JP4540631B2 - Pressure sensitive copying color developing sheet for ink jet recording - Google Patents

Description

  The present invention relates to a pressure-sensitive copying developer sheet for ink jet recording. More specifically, pressure-sensitive copying for ink-jet recording is capable of producing clear recorded images without bleeding or image density reduction when wet, and maintaining sufficient color developability and color density as pressure-sensitive copying paper. It relates to the developer sheet.

  Pressure-sensitive copying paper consists of an upper paper coated with a color former microcapsule composition mainly composed of microcapsules encapsulating an oily substance in which an electron-donating organic color former is dissolved, and the surface of the support. A medium paper having an electron-accepting developer as a main component that develops a color when it comes into contact with the color former, and a color developer microcapsule composition coated on the back surface; It consists of a lower paper having a developer composition coated on the surface, and is generally used in the order of upper paper-lower paper or in the order of upper paper-middle paper-lower paper. In such pressure-sensitive copying paper, the microcapsules are destroyed by the pressure of the writing pressure, printer, etc., and the oil in which the color former is dissolved is transferred to the developer layer and develops a color by reacting with the developer. It has become. In addition, a self-coloring type pressure-sensitive copying paper in which a color former and a developer are coated on the same surface of a support and pressure-sensitive recording can be performed with one sheet is also known as one form.

  Developers used in the pressure-sensitive copying paper include inorganic developers such as acid clay, activated clay and attapulgite, phenol-formaldehyde resin, polyvalent metal salt of salicylic acid derivative, polyvalent metal of terpene phenol resin. Organic developers such as salts and polyvalent metal salts of salicylic acid-containing copolymers are known.

  Pressure-sensitive copy paper is used in various slips, and is used as a copy set of upper paper and lower paper, or as a set of many copies with the required number of intermediate sheets sandwiched between the upper paper and lower paper. . In some cases, self-coloring pressure-sensitive copying paper is incorporated into the copy set. Each sheet of the copy set needs to be bonded so that it does not fall apart and is separated one by one with the minimum necessary force.

  In the past, slips made of pressure-sensitive copying paper have been used after being form-printed by offset printing, letterpress printing, etc. In recent years, with the technical development of ink-jet recording methods, examples of using ink-jet recording methods for form printing have been used. Has come to be seen. When using the inkjet recording method, there are advantages such as eliminating the need for plate making and easy format change. Printing of small lots or variable information such as barcodes for each individual sheet of a slip is possible. Or, since it can be used for printing, printing or printing by an ink jet recording method has been widely used for pressure-sensitive copying paper.

  However, the ink jet recording image formed on the conventional pressure-sensitive copying paper using the ink jet recording method has problems such that the water resistance is low and the ink jet recording image is blurred or the image density is lowered when wet. In addition, there is a drawback in that the ink oozes out when a recorded image is formed, and a clear image quality cannot be obtained.

  Therefore, as a pressure-sensitive copying paper for improving the above-mentioned problem, for example, Patent Document 1 discloses that a colorant-containing layer contains a cationic substance having a quaternary ammonium group or a tertiary amino group for inkjet recording. A pressure sensitive copying paper is disclosed.

  However, in order to stabilize the viscosity of the coating solution, it is usually desirable that the coating solution for the developer layer is anionic. However, as in the pressure-sensitive copying paper disclosed in Patent Document 1, an anionic developing color is used. When a colorant containing a cationic substance is added to the coating liquid for the agent layer, the coating liquid becomes thickened or gelled, which makes coating very difficult. In addition, the cationic substance acts on the developer and the color developing ability is lowered, and the color density is also lowered, resulting in a problem that sufficient quality as pressure-sensitive copying paper cannot be obtained.

  Further, in Patent Document 2, inkjet recording is performed by adjusting the contact angle measured after 10 seconds by dropping distilled water onto the surface of the developer layer containing an electron-accepting developer to 70 to 120 degrees. A developer sheet for pressure-sensitive copying which attempts to impart appropriateness is disclosed.

  However, the pressure-sensitive copying developer sheet disclosed in Patent Document 2 is characterized in that an acrylic resin emulsion is blended together with an electron-accepting developer in the developer layer, and is used in an ink jet recording system. When applied, there is a problem that the long-term stability of the developer is impaired, the color image is blurred, the color developability is lowered, and the ink fixing property is inferior.

Furthermore, in Patent Documents 3 and 4, a surface treatment layer and a developer coating layer are sequentially provided on a support, and the degree of cobb sizing with isopropyl alcohol is set to 20 to 60 g / m ² , thereby imparting ink jet recording suitability. No-carbon feel that imparts ink jet recording suitability by attaching an alkylamine / epihalohydrin polycondensate to a no-carbon pressure-sensitive copying paper or one side of the support, and adjusting the degree of sizing of 10 seconds to 7-12 g / m ² . A copier paper is disclosed.

However, in the carbonless pressure-sensitive copying paper disclosed in Patent Documents 3 and 4, the surface of the copying paper is treated with a treatment liquid containing a cationic resin or an alkylamine / epihalohydrin polycondensate having a specific molecular weight or less. Although the water resistance is improved to some extent, when applied to the ink jet recording method, there are problems that the ink is poor in dryness of absorption and inadequate in pressure sensitive recording.
JP-A-3-236986 Japanese Patent Laid-Open No. 10-16383 JP-A-10-264515 JP 2001-270243 A

  The present invention has been made in view of the above-mentioned background art, and when wetted with water, there is no bleeding or a decrease in image density, a clear recorded image is obtained, and sufficient color developability and color development as pressure-sensitive copying paper An object of the present invention is to provide a pressure-sensitive copying developer sheet for ink-jet recording capable of maintaining the density.

  That is, the present invention is a developer sheet comprising a base paper and a developer layer on one main surface of the base paper, wherein the developer layer is a paint mainly containing a pigment, a developer and a binder. The present invention relates to a pressure-sensitive copying color developing sheet for ink-jet recording, characterized in that it contains regenerated particles formed mainly from deinked floss as the pigment.

  The pressure-sensitive copying color developing sheet for ink-jet recording of the present invention does not cause bleeding or a decrease in image density when wet with water, provides a clear recorded image, and has sufficient color developability and color density as pressure-sensitive copying paper. And can be suitably used for printing or printing by an ink jet recording method.

(First embodiment)
As described above, the pressure-sensitive copying developer sheet for ink-jet recording of the present invention comprises a base paper and a developer layer on one main surface of the base paper, and the developer layer contains a pigment, a developer and a binder. It is formed by a paint mainly blended, and contains regenerated particles made mainly from deinked floss as the pigment.

  First, the base paper used in this embodiment will be described. There are no particular limitations on the type of raw material pulp that constitutes the base paper, and pulp that is used in ordinary developer sheets can be used as appropriate.

