WO2018068837A1 - Impression électrophotographique - Google Patents

Impression électrophotographique Download PDF

Info

Publication number
WO2018068837A1
WO2018068837A1 PCT/EP2016/074367 EP2016074367W WO2018068837A1 WO 2018068837 A1 WO2018068837 A1 WO 2018068837A1 EP 2016074367 W EP2016074367 W EP 2016074367W WO 2018068837 A1 WO2018068837 A1 WO 2018068837A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrophotographic
image
composition
polymer
print substrate
Prior art date
Application number
PCT/EP2016/074367
Other languages
English (en)
Inventor
Tony Azzam
Albert Teishev
Benjamin Dayan
Original Assignee
Hp Indigo B.V.
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 Hp Indigo B.V. filed Critical Hp Indigo B.V.
Priority to PCT/EP2016/074367 priority Critical patent/WO2018068837A1/fr
Publication of WO2018068837A1 publication Critical patent/WO2018068837A1/fr

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/65—Apparatus which relate to the handling of copy material
    • G03G15/6582—Special processing for irreversibly adding or changing the sheet copy material characteristics or its appearance, e.g. stamping, annotation printing, punching
    • G03G15/6585—Special processing for irreversibly adding or changing the sheet copy material characteristics or its appearance, e.g. stamping, annotation printing, punching by using non-standard toners, e.g. transparent toner, gloss adding devices

