Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
  • D21H17/68—Water-insoluble compounds, e.g. fillers, pigments siliceous, e.g. clays
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/50—Recording sheets characterised by the coating used to improve ink, dye or pigment receptivity, e.g. for ink-jet or thermal dye transfer recording
  • B41M5/52—Macromolecular coatings
  • B41M5/5218—Macromolecular coatings characterised by inorganic additives, e.g. pigments, clays
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/50—Recording sheets characterised by the coating used to improve ink, dye or pigment receptivity, e.g. for ink-jet or thermal dye transfer recording
  • B41M5/52—Macromolecular coatings
  • B41M5/5245—Macromolecular coatings characterised by the use of polymers containing cationic or anionic groups, e.g. mordants
• • 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
  • D21H17/44—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups cationic
  • D21H17/45—Nitrogen-containing groups
• • 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
  • Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
  • Y10T428/259—Silicic material
• • 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
  • Y10T428/27—Web or sheet containing structurally defined element or component, the element or component having a specified weight per unit area [e.g., gms/sq cm, lbs/sq ft, etc.]
  • Y10T428/273—Web or sheet containing structurally defined element or component, the element or component having a specified weight per unit area [e.g., gms/sq cm, lbs/sq ft, etc.] of coating

Definitions

• the invention relates to a recording sheet for ink jet recorders.
• JP-OL 55-51583 describes a recording sheet for ink jet pens coated with non-colloidal silica powder
• JP-OL 56-148583 describes a recording sheet in which a base paper is coated with a mixture of a finely divided silica and a water-soluble resin
• JP-OL 57-107879 describes a recording sheet made with a mass of a synthetic silica and an aqueous binder is coated at least twice with a total coating amount of at least 10 g / m2.
• silicas obtained by the wet precipitation process, the gel process, the dry process, etc. the dry process consisting in hydrolysis of the silicon tetrachloride in a detonating gas flame.
• silica obtained by the wet precipitation method and the gel method are mainly used today; they are described in the above JP publications.
• This JP-OL essentially describes the following processes: a process in which an ink-receiving layer, which has been obtained by coating a carrier with synthetic amorphous silicon dioxide in a coating amount of at least 10 g / m 2, is coated with ultrafine silicon dioxide, and a process in which is coated on a support with a mixture of an ultrafine silica and a silica obtained by the precipitation method in a certain mixing ratio and in a coating amount of 15 g / m2. So this is a coating of more than 10 g / m2. Therefore, the technology described in JP-OL 60-204390 is substantially the same as that described in JP-OLs 55-51583, 56-148583, 57-107879, etc.
• the aim of the known methods is to produce an ink jet recording sheet having a good recording density and superior ink absorption ability, which is achieved by applying a coating composition of 10 to 20 g / m2 on a support.
• JP-OL 56-84992 describes a method in which the surface of a recording layer is coated with a polycationic polyelectrolyte.
• JP-OL 59-20696 describes a process using an ink-receiving layer containing polydimethyldiallylammonium chloride.
• a recording sheet having good lightfastness and superior image durability it is known to use a recording sheet having an ink-receiving layer containing a metal oxide, a UV absorber, an oxidation inhibitor and the like.
• JP-OL 58-177390 describes that an ink jet recording sheet, which is suitable for ink jet recorders with electric field control, by coating an ink-receiving layer made of a mixture of synthetic silicon dioxide and aqueous binder with an electrical conductor of the quaternary ammonium salt type under normal pressure can get.
• This recording sheet is not affected by changes in environmental humidity due to the presence of an electrostatic preventing agent.
• the previous ink jet recording sheets have been used to improve properties such as recording density, ink absorbency and drying, ink flow, ink flow, water resistance, light resistance, and manufacturability of an excellent sheet and image.
• Gases that cause a color change or discoloration are, for example, NO x , sulfur dioxide, etc. in exhaust gases and factory emissions, ozone from copying machines, cigarette smoke and the like.
• Ozone from copying machines is being created more and more because the miniaturization and simplification of copying machines to office machines means that many small or medium-sized copying machines are being used more and more in the office.
• the color change or discoloration of the recorded image due to oxidizing gases in closed rooms and outdoors is therefore a very big problem.
• Some of the oxidizing gases are known to excite the acidic molecules in an aqueous ink in conventional ink jet recording images.
