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
  • D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
  • D21H27/18—Paper- or board-based structures for surface covering
  • D21H27/22—Structures being applied on the surface by special manufacturing processes, e.g. in presses
  • D21H27/26—Structures being applied on the surface by special manufacturing processes, e.g. in presses characterised by the overlay sheet or the top layers of the structures
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B44—DECORATIVE ARTS
  • B44C—PRODUCING DECORATIVE EFFECTS; MOSAICS; TARSIA WORK; PAPERHANGING
  • B44C5/00—Processes for producing special ornamental bodies
  • B44C5/04—Ornamental plaques, e.g. decorative panels, decorative veneers
  • B44C5/043—Ornamental plaques, e.g. decorative panels, decorative veneers containing wooden elements
• • 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
  • D21H17/375—Poly(meth)acrylamide
• • 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
  • D21H17/41—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups
  • D21H17/42—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups anionic
  • D21H17/43—Carboxyl groups or derivatives thereof
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31725—Of polyamide
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31855—Of addition polymer from unsaturated monomers
  • Y10T428/3188—Next to cellulosic
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31855—Of addition polymer from unsaturated monomers
  • Y10T428/3188—Next to cellulosic
  • Y10T428/31895—Paper or wood
  • Y10T428/31899—Addition polymer of hydrocarbon[s] only
  • Y10T428/31902—Monoethylenically unsaturated
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31855—Of addition polymer from unsaturated monomers
  • Y10T428/3188—Next to cellulosic
  • Y10T428/31895—Paper or wood
  • Y10T428/31906—Ester, halide or nitrile of addition polymer

