JPH1176802A - Manufacturing of microcapsule for pressure-sensitive duplicating sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microcapsule for a pressure-sensitive duplicating sheet which is free from the deterioration of a developed color density and shows outstanding pressure resistance and anti-frictional properties. SOLUTION: This microcapsule is obtained by emulsifying an inner phase containing polyvalent isocyanate and a hydrophobic core substance obtained by dissolving an electron donative coupler in a hydrophobic liquid, in an aqueous phase and forming a synthetic resin coat on the interface between liquid droplets through adding a polyvalent amine. In this case, a polycyclic aliphatic isocyanate obtained by modifying a polycyclic aliphatic diisocyanate expressed by the formula (wherein k is 1-2; j and m are 1-5; and h is an integer of 0-2) with an alkyleneoxide adduct of the polyvalent amine, is used as the polyvalent isocyanate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing microcapsules for pressure-sensitive copying paper. More specifically, the present invention relates to a method for producing a pressure-sensitive copying paper microcapsule having excellent pressure resistance and friction resistance.

[0002]

2. Description of the Related Art Microcapsules have been studied in a wide variety of fields, such as recording materials such as pressure-sensitive recording materials and heat-sensitive recording materials, pharmaceuticals, agricultural chemicals, adhesives, foods, rust preventives, liquid crystals, and temperature indicating materials. The product has been put to practical use or practical use test. In particular, a number of techniques have already been proposed for microencapsulation of hydrophobic substances. Among them, a coacervation method (phase separation method) using gelatin, an interfacial polymerization method, an in-situ polymerization method, and the like have been proposed. Are known.
In early microcapsules, gelatin-based coacervation microcapsules were often used, but only low-concentration microcapsules could be obtained, and there were restrictions on storage due to the use of natural gelatin as a raw material. Therefore, it is now changing to a synthetic resin microcapsule. Among synthetic resin microcapsules, in
-Situ polymerization microcapsules are used as microcapsules for pressure-sensitive copying paper in terms of performance, raw materials, and production cost. However, there are drawbacks such as formalin generated during the reaction and formalin remaining in the microcapsule liquid, and it is difficult to produce microcapsules having a large particle diameter.

[0003] Interfacial polymerization microcapsules have the advantage that microcapsules having a large particle diameter can be obtained and microencapsulation can be performed in a short time. On the other hand, the obtained microcapsules are mainly used. When used for pressure-sensitive copying paper, the solvent resistance, heat resistance, pressure resistance and friction resistance are insufficient. Poor solvent resistance, when pressure-sensitive copying paper is printed by flexo or offset method,
The core substance in the microcapsules may be extracted by the solvent used for printing. Also, if the heat resistance is poor, when coating and drying the microcapsules, the drying heat causes odor due to the vapor pressure of the hydrophobic liquid used for the pressure-sensitive copying paper. There is a drawback that the lower sheet may be contaminated when stored in a storage device.
If the pressure resistance is poor, the microcapsules will burst at a weak pressure, causing pressure fogging. In addition, when the friction resistance is poor, there is a drawback that the microcapsules are ruptured by weak rubbing and cause rubbing. Various proposals have been made to compensate for these disadvantages.