  As the raw material pulp, for example, kraft pulp (SP), soda pulp (AP), hardwood bleached kraft pulp (LBKP), softwood bleached kraft pulp (NBKP) and the like, which are usually used for the production of fine paper, etc. KP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), semi-chemical pulp (SCP), refiner ground pulp (RGP), chemiground pulp (CGP), groundwood pulp (GP), pressurized stone grand pulp Examples thereof include mechanical pulps such as (PGW), and these can be used alone or in combination of two or more. In addition to these, bleached pulp (BPGW) crushed under pressure and virgin pulp bleached can be used, but when virgin pulp is bleached, a bleaching method that does not use chlorine should be adopted. Is preferred. That is, when using bleached pulp, it is desirable to use pulp bleached by chlorine-free bleaching such as Total Chlorine Free (TCF) and Elemental Chlorine Free (ECF). Such chlorine-free bleached pulp does not use elemental chlorine and hypochlorous acid, and is subjected to ozone bleaching or oxygen bleaching. Although not clear, the end groups of fibers (cellulose) constituting the pulp are not clear. Since it is activated by oxygen, for example, it is a pulp that has a high affinity with a cationic wet paper strength agent or an anionic dry paper strength agent, and exhibits a paper strength improvement effect more suitably.

  On the other hand, as used paper pulp, used paper pulp that has been bleached, in particular, reduced-bleached with thiourea dioxide (FAS), can be suitably used. The reason why FAS-bleached waste paper pulp is not clear compared to conventional chlorine-bleached pulp is high in affinity with, for example, cationic wet paper strength agent and anionic dry paper strength agent, and has an effect of improving paper strength. It is more suitably demonstrated, and environmental protection and cost reduction can be realized.

  In this embodiment, when mechanical pulp is used as the raw material pulp, the content in the raw material pulp is 5% by mass or more as measured according to “Fiber composition test method” described in JIS P 8120. preferable. By using 5% by mass or more of mechanical pulp in this way, a pressure-sensitive copying color developing sheet for ink-jet recording is obtained, for example, in a multi-layered manner. It can be a pressure-sensitive copy slip sheet or the like that is easy to turn. In consideration of sufficiently maintaining the surface strength of the base paper and suppression of paper dust, the content of mechanical pulp in the raw pulp is preferably 50% by mass or less.

  Moreover, from the viewpoint of improving the water resistance of the color developing sheet for pressure-sensitive copying paper, specifically, improving the paper strength of the base paper, the raw material pulp disaggregated in accordance with the “pulp-disaggregation method” described in JIS P 8220, It is beaten so that the Canadian Standard Freeness (hereinafter referred to as CSF) conforming to “Pulp Freeness Test Method” described in JIS P 8121 is 300 ml or more, 350 ml or more, 600 ml or less, and 550 ml or less. It is preferable that When the CSF of the raw material pulp is less than 300 ml, the paper strength improvement effect is not manifested, and the stiffness and strength of the base paper itself may be reduced, and printability may be reduced. Further, when the CSF of the raw material pulp exceeds 600 ml, the formation is deteriorated, the printability in the ink jet recording method may be deteriorated, the surface strength unevenness of the base paper due to uneven formation, There may be problems with adhesive strength. Note that a known beating machine such as a refiner or a kneader is used for beating the raw material pulp, but the CSF of the raw material pulp can be adjusted by classifying the short fiber and the long fiber using a classifier. By appropriately adjusting the treatment concentration and treatment time, a raw material pulp having a CSF within the above range can be obtained.

  When obtaining the base paper, additives can be appropriately blended with the raw material pulp. There are no particular limitations on such additives. For example, light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, satin white, aluminum silicate, diatomaceous earth. Soil, calcium silicate, magnesium silicate, synthetic silica, aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide and other inorganic pigments, styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea Fillers for organic pigments such as resins and melamine resins; rosin sizing agent for acidic papermaking, modified rosin sizing agent for neutral papermaking, alkenyl succinic acid sizing agent, alkyl ketene dimer sizing agent, alkenyl succinic anhydride sizing agent Internal sizing agents such as wax-based sizing agents, styrene resin-based sizing agents, olefin resin-based sizing agents, styrene-acrylic resin-based sizing agents, higher fatty acid-based sizing agents, and cationic polymer-type sizing agents; starch, modified starch, plant gum Various papermaking agents such as paper strength enhancers such as carboxymethylcellulose and polyacrylamide; yield improvers; freeness improvers; and UV inhibitors can be used.

There is no particular limitation on the basis weight of the base paper, and the basis weight of a general developer sheet of about 30 to 200 g / m ² measured in accordance with the “basis weight measurement method” described in JIS P 8124. That's fine.

  Next, a paint for forming a developer layer on one main surface of the base paper will be described. The paint used in this embodiment mainly contains a pigment, a developer, and a binder, and contains regenerated particles mainly made of deinked floss as the pigment.

  As described above, one of the major features of this embodiment is that a pigment containing specific regenerated particles mainly made of deinked floss is used in the paint, and the developer layer is formed with the paint. As a result, it has a high affinity with binders and inkjet inks that normally exhibit anionic properties, excellent absorption and drying properties of inkjet inks, and there is no bleeding or decrease in image density when wet, resulting in clear recorded images. In addition, it is possible to obtain a pressure-sensitive copying color developing sheet for ink-jet recording which maintains a sufficient color density as pressure-sensitive copying paper.

  The regenerated particles used in the present embodiment are particles obtained using, for example, at least a dehydration step, a drying step, a firing step, and a pulverization step using deinked floss as a main raw material (50% or more of the raw material). , Calcium, silicon and aluminum. The aluminum is mainly derived from aluminum in clay, trivalent aluminum sulfate added as an auxiliary in the papermaking process, 18 hydrate, and aluminum contained in talc as impurities. Compared to conventional inorganic fillers exhibiting anionic properties, aluminum has improved binding strength with anionic pulp fibers, so that the yield and chemical fixability are improved by containing aluminum.

  On the other hand, since the silica primary particles made of silicon are fine, the optical refractive index is high, and the inclusion of silicon improves opacity.

  On the other hand, calcium, for example, has the effect of improving the whiteness of paper when it is internally added to the raw material pulp. Here, the calcium carbonate has homogeneous images such as hexagonal calcite crystal (calcite) and orthorhombic aragonite crystal (aragonite). Most limestones produced in nature are calcite crystals, and shellfish contain aragonite crystals in addition to calcite crystals. Furthermore, although not natural, calcium carbonate also has vaterite crystals. There are various kinds of calcium obtained from the deinking floss, but it becomes a substantially uniform calcium carbonate property by calcination and aggregation. Therefore, the calcium contributes to the quality stability of the regenerated particles themselves, and the regenerated particles are agglomerates composed of different components such as calcium, silicon, and aluminum, and exhibit a porous and stable cushioning property.