• a fibrous carrier When a fibrous carrier is coated with a filler, including silicon dioxide, in a coating amount of approximately 10 g / m 2, the fibers are completely covered with this filler, so that the paper-like character and the paper-like feel are lost. Furthermore, these fine silicas require a larger amount of binder in the coating compared to other fillers because of the smaller volume density. Because the gaps in the coating are filled with this binder, the amount of coating must be increased further in order to obtain a good ink absorption capacity. As a result, the paper-like character and grip are lost.
• a filler including silicon dioxide
• the recording sheet which has good ink absorption ability has the disadvantages that it has poor surface strength and thereby easily creates paper dust which clogs the nozzles, etc. of the printer, thereby not using this sheet as a conventional recording sheet can be.
• the synthetic silica used as a catalyst in the oxidation reaction has a strong catalytic function. Therefore, as the amount of the coating to improve the recording density and the ink absorption ability increases, the catalytic effect also increases. In the case of the previous recording sheets, in which the synthetic silicon dioxide is applied in a large amount of coating, this leads to a considerably greater discoloration of the recording image due to the resulting oxidizing gases. The paper-like character and the grip have deteriorated.
• the metal oxides, UV absorbers, oxidation inhibitors, polycationic polyelectrolytes etc. which are used for good lightfastness and superior lightfastness of the images, are unable to prevent the discoloration by oxidizing gases. Some of these materials even cause the discoloration.
• the ink jet recording sheet Prevent discoloration by oxidizing gases, etc. while maintaining good recording density, superior ink absorbency and paper-like character.
• the invention has for its object to provide a recording sheet for ink jet pens available which, while maintaining the paper character and the good grip of the uncoated sheet, provides a uniform image, a high recording density and good multiple recording, less image discoloration by oxidizing gases and excellent image durability and high lightfastness.
• a support is coated or impregnated with an ink-receiving layer which contains a mixture of ultrafine, in particular anhydrous, silicon dioxide and a cationic resin.
• the silicas according to the invention are amorphous silicas with a high SiO2 content without an inner surface and consist of aggregates of spherical particles with an average primary particle size of 7 to 40 microns.
• the silicon dioxide is produced by hydrolysis of silicon tetrachloride in a detonating gas flame.
• the silicon dioxide according to the invention forms hydrogen bonds, in which silanol groups act as the center, and from a certain sludge concentration it has a significant increase in viscosity compared to the silicon dioxide obtained by the wet process, so that it in combination with a water-soluble resin, a binder for the previous one after Silicon dioxide obtained by the wet process, cannot be applied. It has been found that the silicon dioxide according to the invention can be applied in combination with the cationic resin according to the invention, which is the characteristic of this invention.
• the dispersion of the mixture of the ultrafine anhydrous silica and the cationic resin leads to fairly uniform aggregates, which lowers the viscosity of the slurry compared to that of the coating composition without a cationic polymer.
• the dispersed mixture according to the invention can therefore be applied and the coating obtained has a voluminous structure.
• the specific BET surface area can be in a wide range. According to the invention, many ultrafine silicas can be used regardless of the specific BET surface area. A small BET surface area lowers the recording density, and a large BET surface area leads to larger aggregates of the silica and uneven gaps into which the ink sinks, which lowers the recording density. It is therefore necessary to select the silica according to the invention with a suitable specific surface, taking into account the quality of the recording sheet, the properties of the coating composition, etc.
• the silicon dioxide preferably has a BET surface area of 50-380 m 2 / g.
• Examples of the cationic resin according to the invention are polyethyleneimines, polydimethyldiallylammonium chlorides, polyalkylene-polyamine dicyandiamide ammonium chlorides, polyalkylene polyamine dicyandiamide ammonium condensates, polyvinylpyridinium halides, polymers of (meth) acrylamide alkyl quaternary ammonium salts, polymers of (meth) -oxyalkoxy-ammonium salts, polymers of (meth) -oxychloro-ammonium salts, polymers of (meth) -oxychloro-ammonium salts, polymers of (meth) -oxychloro-ammonium salts, polymers of (meth) -oxychloro-ammonium salts, polymers of (meth) -oxychloro-ammonium salts, polymers of (meth) -oxychloro-ammonium salts, polymers of (meth) -
• the mixing ratio of the cationic resin of the present invention to the ultrafine anhydrous silica according to the present invention will vary depending on the kind, the molecular weight and the cationic charge (charge strength) of the cationic resin, the specific surface area and the particle size of the ultrafine (anhydrous) silica, and the kind and the amount of the binder simply determined. It is advantageous to use 0.2-20 parts by weight of the cationic resin based on 100 parts by weight of the ultrafine (anhydrous) silica and a mixing ratio (weight) of the cationic resin to the water-soluble binder of 1: 0-2.
