DE2120920A1 - Sensitized sheet for pressure or heat sensitive copier papers - Google Patents

Description

FATE N TAXWKtTE

DR.E. WIEGAND DlPL-ING. W. NIEMANN 9

DR. M. KÖHLER DIPL-ING, C. GERNHARDT ά

MDNCHEN HAMBURG TELEPHONE: 55 54 76 8000 MUNICH 15, TELEGRAMS = KARPATENt NUSSBAUMSTRASSEIO

■ 28. April 1971 W 40 479/71 Ko / DE

Fuji Photo Film Co. Ltd, Ashigara-Kamigun, Kanagawa / Japan

Sensitized sheet for pressure or heat sensitive Copy papers

The invention is concerned with a sensitized Sheets for pressure or heat sensitive copier papers and is particularly concerned with a pressure or heat sensitive Copy paper using a phenolic resin as a sensitizer.

In the pressure- and heat-sensitive copier papers, such as those described in US Pat. No. 2,712,507 » 2,730,465, 2,730,457 and 3,418,250, solutions containing microcapsules are practically colorless organic compound, hereinafter referred to as color former, with electron donor properties and yellowing reactivity and an electron-attracting adsorbent, hereinafter referred to as a sensitizer, used. '

10 9 8 8 5/1139 ^ ₀ ORIGINAL

Typical sensitizers are, for example Clays, such as acid clays, active clay, attapulgite, zeolites or bentonites, organic acidic compounds such as succinic acid, Tannic acid or bile acid and the like are listed.

Recently, the use of a phenolic resin has been used to increase the stabilities of these sensitizers suggested.

In British patent specification 1 065 587 the ver

k turn of an oil-soluble acidic polymer, for example of a phenolic resin, together with an acidic material such as attapulgite, as a sensitizing agent, and in the In Japanese Patent 511,757, such polymers, for example phenolic resins, are used as sensitizers. However, although these phenolic resins as sensitizers usually have a distinctive color image, the opposite Water is stable when reacted with a color former, for example crystal violet lactone, benzoyl leucomethylene blue and the like, there are disadvantages that the color image is poor in weatherability in that it is easily discolored upon exposure to sunlight and left to stand.

) An object of the invention is a printing or

heat sensitive copy paper. Another object: 'of the invention consists of a new sensitizer. Another object of the invention is an improved phenolic resin, which is valuable as a 'sensitizer'. One Another object of the invention is to provide a method of making valuable practical pressure sensitive ones Copier papers and a process for improving the weathering resistance of phenolic resins as sensitizers.

The above objects of the invention are easily achieved when an alkaline material is added to the phenolic resins

10 9 8 8 5/1139 ORIGINAL INSPECTED

120920

is added. ■ ".

The alkaline material is generally in a solvent such as water, methanol, ethanol and the like ·. ' solved, but it can> im EaIl "the application of an oil solution Phenolic resin may be beneficial, to dissolve it in methanol, ethanol and the like: - ·.

To the embodiments for alkaline materials include hydroxides or carbonates of alkali metals..like Sodium, potassium and the like ^ or alkaline earth metals ", such as calcium, magnesium and the like. '".-"' - ■

When the solution of the alkaline material is added to the phenolic resin solution, the amount of the alkaline material added is preferably in the range of 0.5 to 5 parts to: 100. Parts, of the phenolic resin. The phenol, harzlösung'kann.durch'Auflösen of the phenolic resin in a solvent ^such-as: are toluene, xylene and the like, benzene, wherein the Phenolharze'in the vorstehen- * British ^{Patentsehriftund.} Japanese Patent Publication are described, 'For example phenol aldehyde resins, phenol acetylene resins and the like. '

The above two types of solvents are regarding the quantitative relationship between the resolved en-. St off and. not particularly limited to the solvent, because after the solutions have been applied to a carrier, dried and evaporated. For: purpose of increasing the Phenolic resins can also be used to adsorb an adsorptive material »which even when contacted with: the 'color former: is hardly colored, for example talc or bauxite or an absorbent material that has hitherto been used known as a sensitizer, for example acidic Clay, active clay, attapulgite and the like, in the solution of the .; Incorporating phenolic resin and the alkaline material. . '

1 0 9 8.8 5/1139 OfMQiNAi tN6PECTED

The activity in the application of these sensitizers is increased by the alkaline material, thereby obtaining a valuable pressure-sensitive copying paper which is suitable for the formation of pronounced colorations with high density. Most importantly, it is in the method according to the invention, the weather resistance to improve the color images formed on the phenolic resin by the alkaline material and another advantage consists in increasing the activity of the known sensitizers.

The above fact becomes easy due to the facts clarified that the weatherability of the color images even in the case of adding less coloring adsorbent Material is increased to the coating solution.