For example, JP-A-52-130708 discloses a method using a reaction system of carbodiimide-modified tolylene diisocyanate and hexamethylene diisocyanate with a polyamine, and JP-A-53-70985 discloses a biuret group. Using a reaction system of an aliphatic diisocyanate containing a compound with a polyvalent amine, JP-A-57-52
No. 238 discloses a method using an oxadiazinetrione-modified aliphatic diisocyanate and a polyvalent amine, and JP-A-57-140638 discloses a reaction of a combined use of polymethylene polyphenyl isocyanate and an aliphatic diisocyanate with a polyvalent amine. Using a system, JP-A-63-107
No. 741 discloses a method using a reaction system of a diisocyanate and a polyether polyol containing one amino group,
JP-A-63-116736 discloses a method using a reaction system of an alkylbenzene diisocyanate and a polyvalent amine, and JP-A-63-200830 discloses a combined use of an aliphatic diisocyanate and an isocyanurate ring-containing compound of an aliphatic diisocyanate. Using a reaction system of diisocyanate and an alkylene oxide adduct of an amine;
No. 7 discloses a method using a reaction system of a polyvalent isocyanate, an alkylene oxide adduct of a polyvalent amine and a polyvalent amine, and JP-A-4-63128 discloses an o-tolidine diisocyanate, an aliphatic diisocyanate and a modified product thereof. Methods using a reaction system with a polyvalent amine have been proposed, and some of them have been industrialized. However, pressure resistance and friction resistance are not sufficient, and there is still room for improvement.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a pressure-sensitive copying paper microcapsule having excellent pressure resistance and friction resistance.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned objects, and as a result, completed the present invention. That is, the present invention emulsifies an internal phase containing a polyvalent isocyanate and a hydrophobic core substance in which an electron-donating color former is dissolved in a hydrophobic liquid in an aqueous phase, and then adds a polyvalent amine, In a method for producing a microcapsule for a pressure-sensitive copying paper in which a synthetic resin film is formed at a liquid droplet interface, a polycyclic aliphatic diisocyanate represented by the general formula (1) or (2) is used as a polyvalent isocyanate. The present invention relates to a method for producing microcapsules for pressure-sensitive copying paper, characterized by using a polycyclic aliphatic isocyanate modified with an alkylene oxide adduct.

[0007]

Embedded image (Where k is 1-2, j and m are 1-5, h is 0-2
Represents an integer of

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The microcapsule for pressure-sensitive copying paper of the present invention is a polyvalent isocyanate obtained by modifying the polycyclic aliphatic diisocyanate represented by the aforementioned general formula (1) with an alkylene oxide adduct of a polyvalent amine. After emulsifying an internal phase containing this isocyanate and a hydrophobic core substance obtained by dissolving an electron-donating color developing agent in a hydrophobic liquid in an aqueous phase, a polyvalent amine is added, and at the droplet interface, It is manufactured by forming a synthetic resin film.

Specific examples of the polycyclic aliphatic diisocyanate represented by the general formula (1) used in the present invention include:
2,5 (6) -di (isocyanatomethyl) bicyclo [2,2,1] heptane, 2,5 (6) -di (isocyanatoethyl) bicyclo [2,2,1] heptane, 2,
5 (6) -di (isocyanatomethyl) bicyclo [2,
2,2] octane, 2,5 (6) -di (isocyanatoethyl) bicyclo [2,2,2] octane, 2-isocyanatomethyl-5 (6) -isocyanatoethylbicyclo [2,2,1] heptane, 2-isocyanatomethyl-5 (6) -isocyanatopropylbicyclo [2,
2,1] heptane, 2-isocyanatomethyl-5
(6) -isocyanatobutylbicyclo [2,2,1]
Heptane, 2-isocyanatomethyl-5 (6) -isocyanatopentylbicyclo [2,2,1] heptane,
2-isocyanatoethyl-5 (6) -isocyanatopropylbicyclo [2,2,1] heptane, 2-isocyanatoethyl-5 (6) -isocyanatobutylbicyclo [2,2,1] heptane, 2-isocyanatoethyl-5 (6) -isocyanatopentylbicyclo [2,
2,1] heptane, 2-isocyanatomethyl-5
(6) -isocyanatoethylbicyclo [2,2,2]
Octane, 2-isocyanatomethyl-5 (6) -isocyanatopropylbicyclo [2,2,2] octane,
2-isocyanatomethyl-5 (6) -isocyanatobutylbicyclo [2,2,2] octane, 2-isocyanatomethyl-5 (6) -isocyanatopentylbicyclo [2,2,2] octane, 2-isocyanatoethyl-5 (6) -isocyanatopropylbicyclo [2,
2,2] octane, 2-isocyanatoethyl-5
(6) -Isocyanatobutylbicyclo [2,2,2]
Octane, 2-isocyanatoethyl-5 (6) -isocyanatopentylbicyclo [2,2,2] octane,