• the ink-receiving layer is preferably applied in an amount of at most 10 g / m2, in particular less than 10 g / m2.
• the coating according to the invention can optionally contain various water-soluble resins as binders.
• water-soluble resins are: Starch, cationic starch, polyvinyl alcohol, cellulose derivatives such as hydroxyethyl cellulose and carboxymethyl cellulose, polyacrylamides, polyvinyl pyridine, polyethylene oxide, polyvinyl pyrrolidone, casein, gelatin, sodium alginate, polystyrene sulfonate, sodium polyacrylate, hydrolyzed starch-Acrylnitrilpropfcopolymer, sulfonated chitin, carboxylated chitin, chitosan, and their derivatives and the like.
• the binders which have low reactivity with the cationic resin of the present invention are preferred.
• the coating according to the invention (the ink-absorbing layer) predominantly contains the ultrafine (anhydrous) silicon dioxide according to the invention, possibly other fillers for improving the paper gliding property, the printability, etc.
• fillers examples include calcium carbonate, alumina, kaolin, Japanese acid soil, talc, synthetic silicon dioxide (obtained by the wet precipitation process and the gel process), aluminum oxide, aluminum hydroxide, zinc oxide, calcium silicate, synthetic silicates, titanium dioxide, diatomaceous earth, aluminum sulfate, satin white, glass powder, organic resin pigments and the like
• the coating according to the invention may also contain other chemicals, for example surface-active agents for improving the quality of the print, e.g. for the improvement of course and spot diameter.
• the carrier for the coating according to the invention must be an ink-absorbent material, for example a paper containing cavities (pores, capillaries), which is made of paper materials, waste paper, chitin, syntheti fibers, glass fibers, etc., or a mixture thereof, or a void-containing sheet such as a void-containing nonwoven fabric.
• an ink-absorbent material for example a paper containing cavities (pores, capillaries), which is made of paper materials, waste paper, chitin, syntheti fibers, glass fibers, etc., or a mixture thereof, or a void-containing sheet such as a void-containing nonwoven fabric.
• the carrier used according to the invention can optionally contain additives in the carrier or in the form of a coating on the carrier.
• the amount of additives can be chosen so that the ink absorbency, the paper-like character and the feel are not impaired.
• Examples of additives in the carrier are various fillers and other additives, and examples of additives in the form of a coating are resins and pigments, and it is desirable that the coating amount of the pigment is at most 10 g / m 2 in consideration of the paper-like character and good hand to use.
• a coating press, roller coater, knife coater, bar coater, jet machine, etc. can be used for the coating, for example.
• the object is achieved to provide an ink jet recording sheet which has the paper-like character (and appearance) and good while maintaining Griffs a uniform image, a high recording density, a good multi-color recording, a little discoloration of the image when exposed to oxidizing gases, superior durability and better lightfastness having. The reason for this is unclear.
• the coating composition which contains a mixture of the ultrafine (anhydrous) silicon dioxide and the cationic resin, gives a thick coating layer with a large number of fairly uniform, suitable gaps (cavities) due to the easy formation of hydrogen bonds by the ultrafine ( anhydrous) silicon dioxide and due to the aggregation effect of the cationic resin. Therefore, the coating amount of ultrafine (anhydrous) silicon dioxide with a strong catalyst function is considerably less than the previous coating amount. The small amount of coating results in a large number of fairly uniform gaps of a suitable size, while maintaining the paper-like character and good grip. Because of these gaps, the recording sheet of the present invention has sufficient recording density, high ink absorbency, smooth image, and good multi-color recording despite the small amount of coating. The reason for the improved image discoloration is attributed to the fact that the ultrafine silicon dioxide according to the invention has no highly catalyst-active gaps (pores) and contains only a small amount of silicon dioxide-activating impurities, such as heavy metals and their salts.
