JPS6337984A - Color developer sheet - Google Patents

Abstract

PURPOSE:To improve a color forming performance such as light resistance and fade resistance with time after color forming and simplify a process, by a method wherein a sheet-form molded piece of a mixture of an olefin resin, a color developer, a tackifier, and a dye- adsorptive inorganic matter is bonded to a substrate as one piece. CONSTITUTION:A sheet-form molded piece of a mixture of an olefin resin such as polyethylene, polypropylene, and the copolymer or blended substance of these materials, a color developer such as novolak-type phenol resin, a tackifier, and a dye-adsorptive inorganic matter is bonded to a substrate as one piece. The color developer is preferably used 1.0-10.0 parts by weight to 100 parts, by weight of the olefin resin. The tackifier accelerating the color forming reaction of a leuco dye with the color developer is suitably used 20-150 parts by weight to 100 parts by weight of the olefin resin. The addition of the inorganic matter results in the adsorption and fixing of the color forming dye to the inorganic matter, thereby improving the blurring and decoloring of a colored image with time. The inorganic matter is desirably added 5-50 parts by weight to 100 parts by weight of the olefin resin. The construction, in which the sheet-form molded piece of the developer-containing resin is previously formed and bonded to the substrate as one piece, simplifies a process and eliminates the possibility that a solvent gas induces working-environment pollution, fire, and explosion.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention relates to a new color developer sheet, and more specifically, a color developer sheet formed by bonding a sheet-like molded product of a color developer-containing resin and a substrate. It is related to.

``Prior art'' ``Problems to be solved by the invention'' Nocicarbon paper is a so-called transfer type paper in which color former microcapsules and a color developer are coated on separate sheets of paper, and two types in which both agents are coated on the surface of the paper in two layers. It is roughly divided into self-contained type, which is applied by layering or mixing. These coating methods involve coating paper with a water or solvent-based liquid, which not only poses problems in the working environment, but also poses a risk of fire or explosion, and also requires a drying process. The process becomes complicated and requires a large amount of energy.

For example, a method to solve this problem is
-7917. This method is a method in which a solidified hot-melt coating composition is applied onto paper by a coating method such as roll or knife coating, or a printing method such as gravure.
The coating process is not necessarily easy, and it also has the disadvantage of requiring a large amount of color developer.

Therefore, in order to eliminate the above-mentioned drawbacks, the present inventors first proposed a color developer sheet that is formed by bonding and integrating a sheet-like molded product made of a mixture of an olefin resin and a color developer with a base material. (Japanese Patent Publication No. 148094/1983).

The developer sheet described above solved the above drawbacks and improved the performance (water resistance, oil resistance) of the separate type pressure-sensitive paper, but the light resistance after color development and the resistance to fading over time are not necessarily satisfied. It wasn't in the right condition.

``Means for Solving the Problems'' The present invention has been made based on the above-mentioned circumstances and as a result of intensive research, it has been found that tackifiers and dye-adsorbing inorganic substances have a remarkable effect on improving coloring performance such as light resistance after coloring and resistance to fading over time. know what to show,
This completes the present invention.

That is, the present invention includes a color developer sheet in which a sheet-like molded product made of a mixture of an olefin resin, a color developer, a tackifier, and a dye-adsorbing inorganic substance is bonded and integrated with a base material.

As the olefin resin used in the present invention, polyethylene, polypropylene, copolymers or blends thereof, etc. are suitable. By adding an olefin resin containing functional groups to a part of the olefin resin,
Color development performance may be further improved. Addition of the olefin resin containing a functional group promotes penetration of the leuco dye-containing capsule oil into the color developer sheet, and is effective in improving color development speed and color density. In addition, among the olefin resins containing functional groups, which have the effect of improving adhesion when bonding and integrating with a base material, ethylene/methyl methacrylate copolymer and ethylene/ethyl acrylate are preferred. These include copolymers, ethylene/acrylic acid copolymers, ethylene/methacrylic acid copolymers, etc. The proportion of the functional groups is preferably 2% by weight to 30% by weight, based on 100 parts by weight of the entire resin including the olefin resin. If it is less than 2% by weight, there is no dyeing performance improvement effect, and 3011
When the amount exceeds %, the coloring dye permeates and diffuses into the resin after color development, resulting in a loss of sharpness of the color image and a large decrease in color density over time.