  Here, the ratio of calcium, silicon and aluminum in the regenerated particles was measured by elemental analysis with an X-ray microanalyzer (model number: E-MAX S-2150, manufactured by Hitachi, Ltd./Horiba, Ltd.). In view of the fact that the affinity with an ink jet ink that is anionic, the binder contained in the developer layer, and various auxiliaries is further improved, the ratio suitable for this embodiment is an oxide conversion And calcium: silicon: aluminum in a mass ratio of 30-82: 9-35: 9-35, further 40-82: 9-30: 9-30, especially 60-82: 9-20: 9-20. is there. In particular, when the regenerated particles are silica-coated regenerated particles described later, the ratio of calcium, silicon, and aluminum is 30: 62: 29-55: 9-35 for calcium: silicon: aluminum in terms of oxides. It is preferable that The total content of calcium, silicon and aluminum in the regenerated particles is preferably 90% by mass or more, particularly preferably 93% by mass or more in terms of oxide, as measured by the elemental analysis.

  As a method for adjusting the ratio of calcium, silicon and aluminum in the regenerated particles in terms of oxides, for example, a method of adjusting the raw material composition in deinking floss, as well as coating with a clear source in the drying / classification process and firing process It is also possible to employ a method of containing floss or adjusting process froth in the process by spraying, a method of containing incinerator scrubber lime, or the like.

  Furthermore, for example, the amount of neutral papermaking wastewater sludge and the amount of wastewater sludge from the coated paper manufacturing process are adjusted for the adjustment of calcium in the regenerated particles, and the amount of newspaper added as an opacity improver for the adjustment of silicon. For the adjustment of aluminum using paper manufacturing wastewater sludge, papermaking wastewater sludge such as acidic papermaking and the like, and wastewater sludge in high-quality papermaking processes that frequently use clay can be used as appropriate. In this case, when adjusting the total content ratio of calcium, silicon and aluminum to 90% by mass or more in terms of oxide, it is achieved by selectively removing iron, which is a causative substance that lowers whiteness by oxidation. As the method, for example, a method of using a flocculant that does not contain iron for the agglomeration treatment of drainage sludge, the manufacturing equipment process is designed or lined with a material other than iron, and the iron content is brought into the system by abrasion or the like. It is possible to employ a method of preventing iron contamination by installing a high magnetic material such as a magnet in a drying / classifying facility.

  The regenerated particles used in this embodiment preferably have an oil absorption of about 30 to 100 ml / 100 g.

  On the other hand, when obtaining regenerated particles, it is preferable to treat the particles having a particle size of 40 μm or less to 90% or more before the pulverization step after the dehydration step, the drying step and the firing step. This makes it possible to perform wet one-stage pulverization without performing multi-stage pulverization such as large particle pulverization by dry pulverization and fine pulverization by wet pulverization, and the variation in particle size of individual particles can be achieved. Can be small.

  In addition, when obtaining regenerated particles, it is desirable to provide various sensors in the remanufactured particle production facility to control the condition of the object to be processed, the facility, the processing speed, and the like.

  In the previous step of the drying process, it is preferable to granulate the deinked floss that has been subjected to dehydration treatment, and it is more preferable to classify the granulated product to make the particle size uniform. The quality can be further stabilized by feeding back coarse or fine granulated particles to the previous process. In granulation, ordinary granulation equipment can be used, and equipment such as a rotary type, a stirring type, and an extrusion type is preferable.

  It is preferable to remove foreign substances other than regenerated particles in the production facility. For example, it is possible to remove foreign substances such as sand, plastic, metal, etc. with a pulper, screen, cleaner, etc. before reaching the deinking process of the used paper pulp manufacturing process. From the viewpoint of removal efficiency. In particular, as described above, the iron content is preferably removed by avoiding the iron content from being mixed because the oxidation causes generation of a substance causing a decrease in the whiteness of the regenerated particles. Therefore, each process is designed or lined with materials other than iron to prevent iron from being mixed into the system due to wear, etc., and a high magnetic material such as a magnet is installed in the drying / classifying equipment, etc. In particular, it is preferable to remove iron.

  The particle size of the regenerated particles used in the present embodiment is, for example, less than 0.05 μm as the secondary particles in which the primary particles are aggregated. Methanol from the viewpoints of promoting the color development reaction between the color former and the developer, promoting the absorption and drying properties of the ink jet printing ink, ensuring the fixing property, and ensuring the fluidity and pharmacy properties preferable as a paint. The dispersion solution is measured with a Coulter counter particle size distribution analyzer (TA-II type, manufactured by COULTER ELECTRONICS), and the average particle size is preferably 0.05 μm or more, more preferably 0.1 μm or more. On the other hand, if it exceeds 8 μm, the print quality may be deteriorated due to a decrease in smoothness, and the feeling of touch may be reduced. The flatness of the developer layer surface and the ensuring of proper printing, the maintenance of bulkiness and cushioning properties In view of this, the average particle size is preferably 8 μm or less, more preferably 5 μm or less.

  Furthermore, in the present invention, silica-coated regenerated particles in which the surface of the particles is coated with silica can be particularly suitably used as regenerated particles to be blended in the paint. By further depositing silica on the surface of the regenerated particles to form silica-coated regenerated particles, when blended in a paint to form a developer layer, the regenerated particles not coated with silica are used. Furthermore, the ink is excellent in the absorption drying property of the ink-jet ink, and the effects of paper whiteness, opacity, surface strength, ink absorption unevenness, and bulkiness can be remarkably improved. Moreover, in the used paper processing process in circulation use, it can be made to react with sodium hydroxide, and can contribute also to circulation use of the raw material for paper manufacture, and an inorganic particle as a buffering agent or a bleaching adjuvant.

  Here, about the silica which coat | covers the surface of reproduction | regeneration particle | grains, if it is not the silica produced naturally but the synthetic silica by some chemical reaction, it can be used without a restriction | limiting especially. Specific examples include colloidal silica, silica gel, and anhydrous silica. These synthetic silicas make use of excellent properties such as high specific surface area, high gas adsorbing capacity, fineness, permeability to pores and large adsorbing power, high adhesion, and high oil absorption. It is used in a wide range of fields. Among these, colloidal silica has a shape such as a spherical shape, a chain shape, and an amorphous shape, in which impurities are removed from a silicic acid compound to form an anhydrous silicic acid sol, and the sol is stabilized by adjusting pH and concentration. Amorphous silica. Silica gel is hydrous silicic acid obtained by decomposing sodium silicate with an inorganic acid. Anhydrous silica is obtained by hydrolysis of silicon tetrachloride.

