EP3377235A1 - Structure de laque multicouche présentant un catalyseur thermolatent - Google Patents

Structure de laque multicouche présentant un catalyseur thermolatent

Info

Publication number
EP3377235A1
EP3377235A1 EP16802006.3A EP16802006A EP3377235A1 EP 3377235 A1 EP3377235 A1 EP 3377235A1 EP 16802006 A EP16802006 A EP 16802006A EP 3377235 A1 EP3377235 A1 EP 3377235A1
Authority
EP
European Patent Office
Prior art keywords
basecoat
clearcoat
polyisocyanate
substrate
film
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Withdrawn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
EP16802006.3A
Other languages
German (de)
English (en)
Inventor
Jan Weikard
Tanja Hebestreit
Frank Richter
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.)
Covestro Intellectual Property GmbH and Co KG
Original Assignee
Covestro Deutschland AG
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 Covestro Deutschland AG filed Critical Covestro Deutschland AG
Priority claimed from PCT/EP2016/078160 external-priority patent/WO2017085268A1/fr
Publication of EP3377235A1 publication Critical patent/EP3377235A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/50—Multilayers
    • B05D7/52—Two layers
    • B05D7/53—Base coat plus clear coat type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
    • B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
    • B05D3/0254—After-treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/50—Multilayers
    • B05D7/52—Two layers
    • B05D7/53—Base coat plus clear coat type
    • B05D7/532—Base coat plus clear coat type the two layers being cured or baked together, i.e. wet on wet
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D1/00—Processes for applying liquids or other fluent materials
    • B05D1/36—Successively applying liquids or other fluent materials, e.g. without intermediate treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D2202/00—Metallic substrate