The color developer used in the present invention is not particularly limited; for example, novola 7-type phenolic resin, 2°2-bis(4'
-oxyphenyl)propane (bisphenol A), 4
．． 4'-sec-butylidene diphenol (bisphenol B), zinc m- or P-hydroxybenzoate, zinc salicylate, zinc 3-tert-butylsalicylate, 3.
All known metal salts of aromatic carboxylic acids such as zinc 5-ditertiary butylsalicylate, zinc 3-phenylsalicylate, zinc 2-hydroxy-3-naphthoate, etc. can be used, but in particular, 3,5-ditertiary Zinc butylsalicylate has excellent coloring performance and is suitable.

The mixing ratio of olefin resin and color developer cannot be specified depending on the type of olefin resin, type of color developer, degree of color development, etc., but for 100 parts by weight of olefin resin,
The color developer is 1.0 to 10.0 parts by weight, more preferably 5 to 10.0 parts by weight.
It is 8 parts by weight. If it exceeds 10.0 parts by weight, it will be difficult to obtain a sheet-like molded product by extrusion molding, while if it is less than 1.0 parts by weight, color development will be insufficient.

All known tackifiers can be used as the tackifier used in the present invention, but those that are easily soluble in the capsule oil of the upper paper and do not inhibit the coloring reaction are particularly preferred. Preferred examples include hydrogenated terpene resins and alicyclic saturated hydrocarbon resins. The effects of the tackifier are thought to be to promote the color-forming reaction between the leuco dye and the color developer, and to generate minute cracks on the surface of the color developer sheet when pressurized, thereby expanding the colored area inward. The addition ratio of tackifier depends on the type of tackifier, but when the olefin resin is 100 parts by weight, it is 20 to 150 parts by weight.
Parts by weight are preferred. If the amount is less than 20 parts by weight, no improvement in color development will be observed, and if it exceeds 150 parts by weight, the melt viscosity of the entire mixture will become too low, causing problems in processing.

As the inorganic substance used in the present invention, any inorganic substance used as a resin filler or a color developer can be used. For example, silica, calcium carbonate, mica, talc, titanium oxide, zeolite, bentonite, barium sulfate, glass powder, activated clay, acid clay,
Klee et al.

The first purpose of using the inorganic material is to improve the surface roughening effect by improving the hardness of the surface of the color developer sheet, and the inorganic material itself also contributes to the surface roughening and improves the color density. The second purpose of use is to prevent color-forming dyes from penetrating and diffusing into the developer sheet.Color-forming dyes move and diffuse in the olefin resin over time, causing the colored image to lose its sharpness and become blurred. However, by adding the above-mentioned inorganic substance, the colored dye is adsorbed and fixed to the inorganic substance, and the blurring and discoloration of the colored image over time are improved.The characteristics of the inorganic substance used in the present invention are as follows. Particularly suitable inorganic substances that are neutral or acidic and have a large specific surface area include silica/alumina compounds, silica, silica balloons, zeolites,
Activated clay etc.

The blending ratio of the inorganic substance is preferably 5 to 50 parts by weight per 100 parts by weight of the olefin resin; if it is less than 5 parts by weight, the effect will be insufficient, while if it exceeds 50 parts by weight, processability will deteriorate. In the present invention, where film formation is difficult, known coloring aids and stabilizers may be added as necessary. The amount of these additives may be generally 2 to 10 parts by weight.

Further, it is a preferable embodiment to add an opacifying agent that increases the contrast with respect to color development to the mixture of the present invention from the viewpoint of making the pressure-sensitive color image easier to see.

As such an opacifying agent, Tie, CaCO, barium sulfate, plastic fine particles, etc. can be used, but rutile titanium oxide is particularly preferred.The amount of the opacifying agent added is, for example, If it exceeds 20 parts by weight, it becomes difficult to make the color developer sheet thin, and if it is less than 1 part by weight, sufficient opacity cannot be achieved.

Examples of the base material in the present invention include paper, cloth, nonwoven fabric, cellophane, synthetic resin film, metal foil, and a laminate of a synthetic resin film and metal foil.