  The method for depositing silica on the surface of the regenerated particles to obtain silica-coated regenerated particles is not particularly limited. For example, the following method can be suitably employed. First, regenerated particles are added to and dispersed in an alkali silicate solution, and after preparing a slurry, the temperature of the liquid is maintained at about 70 to 100 ° C., more preferably at a predetermined pressure in a sealed container, while heating and stirring. Add to produce silica sol. Subsequently, silica can be deposited on the surface of the regenerated particles by adjusting the pH of the final reaction solution to a range of 8-11. Silica precipitated on the surface of the regenerated particles in this way, using alkali silicate (for example, sodium silicate: water glass) as a raw material, reacts with a dilute solution of mineral acid such as sulfuric acid, hydrochloric acid, nitric acid at high temperature, Silica sol particles having a particle size of about 10 to 20 nm, obtained by hydrolysis reaction and polymerization of silicic acid.

  In addition, silica sol fine particles having a particle size of about several nanometers, which are generated by adding an acid such as dilute sulfuric acid to an alkali silicate solution such as a sodium silicate solution, cover the entire porous surface of the regenerated particles. The silica is deposited on the surface of the regenerated particles by the bond between the silica sol fine particles on the surface of the inorganic fine particles and the silicon, calcium, or aluminum included in the regenerated particles accompanying the crystal growth of the silica sol fine particles. You can also. In this case, the pH when adding the acid to the alkali silicate solution is in a neutral to weakly alkaline range, and the pH is preferably adjusted in the range of 8-11. This is because if the acid is added until the pH reaches an acidic condition of less than 7, white carbon may be generated instead of silica sol particles.

The type of the alkali silicate solution is not particularly limited, but a sodium silicate solution (No. 3 water glass) is particularly desirable from the viewpoint of easy availability. The concentration of the alkali silicate solution is such that the silica component in the regenerated particles is reduced and the silica content (SiO ₂ equivalent) in the solution is 3 so that silica does not easily precipitate on the surface of the regenerated particles. The silica deposited on the surface of the regenerated particles becomes white carbon from the form of the silica sol, and the porosity of the regenerated particles is inhibited, improving the opacity and the absorption drying property of the inkjet ink. Is preferably 10% by mass or less in order to eliminate the risk of insufficient.

  In the present embodiment, the ratio of the regenerated particles in the total amount of the pigment is 10% by mass or more, and further 20% by mass in order to eliminate the possibility that the affinity with the binder and the inkjet ink and the absorption drying property of the inkjet ink are reduced. In order to eliminate the possibility that the thickening is likely to occur or the production cost is increased due to the penetration of the binder into the regenerated particles, it is preferably 50% by mass or less, and further 40% by mass or less. Is preferred.

  If the proportion of the regenerated particles in the total amount of the pigment is less than 10% by mass, the ink-jet ink absorption effect of the regenerated particles is low, and there is a risk that the ink-jet printing suitability typified by the fixing property and absorption drying property of the ink-jet ink may be insufficient. When the amount exceeds 50% by mass, the porosity, which is the effect of retaining the regenerated particles, increases the amount of binder and auxiliary agent incorporated into the regenerated particles, relatively increases the amount of chemical used and increases costs. In pressure-sensitive copying recording, there is a possibility of causing a decrease in color developability.

  As described above, the pigment used in the present embodiment contains regenerated particles. In addition to the regenerated particles, the pigment is usually blended in a paint forming a developer layer, for example, heavy calcium carbonate, light Use at least one pigment (particle) selected from inorganic particles such as calcium carbonate, talc, clay, kaolin, titanium dioxide, synthetic silica and aluminum hydroxide, synthetic polymer fine particles such as polystyrene resin and urea formaldehyde resin, etc. You can also.

  The developer incorporated in the paint according to the present embodiment can be appropriately selected from those usually used in the field of pressure-sensitive copying paper. For example, an inorganic developer such as activated clay, acid clay, attapulgite, etc. Organic developers such as phenol resins and polyvalent metal salts thereof, salicylic acid, salicylic acid derivatives, salicylic acid-containing copolymers, and polyvalent metal salts thereof can be preferably used.

  Examples of the phenol resin include phenol formaldehyde resin, phenol acetaldehyde resin, phenol acetylene resin, terpene phenol resin, and polyvalent metal salts thereof. Examples of salicylic acid, salicylic acid derivatives, salicylic acid-containing copolymers and their polyvalent metal salts include salicylic acid, salicylate, 3-methylsalicylic acid, 6-ethylsalicylate, 5-isopropylbutylsalicylate, 5-sec- Butylsalicylic acid, 5-tert-butylsalicylic acid, 5-tert-amylsalicylic acid, 5-cyclohexylsalicylic acid, 5-n-octylsalicylic acid, 5-tert-cyclohexylsalicylic acid, 5-tert-octylsalicylic acid, 5-isononylsalicylic acid, 3 -Isododecyl salicylic acid, 5-isododecyl salicylic acid, 5-isopentadecyl salicylic acid, 4-methoxysalicylic acid, 6-methoxysalicylic acid, 5-ethoxysalicylic acid, 6-isopropoxysalicylic acid, 4-n-hexyloxy Salicylic acid, 4-n-decyloxysalicylic acid, 5-di-tert-butylsalicylic acid, 3,5-diisododecylsalicylic acid, 3-methyl-5-tert-nonylsalicylic acid, 3-tert-butyl-5-isononyl Salicylic acid, 3-isononyl-5-tert-butylsalicylic acid, 3-isodosyl-5-tert-butylsalicylic acid, nonylsalicylic acid, 3-isododecyl-6-methylsalicylic acid, 3-sec-octyl-5-methylsalicylic acid, 3-isononyl -5-phenylsalicylic acid, 3-phenyl-5-isononylsalicylic acid, 3-methyl-5- (α-methylbenzyl) -salicylic acid, 3-methyl-5 (α, α-dimethylbenzyl) -salicylic acid, 3-isononyl -5- (α-methylbenzyl) -salicylic acid, 3- (α-methylben ) -5-tert-butylsalicylic acid, 3-benzylsalicylic acid, 3- (α-methylbenzyl) salicylic acid, 5- (α-methylbenzyl) salicylic acid, 3- (α, α-dimethylbenzyl) -salicylic acid, 4- (Α, α-dimethylbenzyl) -salicylic acid, 5- (α, α-dimethylbenzyl) -salicylic acid, 3,5-di (α-methylbenzyl) -salicylic acid, 3,5- (α, α-dimethylbenzyl) -Salicylic acid, 3- (α-methylbenzyl) -5- (α, α-dimethylbenzyl) salicylic acid, 3- (1 ', 3'-diphenylbutyl) salicylic acid, 5- (1', 3'-diphenylbutyl) Salicylic acid, 3- [α-methyl-4 ′-(α′-methylbenzyl) benzyl] salicylic acid, 5- [α-methyl-4 ′-(α′-methylbenzyl) benzyl] salicyl 3- (α-methylbenzyl) -5- (1 ′, 3′-biphenylbutyl) salicylic acid, 3- (1 ′, 3′-biphenylbutyl) -5- (α-methylbenzyl), 3-phenylsalicylic acid 5-phenylsalicylic acid, 3- (α, α-dimethylbenzyl) -5-phenylsalicylic acid, 3-phenyl-5- (α-methylbenzyl) salicylic acid, 5- (4′-methylphenyl) salicylic acid, 5- ( 4'-methoxyphenyl) salicylic acid, 5-fluorosalicylic acid, 3-chlorosalicylic acid, 4-chlorosalicylic acid, 5-chlorosalicylic acid, 5-bromosalicylic acid, 3-chloro-5- (α-methylbenzyl) salicylic acid, 3- ( α-methylbenzyl) -5-chlorosalicylic acid, 2-hydroxy-1-benzyl-3-naphthoic acid, 2-hydroxy-3- (α-me Rubenjiru) -1-naphthoic acid, 3-hydroxy-7-(alpha, alpha-dimethylbenzyl) -2-naphthoic acid and the like. These developers can be used alone or in combination of two or more. Among these, salicylic acid derivatives and polyvalent metal salts thereof can be particularly preferably used from the viewpoints of high color density, good water resistance, light resistance, and stability over time.