Definitions

  • An electrophotographic printing process involves creating an image on a photoconductive surface or photo imaging plate (PIP).
  • the image that is formed on the photoconductive surface is a latent electrostatic image having image and background areas with different potentials.
  • an electrophotographic ink composition containing charged toner particles is brought into contact with the selectively charged
  • the charged toner particles adhere to the image areas of the latent image while the background areas remain clean.
  • the image is then transferred to a print substrate (e.g. paper) directly, or by first being transferred to an intermediate transfer member (e.g. a blanket) and then to the print substrate.
  • a print substrate e.g. paper
  • an intermediate transfer member e.g. a blanket
  • Figure 1 is a graph that shows the effect that heating has on the gloss values of unvarnished printed images produced in Example 1 ;
  • Figure 2 is a graph that shows the effect that heating can have on the gloss values of varnished images produced in Example 3.
  • carrier fluid As used in this disclosure, “carrier fluid”, “carrier liquid,” “carrier,” or “carrier vehicle” refers to the fluid in which polymers, particles, charge directors and other additives can be dispersed to form a liquid electrostatic composition or liquid electrophotographic composition.
  • the carrier liquids may include a mixture of a variety of different agents, such as surfactants, co-solvents, viscosity modifiers, and/or other possible ingredients.
  • electrostatic composition generally refers to a composition, which is suitable for use in an
  • the electrophotographic composition may comprise chargeable particles of polymer dispersed in a carrier liquid.
  • the term may refer to an electrophotographic ink composition or an electrophotographic varnish composition.
  • electrophotographic ink composition which may be termed an “electrostatic ink composition” generally refers to an ink composition, which may be in liquid form.
  • the composition is suitable for use in an electrophotographic or electrostatic printing process.
  • the electrophotographic ink composition may include chargeable particles of polymer dispersed in a carrier liquid.
  • the composition may include a colorant that is visible to the eye.
  • electrostatic varnish composition generally refers to a varnish composition, which may be in liquid form and suitable for use in an electrostatic or electrophotographic printing.
  • electrophotographic varnish composition may be applied to an electrophotographically printed image to protect the image and improve, for example, its scratch resistance.
  • the electrophotographic varnish composition may be applied to the entire substrate or to selected areas of the substrate, for example, solely to the printed areas or selected areas of the substrate that include the printed areas.
  • the electrophotographic varnish composition may include chargeable particles of at least one polymer or resin dispersed in a carrier liquid.
  • the electrophotographic varnish composition is transparent and may be substantially devoid of colorant (e.g. dye or pigment).
  • the electrophotographic varnish may be printed electrophotographically over one or more layers of electrophotographically printed ink, for example, in the same print cycle. One or more layers of electrophotographic varnish composition may be applied.
  • the term "transparent" is used to describe a composition that allows light to pass through it.
  • an electrophotographic varnish is used to describe a composition that allows light to pass through it.
  • the term "transparent” may mean that the composition allows light to pass through it such that, when the electrophotographic varnish composition is
  • the electrophotographic varnish composition is transparent, whereby, when the electrophotographic varnish composition is electrographically printed over a printed image of at a thickness of 1 .5 ⁇ , the change in optical density of the varnished image is within +/- 0.05 of the optical density of the un-varnished image.
  • the electrophotographic varnish composition may be transparent, whereby, when the electrophotographic varnish composition is electrophotographically printed over a printed image of at a thickness of 1 .5 ⁇ , the colours in the varnished image are substantially the same as the colours in the unvarnished image. In some examples, the difference in the colour(s) of the varnished and un-varnished image are small. Reference is made to ASTM D1729-96 (Reapproved 2009), which specifies the equipment and procedures for visual appraisal of colours and colour differences of opaque materials that are diffusely illuminated.
  • the delta E (determined according to CIE94) between the colours of the varnished and un-varnished image may be 3 or less, for example, 2 or less. In some examples, the delta E (determined according to CIE94) may be 1.5 or less, for example, 1 or less.
  • Optical density as mentioned above is a quantitative measure expressed as a logarithmic ratio between the radiation falling upon a material and the radiation transmitted through a material.
  • ⁇ A is the absorbance at a certain wavelength of light (A)
  • ⁇ l is the intensity of the radiation (light) that has passed through the material (transmitted radiation)
  • ⁇ is the intensity of the radiation before it passes through the material (incident radiation).
  • the incident radiation may be any suitable white light, for example, day light or artificial white light.
  • the optical density or delta E of an image may be determined using methods that are well-known in the art. For example, optical density and/or delta E may be determined using a spectrophotometer. Suitable spectrophotometers are available under the trademark X-rite.
  • colorant generally includes pigments or dyes that are visible by eye.
  • co-polymer refers to a polymer that is polymerized from at least two monomers.
  • terpolymer refers to a polymer that is polymerized from 3 monomers.
  • melt index and “melt flow rate” are used
  • melt index refers to the extrusion rate of a resin through an orifice of defined dimensions at a specified temperature and load, reported as temperature/load, e.g. 190°C/2.16 kg.
  • melt flow rate or “melt index” is measured per ASTM D1238-04c Standard Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer. If a melt flow rate of a particular polymer is specified, unless otherwise stated, it is the melt flow rate for that polymer alone, in the absence of any of the other components of the electrostatic composition.
  • acidity refers to the mass of potassium hydroxide (KOH) in milligrams that neutralizes one gram of a substance.
  • KOH potassium hydroxide
  • the acidity of a polymer can be measured according to standard techniques, for example as described in ASTM D1386. If the acidity of a particular polymer is specified, unless otherwise stated, it is the acidity for that polymer alone, in the absence of any of the other components of the liquid toner composition.
  • melt viscosity generally refers to the ratio of shear stress to shear rate at a given shear stress or shear rate. Testing may be performed using a capillary rheometer. A plastic charge is heated in the rheometer barrel and is forced through a die with a plunger. The plunger is pushed either by a constant force or at constant rate depending on the equipment. Measurements are taken once the system has reached steady-state operation. One method used is measuring Brookfield viscosity @ 140°C, units are mPa-s or cPoise, as known in the art. Alternatively, the melt viscosity can be measured using a rheometer, e.g.
  • melt viscosity of a particular polymer is specified, unless otherwise stated, it is the melt viscosity for that polymer alone, in the absence of any of the other components of the electrostatic composition.
  • a polymer may be described as comprising a certain weight percentage of monomer. This weight percentage is indicative of the repeating units formed from that monomer in the polymer.
  • electrophotographic printing or “electrophotographic printing” refers to the process that provides an image that is transferred from a photo imaging plate either directly or indirectly via an intermediate transfer member to a print substrate. As such, the image may not be substantially absorbed into the photo imaging substrate on which it is applied.
  • electrophotographic printers or “electrostatic printers” refer to those printers capable of performing electrophotographic printing or electrostatic printing, as described above.
  • An electrophotographic printing process may involve subjecting the electrophotographic composition to an electric field, e.g. an electric field having a field gradient of 1-400 ⁇ / ⁇ " ⁇ , or more, in some examples 600-900 ⁇ / ⁇ " ⁇ , or more.
