excellent paper stiffness and blocking resistance can be obtained by using the composition for dust-free paper composition of this invention.
  • any of the natural polymers and synthetic polymers can be used as the polymeric substance in this invention.
  • Example of natural polymer is natural rubber, and examples of synthetic polymeric substance are synthetic rubber; polymers and copolymers obtained by polymerizing ethylenic unsaturated monomers such as ethylene, propylene, vinyl chloride, vinyl acetate, styrene, acrylonitrile, methacrylonitrile, acrylates, methacrylate, acrylic acid, or methacrylic acid; and diene monomers such as butadiene or isoprene, etc.
  • polyethylenically unsaturate monomers such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, divinylbenzene, trimethylol propane trimethacrylate and allyl methacrylate can be incorporated.
  • the polymeric substance having glass transition temperature (Tg) in -20°C ⁇ 70°C range is a hard component and the polymeric substance having glass transition temperature (Tg) in -65°.C ⁇ 10° C range is a soft component.
  • Preferred range of the Tg of the hard component is -10°C ⁇ 50°C, and 0°C ⁇ 40°C range is even more desirable.
  • preferred range of the Tg of soft component is -55°C ⁇ -10°C, and -55 °C ⁇ -35°C range is even more desirable.
  • Glass transition temperature of the hard component is higher than the glass transition temperatures of the soft component by more than 30°C, preferably more than 50°C. And a difference of more than 70°C is even more desirable.
  • a plurality of polymers can be used for the hard component and the soft component, as long as each of them meets the above-said requirements.
  • the average glass transition temperature (tg) of the hard component and soft component is in -30°C ⁇ 20 °C range, preferably in -20°C ⁇ -10°C range. If the average glass transition temperature is lower, the paper will not be as stiff and the blocking property will be poor. On the other hand, if the average glass transition temperature is higher, it generates more dust, which is not desirable.
  • W 1 and W 2 are weight fraction of the component 1 and component 2
  • Tg(1) and Tg(2) represent, respectively, the glass transition temperature (unit : absolute temperature) of the homopolymer of component 1 and homopolymer of component 2.
  • W 1 , and W 2 are weight fractions of homopolymer or copolymer components 1 and 2, respectively, and Tg(1) and Tg(2) represent the glass transition temperature (unit: absolute temperature) of the polymer component 1 and polymer component 2.
  • DSC differential scanning calorimetry
  • Average glass transition temperature may be determined by analyzing for monomer and calculating using the Fox's equation.
  • Table 1 shows the glass transition temperatures of typical polymers used in the invention.
  • Table 1 Polymer Tg (°C) Polymethyl acrylate 13 Polyethyl acrylate -17 Poly(n-butyl acrylate) -45 Poly(s-butyl acrylate) -18 Poly(2-ethylhexyl acrylate) -65 Polyhydroxyethyl acrylate -15
  • Polyacrylic acid 110 Polymethacrylic acid 155 Polymethyl methacrylate 83 Polyethyl methacrylate 55 Poly(n-butyl methacrylate) 20 Poly(i-butyl methacrylate) 20 Polyhydroxyethyl methacrylate 55 Polyhydroxypropyl methacrylate 73
  • Polyglycidylmethyl methacrylate 46 Polyacrylamide 165 Polyacryl nitrile 140 Polyvinyl chloride 80 Polyvinyl acetate 33 Polybutadiene -83 Polystyrene 83 Polyitaconic acid 165
  • Mixing ratio of the hard polymeric substance and soft polymeric substance may be changed preferably in 20:80 ⁇ 80:20 range, more preferably in 70:30 ⁇ 30:70 range, assuming that the average glass transition temperature is in -30°C ⁇ 20°C range.
  • Soft polymer'component and hard polymer component can be prepared by any of the known methods.
  • polymer components are used as an aqueous solution, solvent solution, or as an emulsion, and emulsion form is used preferably.
  • the method of preparing first the emulsions of each polymeric substances and then mixing the polymer emulsions together to form the film-forming composition for dust-free paper of this invention is the most simple and convenient method.
  • core/shell polymer i.e. a polymer having an inner core phase of a polymeric substance and an outer shell phase of polymeric substance
  • this core/shell polymer can be prepared by a known production process, it is particularly desirable to provide such core/shell polymer as an emulsion produced by multiple stage emulsion polymerization process. For example, it is obtained by forming first the core phase using the above-said ethylenic unsaturated monomer, and subsequently forming the outer shell phase using another ethylenic unsaturated monomer.
  • the core phase or shell phase may be made of a hard component, it is generally desirable to use a hard component as the core phase and soft component as the shell phase.
  • the internally plasticized polymer latex particles in which a hard polymer is copolymerized to the soft polymer latex particle may be used also.
  • Such internally plasticized polymer latex particles can be prepared by polymerizing the first charge of ethylenically unsaturated monomer that contains a relatively hydrophilic monomer in emulsion under ordinary condition of emulsion polymerization, and subsequently polymerizing the second charge of ethylenically unsaturated monomer which is the precursor of a polymer which is harder and more hydrophobic than the first charge polymer.