  Water-soluble starches such as oxidized starch, phosphorylated starch, hydroxyethyl etherified starch, urea phosphorylated starch, etc. as binders to be mixed in the paint; styrene / butadiene resin latex, acrylonitrile butadiene resin latex, styrene / acrylic One or more kinds of resin latexes such as resin latex, acrylic ester resin latex, and ethylene / vinyl acetate resin latex can be appropriately selected and used. Among these, water-soluble starches, particularly oxidized starch, and styrene / butadiene-based resin latex are particularly preferable from the viewpoint of improving color developability.

  The blending ratio of the pigment, the developer and the binder in the paint is preferably adjusted as appropriate so that the effects exhibited by the respective components are fully expressed.

  The blending amount of the developer is preferably 10 parts by mass or more, more preferably 12 parts by mass or more with respect to 100 parts by mass of the pigment, in order to obtain good color developability, and the developer is blended in a certain amount or more. However, there is an upper limit in color developability, and the cost increases when the amount of the developer is increased. From the viewpoint of suppressing the manufacturing cost, maintaining the strength of the developer layer, and scratching, the amount is 100 parts by weight of the pigment. It is preferably 25 parts by mass or less, more preferably 23 parts by mass or less.

  The amount of the binder should be 100 parts by weight with respect to 100 parts by weight of the pigment in order not to make it difficult to bind the developer on the base paper, or to prevent ink bleeding and imparting excellent color developability. 4 parts by mass or more, preferably 5 parts by mass or more, and in order to prevent the viscosity of the paint from becoming high and making it difficult to properly apply the paint to the base paper, On the other hand, it is preferably 30 parts by mass or less, more preferably 25 parts by mass or less.

In addition, while adjusting the blending amount within the above range, for example, the binder is adjusted so that the content in the developer layer is about 0.12 g / m ² or more. It is possible to eliminate the possibility that it becomes difficult to bind, and it becomes difficult to suppress deterioration of characters and images due to ink bleeding and to impart excellent color developability.

  In addition, by selecting water-soluble starch as a binder and optimizing the amount of binder contained in the developer layer, a sufficient color density can be obtained. Ink jet recording pressure-sensitive copying paper can be more practically used as middle and lower paper.

  The coating material used in the present embodiment may contain a small amount of a cationic resin or the like for fixing the ink during printing in the ink jet recording system to such an extent that the coating does not gel or aggregate. Examples of the cationic resin include dimethyldianylammonium chloride (DADMAC) polymer, allylamine hydrochloride polymer, diallylamine hydrochloride polymer, diallylamine hydrochloride-acrylamide copolymer, dimethyldianylammonium chloride-acrylamide copolymer. Dimethylamine-epichlorohydrin polycondensate, dimethylamine-ammonia-epichlorohydrin polycondensate, methacryloyloxyethyltrimethylammonium chloride polymer, dicyandiamide-diethylenetriamine polycondensate, dicyandiamide-formalin polycondensate, etc. 1 type (s) or 2 or more types can be mixed and used.

  Further, paints for forming the developer layer include, for example, sizing agents such as styrene / maleic resin, styrene / acrylic resin, alkyd resin, olefin resin, alkyl ketene dimer, higher fatty acid type, wax emulsion, petroleum Water-repellent agents such as resin-based emulsions and silicone-based emulsions can further improve the color density of pressure-sensitive copying developer sheets for ink-jet recording. For the purpose of obtaining a recorded image, the blending amount can be appropriately adjusted and used.

  Also, for example, various known water-resistant agents such as formalin, glyoxal, chrome light van, melamine, melamine formalin, polyamide epichlorohydrin resin, urea compound can be blended, and the blending amount is not particularly limited. It is preferable that it is about 0.1-10 mass parts with respect to 100 mass parts of total solid of a layer.

  Furthermore, conventionally known auxiliaries and the like can be appropriately added to the paint used in the present embodiment, in addition to the above-described components, as long as the characteristics are not impaired. Examples of such auxiliary agents include pigment dispersants, pH adjusters, water retention agents, thickeners, antifoaming agents, antiseptics, colorants, water resistance agents, wetting agents, fluorescent dyes, ultraviolet absorbers, and cationic polymers. Examples include electrolytes.

  For the preparation of the coating material, for example, a binder and a pigment, and further various other additives as necessary are mixed in a predetermined ratio, and then a developer is added to the obtained binder solution so as to be uniform at an appropriate temperature. It can be carried out by stirring and mixing so as to obtain a composition and dispersing the developer. For example, when the water-soluble starch is used as a binder, a binder solution is prepared by dissolving the binder made of the water-soluble starch in warm water at a predetermined temperature and then cooling to about 40 ° C. or less. It is preferable to add a predetermined amount of the developer to the binder solution and disperse it. By this, modification | denaturation of a developer and a binder, aggregation, etc. can fully be prevented and the surface strength of the developer layer formed on a base paper can further be raised.

For example, a blade coater, an air knife coater, a roll coater, a brush coater, a kiss coater, a squeeze coater, a curtain coater, a bar coater, a gravure coater, or a comma coater is applied to one main surface of the base paper with the paint obtained as described above. The developer layer is formed by coating at a coating amount of, for example, about 3 to 8 g / m ² so as to obtain a substantially uniform thickness by the coating method used, and drying.