Definitions

  • the paint When painting high-quality goods such as Automobiles, the paint is usually applied in several layers.
  • a primer is first applied, which should improve the adhesion between the substrate and the subsequent layers depending on the substrate and also serves to protect the substrate from corrosion, if this is susceptible to corrosion.
  • the primer provides for an improvement of the surface texture by covering possibly existing roughness and structure of the substrate.
  • a filler On the primer, especially in metal substrates, often a filler is applied, whose task is the further improvement of the surface texture and the improvement of stone chip susceptibility.
  • On the filler usually one or more color and / or effect layers are applied, which are referred to as basecoat.
  • a high-crosslinked clearcoat is usually applied, which provides the desired glossy appearance and protects the paint system against environmental influences.
  • the basecoat is chemically crosslinked in addition to a physical drying.
  • derivatives of melamine are used as cost-effective crosslinkers. However, these must be cured at temperatures well above 120 ° C together with the clearcoat.
  • WO 2014/009221 and WO 2014/009220 describe polyisocyanate crosslinkers which are said to have improved diffusion into the basecoat. This is accomplished by incorporating hydrophilic groups into the crosslinkers or using certain low viscosity crosslinkers. However, the resulting improved diffusion effect is not strong enough to ensure efficient crosslinking of the basecoat at temperatures below 120 ° C.
  • Another disadvantage of the low molecular weight crosslinker molecules is that they have a low functionality and / or are hydrophilically modified, as a result of which the coating layers crosslinked therewith have poor weathering or chemical resistances.
  • a general way to achieve rapid crosslinking of a low-temperature curing varnish system is to increase the speed of the crosslinking reaction through the use of catalysts.
  • improvements in the crosslinking rate through the use of catalysts unfortunately go hand in hand with an unacceptable deterioration in the appearance of the coating since the crosslinking reaction of the catalyzed coating system already takes place during the course and film formation phase. This provides an irregular surface of the cured lacquer layer.
  • the course of the crosslinking reaction of the catalyzed coating system during the leveling and filming phase can be minimized in part by careful adjustment of the catalyst concentration.
  • this object is achieved by a method for producing a multilayer coating structure, which comprises the following steps: a) providing a substrate, b) applying at least one basecoat film, wherein the basecoat film is substantially free of melamine and its derivatives; c) applying at least one clear and / or topcoat layer comprising at least one polyisocyanate, at least one NCO-reactive compound and at least one thermolatent catalyst; d) Waiting for at least 30 seconds after step c) so that a film can form; e) curing of the multilayer coating structure with heat.
  • the multilayer paint structures produced by the process of the present invention using a thermolatent catalyst exhibit improved interlayer adhesion over the dibutyl tin dilaurate catalyzed systems known in the art.
  • the improved interlayer adhesion appears to be based on the fact that more time is available for the diffusion of the polyisocyanate into the basecoat by the thermolatent catalysis.
  • the inventive method thus allows a good crosslinking of the multilayer coating structure at low temperatures and short Ofenverweil Stammterrorism and can be advantageously used for the application of multilayer coating structures on temperature-sensitive substrates such as thermoplastics or composite materials that are not stable to deformation at elevated temperatures in an industrial manufacturing process become.
  • a further advantage of the method according to the invention is that the painting process, by means of which the significantly lower temperatures used in comparison with the conventional methods, is energy-efficient and inexpensive.
  • the invention furthermore relates to a multilayer paint system obtainable by the process according to the invention, to the use of the multilayer paint system for coating substrates, and to substrates which are coated with this multilayer paint system.
  • multi-layer coating structures are understood to mean those coating structures which comprise at least one basecoat film and at least one clearcoat and / or topcoat film.
  • Basecoat, topcoat and clearcoat can be of the same or different composition in their chemical composition.
  • the basecoat film, topcoat film and clearcoat film are preferably constructed differently in their chemical composition.
  • both the topcoat layer and the clearcoat layer comprise at least one NCO-reactive (isocyanate-reactive) compound.
  • NCO-reactive compound is understood as meaning a compound which can react with polyisocyanates to form polyisocyanate polyaddition compounds, in particular polyurethanes.
  • polyisocyanate compounds are compounds having at least two isocyanate groups per molecule.
  • NCO-reactive compounds it is possible to use all compounds known to the person skilled in the art which have an average OH or NH functionality of at least 1.5. These may be, for example, low molecular weight diols (eg 1,2-ethanediol, 1,3- or 1,2-propanediol, 1,4-butanediol), triols (eg glycerol, trimethylolpropane) and tetraols (eg pentaerythritol), short-term chain polyamines but also polyhydroxy compounds such as polyether polyols, polyester polyols, polyurethane polyols, polysiloxane polyols, polycarbonate polyols, polyether polyamines, polybutadiene polyols, polyacrylate polyols and / or polymethacrylate polyols and their copolymers, hereinafter called polyacrylate polyols.
  • diols eg 1,2-ethan
  • the polyhydroxy compounds preferably have mass-average molecular weights Mw> 500 daltons, measured by gel permeation chromatography (GPC) against a polystyrene standard, more preferably between 800 and 100,000 daltons, in particular between 1,000 and 50,000 daltons.
  • GPC gel permeation chromatography
  • the polyhydroxy compounds preferably have an OH number of 30 to 400 mg KOH / g, in particular between 100 and 300 KOH / g.
  • the hydroxyl number (OH number) indicates how much mg of potassium hydroxide is equivalent to the amount of acetic acid bound by 1 g of substance in the acetylation.
  • the sample is boiled in the determination with acetic anhydride-pyridine and the resulting acid is titrated with potassium hydroxide solution (DIN 53240-2).