The sheet-shaped molded product of the above mixture is obtained by roll molding, extrusion molding, etc., and the molded product and the base material are bonded and integrated by adhesion, welding, fusion, etc., but extrusion lamination method is particularly preferred. It is.

Note that in the present invention, heat treatment is performed as necessary.

The heat treatment has the advantage that the color developer is transferred and unevenly distributed on the surface of the sheet-like molded product made of the mixture of the olefin resin and the color developer, and therefore a desired coloring effect can be obtained with a small amount of the color developer.

It is desirable to apply corona treatment to the color developer sheet of the present invention. By applying corona treatment, the wettability and adhesion of the color developer sheet surface are improved, and when color former coated paper is layered and pressure-sensitive coloring is performed. Transfer of color developer to color former coated paper is prevented. The corona treatment is the same as the corona treatment commonly used to improve the surface wettability and adhesion of resin films, paper, etc., and is applied at a rate of 50 to 200 w/n? processing is sufficient.

The color developer sheet in the present invention is preferably subjected to surface roughening treatment at the same time as sheet-forming or after molding, and the surface area of the color developer sheet is increased by the roughening treatment,
Improves the apparent color density and improves the wetting of capsule oil. Furthermore, after color development, it has the effect of preventing the written information from becoming unclear due to friction.

The uneven processing can be performed, for example, by passing the extruded color developer sheet through a cooling roll with a matte surface when it is cooled and solidified, by sanding the surface before heat treatment, or by sanding the surface before heat treatment (C1 heat treatment). Preferred methods include bonding a film whose surface has been roughened in advance to the surface of a color developer sheet, removing the film after heat treatment, and transferring the rough surface of the film to the surface of the color developer sheet. Yes. Among the above methods, (
♂) is particularly suitable because it can be carried out simultaneously with the production of the color developer sheet and is simple, and let also has the advantage that it can be carried out simultaneously with heat treatment depending on the temperature employed.

"Examples" The present invention will be explained in more detail by way of Examples below.
The present invention is not limited in any way by these.

Example 1 As a polyolefin resin, low density polyethylene "Mirason M-10P (Ml-5.0g/l 0 min, density-
0,917g/cd) J (manufactured by Mitsui Petrochemical Industries)
50 parts by weight, ethylene/ethyl acrylate copolymer resin rNUc-657 as functional group-containing polyolefin resin
0J (MI=20g/10min・Density-0,943g
/j, containing 25% ethyl acrylate) (manufactured by Nippon Unicar Co., Ltd.) 50 parts by weight, natural zeolite [Jilton LP-75J (Mizusawa Chemical Industry type) 15 parts by weight as an inorganic substance, hydrogenated terpene resin "Clearon P" as a tackifier -1
25'' (manufactured by Yasuyu Kogyo Co., Ltd.) and 50 parts by weight, the mixture was melt-mixed using a screw extruder (vent type, diameter 4 Qw, die exit temperature 160° C.), and pelletized using a pelletizer.

Add 3.5- to the pelletized mixture as a color developer.
Zinc ditertiary butylsalicylate rGs-1” (
Sanko Kagaku *> 8 parts by weight, and 2 parts by weight of zinc 2-ethylhexanoate and 5 parts by weight of zinc stearate as coloring aids.
Adding 3 parts by weight of rutile titanium oxide as an opacifying agent,
After tri-blending, the mixture was melt-mixed using the screw extruder and pelletized using a pelletizer. After drying the pellets in a hopper dryer at 50°C for 2 hours, a T-die extruder (diameter 4Qm, T-die outlet temperature 170°C
) and extruded into a sheet (thickness: 20 μm).
A color developer sheet was obtained by pressure lamination on the polyethylene laminate surface of a bleached kraft (60 g/rrf laminated sheet) with a thickness of .

Example 2 Ethylene/methyl methacrylate copolymer resin “Acrift W” (-4
01Ml-20.0g/10min, density 0.94g/cj
In addition to using 50 parts by weight of J (manufactured by Sumitomo Chemical Industries),
A color developer sheet was obtained by the same processing operation as in Example 1.

Example 3 A color developer sheet was obtained by the same processing operations as in Example 1, except that the functional group-containing polyolefin resin was not used and the low density polyethylene resin was used in an amount of 100 parts by weight.