  The pressure-sensitive copying color developing sheet thus obtained is a color developing sheet for ink-jet recording pressure-sensitive copying paper. In printing by the ink jet recording method, it is necessary to quickly absorb and dry ink jet ink droplets flying at high speed. Since a developer layer containing regenerated particles as a pigment is formed on such a pressure-sensitive copying developer sheet, printing suitability by such an ink jet recording system is excellent.

  The water absorption time when the ultrasonic transmission intensity reaches 50% in the measurement with an EST size meter (trade name: EST, manufactured by Emtec) of the pressure-sensitive copying developer sheet according to this embodiment is preferably 0.3. It is preferably at least 2 seconds, more preferably from 0.3 to 0.45 seconds, and particularly preferably from 0.32 to 0.43 seconds, from the viewpoint of securing the absorption drying property of the inkjet ink and the sharpness of the print information. If the water absorption time is less than 0.3 seconds, the water resistance as a pressure-sensitive copying developer sheet may be insufficient, and conversely if it exceeds 0.45 seconds, the ink-jet ink is developed. The fixability in the agent layer is low, and there is a possibility that the printed surface is smudged or smeared. In this embodiment, when the water absorption time is adjusted to 0.3 seconds or more, for example, when printing is performed at 100 m / min with a high-speed ink jet printer (product number: S6240J, manufactured by Uchida Hiroyuki). However, clear printing is possible, and the printed surface is not smudged or blurred.

  Inkjet printers in recent years are extremely fast, and pressure-sensitive copying paper requires more sizing (water absorption resistance) management, so it is sufficient to manage the paper strength in a conventional dry or wet state. Quality improvement cannot be said. In addition, it is not sufficient to measure only the sizing degree measurement method and the water drop method (drip water absorption degree method), which are current sizing degree management methods. In other words, the Cobb sizing measurement method and the drip water absorption method capture only static liquid absorption and serve as an index of water absorption, but the water absorption of the ink jet ink in the ink jet recording that is performed at high speed and performed instantaneously. It is not enough to observe the behavior.

  For this reason, it is necessary to perform quality control in a state close to actual printing conditions, and it is necessary to manage water absorption of paper instantaneously (that is, dynamically in a state where printing is actually performed). In view of the need for higher quality printing paper under such circumstances, in this embodiment, an instantaneous water absorption test value is obtained using an EST size meter. Measuring.

Further, in the pressure-sensitive copying color developing sheet according to the present embodiment, the wavelength optical contact ratio on the surface of the developer layer in the measurement with light of a wavelength of 0.5 μm under a pressure of 24.4 kg / cm ² by a microtopograph. It is preferably 8% or more. Such wavelength optical contact rate indicates the smoothness of the surface of the developer layer, and the developer is destroyed by destroying a microcapsule containing an oily substance in which an electron-donating organic color former is dissolved by physical pressure. It is necessary to evaluate under applied pressure because of the property of color development by reaction with. The wavelength optical contact ratio in the present embodiment refers to a value measured using a commercially available regular reflection smoothness meter (model name: Microtopograph, manufactured by Toyo Seiki Seisakusho Co., Ltd.).

  The microtopograph measures the wavelength optical contact ratio (%) between the prism under pressure and the surface to be measured, that is, the developer layer surface, from the ratio of the reflected light amount to the incident light amount. It means that the smoothness of the surface of the developer layer under pressure is better as the value of the target contact ratio is larger.

In the microtopograph used in the present embodiment, four wavelengths of 0.5 μm, 0.9 μm, 1.3 μm, and 1.7 μm are selected as specific wavelengths, and an optical contact rate F (λi) for each specific wavelength is obtained. Estimate the rate curve F (λ). Here, F (λ) is the ratio of the amount of light that penetrates into the paper at a depth corresponding to the wavelength with respect to the amount of incident light of a certain wavelength, and conversely, the amount of light that does not penetrate into the paper and reflects. Is integrated from 0 to ∞ with respect to the wavelength λ, a physical quantity proportional to the total capacity of the paper depressions or the average depth of the depressions is obtained. This is defined as Rp (Printing Roughness) represented by the following formula, and it can be determined that the larger the value, the rougher the surface and the worse the smoothness.
Rp = ∫ [1-F (λ)] dλ

In the present embodiment, the microtopograph is used, and the surface of the developer layer having a coating coating amount of, for example, 3 to 8 g / m ² is applied to one surface of the prism of the microtopograph under a pressure of 24.4 kg / cm ^2. The wavelength optical contact ratio of the surface of the developer layer when measured using light having a wavelength of 0.5 μm is preferably 8% or more, more preferably 10% or more, and particularly preferably 10-18. % Is preferable. When the wavelength optical contact ratio is less than 8%, the surface smoothness under pressure may not be sufficient, and good adhesion between the developer layers may not be obtained. On the other hand, when the wavelength optical contact ratio exceeds 18%, the surface smoothness under pressure is improved, and for example, the adhesion between the electron donating organic color former layer and the developer layer is improved, but the paper processing There is a risk that the contact area with the transport rolls in the apparatus or the printing machine becomes large, and the processing appropriateness such as inadvertent color development or double feeding may be deteriorated.

  As described above, the pressure-sensitive copying color developing sheet for ink-jet recording according to this embodiment does not cause bleeding or a decrease in image density when wet, and can provide a clear recorded image and is sufficient as pressure-sensitive copying paper. The color density can be maintained, and a pressure-sensitive copying paper suitable for an ink jet recording system can be constituted. Further, the developer layer formed on the pressure-sensitive copying developer sheet has a high surface strength and suppresses the occurrence of processing fog in the developer layer. Practicality as a lower sheet of pressure-sensitive copying paper for recording.

  As described above in the present specification, the pressure-sensitive copying developer sheet according to the present embodiment is composed of a base paper and a developer layer formed on one main surface thereof, and is usually pressure-sensitive copying paper. For example, the color developer layer generally the same as that provided on the upper sheet is provided on the other main surface opposite to the one main surface on which the developer layer of the base paper is formed. And can be used as medium paper for pressure-sensitive copying paper.

  Next, the pressure-sensitive copying developer sheet for ink-jet recording of the present invention will be described in more detail based on the following examples, but the present invention is not limited to these examples.

Production Examples 1 to 10 and Comparative Production Examples 1 to 4 (Production of regenerated particles)
As shown in Table 1, as a raw material, deinking floss (deinking floss obtained from a used paper processing process for producing used paper pulp, Production Examples 1 to 10) or papermaking sludge (mainly waste water discharged from the papermaking process) Using dehydrated sludge, Comparative Production Examples 1 to 4), a dehydration step, a drying step and a firing step were performed under the conditions shown in Table 1, and wet pulverization was performed to obtain regenerated particles (regenerated particles 1, 2, 4). To 10 and comparatively regenerated particles 1 to 4).