The practical application of the resulting phenolic resin solution is carried out by adding them individually or together with the microcapsules containing the color former, as follows specified, is mounted on a carrier such as paper.

Another embodiment is also successful with regard to the steps of the previous application or coating of the phenolic resin on the carrier and the subsequent one Drawing up the solution of the alkaline material thereon.

As color formers, crystal violet lac ton, benzoyl leucomethylene blue, malachite green lactone, Rhodamine-ß-lactam, 3-dialkylamino-7-dialkylaminofluorane, 3-methyl-2,2-spirobi- (benzo- / f7 ~ chromene) and other known compounds can be used.

In general, the color formers can be used for the pressure-sensitive Copy papers generally as mixtures to complete instant color formation and lightfastness of the color image can be used.

10 9 8 8 5/1139 ORIGlNAt INSPECTED

There is ζ. B. the well-known combination of a high-speed color former, such as crystal violet lactone, as a primary color former with a low speed color former with excellent lightfastness, such as benzoyl leucomethylene blue.

However, if the combined color formers are contacted with the phenolic resin and printed, the result is crystal violet lactone color is rapidly formed on the phenolic resin layer while it takes a long time for the benzoyl leucomethylene blue colors, and the colored image formed from the crystal violet lactone is easily colored.

In the case of using a sensitizer in accordance with According to the invention, the above deficiencies are eliminated, as can be seen from the following examples.

While pressure-sensitive copier papers that form a black color image by using a mixture of The pressure-sensitive copier paper is used to produce different color images that give different tints suitable according to the invention to form a pure black image which is not changed under sunlight.

The usual method of making microcapsules, which contain the color former can according to the US patent 2,600,457 specified procedures are carried out; an embodiment of this is given below:

10 parts of an acid-treated pigskin gelatin and 10 parts Guramiarabicum were dissolved in 400 parts of water at 40 ⁰ C. After adding 0.2 part of Turey oil as an emulsifier, 40 parts of the color former oil were emulsified and dispersed therein. The color former oil was prepared by dissolving 2 fo crystal violet lactone and 1.5 $ benzoyl leucomethylene blue in an oil composed of 4 parts of chlorinated diphenyl and one part of kerosene.

After the oil droplets have an average particle size of 5 microns was emulsification

10 9 8 8 5/113 9

interrupted and added to 4O ⁰ C heated water so that 900 parts were obtained under stirring. Here, the temperature of the solution must be held so that it does not drop below 40 ^0C. The pH of the solution is then adjusted to 4.0 to 4.2 by adding 10% acetic acid in order to bring about coacervation.

After 20 minutes of stirring the system, the coacervate gels around the oil droplets.

7 parts of 37 $ sodium formaldehyde was added when the temperature of the solution reached 20 C ^a and when they reached 10 C, the mixture to pH 9 by careful addition was a 15 / & - adjusted aqueous solution of caustic soda.

Then this was received:
heated for 20 minutes.

Then the mixture obtained was heated to 50 ^° C. with stirring

The resulting microcapsules were heated to 30 ^° C.

bolted and on a paper of 40 g / m in an amount of

6 g / m, based on the pesticide content, spread and then dried.

The following examples serve to further illustrate the invention without limiting it.

1 0 9 8 8 5 / TT 3 9

example 1

A phenolic resin was obtained by the following polymerization:

170 g of p-phenylphenol, 65 g of a 37 # aqueous forraaldehyde solution, 10 cc concentrated (37 #) hydrochloric acid, 19 g. Oxalic anhydride and 40 can of water were placed in a reactor and refluxed for 10 hours at the boiling point of the water. Subsequently, the reactants were cooled, the aqueous layer separated and the phenolic resin material distilled under reduced pressure until the temperature of the flask was 120-130 ⁰ C. The resin was placed in a stainless steel vessel and cooled to obtain the phenolic resin.

10 g of the phenolic resin dissolved in 40 ecm xylene were with 0.1 caustic soda, dissolved in 10 ecm of methanol, mixed and

ρ p

based on a paper of 40 g / m 2 in an amount of 5 g / m 2 on phenolic resin, applied by means of a spreading stick and dried.

Comparative example 1

For comparison purposes, a solution of 10 g of des Phenolic resin in 50 ecm xylene applied to the paper at 40 g / m, so that 40 g / m of the phenol by means of a pull-up stick raised and dried.

Comparison test result 1

A capsule sheet with a peeled layer of microcapsules containing crystal violet lactone was opened the sheets according to Example 1 and Comparative Example 1, respectively

piled up and with a pressure of 60 kg / cm for training

1 0 9 8 B .5 bM 1 3 9.

OfBGfNAt INSPECTED

M 2 0 9 2 0

a pronounced coloring.