  • substituted may indicate that a hydrogen atom of a compound or moiety is replaced by another atom such as a carbon atom or a heteroatom, which is part of a group referred to as a substituent.
  • substituents include, for example, alkyl, alkoxy, aryl, aryloxy, alkenyl, alkenoxy, alkynyl, alkynoxy, thioalkyl, thioalkenyl, thioalkynyl, thioaryl, etc.
  • heteroatom may refer to nitrogen, oxygen, halogens, phosphorus, or sulfur.
  • alkyl or similar expressions such as “alk” in alkaryl, may refer to a branched, unbranched, or cyclic saturated hydrocarbon group, which may, in some examples, contain from 1 to about 50 carbon atoms, or 1 to about 40 carbon atoms, or 1 to about 30 carbon atoms, or 1 to about 10 carbon atoms, or 1 to about 5 carbon atoms, for example.
  • aryl may refer to a group containing a single aromatic ring or multiple aromatic rings that are fused together, directly linked, or indirectly linked (such that the different aromatic rings are bound to a common group such as a methylene or ethylene moiety).
  • Aryl groups described in this disclosure may contain, but are not limited to, from 5 to about 50 carbon atoms, or 5 to about 40 carbon atoms, or 5 to 30 carbon atoms or more, and may be selected from, phenyl and naphthyl.
  • acrylic and acrylate refer to any acrylic or acrylate compound.
  • acrylic includes acrylic and methacrylic compounds unless the context dictates otherwise.
  • the term “acrylic” includes acrylic and methacrylic compounds unless the context dictates otherwise.
  • acrylate includes acrylate and methacrylate compounds unless the context dictates otherwise.
  • the term "about” is used to provide flexibility to a numerical range endpoint by providing that a given value may be a little above or a little below the endpoint to allow for variation in test methods or apparatus.
  • the degree of flexibility of this term can be dictated by the particular variable and would be within the knowledge of those skilled in the art to determine based on experience and the associated description in this disclosure.
  • weight% (wt%) values are to be taken as referring to a weight-for-weight (w/w) percentage of solids in the composition, and not including the weight of any carrier fluid present.
  • the present disclosure relates to a printing method comprising
  • electrophotographic varnish composition is electrophotographically printed over the printed image to form a varnished image.
  • the varnished image on the print substrate is heated to a temperature of at least 120 degrees C. In one example, the varnished image on the print substrate is heated to a temperature of at least 130 degrees C.
  • Some electrophotographically printed images do not have the desired degree of gloss.
  • the gloss of an image can be improved by laminating a polymer film over the printed image. Heat and pressure can be applied over the film to produce a laminated substrate.
  • the laminated polymer film can provide the printed substrate with a desired level of gloss.
  • an electrophotographic varnish may be used to improve the gloss of a printed image.
  • a varnished image can be produced.
  • the varnish can improve the scratch resistance of the image.
  • this heating may cause at least part (e.g. the polymer component) of the varnish to melt and flow over the surface of the print substrate. This can produce a smoother surface over the image formed by the electrophotographic ink, enhancing the gloss of the image without, for example, the need for a laminated film.
  • gloss can be enhanced on selected areas of the print substrate, for example, only on areas that bear images formed of electrophotographically printed ink.
  • the electrophotographic varnish may be printed over ink-bearing areas and non-ink-bearing areas, such that e.g. the entire print substrate has a gloss appearance.
  • the print substrate bearing the varnished image is heated while the varnish is exposed.
  • the varnish may form the uppermost layer on the print substrate.
  • the heating step may be performed on the print substrate when the varnish forms the uppermost layer. This can allow the varnish to melt and flow to form a smooth outermost surface on the printed substrate, thereby improving its gloss.
  • lamination of the printed substrate with a polymer film may not be necessary once the varnished image on the printed substrate has been heated to improve its gloss.
  • a polymer film may be applied, for example, to improve the gloss of the image further.
  • the varnished image on the print substrate is heated to a temperature of at least 120 degrees C, for example, at least 130 degrees C.
  • the varnished image on the print substrate may be heated to a temperature of at most 160 degrees C, for example, at most 140 degrees C.
  • the varnished image on the print substrate may be heated to a temperature of 120 to 160 degrees C or 125 to 135 degrees C.
  • the varnished image on the print substrate may be heated to a temperature of about 130 degrees C.
  • the electrophotographic varnish composition comprises at least one polymer resin having a melting point of less than 1 10 degrees C, for example, less than 100 degrees C.
  • the substrate bearing the varnished image is heated to a temperature of at least 120 degrees.
  • the temperature and duration of this heating step may be controlled to cause polymer resin in the varnish to melt or soften.
  • the polymer resin may flow over the print substrate and form a smoother or more level surface over the print substrate. This may provide a varnished image with enhanced gloss.
  • the substrate bearing the varnished image may then be left to cool.
  • heating may be carried out using any suitable heating method.
  • the varnished substrate may be heated in an oven or by exposure to radiation, for example, infrared, near infrared or e-beam radiation to heat the varnish composition on the print substrate to at least 120 degrees C.
  • the electrophotographic ink composition As mentioned above, the electrophotographic ink composition and
  • electrophotographic varnish composition used in the present disclosure are
  • electrophotographic compositions may comprise a polymer or a combination of polymers. These electrophotographic compositions may be liquid electrophotographic compositions.
  • the electrophotographic compositions may also comprise at least one of a charge adjuvant, a charge director and a carrier liquid.
  • the electrophotographic compositions comprise a polymer, a charge adjuvant and a liquid carrier.
  • the electrophotographic compositions comprise a polymer, a charge adjuvant, a charge director and a liquid carrier.
  • the electrophotographic composition may additionally include a colorant.
  • the colorant may have a colour that is visible to the naked eye.
  • the electrophotographic varnish composition is transparent and may be substantially devoid of colorant.
  • the electrophotographic varnish composition may include a wax.
  • the electrophotographic composition e.g. the electrophotographic composition
  • electrophotographic ink composition or electrophotographic varnish composition may include a polymer.
  • a suitable polymer is an olefin polymer resin having acid and/or ester side groups.
  • the acid groups may be derived from an acrylic acid (e.g. acrylic acid or methacrylic acid).
  • the ester groups may be derived from an acrylate (e.g. acrylate or methacrylate).
  • the polymer is a polymer of an olefin (e.g. ethylene) and an acrylic acid (e.g. acrylic acid or methacrylic acid) or acrylate (e.g. acrylate or methacrylate).
  • the polymer may have a melting point of less than 1 10 degrees C or less than 100 degrees C. In one example, the polymer may have a melting point of 50 to up to 1 10 degrees C, for example, 60 to 100 degrees C. Where a polymer mixture is present, the polymer mixture may have a melting point of less than 1 10 degrees C or less than 100 degrees C. In one example, the polymer mixture may have a melting point of 50 to up to 1 10 degrees C, for example, 60 to 100 degrees C. Such polymers or polymer mixtures may be present in the electrophotographic varnish composition. Accordingly, when the electrophotographic varnish composition on the print substrate is heated to at least 120 degrees C, the polymer(s) or polymer mixture may melt and flow over the print substrate to form a more level varnish layer, thereby increasing the gloss of the varnished image.
  • the polymer is a polymer of an olefin (e.g. ethylene) and an acrylic acid (e.g. acrylic acid or methacrylic acid) or acrylate (e.g. acrylate or methacrylate) having a melting point of less than 1 10 degrees C or less than 100 degrees C.