  Furthermore, in Production Example 3, the regenerated particles were added to and dispersed in a sodium silicate solution (water glass) to prepare a slurry. Then, while heating and stirring, the liquid temperature was maintained at about 85 ° C., and dilute sulfuric acid was added. A silica sol was produced. Subsequently, the pH of the reaction solution was adjusted to 8 to 11, and silica was deposited on the surface of the regenerated particles to obtain silica-coated regenerated particles (regenerated particles 3).

  About the obtained reproduction | regeneration particle | grains and a silica covering reproduction | regeneration particle | grain, content of calcium, silicon, and aluminum was calculated | required in oxide conversion, respectively, and the total content rate of calcium, silicon, and aluminum was computed. The results are shown in Table 2. The average particle size is also shown in Table 2. In addition, wire wear, productivity, quality stability and appearance were also examined. These results are also shown in Table 2.

  In addition, the various measured values shown to Tables 1-2 were measured with the following method.

(A) Average particle size of dried product after drying process (firing process inlet) X-ray microanalyzer (model number: EMAX2770, manufactured by Hitachi, Ltd./Horiba, Ltd.) at an acceleration voltage of 15 kV, black and white polaroid film Twenty X-ray images of the X-ray microanalyzer display were taken and measured at Polaroid (8.5 cm × 10.8 cm).

(A) Ratio of particles having a particle size of 355 to 2000 μm after the drying step (calcination step inlet) The mass ratio of dry matter particles having a particle size of more than 2000 μm is obtained with a 42 mesh sieve. The mass ratio was measured assuming a mass ratio of dried particles having a particle diameter of less than 355 μm.

(C) Content of calcium, silicon and aluminum in regenerated particles (as oxide)
Elemental analysis was performed with an X-ray microanalyzer (model number: E-MAX · S-2150, Hitachi, Ltd./Horiba, Ltd.). Moreover, the total content rate (calculated in terms of oxide) of calcium, silicon and aluminum was also calculated.

(D) Average particle diameter of regenerated particles 10 mg of a regenerated particle sample was added to 8 mL of a methanol solution and dispersed with an ultrasonic disperser (output: 80 W) for 3 minutes. This solution was measured with a Coulter counter particle size distribution measuring apparatus (TA-II type, manufactured by COULTER ELECTRONICS) using an aperture of 50 μm. However, for a 50 μm aperture that cannot be measured, a 200 μm aperture was used. Moreover, ISOTON II (trade name, manufactured by COULTER ELECTRONICS, 0.7% high-purity NaCl aqueous solution) was used as the electrolytic solution.

(E) Degree of wire wear Using a wear degree test apparatus (manufactured by Nippon Filcon Co., Ltd.), the degree of wear of the plastic wire was measured for 3 hours at a slurry concentration of 2% by mass.

(F) Productivity Each of the raw material dewatering efficiency, productivity, and electric power required for pulverization was evaluated in five stages, and evaluated based on the following evaluation criteria.
(Evaluation criteria)
A: All were highly evaluated and the balance was the best.
○: The evaluation may be averaged.
(Triangle | delta): There existed a problem in either the dehydration efficiency, productivity, and the electric power required for a grinding | pulverization.
X: Actual operation was difficult.

(G) Quality stability The degree of variation was measured for each item of whiteness, particle size, and production volume at a fixed time interval, ranked in ascending order of variation, and evaluated based on the following evaluation criteria.
(Evaluation criteria)
◎: Up to the top 3 ○: 4-6th △: 7-8th ×: 9th or less

(H) Appearance The color of the regenerated particles was visually observed and divided into white and gray.

  From the results shown in Table 2, it can be seen that all of the regenerated particles 1 to 10 have a low degree of wire wear and excellent productivity and quality stability. On the other hand, it can be seen that the comparatively regenerated particles 1 to 4 have a high degree of wire wear and are inferior in productivity and quality stability.

Preparation Examples 1-10 and Comparative Preparation Examples 1-7 (Preparation of paint)
As shown in Tables 3 to 4, light calcium carbonate (product number: TP-121-M7, manufactured by Nissei Kyoyoku Co., Ltd.), regenerated particles 1 to 10 or comparative regenerated particles 1 to 4, and silica (product) Name: Carplex 80D, manufactured by Shionogi Seiyaku Co., Ltd.), salicylic acid copolymer zinc salt as developer, oxidized starch (product number: MS3600, manufactured by Nippon Shokuhin Kako Co., Ltd.) and styrene-butadiene copolymer A combined latex (product number: LX407ST, manufactured by Nippon Zeon Co., Ltd., glass transition temperature: 0 ° C.) was prepared.

  20 parts by mass of 40% dispersion of zinc salicylic acid copolymer, 20% aqueous solution of oxidized starch in the amount shown in Tables 3-4, 100 parts by mass of pigment aqueous dispersion shown in Tables 3-4, styrene / butadiene 10 parts by mass of polymer latex was added and stirred and mixed at room temperature to obtain uniform paints 1 to 10 and comparative paints 1 to 7. In Comparative Example 2, 15 parts by mass of a quaternary ammonium salt copolymer was added as an additive to 100 parts by mass of the pigment.

Examples 1 to 10 and Comparative Examples 1 to 7 (Production of pressure-sensitive copying developer sheet)
Measured according to “basis weight measurement method” described in JIS P 8124 using 90 parts by mass of LBKP (hardwood kraft pulp) and 10 parts by weight of waste paper pulp (CSF of raw material pulp: 300 ml) as raw material pulp After coating the paints 1 to 10 or the comparative paints 1 to 7 using a blade coater so that the coating amount (solid content) is 5 g / m ² on one side with a basis weight of 40 g / m ² ) The film was heated and dried at 120 ° C. to 180 ° C. to form a developer layer having a thickness of about 2 to 12 μm to obtain a pressure-sensitive copying developer sheet.

  The physical properties of the obtained pressure-sensitive copying developer sheet were measured by the following methods. These results are shown in Table 5.

(A) Water absorption time for ultrasonic transmission intensity to reach 50% Using an EST size meter (trade name: EST, manufactured by Emtec), water absorption time for ultrasonic transmission intensity to reach 50% (in Table 5, “ EST ”).

(B) Wavelength optical contact ratio on the surface of the developer layer Using a microtopograph (registered trademark, manufactured by Toyo Seiki Seisakusho Co., Ltd.), color is developed with light having a wavelength of 0.5 μm under a pressure of 24.4 kg / cm ^2. The wavelength optical contact rate on the surface of the agent layer was measured.

  Next, the characteristics of the pressure-sensitive copying color developing sheets of Examples 1 to 10 and Comparative Examples 1 to 7 were examined based on the following Test Examples 1 to 8. The results are shown in Table 5.