Definitions

• the invention relates to a method for producing a prepreg, which with this Method received pre-impregnate and its use for the production of decorative composite structures. Furthermore, the invention relates to the impregnation of the prepreg used impregnating liquor.
• EP 0 223 922 A method of the kind described in the beginning is apparent from EP 0 223 922.
• This Patent describes a process for the preparation of synthetic resins in the form of solutions and dispersions impregnated paper webs.
• the impregnating liquid is a mixture from aqueous anionic copolymer dispersions based on acrylic acid, acrylic ester, Acrylonitrile, vinyl acetate and / or styrene and from aqueous anionic solutions of copolymers based on maleic anhydride or maleic acid with styrene, Acrylic acid and acrylic acid esters used.
• WO 94/00523 discloses an aqueous impregnating solution impregnated with papers which are then used to make laminate panels.
• the aqueous impregnating solution contains 5 to 90 parts by weight of polyvinyl alcohol to 10 to 95 parts by weight of a Dispersion of an ethyl styrene / acrylate / butyl acrylate copolymer.
• it is a low-formaldehyde Prepreg.
• it is at the confluence of unfavorable temperatures and Lack systems not sufficiently stable against yellowing. Under yellowing here is not one Lack of light resistance are understood, but the chemical reaction, the takes place due to the impregnating liquor used.
• the well-known prepreg finds due to this yellowing in the so-called "white” area little application. Under "white” area, the expert understands bright laminates or furniture parts in which a Yellowing is particularly disadvantageous.
• the invention had the object to provide a pre-impregnate, all has desirable properties of the prepreg described above, simultaneously but no yellowing tendency shows.
• this object is achieved with a method for producing a Preimpregnate solved, which is characterized in that a base paper with a Impregnated impregnating liquor, the a) an aqueous dispersion based on a Acrylate / styrene copolymer.
• a dry strength agent based on a copolymer of (meth) acrylamide and (meth) acrylic acid and c) water wherein pro Part by weight of dry copolymer of (meth) acrylamide and (meth) acrylic acid about 0.3 to 13 parts by weight of dry acrylic acid ester / styrene copolymer are used, the viscosity the impregnating liquor (according to DIN 53211) to 10 to 18 sec and the solids content of Impregnating liquor is adjusted to 15 to 50 wt .-% and the freeness of the used raw paper has been adjusted to 18 to 50 ° RS.
• pre-impregnate is a term known to the person skilled in the art technicus.
• the pre-impregnate is, as mentioned above, by impregnating a Base paper obtained with an impregnating liquor. Then it is dried. It lies then in the form of a resin-impregnated fiber material - in technical language use also foil called - before and is brought to the market. Depending on the desired end use it can be further modified.
• the pH of the impregnating liquor used is preferably in the range of 4.5 to 8.0, especially in the range of 5.0 to 5.5.
• the setting of the desired pH can be carried out with sodium hydroxide solution and sulfuric or hydrochloric acid. Too high a pH may cause instability of the dispersion, too low a pH may under certain circumstances damage the fibers.
• the viscosity (measured according to DIN 53211) of the impregnating liquor is 10 to 18 sec, in particular 11 to 14 sec.
• the solids content of the impregnating liquor varies depending on the application product 15 to 50 wt .-%. A solids content of about 30% by weight is preferred because of it a desirable degree of impregnation of the nonwoven fabric is achieved.
• the acrylic acid ester of the acrylic ester / styrene copolymer may be methyl, Ethyl, n-buryl, i-buryl and 2-ethylhexyl esters, with the use of n-butyl acrylate is preferred.
• Acronal S 305 D® is one 50% aqueous dispersion of a copolymer based on n-butyl acrylate and styrene.
• the acrylic acid ester / styrene copolymer is in the form of a film.
• the Minimum film-forming temperature is preferably in the range of 5 to 70 ° C, especially in the range of 10 to 30 ° C.
• the dry strength agent is preferably a copolymer of acrylamide and acrylic acid with anionic charge. Compared with a dry strength agent on Basis of a copolymer of methacrylamide and methacrylic acid with anionic charge The use of a copolymer based on acrylamide and acrylic acid leads to less brittle products.
• the dry strength agent itself has a solids content of 15 to 30%, in particular from 20 to 22%, a pH betting in the range of 6.0 to 9.0, a viscosity from 100 to 300 mPa.s (Brookfield, 20 ° C) and a density of about 1.0 g / ml 20 ° C.
• the dry strength agent should be used in the paper pulp in order to develop properties described below.
• the dry strength agent Forming polymer bridges, he solidifies the paper structure, without disturbing the formation of sheets or to influence the porosity. This means that all mechanical Strength properties of the paper can be improved.
• the paper type achieves improvements in tenacity and burst strength as well the tear strength and the gap strength of the paper. This allows, depending on Quality requirements, the use of low-cost raw materials, a higher ash content of raw paper and saving of tools. As a side effect shows up a significant improvement in retention.
• Long fiber and short fiber pulps can be used as fiber raw materials.
• the substance input of the prepreg raw paper is not significantly different from that of the Decorative papers.
• the long fiber content is 0 to 40%, in particular 15 to 30% the short fiber content 60 to 100%, in particular 60 to 85%.