The spectral absorption curves of the color images after one hour were determined at a wavelength of 700-380 m » and the curves of the color images were continued after exposure to sunlight for one hour and three hours, respectively certainly; the results are shown in FIG.

The determinations of the spectral absorption curves were carried out by means of the spectrophotometer Beckman D B-Typ of Tokyo Shibaura Electric Co., Ltd.

In Fig. 1, I denotes the product of Example 1 and II denotes the product of Comparative Example 1, while A is the fresh density, B is the density after exposure to sunlight for one hour, and C is the density after indicate exposure to sunlight for three hours, these terms being used in the same way for the following Examples and comparative examples are used.

The lightfastness values calculated according to the following equation are given in Table I. -

Density, the maximum absorption after exposure to solar

τιβττ aer juicnxecnxae . "~ fresh density of the maxi
paint absorption
Table I. 60.8 %
$ 48.5> - · ..-. -j- Sunlight sunlight
? (1 hour) '(3 hours) Example t
Comparative example 1 $ 67.1

ORIGINAL INSPECTED

1 09885/1 139

It is found that the incorporation of the alkaline material in the phenolic resin remarkably improves the fastness to licit of the crystal violet lactone shown in the above table, and from the absorption curve of the accompanying FIG. _1, the change in color tone is reduced.

Further, a sheet coated with microcapsules containing crystal violet and benzoylleucomethylene blue was piled up on the above sensitizing sheet and pressed with a pressure of 600 kg / cm to form a color image. The change in image density at maximum absorption (610 m * χ ) after storage in an indoor space is shown in Table II.

Table II

Days during the
Storage in one
space example 1 Comparative example 1 0 days 0.750 0.74-7 5 days 0.680 0.510 10 days 0.630 0.470 20 days 0.560 0.430

Since, in the case of a sensitized sheet containing no alkaline material, the formed color image of the Crystal violet lactons became remarkably discolored on storage for 5 days under room conditions, and the benzoylleucomethylene blue was not discolored after being stored in a room for 5 days, the color image remarkably faded after 5 days. On the other hand, there was an awareness questionnaire with the alkaline material the discoloration of the Crystal violet lactons difficult and therefore the density became

10 9 8 8 5/1139

of the color image after storage for 5 days decreased. -

From the above values, it can be seen that the disadvantages in Comparative Example 1 by the inventive Procedures were remarkably improved.

Example 2

To a dispersion of 10 g of talc, dispersed in 40 cc of xylene was gradually added 10g of the same Phenolhar- Ψ zes as zugesetet in Example 1, dissolved in 40 cc of xylene, while stirring.

Then 0.2 g of caustic potassium, dissolved in 10 ecm Methanol, gradually added to make the paint. The paint was applied to a paper of 40 g / m 2 in an amount of 10 g / m, based on the solids content, by means of a Spreading stick drawn up and dried.

Comparative example 2

To a dispersion of 10 g of talc, dispersed in 40 ecm Xylene, gradually became 10g of the same phenolic resin as in Example 1, dissolved in 50 ecm xylene, with stirring for Preparation of the paint added. The paint was based on a paper of 40 g / m 2 in an amount of 10 g / m 2 to the solids content, drawn up by means of a spreading stick and dried.

Comparative test results 2

The experiment was carried out in the same manner as in Comparative Experiment Result 1 and the absorption curve; of the color image after exposure to sunlight in the same spectrophotometer as determined above, which is in the

INSPECTED

109 8-8 5/1 1 3-9 «i / · .; · ■

enclosed pig. 2 is reproduced. The light fastness value is given in Table III.

Table III

Sunlight Sunlight (1 hour) (3 hours)

Example 2 66.4 % ""'"' 56.5 #

Comparative Example 2 47.3 % -.,., .. 38.5 #

As in the case of the comparative test result one could at the above results are found that would improve the fastness to light with crystal violet remarkable ". '' ^-:

Furthermore, a sheet covered with microcapsules was which contained crystal violet lactone and benzoylleucomethylene blue, stacked on top of the above sensitized sheet and pressed with a pressure of 600 kg / cm to form the color image.

The change in image density at maximum absorption (610 mn) after storage under room conditions results from Table IV. ', - "·

Table IV

Days of storage
in the room Example 2 Comparative example 2 0 days 1.003 .0.995 '5 days "' 0.910 Ό, 860 10 days '■■' "" '■' 0.850 0.590 20 days 0.780 Öv55O "

As with comparative test result 1, the result is

109885/1 139 OBfflNAt (N8PECTED

The effect of the incorporation of the alkaline material into the phenolic resin is clear.

Example 5

0.2 g of caustic soda dissolved in 40 ecm of water were added 10g of sour clay added and gradually continued a solution of the same phenolic resin as in Example 1, dissolved in 50 ecm of the mixed solvent xylene / methyl alcohol (1: 1), added while stirring the system. Finally, a styrene-butadiene rubber / klatex (designation DOW 620) in an amount of 4 g, based on solids content, for production added to the application solution.