Test Example 1 (ink bleeding)
Printer device (model number: BJ-455, manufactured by Canon Inc.) and Cytex ink (trade name: BK-1069, manufactured by Canon Inc.) are applied to the developer layer of the pressure-sensitive copying developer sheet. The barcode was printed using an inkjet recording method. The degree of bleeding of the printed image was visually confirmed and evaluated based on the following evaluation criteria.
(Evaluation criteria)
○: No blur is observed in the image.
X: Bleeding is observed in the image.

Test example 2 (ink density)
Printer device (model number: BJ-455, manufactured by Canon Inc.) and Cytex ink (trade name: BK-1069, manufactured by Canon Inc.) are applied to the developer layer of the pressure-sensitive copying developer sheet. The solid printing was performed by the ink jet recording method. After 5 seconds, the density of the solid print portion was measured with an ink densitometer (model number: RD915, manufactured by Macbeth Co.) and evaluated based on the following evaluation criteria.
(Evaluation criteria)
A: The ink density is 1.20 or more.
A: The ink density is 1.00 to 1.19.
X: The ink density is less than 1.00.

Test Example 3 (low temperature initial color developability)
Overlay the developer sheet for pressure-sensitive copying paper so that the coated surface faces the commercially available upper paper (the color developing layer containing the color former microcapsule composition is provided on one main surface of the base paper), It cooled for 1 hour on the conditions of temperature 5 degreeC. After this, under the same temperature condition, a print color was developed using a dot impact printer (model number: PC-PR201 / 65, manufactured by NEC Corporation), and the color density after 10 seconds of color development was measured with a Macbeth densitometer (model number: DM-620, manufactured by Dainippon Screen Mfg. Co., Ltd.). The larger the measured value, the higher the color density. If the color density is 0.4 or more under the above conditions, the low temperature initial color developability is good.

Test Example 4 (color density)
Subsequent to the low-temperature initial color development test of Test Example 3, the developed color developed sheets were transferred to room temperature (24 ° C.) conditions, and the color density after 24 hours was measured with the same Macbeth densitometer. did. In addition, it shows that color development density is so high that this measured value is large.

Test example 5 (surface strength)
Using an RI printing tester (model number: RI-2, manufactured by Ishikawajima Industrial Machinery Co., Ltd.), ink (trade name: Fine Ink [Picking Test (Red)) on the developer layer of the pressure-sensitive copying developer sheet , TV = 26], manufactured by Dainippon Ink & Chemicals, Inc., and the surface strength of the developer layer was evaluated based on the following evaluation criteria.
(Evaluation criteria)
○: No peeling is observed in the developer layer.
X: Peeling is observed in the developer layer.

Test Example 6 (Paint fluidity)
After pouring the paints (paints 1 to 10 and comparative paints 1 to 7) used in each example and comparative example into a predetermined container, the fluidity when tilted at a predetermined angle (about 45 degrees) is visually observed. It confirmed and evaluated based on the following evaluation criteria.
(Evaluation criteria)
○: The fluidity of the paint is appropriate and can be applied to the base paper without any problem.
X: The viscosity of the paint is high and the fluidity is unsuitable, and it is difficult to coat the base paper.

Test example 7 (manufacturing cost)
With respect to the paints (paints 1 to 10 and comparative paints 1 to 7) used in each example and comparative example, when 100 parts by weight of light calcium carbonate is used as a pigment to be blended in the paint (comparative examples 2 and 3). Evaluation was made based on the following evaluation criteria.
(Evaluation criteria)
○: Manufacturable at an inexpensive manufacturing cost.
Δ: Cost increases.
X: Significant cost increase.

Test Example 8 (Coating property)
In each of the examples and comparative examples, when paints (paints 1 to 10 and comparative paints 1 to 7) are applied with a blade coater, stratite, storyk, and scratches are generated, and gelation and solidification in paint preparation are performed. The situation was visually observed and evaluated based on the following evaluation criteria.
(Evaluation criteria)
○: Not at all.
Δ: Slightly generated.
X: Generated.

  From the results shown in Table 5, the pressure-sensitive copying color developing sheets of Examples 1 to 10 were all obtained at low cost, and the water absorption time for reaching an ultrasonic transmission intensity of 50% was 0.3 seconds or more. Long, wavelength optical contact ratio on the surface of the developer layer is as high as 8% or more, no ink bleeding, high ink density, excellent low temperature initial color developability, high color density thereafter, surface strength Therefore, it can be seen that the developer layer does not peel off after printing, the fluidity of the paint forming the developer layer is good and the coating property is excellent, and is suitable for the ink jet recording system.

  On the other hand, the pressure-sensitive copying color developing sheets of Comparative Examples 1 to 7 have physical properties such as a short water absorption time for the ultrasonic transmission intensity to reach 50% and a low wavelength optical contact rate on the surface of the developer layer. It is inferior. In addition, ink bleeding may occur, ink density, low temperature initial color developability and color density may be low, or surface strength may be low and the developer layer may be peeled off after printing. Furthermore, some of the paints forming the developer layer have poor fluidity and inferior coating properties, and have excellent physical properties and characteristics like the developer sheets for pressure-sensitive copying paper of Examples 1-10. Therefore, it can be seen that the ink jet recording method is not suitable.

The pressure-sensitive copying developer sheet for ink jet recording of the present invention can be suitably used for printing or printing by the ink jet recording method.

Claims (6)

A developer sheet provided with a developer layer on one main surface of the base paper and the base paper,
The developer layer is formed of a paint mainly containing a pigment, a developer and a binder,
Characterized in that it contains a play particles deinking froth as the pigment as the main raw material used more than 50% of the raw material, the ink jet recording pressure-sensitive copying color-developing sheet.   The pressure-sensitive copying developer sheet for ink-jet recording according to claim 1, wherein the ratio of regenerated particles in the total amount of pigment is 10 to 50% by mass.   Regenerated particles are obtained through dehydration process, drying process, firing process and pulverization process using deinked floss as the main raw material, and calcium, silicon and aluminum are converted into oxides in terms of oxides by elemental analysis: calcium: silicon: 2. The inkjet according to claim 1, wherein the regenerated particles are contained in a mass ratio of aluminum = 30 to 82: 9 to 35: 9 to 35, and the total content ratio of the calcium, silicon, and aluminum is 90 mass% or more. Pressure-sensitive copying developer sheet for recording.   The pressure-sensitive copying developer sheet for ink-jet recording according to claim 1, wherein the regenerated particles are silica-coated regenerated particles whose surfaces are coated with silica.   The pressure-sensitive copying color developing sheet for ink-jet recording according to claim 1, wherein the water absorption time for ultrasonic transmission intensity to reach 50% in the measurement with an EST size meter is 0.3 seconds or more. ^2. The inkjet recording according to claim 1, wherein the wavelength optical contact ratio on the surface of the developer layer is 8% or more when measured with light having a wavelength of 0.5 μm under a pressure of 24.4 kg / cm ² by a microtopograph. Pressure sensitive color developing sheet.