  • the present'invention provides a method for producing dust-free paper wherein a polymer composition is prepared by mixing a polymer substance having a glass transition temperature (Tg) in a range of -20°C to 70°C and another polymer substance having a glass transition temperature (Tg) in a range of -65°C to 10°C, a difference between their glass transition temperatures being 30°C or above, and an average glass transition temperature (tg) being in a range of -30°C to 20°C, at a ratio of 95:5 to 5:95, and the produced composition for dust-free composition is carried on paper.
  • Tg glass transition temperature
  • Tg glass transition temperature
  • Tg glass transition temperature
  • paper made of wood material or paper made mainly of wood pulp
  • paper made of regenerated fiber such as rayon
  • semisynthetic paper such as acetate paper
  • synthetic paper made of polyvinyl alcohol, polyamide, polyacrylonitrile or polyester
  • synthetic pulps made of polyethylene or polypropylene can be used.
  • These paper stock may be added ahead of time with various types of additives such as sizing agent, pigment, drying enhancement agent, wet strength-enhancement agent and so on. These additives may be added at the same time when the composition for dust-free paper of this invention is carried on paper.
  • the amount of the composition for dust-free paper to be mixed is normally 3 weight % ⁇ 100 weight %, preferably 5 weight % ⁇ 50 weight %, and even more desirably 10 ⁇ 30 weight %, by the weight of paper.
  • any known ordinary agent to enhance the dust-preventing effect such as electrically conductive salts, wax, etc. may be used, and it may be applied after a proper dilution.
  • any known method may be used to carry the composition for dust-free paper of this invention in or on paper.
  • it may be carried by impregnation method, size press method, spray method, or coating method in an impregnator or on a paper making machine, or it may be carried on paper after the paper was made.
  • Nonionic surfactant 7g and deionized water 340g were charged in a 3 liter flask equipped with an agitator, a thermometer, a reflex condensor and a N2 gas inlet port, and nitrogen gas was sparged.
  • deionized water 17g containing ammonium persulfate 0.20g as the initiator, deionized water 17g containing sodium hydrosulfite 0.16g, and deionized water 10g containing ferrous sulfate 0.02g were added, to initiate the polymerization reaction.
  • Tg is determined as a temperature at the midpoint of heat capacity change due to glass transition.
  • Example 1-1) Procedure of Example 1-1) was repeated, except setting the composition of the pre-emulsion to have deionized water 550g, nonionic surfactant 70g, itaconic acid 25g, butyl acrylate 944g, and ethyl acrylate 48g.
  • Emulsion 1 and Emulsion 2 were blended at the following ratios, to obtain Emulsion 3, Emulsion 4, and Emulsion 5.
  • Emulsion 1/Emulsion 2 550/450
  • Emulsion 1/Emulsion 2 620/380
  • Emulsion 1/Emulsion 2 700/300
  • Nonionic surfactant 7g and deionized water 320g were charged in a 3 liter flask equipped with an agitator, a thermometer, a reflux condensor and a N 2 gas inlet port, and nitrogen gas was sparged.
  • deionized water 17g containing ammonium persulfate 0.20g as the initiator deionized water 17g containing sodium hydrosulfite 0.16g, and deionized water 10g containing ferrous sulfate 0.02g were added, to initiate the polymerization reaction.
  • deionized water 28g containing ammonium persulfate 0.9g, and deionized water 28g containing sodium bisulfite 1.3g were added over a period of 2 hours. During addition, temperature was kept at 60°C.
  • reaction mixture was kept for 30 minutes, and then a pre-emulsion containing deionized water 245g, nonionic surfactant 32g, itaconic acid 12g, butyl acrylate 425g, and ethyl acrylate 22g, deionized water 14g containing ammonium persulfate 0.5g, and deionized water 14g containing sodium bisulfite 0.7g were added over a period of 1 hour. During the course of addition, temperature was kept at 60°C.
  • a paper stock cut into A-4 size was dipped in a bath where the concentration of emulsion was 13% for impregnation, and then the excess emulsion was removed by passing the wet paper through a set of two rubber rolls, so that the content of acrylic resins (based on the weight of the original paper stock) would be 15 weight %. subsequently, it was dried for 3 minutes on a chrome plated steam drum whose surface temperature was set at 90°C.
  • Tester Total number (per cubic feet) of particles having a size 0.3 ⁇ m or above was counted with Dustcounter of a light-scattering particle counter (manufactured by Lyon Co.), to evaluate the cleanliness. Lower value showed a better cleanliness.
  • Paper stiffness was tested by the procedure described in TAPPI (1991 Edition, T451 cm-84). Evaluation was based on the following grading standard.
  • Blocking resistance was measured by the procedure described in TAPPI (1991 Edition, T521 cm-85). Evaluation was based on the following grading standard.
  • the dust-free paper of this invention forms very little amount of dust, and excels in paper stiffness and blocking resistance. Therefore, the dust-free paper of this invention can be used in broad area such as the recording paper for various types of equipments, writing paper, or printed matters which are to be used in a clean room.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Paper (AREA)
  • Paints Or Removers (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
EP96306636A 1995-09-21 1996-09-12 Staubfreies Papier Withdrawn EP0764741A3 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP7266197A JPH0987993A (ja) 1995-09-21 1995-09-21 無塵紙
JP266197/95 1995-09-21
JP26619795 1995-09-21