3 (4), 8 (9) -di (isocyanate
Methyl) tricyclo [5,2,1,0 ^2,6] Decane, 3
(4), 8 (9) -di (isocyanatoethyl) tricy
Black [5,2,1,0^2,6] Decane, 3 (4) -isocyanate
Anetomethyl-8 (9) -isocyanatoethyltri
Cyclo [5,2,1,0^2,6] Decane, 3 (4) -iso
Cyanate methyl-8 (9) -isocyanatopropyl
Tricyclo [5,2,1,0^2,6] Decane, 3 (4)-
Isocyanatemethyl-8 (9) -isocyanate
Rutricyclo [5,2,1,0^2,6] Decane, 3 (4)
-Isocyanatomethyl-8 (9) -isocyanate
Nthyltricyclo [5,2,1,0^2,6] Decane, 3
(4) -isocyanatoethyl-8 (9) -isocyane
Propyltricyclo [5,2,1,0^2,6] Big
3 (4) -isocyanatoethyl-8 (9) -iso
Cyanate butyl tricyclo [5,2,1,0^2,6]
Can, 3 (4) -isocyanatoethyl-8 (9) -a
Socyanate pentyltricyclo [5,2,1,
0^2,6] Decane, 3 (4), 8 (9) -di (isocyane
Trimethyl) tricyclo [5,2,2,0^2,6] Unde
Can, 3 (4), 8 (9) -di (isocyanate
Ru) tricyclo [5,2,2,0^2,6] Undecane, 3
(4) -isocyanatomethyl-8 (9) -isocyane
Triethyltricyclo [5,2,2,0^2,6] Undeca
3 (4) -isocyanatomethyl-8 (9) -iso
Cyanate propyl tricyclo [5,2,2,0^2,6]
Undecane, 3 (4) -isocyanatomethyl-8
(9) -isocyanatobutyltricyclo [5,2,
2,0^2,6] Undecane, 3 (4) -isocyanate
Tyl-8 (9) -isocyanatopentyltricyclo
[5,2,2,0^2,6] Undecane, 3 (4) -isosi
Anetoethyl-8 (9) -isocyanatopropyl
Licyclo [5,2,2,0^2,6] Undecane, 3 (4)
-Isocyanatoethyl-8 (9) -isocyanate
Tyltricyclo [5,2,2,0^2,6] Undecane, 3
(4) -isocyanatoethyl-8 (9) -isocyane
Topopentyltricyclo [5,2,2,0^2,6] Unde
Kang,

