JPS6047070A - 4,4-di-n-pentyloxydiphenyl sulfone - Google Patents

Abstract

PURPOSE:To provide the titled compd. which has excellent developability and is useful as a sensitizer for a thermochromic recording material, by pentylating bisphenol S. CONSTITUTION:Bisphenol S (4,4'-dihydroxydiphenyl sulfone) is pentylated in a conventional manner to obtain a sensitizer composed of 4,4'-di-N-pentyloxydiphenyl sulfone of the formula. One pt. colorless or light-colored developing dye (A) (e.g. 3-N-methylcyclohexylamino-6-methyl-7-phenylaminofluoran) capable of developing a color by an acidic material, 1-10pts. org. acidic material (B) (e.g. benzyl p-hydroxybenzoate) capable of causing component A to develop a color at an elevated temp., 0.3-6.0pts. said sensitizer (C) and a water-soluble binder (D) (e.g. PVA) are dissolved or dispersed in water to obtain a coating soln., which is then applied to a substrate and dried to obtain a thermochromic recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-sensitive color-forming recording material that has excellent low-temperature color-forming properties.

Coloring dyes (hereinafter referred to as ``coloring dyes'') that are colored by acidic substances can be used to produce lrh colors or pale colors (hereinafter referred to as ``colorable dyes'').
In the thermal recording method 2, in which color develops when heated using a color developer, as the speed of communication recording devices such as facsimile machines that use it become faster, it is necessary to minimize the color development speed or low-temperature color development (color development sensitivity) of the recording paper. It is requested that it be increased. The present invention is intended to meet this demand, and the inventors have completed the present invention by discovering a new sensitizer.

That is, the present invention relates to 4,4'-di-n-panthyloxydiphenylsulfone 0 , a colorless or light-colored color-forming dye that develops color with an acidic substance, and a color-forming dye that develops color when heated. The organic acid substance contains benzyl p-hydroxybenzoate or 4-hydroxybenzoate. 41-Impropoxydiphenyl sulfone.

Currently, higher fatty acid amides are the most common sensitizers used for heat-sensitive color-forming recording lines, especially for heat-sensitive recording paper, but the 4,4'-di-n-pentyloxydiphenyl sulfone of the present invention Compared to higher fatty acid amides, it has a much superior sensitizing effect. This higher fatty acid amide for bisphenol A (BPA1bis(p-hydroxytophenylsin-dimethylmethane) and benzyl p-hydroxybenzoate), which is currently in practical use as a color developer in thermal recording paper, and the present invention's 4
, 4'-dipentylox-1sidiphenylsulfone as a sensitizer in the low temperature range (65 to 85°C) was first investigated.
Shown in Table and Table 2. The measured values in the table indicate the whiteness of the background produced and colored in the Examples and Comparative Examples described below and the color density at each temperature listed,
The larger the numerical value, the greater the color density. In these experiments the chromogenic dye was 3-N-methylcycloa
Hexylamino-6-methyl-7-noenylaminofluorane (R, a dye that develops a bright red color) was used.

First table color developer: BPA ratio -1 to 1 - α12α12 [11311150j
7123 ratio -2 to 1 Takasuki Erotoshi amide α12 α12
[L15 0.24 α49 α77 2nd table Sll: p-hydroxy Yasushima Koya benzyl ratio -1
-2'[1120,14[1,17[1,321741
, 11 ratio -2-21N/JtjlW 10,000 waves 7 mid l1
lL130.16 [40G, 77 1.04 1.1
2 These measured values show that 4,4'-bis--omethyloxydiphenyl sulfone has a far superior sensitizing effect compared to higher fatty acid amides in the low temperature range of 65' to 85°C. Another interesting phenomenon is 4,4
When '-di-n-pentyloxydiphenylsulfone is used, there is a tendency to increase the whiteness of the skin.

4. The effect of 4'-Cn-J methyloxydiphenylsulfone as a sensitizer in the low temperature range was demonstrated by using 4-hydroxy-4'-impropoxydiphenylsulfone (Japanese Patent Application No. 12020945/1983) as a color developer. It appears very clearly in some cases. This is shown in Table 3. (
The color-forming dyes used were the same as above.
280,52 Phenylsulfone 4. The effect of 4'-di-n-pentyloxydiphenylsulfone as a sensitizer is due to the fact that it can be used as a color-forming dye with substances other than the above-mentioned fluoran compounds, such as phenyl-diethylamino-
When using 6-methyl-7-phenylaminofluorane (colors black) or crystal violet lactone (colors f-color), almost the same tendency as above appears.

4.4'-N-hentyl phenyl sulfone not only enhances the effects of other color developers as described above, but also has the following effects.