  • the glass transition temperatures, measured by means of DSC measurements according to DIN-EN-ISO 1 1357-2, of the polyhydroxy compounds are preferably between -150 and 100 ° C., more preferably between -120 ° C. and 80 ° C.
  • Polyether polyols are accessible in a manner known per se by alkoxylation of suitable starter molecules with base catalysis or use of double metal cyanide compounds (DMC compounds).
  • Suitable starter molecules for the preparation of polyether polyols are, for example, simple, low molecular weight polyols, water, organic polyamines having at least two N-H bonds or any mixtures of such starter molecules.
  • Preferred starter molecules for the preparation of polyether polyols by alkoxylation, in particular by the DMC process are in particular simple polyols such as ethylene glycol, 1,3-propylene glycol and 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 2-ethylhexanediol , 3, glycerol, trimethylolpropane, pentaerythritol and low molecular weight, hydroxyl-containing esters of such polyols with dicarboxylic acids of the type exemplified below or low molecular weight ethoxylation or propoxylation of such simple polyols or any mixtures of such modified or unmodified alcohols.
  • Alkylene oxides which are suitable for the alkoxylation are, in particular, ethylene oxide and / or propylene oxide, which can be used in any order or also in a mixture in the alkoxylation.
  • Polyester polyols are described, for example, in EP-A-0 994 1 17 and EP-A-1 273 640.
  • Polyester polyols can be prepared in a known manner by polycondensation of low molecular weight polycarboxylic acid derivatives, such as, for example, succinic acid, adipic acid, Suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, endomethylenetetra- hydrophthalic anhydride, glutaric anhydride, maleic acid, maleic anhydride, fumaric acid, dimer fatty acid, trimer acid, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, citric acid or trimellitic acid, with low molecular weight polyols, such as ethylene glycol, Diethylene glycol, n
  • polyester polyols such as, for example, lactic acid, cinnamic acid or ⁇ -hydroxycaproic acid can also be polycondensed to form polyester polyols.
  • polyester polyols of oleochemical origin Such polyester polyols, for example, by complete ring opening of epoxidized triglycerides of an at least partially olefinically unsaturated fatty acid-containing fat mixture with one or more alcohols having 1 to 12 carbon atoms and by subsequent partial transesterification of the triglyceride derivatives to alkyl ester polyols having 1 to 12 carbon atoms in Alkyl residue can be produced.
  • Polyurethane polyols are preferably prepared by reacting polyester polyol prepolymers with suitable di- or polyisocyanates and are described, for example, in EP-A-1 273 640.
  • Suitable polysiloxane polyols are described, for example, in WO-A-01/09260, where the polysiloxane polyols cited therein can preferably be used in combination with other polyhydroxy compounds, in particular those having relatively high glass transition temperatures.
  • vinylaromatic hydrocarbons such as vinyltoluene, alpha-methylstyrene or, in particular, styrene, amides or nitriles of acrylic or methacrylic acid, vinyl esters or vinyl ethers, and in minor amounts, in particular, acrylic and / or methacrylic acid.
  • the method according to the invention generally provides for the formation of a film.
  • coagulation and film formation of the clearcoat or topcoat applied to the substrate occur.
  • existing solvent and / or water slowly leaves the film by evaporation.
  • This process can be accelerated by supplying heat or air flow to the surface of the coating. It shrinks the film.
  • the crosslinking reaction of the at least one polyisocyanate with the at least one NCO-reactive compound of the clearcoat or topcoat material begins parallel to the evaporation of the solvent.
  • the heat or catalytically active paint constituents can accelerate the crosslinking reaction.
  • step d) of the process according to the invention is preferably completed after 1 to 5 minutes, particularly preferably after 2 to 3 minutes.
  • step d) wait for at least 30, 45, 60, 120, 180 or 300 seconds, so that a film has been able to form before curing in step e).
  • Pigment paste, black consisting of: 6,20
  • the clearcoat test formulations were calculated so that the polyisocyanate is in excess of 10%.
  • the addition amount of the leveling agent was calculated on the solid resin content.
  • the amount of catalyst was calculated as "ppm of tin based on the solid resin content of the polyisocyanate.”
  • the coating compositions were prepared by mixing the binders with the additives and stirring them at room temperature. Solventnaphta light (1: 1) used. The solvent amounts were chosen so that the theoretical solids content was the same.
  • the basecoat was applied to a PP plate by means of 50 ⁇ ⁇ and incubated for 20 min. dried at 80 ° C in a circulating air paint drying oven. Immediately after cooling (20 min RT), the clearcoat to be tested was then applied by spray application to the basecoat, flashed for 5 minutes at room temperature to allow film formation and then baked for 30 min at 100 ° C in a circulating air paint drying oven.
  • the layer thicknesses of the basecoat and of the clearcoat are identical in all experimental setups (layer thickness basecoat: 12-14 ⁇ m, layer thickness clearcoat: about 40 ⁇ m).
  • the lacquer structure was removed from the PP plate and then the base lacquer on the underside was measured by means of an FT-IR spectrometer (Tensor II with Platinum ATR unit (diamond crystal) from Bruker). Triplicate measurements were carried out.
  • thermolatent catalyst allows for greater migration of isocyanate throughout the basecoat compared to DBTL, as evidenced by the larger peak area / absorbance units measured on the bottom of the basecoat.
  • the clearcoat test formulations were calculated so that the polyisocyanate is equimolar crosslinked with the polyol.
  • the addition amount of the leveling agent was calculated on the solid resin content.
  • the amount of catalyst was calculated as "ppm of tin based on the solid resin content of the polyisocyanate.”
  • the coating compositions were prepared by mixing the binders with the additives and stirring them at room temperature. Methoxypropylacetate-2 / Solventnaphta light (1: 1) used. The amounts of solvent were chosen so that the theoretical solids contents were the same.
  • thermolatent catalyst thermolatent catalyst
  • DBTL dibutyltindilaurate
  • intensity of the NCO peak at wavenumber 2274 cm 4
  • the results (relative change in the intensity of the NCO peaks in%>) are shown in the following table:
  • Pigment paste, black consisting of: 5,50
  • thermolatent catalyst thermolatent catalyst
  • DBTL dibutyltindilaurate
  • thermolatent catalyst thermolatent catalyst
  • DBTL dibutyltindilaurate