  • the polymer is a polymer of an olefin (e.g. ethylene) and an acrylic acid (e.g. acrylic acid or methacrylic acid) or acrylate (e.g. acrylate or methacrylate) having a melting point of 50 to up to 1 10 degrees C, for example, 60 to 100 degrees C or 70 to 95 degrees C.
  • the electrophotographic composition comprises a mixture of two or more polymers
  • at least 50 weight %, at least 60 weight %, at least 70 weight %, at least 80 weight % or at least 90 weight % of the polymer mixture may be formed of polymer(s) having melting points of less than 1 10 degrees C or less than 100 degrees C.
  • at least 50 weight % at least 60 weight %, at least 70 weight %, at least 80 weight % or at least 90 weight % of the polymer mixture may be formed of polymer(s) having melting points of 50 to up to 1 10 degrees C, for example, 60 to 100 degrees C.
  • polymer is a polymer of an olefin (e.g. ethylene) and at least one monomer selected from an acrylic or acrylate monomer, for instance, methacrylic acid, acrylic acid, acrylate and methacrylate.
  • the polymer may comprise at least 80 weight % olefin (e.g. ethylene), for example, 80 to 90 weight% olefin (e.g. ethylene).
  • the polymer may include 10 to 20 weight % of an acrylic or acrylate monomer, for example, at least one of methacrylic acid, acrylic acid, acrylate and methacrylate.
  • the polymer is a polymer of an olefin (e.g. ethylene) and methacrylic acid.
  • the polymer may include 80 to 90 weight % ethylene and 10 to 20 weight % methacrylic acid.
  • the polymer may include 85 weight % ethylene and the remainder methacrylic acid.
  • the polymer is or comprises a polymer sold under the trademark Nucrel ® 925.
  • the polymer is a polymer of an olefin (e.g. ethylene) and acrylic acid.
  • the polymer may include 80 to 90 weight % ethylene and 10 to 20 weight % acrylic acid.
  • the polymer includes 82 weight % ethylene and the remainder acrylic acid.
  • the polymer is or comprises a polymer sold under the trademark Nucrel ® 2806.
  • the polymer resin may include more than one polymer.
  • the polymer resin may include 2 or 3 polymers.
  • the polymer comprises a polymer of an olefin (e.g. ethylene) and acrylic acid and a polymer of an olefin (e.g. ethylene) and methacrylic acid.
  • the polymer resin may include a first resin formed of 80 to 90 weight % ethylene and 10 to 20 weight % methacrylic acid, and a second resin formed of 80 to 90 weight % ethylene and 10 to 20 weight % acrylic acid.
  • the amount of the first resin may be 60 to 80 weight %, for example, 65 to 75 weight % of the polymer resin mixture.
  • the amount of second resin may be 15 to 25 weight %, for example, 17 to 22 weight % of the polymer resin mixture.
  • the weight ratio the first resin to the second resin may be 2:1 to 5:1 , for example, 3:1 to 4:
  • the polymer resin includes a first resin formed of 85 weight % ethylene and the remainder methacrylic acid, and a second resin formed of 82 weight % ethylene and the remainder acrylic acid.
  • the polymer resin includes a mixture of a polymer sold under the trademark Nucrel ®925 and a polymer sold under the trademark Nucrel®2806.
  • the polymer may also include a terpolymer.
  • the terpolymer may be a terpolymer of a) an olefin (e.g. ethylene), b) an acrylic acid (e.g. acrylic acid or methacrylic acid) or an acrylate (e.g. acrylate or methacrylate) and c) a polar monomer.
  • the olefin (e.g. ethylene) may form 60 to 78 weight % of the terpolymer, for example, 65 to 70 weight % of the terpolymer.
  • the acrylic acid e.g. acrylic acid or methacrylic acid
  • acrylate e.g. acrylate or methyl acrylate
  • the polar monomer may form the remainder of the terpolymer.
  • suitable polar monomers include monomers containing amine, amide, ester, ether and/or anhydride functional groups.
  • the polar monomer contains amide, amine, groups, anhydride groups or both ester and ether groups.
  • the polar monomer is selected from maleic anhydride or glycidyl methacrylate.
  • the terpolymer is a terpolymer of ethylene, methacrylic acid and glycidyl methacrylate.
  • the amount of ethylene may be 60 to 78 weight % of the polymer, for example, 65 to 70 weight % of the terpolymer.
  • the amount of methacrylic acid may range from 20 to 35 weight % of the terpolymer, for example, 22 to 30 weight % of the terpolymer.
  • the remainder of the polymer may be derived from glycidyl methacrylate.
  • the terpolymer comprises 68 weight % ethylene, 24 weight % methacrylic acid and 8 weight % glycidyl methacrylate.
  • the terpolymer may be one sold under the trademark Lotader ® AX8900.
  • the terpolymer may be used in combination with a copolymer of ethylene and methacrylic acid or acrylic acid.
  • such terpolymers for instance one sold under the trademark Lotader® AX8900
  • the terpolymer is a terpolymer of ethylene, ethyl acrylate and maleic anhydride.
  • the amount of ethylene may be 60 to 80 weight % of the terpolymer, for example, 65 to 70 weight % of the terpolymer.
  • the amount of ethyl acrylate may range from 19 to 35 weight % of the terpolymer, for example, 20 to 30 weight % of the
  • the remainder of the terpolymer may be derived from maleic anhydride.
  • the amount of maleic anhydride may be 0.1 to 5 weight %, for example, 1 to 3 weight %.
  • the terpolymer comprises 70 weight % ethylene, 29 weight % ethyl acrylate and 1 .3 weight % maleic anhydride.
  • the terpolymer may be used in combination with a copolymer of ethylene and methacrylic acid or acrylic acid.
  • the terpolymer may be sold under the trademark Lotader ® 4700.
  • the polymer B may be one or more polymers sold under the trademark Lotader ® 5500, Lotader ® 4503 and Lotader ® 4720.
  • Such terpolymers for instance one sold under the trademark Lotader ® 4700
  • the terpolymer may form 1 to 50 weight % of the polymer resin. In some examples, the terpolymer forms 1 to 20 weight %, for instance 5 to 15 weight % of the polymer resin.
  • a copolymer of an olefin (e.g.) and an acrylic or acrylate (e.g. methacrylic acid, acrylic acid, methacrylate or acrylate) is employed, the copolymer may form 50 to100 weight %, for example, 70 to 99 weight %, for instance, 80 or 85 to 95 weight % of the polymer resin.
  • the polymer resin in the electrophotographic composition may have a melting point of less than 1 10 degrees C, for example, less than 100 degrees C.
  • the polymer may melt when the varnished image is heated to a temperature of at least 120 degrees C.
  • the polymer in the varnish melts and flows, it can form a smooth layer over the surface of the printed substrate, improving its gloss.
  • the presence of colorants in the ink may impede the flow of the resin.
  • the polymer resin may have (or may contain a polymer having) an acidity of 50 mg KOH/g or more, in some examples an acidity of 60 mg KOH/g or more, in some examples an acidity of 70 mg KOH/g or more, in some examples an acidity of 80 mg KOH/g or more, in some examples an acidity of 90 mg KOH/g or more, in some examples an acidity of 100 mg KOH/g or more, in some examples an acidity of 105 mg KOH/g or more, in some examples 1 10 mg KOH/g or more, in some examples 1 15 mg KOH/g or more.
  • the polymer may have an acidity of 200 mg KOH/g or less, in some examples 190 mg or less, in some examples 180 mg or less, in some examples 130 mg KOH/g or less, in some examples 120 mg KOH/g or less. Acidity of a polymer, as measured in mg KOH/g can be measured using standard procedures known in the art, for example using the procedure described in ASTM D1386.
  • the resin may comprise a polymer that has a melt flow rate of less than about 70 g/10 minutes, in some examples about 60 g/10 minutes or less, in some examples about 50 g/10 minutes or less, in some examples about 40 g/10 minutes or less, in some examples 30 g/10 minutes or less, in some examples 20 g/10 minutes or less, in some examples 10 g/10 minutes or less.
  • all polymers each individually have a melt flow rate of less than 90 g/10 minutes, 80 g/10 minutes or less, in some examples 80 g/10 minutes or less, in some examples 70 g/10 minutes or less, in some examples 70 g/10 minutes or less, in some examples 60 g/10 minutes or less.
  • the resin may comprise a polymer having a melt flow rate of about 10 g/10 minutes to about 120 g/10 minutes, in some examples about 10 g/10 minutes to about 70 g/10 minutes, in some examples about 10 g/10 minutes to 40 g/10 minutes, in some examples 20 g/10 minutes to 30 g/10 minutes.
  • the polymer having acidic side groups can have a melt flow rate of, in some examples, about 50 g/10 minutes to about 120 g/10 minutes, in some examples 60 g/10 minutes to about 100 g/10 minutes.
  • the melt flow rate can be measured using standard procedures known in the art, for example as described in ASTM D1238.