In other words, in thermal recording paper using BPA or p-hydroxyammonium 7@benzyl flavourate as a color developer, the colored portion tends to fade or disappear due to cosmetic cream or dirt from fingertips, etc. This tendency is significantly suppressed by the combined use of 'I'-pentyloxydiphenyl sulfone. In addition, benzyl p-hydroxybenzoate is used as a good color developer with low-temperature color development properties, but the color development area partially or completely becomes white powder as time passes, which is the so-called r-powdering phenomenon. (This phenomenon is also called "whitening phenomenon," and it has the disadvantage that it tends to occur due to the free precipitation of the blood-tinting agent from the heat-sensitive mixed composition applied to the paper surface.4,4
The combined use of '-di-n-pentyloxydiphenyl sulfone is also extremely effective in suppressing this "dusting phenomenon." In addition, thermosensitive recording paper produced using 4-hydroxy-4'-isozoloboxydiphenylsulfo/ as a blood tinting agent in combination with 4,4'-cyhenthyloxydiphenylsulfone is Compared to the case where a sensitizing agent is used in combination with EPA or benzyl p-hydroxybenzoate, there is less discoloration due to cosmetic cream or dirt from fingertips, and no "fluffing phenomenon" is observed even during storage at the mouth of a burn.

4,4'-di-n-pentyloxydiphenylsulfone in the present invention is a new substance, which is obtained by pentylating industrially easily available bisphenol (4,4'-dihydroxydiphenylsulfone) according to a conventional method. It's something I've been waiting for.

4. Sensitizing heat-sensitive color-forming recording materials (such as, but not limited to, thermal recording paper or Tong/Tun thermal recording Q paper) with 4'-di-n-pentyloxydiphenyl sulfone. The method for using it as a sensitizer is the same as that for known sensitizers for heat-sensitive recording materials. That is, a thermal recording medium is produced by applying a suspension of fine particles of this substance, fine particles of a color developer, and fine particles of a color-forming dye in an aqueous solution of a water-bathable binder and drying it. can produce profit.

Examples of color-forming dyes include fluoran type, phthalide type,
Leuco type dyes such as lactam type, lylphenylmethane type and spiropyran type can be used, but are not limited to these, and it goes without saying that these can be used in combination.

Examples of water-soluble binders include polyvinyl thicol,
Hydroxyethyl cellulose, carboxymethyl cellulose, styrene-maleic anhydride m copolymer salt, styrene-butadieno emulsion, hinyl acetate-maleic anhydride post-emulsion, polyacrylate, polyacrylamide.

Starch) A1 Casein, gum arabic, etc. can be mentioned, but are not limited to these.

The above suspension may further contain dispersants (e.g. sodium dioctylsuccinate, sodium dodecylbenzenesulfonate, thorium salts of lauryl alcohol sulfate, fatty acid metal salts, etc.), desensitizers (e.g. aliphatic heavy alcohols, solid '1tlli flucol, polyethylene, glycol, guanidine conductor, etc.), anti-adhesives (stearic acid, zinc stearate, calcium stearate, carnauba wax, 79 rough-in wax, ester wax, etc.), fillers (e.g. clay, talc) , kaolin, satin white, titanium oxide, calcium carbonate, magnesium carbonate, barium sulfate, magnesium silicate, aluminum silicate, etc.), antifoaming agents, polymeric light stabilizers, fluorescent whitening agents, and the like.

The above-mentioned molten gradient is not only used for heat-sensitive recording, but also applied to a conductive layer supported on a support as in, for example, Japanese Patent Publications No. 51-16154 and No. 51-16155. When the coating film is dried, an electrically conductive heat-sensitive recording material is obtained.

In the present invention, C4,4'-d-n-pentyloxydiphenyl sulfone is used in α3 to 6 parts per part of color-forming dye.
．． 0 parts, preferably 5 to 3 parts of LL are used. Use 1#
If i is too small, n will not be as effective as a sensitizer, and even if used in excess, there will be no particular effect and it will be uneconomical.

This substance may also be used with other JcfJ sensitizers.
” - Noh.

The amount of color developer to be used is not necessarily determined by the properties of the color developer, but 1 to 10 parts per 1 part of color-forming dye is temporary, and BPA and 4-hydroxy -41-isopropoxydiphenylsulfone preferably has 1 to 4 parts.

Production sequence 4.4'-dihydroxydiphenylsulfone 25p, n-bromide is methyl 7I69 and sodium carbonate 15jl
was added to 200 d of ethanol, the temperature was gradually raised while stirring, and the reaction was continued at reflux F for 4 hours. After the reaction was completed, the reaction mixture was cooled to remove the precipitate, and then ethanol was distilled off. 100 m/ml of toluene was added to the residue to dissolve the solution, and a small amount of insoluble matter was removed. The toluene bath solution was washed with 1q6 sodium hydroxide bath solution and then with warm water, and about 60 ml of toluene was distilled off. The distilled residue is cooled and the precipitated crystals are collected, washed with toluene from the sunset, and then dried to yield 4,4'-U-n-hentyloxydiphenylsulfo 7312F with a melting point of 87.
Obtained as colorless crystals at 8-89.3°C.