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Paints Or Removers (AREA)

Abstract

La présente invention concerne un procédé pour la production d'une structure de laque multicouche, qui présente les étapes suivantes : a) mise à disposition d'un substrat ; b) application d'au moins une couche de laque de base, la couche de laque de base étant essentiellement exempte de mélamine et de ses dérivés ; c) application d'au moins une couche de laque claire et/ou de recouvrement, comprenant au moins un polyisocyanate, au moins un composé réactif avec NCO et au moins un catalyseur thermolatent ; d) attente d'au moins 30 secondes après l'étape c) de telle sorte qu'un film peut se former ; et e) durcissement de la structure de laque multicouche avec apport de chaleur. L'invention concerne également la structure de laque multicouche pouvant être obtenue par le procédé selon l'invention, l'utilisation de la structure de laque multicouche pour le revêtement de substrats ainsi que des substrats revêtus par la structure de laque multicouche.
EP16802006.3A 2015-11-20 2016-11-18 Structure de laque multicouche présentant un catalyseur thermolatent Withdrawn EP3377235A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP2015195521 2015-11-20
PCT/EP2016/078160 WO2017085268A1 (fr) 2015-11-20 2016-11-18 Structure de laque multicouche présentant un catalyseur thermolatent

Publications (1)

Publication Number Publication Date
EP3377235A1 true EP3377235A1 (fr) 2018-09-26

Family

ID=63207391

Family Applications (1)

Application Number Title Priority Date Filing Date
EP16802006.3A Withdrawn EP3377235A1 (fr) 2015-11-20 2016-11-18 Structure de laque multicouche présentant un catalyseur thermolatent

Country Status (1)

Country Link
EP (1) EP3377235A1 (fr)

Similar Documents

Publication Publication Date Title
EP2640779B1 (fr) Agent de revêtement à base de polyuréthane, peintures multicouches à surface mate réalisées à partir de celui-ci et procédé de peinture multicouche
EP1914282B1 (fr) Revêtement aqueux à base d'un mélange de liants comme vernis de base
WO2017182429A1 (fr) Système bi-composant catalysé par catalyseur thermolatent
EP2501496B1 (fr) Agent de revêtement à bonne résistance au stockage, et revêtements ainsi obtenus à haute résistance aux rayures ainsi qu'à bonne résistance aux intempéries
EP2782966B1 (fr) Composition de revêtement de peinture vernie contenant un solvant, procédé de préparation et utilisation de ladite composition
EP2864383A2 (fr) Agent de revêtement présentant une haute résistance aux rayures
WO2017085268A1 (fr) Structure de laque multicouche présentant un catalyseur thermolatent
EP3247731B1 (fr) Système d'agent de revêtement à base de polyols à faible taux d'acidité
EP3247757B1 (fr) Système de revêtement à base de catalyseurs li/bi
EP3334773A1 (fr) Système d'agent de revêtement basé sur des bicatalyseurs et des acides carboxyliques aromatiques
EP3883997B1 (fr) Revêtement dans le moule (imc) auto-demoulable destiné au revêtement de substrats
EP2686359B1 (fr) Compositions d'agents de revêtement à base de polyuréthane, procédés en plusieurs étapes de revêtement impliquant l'utilisation de ces compositions d'agents de revêtement, et utilisation de la composition d'agent de revêtement en tant que vernis transparent et vernis pigmenté, et utilisation du procédé de revêtement pour la mise en peinture en réparation automobile et/ou pour le revêtement de substrats en matière plastique et/ou de véhicules utilitaires
EP2305727A1 (fr) Nouveaux systèmes 2K-PUR
EP2035517A1 (fr) Procédé d'enduisage dans le moule pour la fabrication de pièces moulées, à l'aide d'une préparation de vernis acqueux à deux constituants
WO2019121389A1 (fr) Compositions d'agent de revêtement pour le revêtement de mousses dans un procédé dans le moule
DE102010055780A1 (de) Erosionsschutz-Beschichtungszusammensetzungen
EP3107972B1 (fr) Compositions de produits de revêtement, revêtements ainsi fabriqués et leur utilisation
EP3377235A1 (fr) Structure de laque multicouche présentant un catalyseur thermolatent
EP3083743B1 (fr) Agent adhésif pour vernis transparent sur base solvantée
EP3083081B1 (fr) Agent adhésif pour agents de remplissage sur base solvantée
EP3609960B1 (fr) Agent de revêtement produisant des surfaces structurées
EP2954013B1 (fr) Oligoester alpha,omega-hydroxyfonctionnalisé en tant que promoteur d'adhésion dans des matières de charge à base de solvant
EP4303246A1 (fr) Mélange de polyisocyanates
DE102005024495A1 (de) Wässrige 2-Komponenten-Lackformulierung und deren Verwendung bei der Herstellung von Formteilen

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20180620

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20200206

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: COVESTRO DEUTSCHLAND AG

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: COVESTRO INTELLECTUAL PROPERTY GMBH & CO. KG

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20230302

RIC1 Information provided on ipc code assigned before grant

Ipc: B05D 1/36 20060101ALN20230217BHEP

Ipc: B05D 3/02 20060101ALI20230217BHEP

Ipc: B05D 7/00 20060101AFI20230217BHEP

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20230713