  • a terpolymer may have a melt index of 1 to 20 g/10min, for instance, 1 to 9g/10 or 10g/1 Omin.
  • the terpolymer has a melt index of 3 to 8g/10min, for instance, 4 to 7g/10min.
  • the copolymer may have a melt index of 20 to 200g/10min, for example, 25 to 70g/10min. In one example, the copolymer has a melt index of 25 to 35 g/1 Omin.
  • This copolymer may be used in combination with another copolymer of an olefin (e.g.) and an acrylic or acrylate (e.g. methacrylic acid, acrylic acid, methacrylate or acrylate) having a melt index of 50 to 70 g/1 Omin.
  • the acidic side groups may be in free acid form or may be in the form of an anion and associated with one or more counterions, typically metal counterions, e.g. a metal selected from the alkali metals, such as lithium, sodium and potassium, alkali earth metals, such as magnesium or calcium, and transition metals, such as zinc.
  • the polymer having acidic sides groups can be selected from resins such as co-polymers of ethylene and an ethylenically unsaturated acid of either acrylic acid or methacrylic acid; and ionomers thereof, such as methacrylic acid and ethylene-acrylic or methacrylic acid co-polymers which are at least partially neutralized with metal ions (e.g.
  • the polymer comprising acidic side groups can be a co-polymer of ethylene and an ethylenically unsaturated acid of either acrylic or methacrylic acid, where the ethylenically unsaturated acid of either acrylic or methacrylic acid constitute from 5 wt% to about 25 wt% of the co-polymer, in some examples from 10 wt% to about 20 wt% of the co-polymer.
  • the resin may comprise two different polymers having acidic side groups.
  • the two polymers having acidic side groups may have different acidities, which may fall within the ranges mentioned above.
  • the resin may comprise a first polymer having acidic side groups that has an acidity of from 10 mg KOH/g to 1 10 mg KOH/g, in some examples 20 mg KOH/g to 1 10 mg KOH/g, in some examples 30 mg KOH/g to 1 10 mg KOH/g, in some examples 50 mg KOH/g to 1 10 mg KOH/g, and a second polymer having acidic side groups that has an acidity of 1 10 mg KOH/g to 130 mg KOH/g.
  • the resin may comprise two different polymers having acidic side groups: a first polymer having acidic side groups that has a melt flow rate of about 10 g/10 minutes to about 50 g/10 minutes and an acidity of from 10 mg KOH/g to 1 10 mg KOH/g, in some examples 20 mg KOH/g to 1 10 mg KOH/g, in some examples 30 mg KOH/g to 1 10 mg KOH/g, in some examples 50 mg KOH/g to 1 10 mg KOH/g, and a second polymer having acidic side groups that has a melt flow rate of about 50 g/10 minutes to about 120 g/10 minutes and an acidity of 1 10 mg KOH/g to 130 mg KOH/g.
  • the first and second polymers may be absent of ester groups.
  • the ratio of the first polymer having acidic side groups to the second polymer having acidic side groups can be from about 10:1 to about 2:1.
  • the ratio can be from about 6:1 to about 3:1 , in some examples about 4:1.
  • the resin may comprise a polymer having a melt viscosity of 15000 poise or less, in some examples a melt viscosity of 10000 poise or less, in some examples 1000 poise or less, in some examples 100 poise or less, in some examples 50 poise or less, in some examples 10 poise or less; said polymer may be a polymer having acidic side groups as described in this disclosure.
  • the resin may comprise a first polymer having a melt viscosity of 15000 poise or more, in some examples 20000 poise or more, in some examples 50000 poise or more, in some examples 70000 poise or more; and in some examples, the resin may comprise a second polymer having a melt viscosity less than the first polymer, in some examples a melt viscosity of 15000 poise or less, in some examples a melt viscosity of 10000 poise or less, in some examples 1000 poise or less, in some examples 100 poise or less, in some examples 50 poise or less, in some examples 10 poise or less.
  • the resin may comprise a first polymer having a melt viscosity of more than 60000 poise, in some examples from 60000 poise to 100000 poise, in some examples from 65000 poise to 85000 poise; a second polymer having a melt viscosity of from 15000 poise to 40000 poise, in some examples 20000 poise to 30000 poise, and a third polymer having a melt viscosity of 15000 poise or less, in some examples a melt viscosity of 10000 poise or less, in some examples 1000 poise or less, in some examples 100 poise or less, in some examples 50 poise or less, in some examples 10 poise or less.
  • the melt viscosity can be measured using a rheometer, e.g. a commercially available AR-2000 Rheometer from Thermal Analysis Instruments, using the geometry of: 25mm steel plate-standard steel parallel plate, and finding the plate over plate rheometry isotherm at 120°C, 0.01 hz shear rate.
  • the polymer (excluding any other components of the electrostatic composition) may have a melt viscosity of 6000 poise or more, in some examples a melt viscosity of 8000 poise or more, in some examples a melt viscosity of 10000 poise or more, in some examples a melt viscosity of 12000 poise or more.
  • the resin comprises a plurality of polymers
  • all the polymers of the resin may together form a mixture (excluding any other components of the electrostatic composition) that has a melt viscosity of 6000 poise or more, in some examples a melt viscosity of 8000 poise or more, in some examples a melt viscosity of 10000 poise or more, in some examples a melt viscosity of 12000 poise or more.
  • Melt viscosity can be measured using standard techniques. The melt viscosity can be measured using a rheometer, e.g. a commercially available AR-2000 Rheometer from Thermal Analysis Instruments, using the geometry of: 25mm steel plate-standard steel parallel plate, and finding the plate over plate rheometry isotherm at 120°C, 0.01 Hz shear rate.
  • the resin can constitute about 5 to up to 100 weight %, in some examples about 50 to 99 %, by weight of the solids of the liquid electrophotographic composition.
  • the resin can constitute about 60 to 95 %, in some examples about 70 to 95 %, by weight of the solids of the liquid electrophotographic composition.
  • the polymer or polymer mixture used in the electrophotographic ink composition may be the same or different to the polymer or polymer mixture used in the electrophotographic varnish composition.
  • the electrophotographic composition e.g., the electrophotographic composition
  • electrophotographic ink composition or electrophotographic varnish composition can include a charge adjuvant.
  • a charge adjuvant may be present with a charge director, and may be different to the charge director, and act to increase and/or stabilise the charge on particles, e.g. resin-containing particles, of an electrostatic composition.
  • the charge adjuvant can include, but is not limited to, barium petronate, calcium petronate, Co salts of naphthenic acid, Ca salts of naphthenic acid, Cu salts of naphthenic acid, Mn salts of naphthenic acid, Ni salts of naphthenic acid, Zn salts of naphthenic acid, Fe salts of naphthenic acid, Ba salts of stearic acid, Co salts of stearic acid, Pb salts of stearic acid, Zn salts of stearic acid, Al salts of stearic acid, Cu salts of stearic acid, Fe salts of stearic acid, metal carboxylates (e.g.
  • acrylamidoglycolate alkyl ether e.g. methyl acrylamidoglycolate methyl ether-co-vinyl acetate
  • hydroxy bis(3,5-di-tert- butyl salicylic) aluminate monohydrate e.g. methyl acrylamidoglycolate methyl ether-co-vinyl acetate
  • the charge adjuvant is aluminium di and/or tristearate and/or aluminium di and/or tripalmitate.
  • the charge adjuvant can constitute about 0.1 to 5 % by weight of the solids of the liquid electrophotographic composition.
  • the charge adjuvant can constitute about 0.5 to 4 % by weight of the solids of the liquid electrophotographic composition.
  • the charge adjuvant can constitute about 1 to 3 % by weight of the solids of the liquid
  • the charge adjuvant used in the electrophotographic ink composition may be the same or different to the charge adjuvant used in the electrophotographic varnish composition.
  • a charge director may be added to the electrophotographic composition (e.g. electrophotographic ink composition or electrophotographic varnish composition).
  • the charge director comprises nanoparticles of a simple salt and a salt of the general formula MA n , wherein M is a barium, n is 2, and A is an ion of the general formula [Ri-0-C(0)CH 2 CH(S0 3 " )C(0)-0-R2], where each of Ri and R 2 is an alkyl group e.g. as discussed above.
  • the sulfosuccinate salt of the general formula MA n is an example of a micelle forming salt.