Publications (2)

Publication Number Publication Date
EP0764741A2 true EP0764741A2 (de) 1997-03-26
EP0764741A3 EP0764741A3 (de) 1999-10-06

Family

ID=17427617

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96306636A Withdrawn EP0764741A3 (de) 1995-09-21 1996-09-12 Staubfreies Papier

Country Status (9)

Country Link
EP (1) EP0764741A3 (de)
JP (1) JPH0987993A (de)
KR (1) KR970015923A (de)
AU (1) AU6577496A (de)
BR (1) BR9603830A (de)
CA (1) CA2186072A1 (de)
IL (1) IL119253A0 (de)
MX (1) MX9604189A (de)
TW (1) TW322519B (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6815010B2 (en) * 2000-05-31 2004-11-09 Rohm and Naas Company Method of inhibiting the loss of solar reflectance over time of an exterior elastomeric
EP1007578B2 (de) † 1997-08-28 2010-04-28 Cray Valley S.A. Thermoplastischer hydrophober film

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5008127B2 (ja) * 2007-02-02 2012-08-22 北越紀州製紙株式会社 無塵紙

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4478974A (en) * 1980-05-21 1984-10-23 The Dow Chemical Company Heterogeneous polymer latex of relatively hard and relatively soft interpolymers of a monovinylidene aromatic monomer and an aliphatic conjugated diene monomer
US4806207A (en) * 1987-02-15 1989-02-21 The Dow Chemical Company Structured latex particles having reinforcing and opacity characteristics
ES2072298T3 (es) * 1988-05-16 1995-07-16 Mitsui Toatsu Chemicals Emulsion agregada de particulas finas, proceso para la elaboracion de la mencionada emulsion, medios de registro termico, papel recubierto y pintura que incorpora la mencionada emulsion.
ATE101887T1 (de) * 1988-10-21 1994-03-15 Dow Chemical Co Papierprodukt, hergestellt mit strukturierten latexteilchen mit verstaerkenden und opaken eigenschaften und verfahren zu seiner herstellung.

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1007578B2 (de) † 1997-08-28 2010-04-28 Cray Valley S.A. Thermoplastischer hydrophober film
US6815010B2 (en) * 2000-05-31 2004-11-09 Rohm and Naas Company Method of inhibiting the loss of solar reflectance over time of an exterior elastomeric

Also Published As

Publication number Publication date
CA2186072A1 (en) 1997-03-22
EP0764741A3 (de) 1999-10-06
BR9603830A (pt) 1998-06-02
IL119253A0 (en) 1996-12-05
MX9604189A (es) 1997-03-29
AU6577496A (en) 1997-03-27
TW322519B (de) 1997-12-11
KR970015923A (ko) 1997-04-28
JPH0987993A (ja) 1997-03-31

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