• 100 parts of a bleached hardwood sulfate pulp with 350 cs Freeness as paper stock 10 parts of kaolin (kaolinite group, spherical aggregates, average primary particle size: 0.1 ⁇ m, specific weight: 2.2) as filler, 0.15 parts of reinforced rosin sizing agent (Coropal CS, manufactured by Seiko Chemical Co.) and 1 part of aluminum sulfate were mixed and treated on the paper machine to obtain a carrier having a basis weight of 62 g / m2.
• 100 parts of ultrafine anhydrous silica (mean primary particle size: 12 ⁇ m, BET specific surface area: 200 m 2 / g) was dispersed in about 1264 ml of water.
• a recording sheet of Comparative Example 2 was obtained in the same manner as in Comparative Example 1, but 62.5 parts of a fine silica G prepared by the wet gel process (50% average particle size: 10 ⁇ m; BET specific surface area: 300 m 2 / g) ) and 37.5 parts of an ultrafine anhydrous silica instead of the fine silica F of Comparative Example 1 prepared by the wet precipitation process.
• the recording sheet of Example 1 has a good dot density, a low image discoloration, expressed as ozone resistance, a high surface strength, while maintaining the paper-like character and good grip, despite the small amount of coating , making this sheet preferred as an ink jet recording sheet.
• the recording sheet of Comparative Example 1 which is a conventional recording sheet, has a strong discoloration and, because of the large amount of coating, a poor paper-like character and an inferior feel.
• the recording sheet of Comparative Example 2 like that of Comparative Example 1, has a strong discoloration and a poor paper-like impression and an inferior feel because it contains about 30% of the ultrafine anhydrous silica, based on the filler, but no cationic resins.
• the recording sheets of Comparative Examples 3 and 4 have due to the Use of a silica produced by the wet process has strong discoloration and poor surface strength despite the small amount of coating and despite the use in combination with a cationic resin.
• Example 2 An ultrafine silica, a water-soluble binder and a cationic resin were mixed in the mixing ratio shown in Table 2 to prepare a coating composition.
• the coating composition was applied to the support used in Example 1 in a coating amount of about 2 g / m 2 by a Meyer stick. Recording sheets of Examples 2, 3 and 4 and Comparative Example 6 were obtained.
• the recording sheets according to the invention despite the small amount of coating, have good dot density, little discoloration and a superior surface strength while maintaining the paper-like character of conventional paper.
• the recording sheet of Comparative Example 6 which contains no cationic resin, gives a very poor surface strength, whereby the ultrafine anhydrous silica has not been fixed on the surface of the support, and therefore the filler powder is separated.
• This sheet is unsuitable for manufacture and use.
• Recording sheets of Examples 9, 10 and 11 were obtained in the same manner as in Example 3 except that a coating amount of 1 g / m2, 3 g / m2 and 7 g / m2 (solids content) was used instead of the coating amount of 2 g / m2. m2 used.
• a coating amount of 1 g / m2, 3 g / m2 and 7 g / m2 (solids content) was used instead of the coating amount of 2 g / m2. m2 used.
• a recording sheet of the present invention is obtained by controlling the mixing ratio of the binder to the cationic resin or the mixing ratio of the ultrafine anhydrous silica to the cationic resin.
• Dots are printed on a four-color recording sheet (black, cyan, magenta and yellow) at a constant pitch using a multi-color printer (10-735, manufactured by Sharp Co.).
• the reflectance of each dot is determined using a microdensitometer (PDM 5B.BR, manufactured by KONISHIROKU PHOTO IND. CO., LTD.).
• the test conditions are as follows: integrated magnification: 20x, slot width: 25 ⁇ m, slot height: 25 ⁇ m, Step shift speed: 25 ⁇ m / s.
• the respective recording densities of the four colors were added and are given in tables.
• the recording sheets with a total color density of 5 or more were rated "Good".
• a recording sheet is printed with a black ink for PJ-1080 A ink jet printer (manufactured by Canon Co.) using a Bristow device (contact time: 0.01 s, ink amount: about 20 ml / m 2).
• the printed sheet is placed in a 20 ml volume desiccator.