• the degree of grinding of the Raw paper is also variable and is between about 18 and 50 ° SR, in particular between 25 and 35 ° SR.
• the ash content of the raw paper is dependent on the respective used paper between 2 to 40%, in particular between 10 to 30%.
• the settings in the paper machine such as. B. speed, wet press, Temperature curve, contact pressure at the Yankee cylinder, are of the type and quality of the used Pandas different and are within the constraints of papermaking varied and optimized. To control retention, post-breakage loads and pH commercially available products, such as aluminum sulfate used.
• property-modifying additives such as. B. pH regulators, Wet and dry strength agents, synthetic resin dispersions, precipitants (Fixiermictel), Surfactants, Dyes, Fillers, Curing, Viscosity Control, Non-stick and Penetrationsangesmittel and pigments to add the impregnating solution
• the impregnation of the raw paper to the prepreg is carried out with a paper-based system carried out.
• a paper-based system carried out.
• Machine parts such as unwinding, size press, dryer section, steam humidifier, smoothness value and Paperoller winding.
• the pre-impregnate can be used both on-line and off-line getting produced.
• "On-line” means that the size press, with the the impregnating liquor is applied, is arranged in the paper machine while under "off-line” is understood that the size press in a separate operation behind or is used after the paper machine. In the latter case, the pre-impregnate is at the end the paper machine not as a finished product but as a semi-finished product before. this leads to important parameters such as color, porosity, smoothness and final basis weight, either readjusted in the laboratory or recalculated from experience Need to become.
• the impregnating liquor can be applied to one side but also to both sides of the base paper become. If the impregnating liquor is applied to one side, then the training is the surface of the screen side of the base paper of importance, including a control of Temperature curve of the pre-dryer group of the paper machine is extremely important. at impregnation on both sides, the impregnation can be complete, d. H. she can in penetrate the entire paper pulp. The total intake of impregnating liquor through the raw paper depends on the type of raw paper, but also after the Pressing off the excess impregnating liquor from the paper web.
• the prepreg according to the invention has the advantage that it does not lead to a yellowing of the further processing products when applied leads. This is due to the fact that the component of the glyoxal / urea precondensate by a dry strength agent based on a copolymer (Meth) acrylamide and (meth) acrylic acid was replaced with weak anionic charge.
• a dry strength agent based on a copolymer (Meth) acrylamide and (meth) acrylic acid was replaced with weak anionic charge.
• the Dry strength agent is usually used in the mass and leads to physical a fiber strengthening, which improves the dry strength in the end product, not against the wet strength. This shows that the dry strength agent is only physically fiber bonding acts and the fiber structure is not solidified by chemical reaction.
• the prepreg according to the invention can be used for the production of decorative composite structures become.
• decorative laminates with the inventive Preimpregnate be prepared. They are applying heat and pressure and suitable glue systems produced in presses or laminating plants. Especially be chipboard and medium-density fibreboard (MDF boards) on both sides with the coated prepreg according to the invention.
• the prepreg also serves as decor-carrying component.
• the prepreg according to the invention offers itself.
• the inventive Foil can have any wood grain or any fantasy decor.
• the pre-impregnate can be painted. To be used especially transparent coatings, such. As acrylate, acid-curing, water-soluble and pigmented paints. In addition to the protective function of the paint gives this the pre-impregnate also a corresponding visual impression.
• a base paper of the following composition was produced: 20% pine sulfate pulp and 80% eucalyptus pulp. The freeness was 31 ° SR (Schopper-Riegler). As additives (on otro pulp) 30% titanium dioxide and 4% formaldehyde-free wet strength used.
• the dispersion alone has poor splitting resistance shows.
• the dry strength agent alone forms insufficient water resistance and tends to increase poor gap strength.
• the impregnating liquor according to the invention leads to good Water resistance and sufficient splitting strength, as well as Formulation 4.
• the Impregnating liquor 3 according to the invention in contrast to recipe 4, has a significantly lower content Yellow shift (db value) after heat treatment.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Paper (AREA)
• Laminated Bodies (AREA)
• Reinforced Plastic Materials (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=7834415

Family Applications (1)

Country Status (7)

Families Citing this family (12)

Family Cites Families (10)

• 1997
  • 1997-07-02 DE DE19758479A patent/DE19758479C2/de not_active Expired - Lifetime
• 1998
  • 1998-04-27 EP EP98107656A patent/EP0889168B1/de not_active Expired - Lifetime
  • 1998-05-11 CZ CZ19981454A patent/CZ292989B6/cs not_active IP Right Cessation
  • 1998-06-25 US US09/104,106 patent/US6113987A/en not_active Expired - Lifetime
  • 1998-06-30 PL PL327120A patent/PL196113B1/pl unknown
  • 1998-06-30 CA CA002240011A patent/CA2240011C/en not_active Expired - Lifetime
  • 1998-07-01 BR BRPI9802621-6A patent/BR9802621B1/pt not_active IP Right Cessation
• 2000
  • 2000-04-13 US US09/548,144 patent/US6312827B1/en not_active Expired - Lifetime

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