The solution was applied to a paper of 40 g / m 2 in an amount of 8 g / m, based on the solids content, means a coating stick drawn up and dried.

Comparative example 3 ' ^:

10 g of sour clay were gradually added to 50 ”eccm of water Stirring was added and then gradually 10 g of the same phenolic resin as in Example 1 dissolved in a mixed solvent from xylene / methanol (1: 1), under. Stir mixed.

Finally, a styrofoam butadiene rubber latex was made (DOW 620) in an amount of 4 g, based on the solids content, was added to prepare the solution.

The solution was on a paper of 40 g / m in a

Amount of 8 g / m, based on the pesticide content, means pulled out with a spreading stick and dried.

Comparative test results.ss.e 5. "..,. .,,. . , ·,

The experiment was carried out in the same way as for Comparative Experiment Result 1 and the results are given in the accompanying Pig. 3, as well as Table V.

1 Q 9 8 ® S / I 13 9 ORlOtNAL {NSPECTED

Table V

Sunlight Sunlight (1 hour) (3 hours)

Example 3 61.5 # 48.5

Comparative Example 3 47.3 # 39.1

From the above values it follows that the Fastness to light of crystal violet lactone as in Comparative Test Results 1 and 2 is remarkably improved became.

Further, a sheet coated with microcapsules containing crystal violet lactone and benzoyl leucomethylene blue was piled up on the above sensitized sheet and pressed with a pressure of 600 kg / cm to form the color image. The change in the image density at the maximum absorption (610 m » ) after storage under room conditions is shown in Table VI.

Table VI Comparative example 3 Days storage in
a room Example 3 1.02
0.780
0.710
0.65 0 days
5 days
10 days
20 days 1.26
1.12
0.960
0.910

The same effects as in Comparative Experiment Result 1 could be obtained _f . ^ .-

10 9 8 8 5/1 % 3 9 ORlGlMAt INSPECTED

A sheet covered with microcapsules that contains a Ver binding according to the formula

° ^ ^CH2 ^>

was applied to the above sensitized sheet stacked and pressed with a pressure of 600 kg / cm to form an image.

The spectral absorption curve of the specimen after 1 hour was determined, and then that of the specimen after exposure to sunlight for 1 hour respectively 3 hours; the results are in the attached. Fig. 4 included.

From the spectral absorption was confirmed that the maximum absorption χ according to Example 3 from initially 600 τα A ₁ to 590 m "in the suspension ai sunlight for 1 hour and further to 580 m * changed upon exposure to sunlight for 3 hours.

However, in the sensitizing sheet according to Comparative Example 3, the maximum absorption changed from initially 600 myu to 570 when exposed to sunlight for 1 hour and further changed to 560 m A ₁ when exposed to sunlight for 3 hours.

The compound according to the formula

CH ₂ - <Ö} N _

10 9 8 8 5/113 &. OfWQlNAL INSPECTED

so showed little change in tint in that sensitized sheet according to example 3.

The term "sensitized sheet" includes "sensitization · arc" .

09 88 5/1139

BATH ORIGINAL

Claims (10)

- OK - Claims «Sensitized arch leading to the formation of a pronounced Color when in contact with a practically colorless color former is capable, consisting of a carrier with a layer thereon containing a phenolic resin and an alkaline material. 2. Sensitized sheet, which is useful for developing a distinctive color when contacting a person | colorless color former, consisting of a carrier with a layer of a phenolic resin and a layer of an alkaline material thereon. 3. Sensitized sheet, which is handy for forming a distinctive color when contacting a person colorless color former, consisting of a carrier with a layer formed on it, which is a phenolic resin, contains an alkaline material and an adsorbent substance. 4. Sensitized sheet according to claim 3, characterized in that that the adsorbent substance consists of a practically non-color-forming substance upon contacting with a practically colorless color former. w 5 · Sensitized sheet-according to claim 3, characterized in that the adsorbing substance consists of a color-forming substance when it comes into contact with a practically colorless color-forming agent. 6. Sensitized sheet consisting of a backing with a phenolic resin layer thereon and a layer of an alkaline material, at least one of which layers is an adsorbent substance contains. 10 9 8 8 5/1139 ORIGINAL INSPECTED 7. Sensitizing sheet after. Claim 6, characterized
characterized in that the adsorbent substance consists of a
practically non-color-forming substance when it comes into contact with a practically colorless color-forming agent. 8. Sensitized sheet according to claim 6, characterized in that that the adsorbent substance consists of a color-forming substance in contact with a practical colorless color former. 10 9 8 8 5/1 1.3 9 ORiGINAL INSPECTED