Example 1 BPA i CL59. 1596 aqueous solution 41 of polyvinyl alcohol (Kuraray Co., Ltd., "Clan-105J")
．． 5jl, mineral-filled f8+ (Engel Nord, [aw
-90J) aOP and pure water 4G, 0. P was placed in a 250 m polyethylene bottle with 150 jl of glass beads (diameter 1 to 5 mm), sealed tightly, and placed in a paint conditioner made by RθdDθvi1, and shaken at a frequency of 660 times/min for 8 hours. Remove and particle size 2
An aqueous suspension of ~3μ BPA was obtained (liquid A).

4,4'-q-n-hentyloxydiphenylsulfone 7, O'p, 15% aqueous solution of polyvinyl alcohol (same as Example 1) 41.5jl inorganic filler (same as Example 1) ii, SP and pure water 40.09 were placed in a 250 t/t polyethylene bottle with glass beads 150F, the bottle was tightly capped and shaken with paint conditioner at a frequency of 660 times/min for 5 hours, and the glass beads were removed. An aqueous 1Mi aqueous solution of '-di-n-ni/methyloxydiphenylsulfone was obtained (solution B).

In addition, 3-N-methylcyclohexylamino-6-methyl-7-phenylaminofluorane Z02, 15% aqueous solution of polyvinyl alcohol (same as above), 41.5Ps, mineral-free filler (same as above) 11.52, and pure water 4 aop
was placed in a 2501 Ill polyethylene bottle with Glass Peas 1502, the bottle was tightly capped, and shaken for 5 hours at a frequency of 660 times/min using a drop-in conditioner.The glass beads were removed and an aqueous suspension of fluoran compound (particle size
~3 μ) was obtained (liquid C).

Mix 1031 of liquid A and 5F each of liquid B and liquid C,
A coating solution was prepared by stirring for 20 minutes.

This coating solution was applied to white B paper using a wire rod Nα12 and dried for 2 minutes with warm air at 60° C. to produce a thermal recording paper (thermal recording paper number “Real-1”).

This thermal recording paper was tested at 65°C, 70°C, 75°C, 80°C and 85°C using a dry heat tester (Kishino Scientific Products Co., Ltd.).
Both sides were heated for 5 seconds at a temperature of °C to develop color (black). The color density of the colored surface and the white discoloration of the background of the uncolored paper were measured using a Macbeth reflection densitometer model 514 (using Kutsuten Filterna 106). (column)).

Benzyl p-hydroxybenzoate was used in place of the color developer BIPA in Example 1 and 2, and the aqueous suspension thereof was prepared.
(Liquid A') The same feeding and training as in Example 1 was carried out using this liquid A' instead of liquid A.

The measured values are shown in Table 2 (shown in the column of thermal recording paper number "Real-2").

Example 6 4-Hydroxy-4'-isopropoxydiphenyl sulfone was used in place of the color developer BPA in Example 1, and an aqueous suspension thereof was prepared. An experiment similar to that in Example 1 was conducted using this A' solution.

The measured values are in Table 3 (column of thermal recording paper number "Real-3")
This is shown in .

Comparative Example 1 Inorganic filler (same as in Example 1) 1a5jl, polyvinyl alcohol (same as in Example 1) 15
41.5jl of aqueous solution and 40ml of pure water. Op was placed in a 250at polyethylene bottle with 1 sop of glass peas, the bottle was tightly capped, and the bottle was shaken with a paint conditioner at a frequency of 650 times/min for 5 hours.The glass peas were then removed to obtain an aqueous suspension of inorganic filler ( B liquid).

Three types of thermal recording papers were manufactured in the same manner as in Examples 1.2 and 3 using this B liquid instead of B liquid in Examples 1.2 and 6 (the thermal recording paper number was changed to "ratio"). -1
-1", "ratio-1-2" and "ratio-1-6")
. These recording papers were colored under the same conditions as in Example 1,
The color density and whitening of the background were measured. Those values are shown in Tables 1, 2 and 3, respectively.

Comparison Reli 2 The sensitizer 4,4'-J-n- in Example 1 was substituted with rope-grade fatty amide (the sensitizer "Amide AP-IJ" sold by Nippon Kasei Co., Ltd.) instead of methyloxycyphenylsulfone.
) was used to make an aqueous suspension thereof (liquid B').

This B' solution was used in place of the B solution in Examples 1 and 2, and 2mm thermal recording paper was produced in the same manner as in Examples 1 and 2 (the thermal recording paper number was changed to "ratio-2"). -1
” and “ratio-2-2”). These recording papers were allowed to develop color under the same conditions as in Example 1, and the color density and whitening of the background were measured. The values are shown in Tables 1 and 2, respectively.

Claims (1)

[Scope of Claims] 1) 4.4'-1)-n-a anthyloxydiphenyl sulfone 2) A colorless or light-colored chromogenic dye that develops color with an acidic substance, an organic acid that causes the chromogenic dye to develop color when heated 1. A heat-sensitive color-developing recording material, characterized in that it contains a substance such as 4,4'-di-n-pentyloxydiphenylsulfone. 3) The heat-sensitive color-developing recording material according to claim 2, wherein the organic acidic substance is benzyl p-hydroxybenzoate or 4-hydroxy-41-impropoxydiphenylsulfone.