  • the charge director may be substantially free or free of an acid of the general formula HA, where A is as described above.
  • the charge director may comprise micelles of said sulfosuccinate salt enclosing at least some of the nanoparticles.
  • the charge director may comprise at least some nanoparticles having a size of 10 nm or less, in some examples 2 nm or more (e.g. 4 - 6 nm).
  • the simple salt may comprise a cation selected from Mg , Ca , Ba , NH 4 , tert- butyl ammonium, Li + , and ⁇ 3 , or from any sub-group thereof.
  • the simple salt is an inorganic salt, for instance, a barium salt.
  • the simple salt may comprise an anion selected from S0 4 2" , PO 3" , N0 3 " , HP0 4 2" , C0 3 2" , acetate, trifluoroacetate (TFA), CI “ , Bf, F " , CI0 4 " , and Ti0 3 4" , or from any sub-group thereof.
  • the simple salt comprises a hydrogen phosphate anion.
  • the simple salt may be selected from CaCOs, Ba 2 Ti0 3 , AI 2 (S0 4 ) 3 , AI(N0 3 ) 3 , Ca 3 (P0 4 ) 2 , BaS0 4 , BaHP0 4 , Ba 2 (P0 4 ) 3 , CaS0 4 , (NH 4 ) 2 C0 3 , (NH 4 ) 2 S0 4 , NH 4 OAc, Tert- butyl ammonium bromide, NH 4 N0 3 , LiTFA, AI 2 (S0 4 ) 3 , LiCI0 4 and LiBF 4 , or any sub-group thereof.
  • the simple salt may be BaHP0 4 .
  • each of Ri and R 2 is an aliphatic alkyl group.
  • each of Ri and R 2 independently is a Ce-25 alkyl.
  • said aliphatic alkyl group is linear.
  • said aliphatic alkyl group is branched.
  • said aliphatic alkyl group includes a linear chain of more than 6 carbon atoms.
  • Ri and R 2 are the same.
  • at least one of Ri and R 2 is Ci 3 H 27 .
  • the charge director can constitute about 0.001 % to 20%, in some examples 0.01 to 20% by weight, in some examples 0.01 to 10% by weight, in some examples 0.01 to 1 % by weight of the solids of the electrostatic composition.
  • the charge director can constitute about 0.001 to 0.15 % by weight of the solids of the liquid electrophotographic composition, in some examples 0.001 to 0.15 %, in some examples 0.001 to 0.02 % by weight of the solids of the liquid electrophotographic composition.
  • the charge director imparts a negative charge on the electrostatic composition.
  • the particle conductivity may range from 50 to 500 pmho/cm, in some examples from 200-350 pmho/cm.
  • the charge director used in the electrophotographic ink composition may be the same or different to the charge director used in the electrophotographic ink composition
  • the electrophotographic composition (e.g. electrophotographic ink composition or electrophotographic varnish composition) may be printed in liquid form.
  • the carrier liquid for the liquid electrophotographic composition can act as a dispersing medium for the other components in the electrostatic composition.
  • the carrier liquid can comprise or be a hydrocarbon, silicone oil, vegetable oil, etc.
  • the carrier liquid can include, but is not limited to, an insulating, non-polar, non-aqueous liquid that can be used as a medium for toner particles.
  • the carrier liquid can include compounds that have a resistivity in excess of about 10 9 ohm-cm.
  • the carrier liquid may have a dielectric constant below about 5, in some examples below about 3.
  • the carrier liquid can include, but is not limited to, hydrocarbons.
  • the hydrocarbon can include, but is not limited to, an aliphatic hydrocarbon, an isomerized aliphatic hydrocarbon, branched chain aliphatic hydrocarbons, aromatic hydrocarbons, and combinations thereof.
  • the carrier liquids include, but are not limited to, aliphatic hydrocarbons, isoparaffinic compounds, paraffinic compounds, dearomatized hydrocarbon compounds, and the like. In some examples, the carrier liquid is an isoparaffinic liquid.
  • the carrier liquids can include, but are not limited to liquids sold under the trademarks, Isopar-GTM, Isopar-HTM, Isopar-LTM, Isopar-MTM, Isopar-KTM, Isopar-VTM, Norpar 12TM, Norpar 13TM, Norpar 15TM, Exxol D40TM, Exxol D80TM, Exxol D100TM, Exxol D130TM, and Exxol D140TM (each sold by EXXON CORPORATION); Teclen N-16TM, Teclen N-20TM, Teclen N-22TM, Nisseki
  • the carrier liquid Before printing, the carrier liquid can constitute about 20% to 99.5% by weight of the electrostatic composition, in some examples 50% to 99.5% by weight of the electrostatic composition. Before printing, the carrier liquid may constitute about 40 to 90 % by weight of the electrostatic composition. Before printing, the carrier liquid may constitute about 60% to 80% by weight of the electrostatic composition. Before printing, the carrier liquid may constitute about 90% to 99.5% by weight of the electrostatic composition, in some examples 95% to 99% by weight of the electrostatic composition.
  • the composition when printed on the print substrate may be substantially free from carrier liquid.
  • the carrier liquid may be removed, e.g. by an electrophoresis processes during printing and/or evaporation, such that substantially just solids are transferred to the print substrate.
  • Substantially free from carrier liquid may indicate that the ink or varnish printed on the print substrate contains less than 5 wt% carrier liquid, in some examples, less than 2 wt% carrier liquid, in some examples less than 1 wt% carrier liquid, in some examples less than 0.5 wt% carrier liquid.
  • the ink or varnish printed on the print substrate is free from carrier liquid.
  • liquid carrier or liquid carrier mixture used in the electrophotographic ink composition may be the same or different to the liquid carrier or liquid carrier mixture used in the electrophotographic varnish composition.
  • the electrophotographic ink composition may include a colorant.
  • the colorant may be selected from a pigment, dye and a combination thereof.
  • the colorant may be unicolor or composed of any combination of available colours.
  • the electrophotographic ink composition includes at least one colorant selected from a cyan colorant, a yellow colorant, a magenta colorant and a black colorant.
  • the ink may be a yellow, cyan, magenta or black ink.
  • the electrophotographic ink composition may include a plurality of colorants.
  • the electrophotographic ink composition may include a first colorant and second colorant, which are different from one another.
  • the colorant may be selected from a phthalocyanine colorant, an indigold colorant, an indanthrone colorant, a monoazo colorant, a diazo colorant, inorganic salts and
  • the colorant may be present in an amount of 0.1 to 10 weight %, for instance, 2 to 5 weight % of the total weight of solids of the composition.
  • the electrophotographic varnish composition may contain less than 0.05 weight %, for example, less than 0.01 weight % of colorant.
  • the electrophotographic varnish composition may be devoid of colorant.
  • the electrophotographic varnish composition may be devoid of cyan, yellow, magenta or black colorant.
  • the presence of colorant in the electrophotographic ink may impede the flow of polymer in the electrophotographic ink, for example, even when the print substrate bearing a varnished image is heated to a temperature of at least 120 degrees C (e.g. at least 130 degrees C).
  • the electrophotographic varnish composition may include a wax.
  • the wax may be a synthetic wax. Suitable waxes include paraffin waxes. Wax may improve the peel resistance of the varnished image.
  • the wax may be present in an amount of 1 to 10 weight %, for example, 3 to 7 weight % of solids in the electrophotographic varnish composition.
  • the wax may comprise at least 12 carbon atoms, for instance, at least 15 carbon atoms.
  • the wax may comprise 16 to 60 carbon atoms, for example, 18 to 50 carbon atoms or 20 to 40 carbon atoms.
  • the wax may comprise at least one paraffinic or hydrocarbyl (e.g. alkyl) group having at least 12 carbon atoms, for example, at least 16 carbon atoms.
  • the wax may comprise at least one hydrocarbyl (e.g. alkyl) group having 12 to 22 carbon atoms, for example, 16 to 20 carbon atoms.
  • the wax may comprise at least one (e.g. 2) Cis alkyl groups.
  • the paraffin wax may be functionalised.
  • the wax comprises an amide group.
  • the wax is an amide of a fatty acid.
  • the wax is a reaction product of a diamine and a fatty acid.
  • the wax may be a reaction product of an olefin diamine and a fatty acid.
  • An example of a suitable olefin is ethylene diamine.
  • Suitable fatty acids include fatty acids having 10 to 30 carbon atoms, for example, 15 to 25 or 16 to 20 carbon atoms.
  • An example of a suitable fatty acid is stearic acid.
  • the wax may be ethylene bis(stearamide).
  • a suitable wax may be sold under the trademark
  • the wax may be dispersed in a matrix of the polymer present in the
  • the wax may form "islands" in a sea of polymer(s).
  • the electrophotographic composition may comprise composite particles comprising the polymer and wax.
