JP3144822B2 - Recording sheet and recorded matter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording sheet and a recorded matter.

[0002]

2. Description of the Related Art In recent years, an overhead projector (hereinafter, referred to as an OHP) has been often used in a conference or the like instead of a conventional slide. In such a case, an image is formed on a transparent recording sheet by handwriting or using a printer such as an electrostatic transfer system or an inkjet system.

[0003] Conventionally, as an OHP recording sheet, a plastic sheet such as polyethylene terephthalate, or a sheet whose surface is processed to easily adsorb a dye is used.

[0004]

Since these OHP recording sheets use a plastic sheet as a base material, they are easily charged and are often caught in a machine when the recording sheet is automatically fed by a machine. . Furthermore, the sheet may become sticky or dirty due to oil adhering from the conveying roller, the heating roller, or the like.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a recording sheet which is suitable for a machine and is capable of obtaining a recorded matter having high color density and high durability.

[0006]

According to the present invention, there is provided a recording sheet having a dye adsorbing layer provided on a base material, a porous alumina hydrate layer provided on the opposite side of the surface of the base material provided with the dye adsorbing layer. And the porous alumina hydrate layer comprises alumina
An object of the present invention is to provide a recording sheet containing a binder in an amount of 5 to 50% by weight based on a hydrate .

In the present invention, the porous alumina hydrate layer on the opposite side of the surface on which the dye-adsorbing layer is provided imparts appropriate electric conductivity and oil absorption to the sheet.

As the porous alumina hydrate on the side opposite to the surface on which the dye adsorption layer is provided, pseudo-boehmite (AlO (OH)) is preferable. The porous alumina hydrate layer has a pore structure substantially composed of pores having a radius of 10 to 100 mm and a pore volume of 0.
When it is 3 to 1.0 cc / g, it is preferable because it has sufficient absorbency and transparency. At this time, if the substrate and the dye adsorption layer are transparent, a transparent recording sheet can be obtained.

[0009] In addition to these physical properties, the average pore radius of the alumina hydrate layer is a 15～50A ± the average pore radius
The case where the volume of the pores having a radius of 10 ° is 45% or more of the total pore volume is particularly preferable from the viewpoint of compatibility between absorbency and transparency. The average pore radius is 15-30Å, and the volume of pores having a radius of ± 10Å of the average pore radius is the total pore volume.
More preferably, it is 55% or more. The measurement of the pore radius distribution in the present invention is based on the nitrogen adsorption / desorption method.

The thickness of the alumina hydrate layer on the side opposite to the surface on which the dye-adsorbing layer is provided is appropriately selected according to the specifications of each printer and the like, but is preferably 0.5 to 50 μm. If the thickness of the alumina hydrate layer is less than 0.5 μm, the effect of the present invention may not be sufficiently exhibited, and
If it exceeds m, the transparency of the alumina hydrate layer may be impaired or the strength of the layer may be reduced, so that each is not preferred.

Means for providing an alumina hydrate layer on a substrate include, for example, a slurry obtained by adding a binder to alumina hydrate, and a roll coater, an air knife coater, a blade coater, a rod coater, a bar coater, a comma coater, or the like. And a method of applying and drying.

As the binder, there can be used organic substances such as starch and modified products thereof, polyvinyl alcohol and modified products thereof, SBR latex, NBR latex, carboxymethylcellulose, hydroxymethylcellulose and polyvinylpyrrolidone. The amount of the binder used is 5 to 50% by weight of the alumina hydrate . If the amount of the binder is less than 5% by weight, the strength of the alumina hydrate layer may be insufficient, and conversely, 50% by weight.
If exceeding, the Ru respectively unsuitable der the absorption property may become insufficient.

In the present invention, the substrate is not particularly limited, and various substrates can be used. Specifically, various plastics or papers such as polyester resins such as polyethylene terephthalate and polyester diacetate, polycarbonate resins, and fluorine resins such as ETFE can be preferably used. OHP
For a recording sheet, the substrate needs to be transparent, but an opaque substrate can also be used. Further, for the purpose of improving the adhesive strength of the alumina hydrate layer, a corona discharge treatment, an undercoat, or the like can be performed.

[0014] In the present invention, the dye adsorption layer yet preferably a porous alumina hydrate. In particular, dyes are well absorbed and fixed,
Pseudo-boehmite (AlO (OH)
Is preferred.

The alumina hydrate layer of the dye-adsorbing layer has a pore structure substantially composed of pores having a radius of 10 to 100 mm and a pore volume of 0.3 to 1.0 cc / g. It is preferable because it has excellent absorbability and the alumina hydrate layer is also transparent . In addition to these physical properties, the average pore radius of the alumina hydrate layer is a 15~50Å its pore volume having a radius of mean pore radius ± 10 Å is 45% or more of the total pore volume Is particularly preferable from the viewpoint of achieving both fixing property and transparency. The average pore radius is 15-30Å and the volume of pores having a radius of ± 10Å of the average pore radius is 55% of the total pore volume
The case where the above is more preferable is more preferable.