• An ozone amount of 0.0003 g / min from the ozonizer IOP-O (manufactured by Simon Co.) is passed through the desicator together with a certain amount of air. After a minute of ozone treatment, the color difference between the printed part and the unprinted part is measured before and after the ozone treatment. The percentage discoloration is calculated using the following formula, whereby the ozone resistance is assessed.
• the recording sheets with an ozone resistance of 10 and below are rated "good".
• a recording sheet is printed with magenta ink using a Bristow device (contact time: 0.01 s, amount of ink: about 20 ml / m 2).
• the printed recording sheet is treated for 40 hours with a discoloration tester (BH model, using a carbon arc lamp manufactured by Toyo Seiki Co.).
• the color difference of the printed parts compared to the unprinted part before and after the treatment is measured.
• the percentage discoloration is calculated according to the following formula, and the light resistance is evaluated.
• the recording sheets with a light resistance of 10 or less are rated as "good".
• F S F1 / F0 x 100 (%)
• Example 5 Example 6 Example 3 Example 7 Example 8 Coating mass Ultrafine silica A 100 Ultrafine silica B 100 Ultrafine Silicon Dioxide C 100 Ultrafine silica D 100 Ultrafine silica E 100 Polyvinyl alcohol A 10th 10th 10th 10th Cationic resin A 5 5 5 5 5 Coating quantity (g / m2) 2.0 2.0 2.0 1.9 2.5 Recording density: Dot recording density 5.35 5.48 5.35 5.24 5.00 Resistance to ozone 4.1 5.7 6.1 7.4 4.5 Paper property: Surface strength A A A A A Example 9 Example 3 Example 10 Example 11 Coating compound: Ultrafine silica A 100 100 100 100 100 Polyvinyl alcohol A 10th 10th 10th 10th Cationic resin A 3rd 5 5 3rd Coating quantity (g / m2) 1.2 2.0 3.4 6.6 Recording density: Dot recording density 5.22 5.35 5.84 6.50 Resistance to ozone 4.3 6.1 7.2 9.2 Paper property: Surface strength A A B B Example 12 Example 13 Example 14 Coating compound: Ultrafine silica A 100
• LBKP 100 parts LBKP with 350 ml Freeness were used as paper stock for a carrier. 25 parts of an ultrafine anhydrous silicon dioxide (average primary particle size: 12 nm; BET specific surface area: 200 m 2 / g) as filler and 2 parts of a cationic resin (polydimethyldiallyl quaternary Ammonium salts; average molecular weight: 120,000) was added. Further, 0.15 part of a reinforced rosin sizing agent (Coropal CS, manufactured by Seiko Kogyo Co.) and 1.0 part of aluminum sulfate were added. A 64 g / m2 basis weight sheet was produced by a paper machine, and the resulting sheet was supercalendered to prepare the recording sheet of Comparative Example 7.
• a recording sheet of Example 8 was prepared in the same manner as in Example 7, except that 50 parts of the ultrafine anhydrous silica was used instead of 25 parts.
• a 6% aqueous solution of polyvinyl alcohol (degree of saponification: more than 99%; average degree of polymerization: 1700) was applied to the recording sheet of Comparative Example 8 by means of a Meyer stick in a coating amount of about 2 g / m2, dried and supercalendered to form a recording sheet of Comparative Example 9.
• the ink jet recording sheet of the present invention is made by coating a support with a coating composition containing a mixture of an ultrafine anhydrous silica and a cationic resin.
• the recording sheet according to the invention has a uniform image quality, a high recording density, good multi-color recording and little discoloration of the image due to oxidizing gases while maintaining the paper character and good grip. Furthermore, the recording sheet according to the invention is economically advantageous because of the small amount of coating required.

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• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Dispersion Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Ink Jet Recording Methods And Recording Media Thereof (AREA)
• Paper (AREA)

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• 1989
  • 1989-01-18 JP JP1008993A patent/JP2633671B2/ja not_active Expired - Lifetime
• 1990
  • 1990-01-09 CA CA002007373A patent/CA2007373C/fr not_active Expired - Fee Related
  • 1990-01-17 US US07/466,629 patent/US5165973A/en not_active Expired - Lifetime
  • 1990-01-17 EP EP90100957A patent/EP0379964B1/fr not_active Revoked
  • 1990-01-17 DE DE59006086T patent/DE59006086D1/de not_active Revoked

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