  • the electrophotographic composition may include other additives.
  • the varnish composition may include a crosslinking or curing agent, for example, an epoxy crosslinking agent.
  • the varnish composition may also include a catalyst and/or photoinitiator to catalyse or initiate the crosslinking or curing reaction.
  • Crosslinking or curing may be initiated, for example, on the intermediate transfer member or blanket, before the composition is transferred to the print substrate.
  • crosslinking or curing may be initiated by UV light.
  • the degree of crosslinking is controlled to ensure that the crosslinked or cured composition can still flow when the composition is heated to at least 120 degrees C.
  • crosslinking agents may also be absent.
  • the electrophotographic varnish composition comprises less than 1 weight %, for example, less than 0.5 weight %, less than 0.2 weight % or less than 0.1 weight % of crosslinking agent based on the total weight of solids in the composition. In some examples, the electrophotographic varnish composition is non-crosslinkable or uncross-linked.
  • the electrophotographic compositions as described in this disclosure is printed onto a substrate using a liquid electrophotographic printer.
  • the liquid electrophotographic printer may be used to print the electrophotographic ink composition onto the substrate to form a printed image.
  • the liquid electrophotographic printer may also be used to print the electrophotographic varnish composition over the printed image.
  • the image that is formed on the photoconductive surface is a latent electrostatic image having image and background areas with different potentials.
  • the charged toner particles adhere to the image areas of the latent image while the background areas remain clean.
  • the image is then transferred to a print substrate (e.g. paper) either directly or by first being transferred to an intermediate transfer member (e.g. a soft swelling blanket) and then to the print substrate.
  • the intermediate transfer member if present, may be a rotating flexible member, which may be heated, e.g. to a temperature of from 80 to 105 degrees C.
  • the electrophotographic varnish composition may be printed onto the print substrate after the electrophotographic ink composition has been printed onto the substrate in the same print cycle.
  • the varnish composition is printed as a final separation, or print step, after all print separations relating to the image have been printed.
  • References to print separation, or print step are to be understood as referring to a single iteration of the three major transfer steps of the printing process: the transfer of an electrophotographic composition from a binary developer to the photo imaging plate (PIP), followed by transfer (known as t 1 transfer) from the PIP to an intermediate transfer member (ITM), and finally another transfer (known as t 2 transfer) from ITM to the print substrate.
  • the ink formulations are printed in turn, or separately, hence print separations.
  • the varnish composition is printed as a final separation after all CMYK ink separations have taken place, i.e. all inks have been transferred to the substrate.
  • the varnish composition is printed simultaneously with the last ink separation.
  • the intermediate transfer member operates at a temperature in the region of 80 to 1 10 degrees C. This temperature may be sufficient to heat e.g. an electrophotographic varnish composition on the ITM, for example, so as to activate any crosslinking agent, curing agent or catalyst present.
  • the varnish composition is at least partially cured, if not fully cured by the time that it is transferred to the print substrate.
  • the method of the present disclosure comprises the step of heating the electrophotographic varnish composition, for example, to a temperature of 80 to 1 10, for example, 90 to 105 degrees C prior to depositing the electrophotographic varnish composition onto the print substrate.
  • the print substrate may be left to cool. Thereafter, the print substrate bearing the printed varnish may be heated to a temperature of at least 120 degrees to enhance the gloss of the varnished image.
  • the printing method may further include the step of controlling the heating step to increase the gloss of the varnished image relative to the gloss of the varnished image prior to heating. This control step may be carried out by visual inspection or by measuring the gloss value of the varnished image after heating and comparing the gloss value to a reference value.
  • the print substrate bearing the varnished image may be heated to a temperature of at least 120 degrees C in an in-line process.
  • the print substrate bearing the varnished image may be heated shortly after the varnished image is produced.
  • the heating step may be applied to varnished substrates that have been printed and stored for a period of time.
  • the heating step may be a post-treatment step that may not necessarily be carried out in an in-line process.
  • the print substrate may be any suitable substrate.
  • the substrate may be any suitable substrate capable of having an image printed thereon.
  • the substrate may include a material selected from an organic or inorganic material.
  • the material may include a natural polymeric material, e.g. cellulose.
  • the material may include a synthetic polymeric material, e.g. a polymer formed from alkylene monomers, including, but not limited to, polyethylene and polypropylene, and co-polymers such as styrene-polybutadiene.
  • the polypropylene may, in some examples, be biaxially orientated polypropylene.
  • the material may include a metal, which may be in sheet form.
  • the metal may be selected from or made from, for instance, aluminium (Al), silver (Ag), tin (Sn), copper (Cu), mixtures thereof.
  • the substrate includes a cellulosic paper.
  • the cellulosic paper is coated with a polymeric material, e.g. a polymer formed from styrene-butadiene resin.
  • the cellulosic paper has an inorganic material bound to its surface (before printing with ink) with a polymeric material, wherein the inorganic material may be selected from, for example, kaolinite or calcium carbonate.
  • the substrate is, in some examples, a cellulosic print substrate such as paper.
  • the cellulosic print substrate is, in some examples, a coated cellulosic print.
  • a primer may be coated onto the print substrate, before the electrostatic composition is printed onto the print substrate.
  • the varnished image is heated to a temperature of at least 120 degrees C.
  • the heating may be carried out by placing or transferring the varnished substrate into an oven.
  • a hot roll press may be used.
  • the varnished print substrate may be heated with, for example, infrared (700nm to 1 mm) radiation to heat the varnish to at least 120 degrees C.
  • near infrared (700 - 1200 nm) radiation is used in the heating step.
  • the heating may be carried out by irradiation with e-beam radiation.
  • the temperature and duration of the heating step may be controlled to at least partially melt the printed varnish and achieve the desired level to gloss.
  • Gloss paper substrates Euroart®, was electrophotographically printed with commercially available yellow (Y), magenta (M), cyan (C) and black (K)
  • the varnish resins (Nucrel®925/Nucrel®2806/LOTADER® AX8900 at 720/180/100 weight ratio, respectively) were melted under constant mixing at 140° C. The melt process was carried out slowly over an average of 2 hours. The resulting mixture was then cooled to 80 ° C under constant mixing at a cooling rate of 0.5
  • a varnish ink solids (10-13%, NVS) in a jerry can was allowed to mix in a shaker (200 rpm) for at least 24 h prior to processing.
  • a 2% NVS varnish ink is prepared by diluting a predetermined solid content with an iso-paraffinic carrier, lsopar®-L.
  • the corresponding charge director (CD) was added at 2-15 mg/g (mg of CD per g of solid, w/w) and allowed to mix in a shaker (200 rpm) for 24 h to reach sufficient charging and homogenization.
  • Electroink® transparent varnish was printed as a final separation (s) on top of YMCK print.
  • the transparent varnish increases the measured gloss.
  • Higher gloss values increase up to 30 GU, were achieved by applying a hot-roll laminator (130 °C after printing).
  • the hot-roll laminator caused the polymer resin in the varnish to melt and flow over the substrate as a smooth surface, increasing its gloss.
  • increase in gloss after hot roll lamination was higher in 1 and 2 varnish layers compared to 3 and 4 layers.
  • Table 1 measured gloss (75°) of 100% solid K with transparent layers before and after hot roll lamination at 130°C.