The thickness of the dye-adsorbing layer is appropriately selected depending on the specifications of each printer and the like, but is preferably 0.5 to 50 μm. If the thickness of the dye-adsorbing layer is less than 0.5 μm, the dye may not be sufficiently adsorbed.If it exceeds 50 μm, the transparency of the dye-adsorbing layer may be impaired or the strength of the layer may be reduced. , Respectively, is not preferred.

As the means for providing dye adsorption on the substrate, the same method as that for the back surface is preferably used.

The recording sheet of the present invention can be suitably used for a transparent sheet such as an OHP recording sheet. In addition, the opaque material has the effect of the present invention. When a transparent substrate is used and a transparent porous alumina hydrate layer is provided on the opposite side of the surface provided with the dye-adsorbing layer, an image of the dye-adsorbing layer can be observed through the transparent substrate. .

[0019]

【Example】

Example 1 A glass reactor having a capacity of 2000 cc was charged with 900 g of water and 676 g of isopropyl alcohol, and heated to 75 ° C. by a mantle heater. While stirring, add 306 g of aluminum isopropoxide, and adjust the liquid temperature to 75 to 78 ° C.
For 5 hours. Then 95
The temperature was increased to 9 ° C., 9 g of acetic acid was added, and the mixture was peptized by keeping the temperature at 75 to 78 ° C. for 48 hours. The liquid was further concentrated to 900 g to obtain a white sol. The dried product of this sol was pseudo-boehmite.

[0020] In addition port <br/> Ribi alkenyl alcohol 1 part by weight (solids) in the alumina sol 5 parts by weight (solids), was further added with water to prepare a solid content of about 10% of the slurry. The slurry was applied onto a sheet substrate made of polyethylene terephthalate (thickness: 100 μm) that had been subjected to a corona discharge treatment using a bar coater so that the layer thickness when dried was 10 μm, and dried. Next, on the opposite surface, the above-mentioned alumina sol was applied in a similar manner so that the film thickness when dried was 5 μm, and dried to obtain a recording sheet. The pore characteristics of the alumina hydrate layer obtained on the substrate,
The average pore radius was 20 mm, and the pore volume with a pore radius of 10 to 30 mm was 60% of the total pore volume.

With respect to the recording sheet, an electrostatic transfer type electrophotographic digital copying machine (Pixel DI manufactured by Canon Inc.)
O) to print red, yellow and blue solid pattern
Was evaluated. At this time, multiple recording sheets are continuously
Print, and hold the recording sheet after printing
did. After printing , another recording sheet pattern that overlaps with the back side of the printing surface of the recording sheet
When observing the part that was in contact with the printed part,
There was no sticky feeling at all. Also, allowed to remain superposed after printing recording sheet <br/>, after 3 hours, was overlaid Align
When the recording sheet was peeled off, it could be easily peeled off. There was no stickiness in the printed part.

[0022]

According to the present invention, the recording sheet of the present invention has a reduced chargeability and can be less entangled in a machine.
Further, since the oil adhering from the transport roller, the heating roller or the like is adsorbed by this layer, the sheet is not sticky or dirty. When that had been piled up recording sheet,
Recording sheet to each other is, it does not become peeled off is difficult. Furthermore, in the case of a printing method using an ink containing a large amount of solvent, such as an ink jet printer, the alumina hydrate layer on the side opposite to the printing surface in the overlapping portion absorbs the solvent, so that the printing is continuously performed. not stick even superposed immediately after the printed recording sheet Te. For this reason, a recorded matter continuously printed by the machine can be stably obtained.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-62-233291 (JP, A) JP-A-64-78877 (JP, A) JP-A-4-230768 (JP, A) JP-A-4- 267180 (JP, A) JP-A-4-298380 (JP, A) JP-A-4-298381 (JP, A) JP-A-4-320288 (JP, A) Japanese Utility Model Application No. Sho 60-114762 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B41M 5/00 B41M 5/38-5/40

Claims (3)

(57) [Claims] 1. A recording sheet having a dye-adsorbing layer provided on a substrate, the recording sheet having a dye-adsorbing layer provided on the opposite side of the substrate.
A porous alumina hydrate layer formed, and the porous Al
Mina hydrate layer has binder for alumina hydrate
Is 5 to 50% by weight . 2. A dye adsorption layer is a porous alumina hydrate, a recording sheet of claim 1, wherein. 3. A recording sheet according to claim 1 or claim 2, wherein, in the dye adsorption layer, recorded matter dye is adsorbed.