JP2908148B2 - Pressure-sensitive recording sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive recording sheet in which the color density varies depending on the applied pressure.

[0002]

2. Description of the Related Art A pressure-sensitive recording sheet is known in which a color developing agent is applied to a sheet-like support, and a microencapsulated color developing agent is applied thereon (for example, Japanese Patent Publication No. 57-24852).
No. 59-16654, etc.).

In this pressure-sensitive recording sheet, if water adheres to the color former, the pressure cannot be measured accurately. Therefore, it has been considered to cover this with a waterproof transparent sheet. For example, in Japanese Utility Model Publication No. 45-8166, a waterproof layer is formed on one surface of a transparent paper (support) by polyethylene laminating or coating a vinylidene chloride copolymer emulsion.
Microcapsules are applied to the other surface of the transparent paper, an envelope is formed with the microcapsule application surface inside, and an appropriate number of middle papers, lower papers, etc. coated with a developer are accommodated therein,
A seal around the envelope with an adhesive is shown.

Further, Japanese Patent Application Laid-Open Nos.
No. 24314 discloses that a protective layer is laminated on a recording sheet surface to impart water resistance.

[0005]

2. Description of the Related Art A waterproof layer is provided on one side of transparent paper.
In the method of forming an envelope by forming a microcapsule layer on the other surface and sealing the periphery of the envelope, the microcapsule layer is sandwiched between the two transparent papers around the envelope together with the adhesive. Become. For this reason, the adhesion is incomplete and the reliability of the sealing is deteriorated. Further, there is also a problem that adhesion between the middle paper or lower paper stored inside and the transparent paper is poor, and the paper is peeled off during use.

On the other hand, when a protective layer is laminated on a recording sheet, the recording sheet is heated in the laminating step, so that there is a problem that the recording sheet is deteriorated by heat and its color developing ability is reduced.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has an advantage that the recording sheet is completely sealed, has high reliability of water resistance, and peels off the recording sheet from the waterproof layer during use. It is another object of the present invention to provide a pressure-sensitive recording sheet which does not cause deterioration due to heating.

[0008]

According to the present invention, it is an object of the present invention to provide a color-developing agent in which a color developing agent is coated on one surface of a sheet-shaped synthetic resin support, and the micro-encapsulated color forming agent is further coated on the color developing agent coated layer. In the pressure-sensitive recording sheet coated with, a synthetic resin back waterproof layer adhered to the other surface of the support by an adhesive,
A pressure-sensitive layer comprising: a transparent synthetic resin front waterproof layer directly covering the coloring agent coating layer, wherein the back waterproof layer and the front waterproof layer are liquid-tightly bonded along the outer periphery of the support. Achieved by recording sheets.

[0009]

1 is a partial sectional view of an embodiment of the present invention, FIG.
FIG. 6 is a graph showing a change in color density with respect to pressure. In this figure, reference numeral 10 denotes a sheet-shaped synthetic resin support,
For example, a PET (polyethylene terephthalate) film having a thickness of 25 μm is used. Reference numeral 12 denotes a developer coating layer, which is formed by applying a solution obtained by dispersing an acid clay (montmorillonite) sulfuric acid-treated product in water containing caustic soda to one surface (surface) of the support 10 and drying the solution. is there.

Reference numeral 14 denotes a color-developing agent coating layer formed on the color-developing agent coating layer 12, which is formed by dissolving a color developing agent such as 1-phenyl-1-xylylethane in oil and microencapsulating it. is there. Here, the microcapsules are adjusted to various strengths, and the microcapsules to be destroyed change according to the pressure. When the microcapsules are destroyed by the pressure, the color developing agent therein is absorbed by the color developing agent together with the oil to form a color. The color density increases with increasing pressure. FIG. 2 shows the change of the concentration D with respect to the change of the pressure P.

Reference numeral 16 denotes a back waterproof layer, which is formed of the same PET film as the support 10, for example, a 16 μm transparent film. An adhesive type paste is applied to one surface of the back waterproof layer 16 to form an adhesive layer 18. The back waterproof layer 16 is adhered to the back surface of the support 10 (the surface opposite to the color developer layer 12) by the adhesive layer 18.

Reference numeral 20 denotes a front waterproof layer, which is formed of a transparent PET film having a thickness of 16 μm similarly to the back waterproof layer 16. The front waterproof layer 20 is overlaid on the color forming agent coating layer 14, and is adhered to the adhesive layer 18 of the back waterproof layer 16 along the outer periphery of the support 10. In this case, it is desirable that the pressure between the waterproof layers 16 and 20 be sufficiently reduced and evacuated.

Thus, the support 10 and the developer coating layer 12
And a pressure-sensitive recording sheet formed by the color-forming agent coating layer 14,
Since the back waterproof layer 16 and the front waterproof layer 20 are hermetically sealed, the water resistance is improved and the reliability is increased. One waterproof layer 1
Since 6 is adhered to the back surface of the support 10, the back waterproof layer 16 does not peel off or move with respect to the support 10. Therefore, the front waterproof layer 20, the periphery of which is adhesively fixed to the back waterproof layer 16, does not move with respect to the support 10.

[0014]

According to the first aspect of the present invention, as described above, the back waterproof layer is adhered to the back surface of the support, that is, the surface opposite to the color developer coating layer, by the adhesive layer, and the color developing agent coating layer is formed on a transparent surface. Since it is directly covered with the waterproof layer and both waterproof layers are adhered in a liquid-tight manner along the periphery of the support, the sealing is complete and the reliability of water resistance is improved. Further, since the back waterproof layer is adhered and fixed to the support, the movement of the front waterproof layer adhered to the back waterproof layer is restricted, and the back waterproof layer is hardly peeled off from the recording sheet. Furthermore, since the waterproof layer is fixed with an adhesive, there is no need to heat the sheet as in the case of laminating, and the deterioration of the recording sheet due to heat,
There is no danger of deteriorating color development.

The support and the waterproof layer on the back and front sides are made of PE
It is desirable to form with a T film, and to apply an adhesive layer to a back waterproof layer (claims 2 and 3).

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of the present invention.

FIG. 2 is a graph showing a change characteristic of a density D with respect to a pressure P of a pressure-sensitive recording sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Support body 12 Developer application layer 14 Color former application layer 16 Back waterproof layer 18 Adhesive layer 20 Front waterproof layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41M 5/124-5/165 G01L 5/00

Claims (3)

(57) [Claims] 1. A pressure-sensitive recording sheet comprising a sheet-shaped synthetic resin support, a developer applied to one surface of the support, and a microencapsulated color former applied on the developer coating layer. A back waterproof layer made of a synthetic resin adhered to the other surface of the support by an adhesive, and a front waterproof layer made of a transparent synthetic resin that directly covers the colorant application layer, wherein the back waterproof layer and the front waterproof layer are provided. Characterized by being adhered in a liquid-tight manner along the outer periphery of the support. 2. The pressure-sensitive recording sheet according to claim 1, wherein the support is a polyethylene terephthalate film. 3. The pressure-sensitive recording sheet according to claim 1, wherein the front waterproof layer and the back waterproof layer are polyethylene terephthalate films, and the adhesive is applied to the entire back waterproof layer.