Abstract

La présente invention concerne un procédé d'impression consistant à imprimer par voie électrophotographique une composition d'encre électrophotographique sur un substrat d'impression de sorte à former une image imprimée sur le substrat d'impression. Une composition de vernis électrophotographique transparent est imprimée par voie électrophotographique sur l'image imprimée de sorte à former une image vernie. L'image vernie sur le substrat d'impression est chauffée à une température supérieure ou égale à 120 °C.
PCT/EP2016/074367 2016-10-11 2016-10-11 Impression électrophotographique WO2018068837A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/EP2016/074367 WO2018068837A1 (fr) 2016-10-11 2016-10-11 Impression électrophotographique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2016/074367 WO2018068837A1 (fr) 2016-10-11 2016-10-11 Impression électrophotographique

Publications (1)

Publication Number Publication Date
WO2018068837A1 true WO2018068837A1 (fr) 2018-04-19

Family

ID=57133178

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2016/074367 WO2018068837A1 (fr) 2016-10-11 2016-10-11 Impression électrophotographique

Country Status (1)

Country Link
WO (1) WO2018068837A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3714331A4 (fr) * 2018-04-30 2021-01-06 Hewlett-Packard Development Company, L.P. Impression électrophotographique

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7785761B2 (en) * 2004-03-26 2010-08-31 Fuji Xerox Co., Ltd. Transparent toner, developer including same, gloss-providing unit and image forming device
WO2016116140A1 (fr) * 2015-01-20 2016-07-28 Hewlett-Packard Indigo B.V. Impression électrophotographique et lustrage

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7785761B2 (en) * 2004-03-26 2010-08-31 Fuji Xerox Co., Ltd. Transparent toner, developer including same, gloss-providing unit and image forming device
WO2016116140A1 (fr) * 2015-01-20 2016-07-28 Hewlett-Packard Indigo B.V. Impression électrophotographique et lustrage

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3714331A4 (fr) * 2018-04-30 2021-01-06 Hewlett-Packard Development Company, L.P. Impression électrophotographique
US11392053B2 (en) 2018-04-30 2022-07-19 Hewlett-Packard Development Company, L.P. Electrophotographic printing

Similar Documents

Publication Publication Date Title
EP3295250B1 (fr) Matériau imprimé souple
EP2922701A1 (fr) Procédés d'impression sur un substrat de plastique et compositions d'encre électrostatique
US10197931B2 (en) Electrophotographic varnish
EP2999997A1 (fr) Impression électrostatique
WO2018019379A1 (fr) Composition d'encre électrophotographique liquide
CN107533310B (zh) 电子照相清漆组合物
EP3123248A1 (fr) Composition de vernis électrophotographique liquide
EP3414626A1 (fr) Étiquettes
WO2016116140A1 (fr) Impression électrophotographique et lustrage
US9857717B2 (en) Liquid electrophotographic ink composition
US20190055421A1 (en) Electrostatic ink composition
US20180231904A1 (en) Electrophotographic composition
WO2018068837A1 (fr) Impression électrophotographique
EP3374829A1 (fr) Impression sélective
US10474052B2 (en) Electrophotographic composition
US10168629B2 (en) Liquid electrophotographic varnish composition
US10353325B2 (en) Liquid electrophotographic composition
EP3914968A1 (fr) Composition d'encre électrostatique
WO2023195991A1 (fr) Compositions d'encre électrophotographique
WO2022240401A1 (fr) Compositions de couche primaire
EP3837324A1 (fr) Compositions d'encre électrophotographique

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16781382

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16781382

Country of ref document: EP

Kind code of ref document: A1