Comparative Example 1 Without using functional group-containing polyolefin resin and inorganic materials,
A color developer sheet was obtained by the same processing operations as in Example 1, except that the low density polyethylene resin was used in an amount of 100 parts by weight.

Comparative Example 2 A color developer sheet was obtained by the same processing operations as in Example 1, except that the functional group-containing polyolefin resin and the tackifier were not used, and the low-density polyethylene resin was 100 parts by weight.

Comparative Example 3 For comparison of coloring performance, commercially available separate type pressure-sensitive Gishi paper (manufactured by ±lI!181 paper) was used.

Color development evaluation: Examples 1 to 3, Comparative Examples 1.2, and Comparative Example 1 (commercially available lower paper) were coated with commercially available separate-type pressure-sensitive paper on the developer side.
NW40TJ (Jujo Paper YJ) was overlapped and pressure sensitive coloring was performed by applying pressure with a ballpoint pen.

The color density was compared 5 minutes after color development, and the results are shown in Table 1. The colored products were exposed to sunlight for 6 hours x 2 times = 12 hours) and the residual density was compared. Table 1 shows the results. Furthermore, in order to observe the change in color density over time, as an accelerated test, the samples were placed in a constant temperature bath (70° C., 65% RH) for one week and the densities were compared, and the results are shown in Table 1.

In the results in Table 1, it can be seen from Example 3 and Comparative Example 1 that the addition of inorganic substances prevents changes over time. Next, from Example 3 and Comparative Example 2, the addition of tackifier improves the color density. I understand. Furthermore, Example 1.2 and Example 3
Therefore, if a functional group-containing polyolefin resin is used,
It is understood that the color density increases and the decrease in color density due to the light fastness test and accelerated aging test is reduced.

Further, although commercially available paper sheets are easily damaged by external forces such as friction when wet, the color developer sheet according to the present invention is not easily damaged because it is mainly made of synthetic resin.

"Action""Effects of the Invention" As seen above, the present invention can provide a color developer sheet with significantly improved coloring performance. In addition, according to the present invention, a sheet-like molded product containing a color developer is made in advance and this and the base material are bonded and integrated, so the process is simpler than that of conventional coating methods. In particular, if the extrusion lamination method is used, it is possible to produce sheet-shaped products without the need for a drying process like with water-based or solvent-based liquids, and without the risk of contaminating the working environment due to solvent gas, fire, or explosion. It is extremely efficient because it can be integrated and bonded to the base material all at once.

・、□・・１１．、・、1 Wa procedure? l1Ii, inτtsubo July 1988 270 1986 Patent Application No. 181646 2 Name of the invention Color Developer Sheet 3 Relationship with the case: Patent applicant Address 4-13i18 Anritsu, Suminoe-ku, Osaka City Name: Goyo Shiko Co., Ltd. Representative Director: rf, Kojibe Se 4, Agent address: 3-2-4-5 Nishitenma, Kita-ku, Osaka, Subject of amendment: Column 6 of At Km Description of the Invention J, Amendment Contents (1) On page 7, at the beginning of the second line, insert "Magnesila silicate J." after "clay".

(2) Page 7, line 12, “…improved.”

'The third purpose of use is to improve the color density when an inorganic color developer is used as a dye-adsorbing inorganic substance. For example, magnesium silicate or silica-alumina compounds are used. ” is inserted.

(3) In the 10th column, line 10, between "method" and "etc.", insert "(d) Method of extruding and stretching a 17-RF colorant sheet into a film".

that's all

Claims (1)

[Scope of Claims] 1. A color developer sheet in which a base material and a sheet-like molded product made of a mixture of an olefin resin, a color developer, tacifier, and a dye-adsorbing inorganic substance are bonded and integrated. 2. The color developer sheet according to claim 1, wherein the base material is paper. 3. The color developer sheet according to claim 1, wherein the sheet-like molding and the substrate are integrally joined by an extrusion lamination method. 4. The color developer sheet according to claim 1, which is a mixture containing an opacifying agent. 5. The color developer sheet according to claim 1, wherein a part of the olefin resin is a functional group-containing olefin resin.