4,9 (10) -diisocyanatomethyl
Tetracyclo (6,2,1,1^3,6, 0^2,7) Dodeca
, 4-isocyanatomethyl-9 (10) -isocyanate
Nate ethyl tetracyclo (6,2,1,1^3,6, 0
^2,7) Dodecane, 4-isocyanatomethyl-9 (1
0) -isocyanatopropyltetracyclo (6,2,
1,1 ^3,6, 0^2,7) Dodecane, 4-isocyanate
Cyl-9 (10) -isocyanatobutyltetracyclo
(6,2,1,1^3,6, 0^2,7) Dodecane, 4-isocyanate
Anetomethyl-9 (10) -isocyanatopentyl
Tetracyclo (6,2,1,1^3,6, 0^2,7) Dodeca
4,9 (10) -diisocyanatoethyltetracy
Black (6,2,1,1^3,6, 0^2,7) Dodecane, 4-a
Socyanate ethyl-9 (10) -isocyanate pro
Pyrtetracyclo (6,2,1,1^3,6, 0 ^2,7) Dode
Can, 4-isocyanatoethyl-9 (10) -isocyanate
Anate butyl tetracyclo (6,2,1,1^3,6, 0
^2,7) Dodecane, 4-isocyanatoethyl-9 (1
0) -isocyanatopentyltetracyclo (6,2
1,1^{3, 6}, 0^2,7) Dodecane, 4 (5), 9 (10)
-Diisocyanatomethyltetracyclo (6,2,2,
1^3,6, 0^2,7) Tridecane, 4 (5) -isocyanate
Tomethyl-9 (10) -isocyanatoethyltetracy
Black (6,2,2,1^3,6, 0^2,7) Tridecane, 4
(5) -Isocyanatomethyl-9 (10) -isocyanate
Nate propyl tetracyclo (6,2,2,1^3,6, 0
^2,7) Tridecane, 4 (5) -isocyanatomethyl-
9 (10) -isocyanatobutyltetracyclo (6,
2,2,1^3,6, 0^2,7) Tridecane, 4 (5) -iso
Cyanate methyl-9 (10) -isocyanate pliers
Letetracyclo (6,2,2,1^3,6, 0^2,7) Toride
Can, 4 (5), 9 (10) -diisocyanate ethyl
Tetracyclo (6,2,2,1^3,6, 0^2,7) Trideka
4- (5) -isocyanatoethyl-9 (10) -a
Socyanate propyl tetracyclo (6,2,2,1
^3,6, 0^2,7) Tridecane, 4 (5) -isocyanate
Ethyl-9 (10) -isocyanatobutyltetracyclyl
B (6,2,2,1^3,6, 0^2,7) Tridecane, 4
(5) -isocyanatoethyl-9 (10) -isocyanate
Natepentyltetracyclo (6,2,2,1^3,6, 0
^2,7) Tridecane, and the like.

Among these polycyclic aliphatic diisocyanates,
However, preferably, 2,5 (6) -di (isocyanate
Methyl) bicyclo [2,2,1] heptane, 2,5
(6) -di (isocyanatoethyl) bicyclo [2,
2,1] heptane, 2,5 (6) -di (isocyanate
Methyl) bicyclo [2,2,2] octane, 2,5
(6) -di (isocyanatoethyl) bicyclo [2,
2,2] octane, 2-isocyanatomethyl-5
(6) -isocyanatoethylbicyclo [2,2,1]
Heptane, 2-isocyanatomethyl-5 (6) -iso
Cyanateethylbicyclo [2,2,2] octane, 3
(4), 8 (9) -di (isocyanatomethyl) tricy
Black [5,2,1,0^2,6] Decane, 3 (4), 8
(9) -di (isocyanatoethyl) tricyclo [5,
2,1,0^2,6] Decane, 3 (4) -isocyanate
Cyl-8 (9) -isocyanatoethyltricyclo
[5,2,1,0^2,6] Decane, 4,9 (10) -Ji
Socyanate methyltetracyclo (6,2,1,
1^{3, 6}, 0^2,7) Dodecane, 4,9 (10) -diisosi
Anate ethyl tetracyclo (6,2,1,1^3,6, 0
^2,7) Dodecane, 4 (5), 9 (10) -diisocyane
Trimethyltetracyclo (6,2,2,1^3,6,
0^2,7) Tridecane, 4 (5), 9 (10) -diisos
Anate ethyl tetracyclo (6,2,2,1^3,6, 0
^2,7) Tridecane, more preferably 2,5 (6) -di
(Isocyanatomethyl) bicyclo [2,2,1] hep
Tan, 2,5 (6) -di (isocyanatoethyl) bis
Black [2,2,1] heptane, 2-isocyanatomethyl
-5 (6) -isocyanatoethylbicyclo [2,
2,1] heptane, 3 (4), 8 (9) -di (isocyanate
Natemethyl) tricyclo [5,2,1,0^2,6] Big
3 (4), 8 (9) -di (isocyanatoethyl)
Tricyclo [5,2,1,0^2,6] Decane, 3 (4)-
Isocyanatemethyl-8 (9) -isocyanateethyl
Rutricyclo [5,2,1,0^2,6] Decane, 4, 9
(10) -diisocyanatomethyltetracyclo (6,
2,1,1^3,6, 0^2,7) Dodecane, 4 (5), 9 (1
0) -diisocyanatomethyltetracyclo (6,2
2,1^3,6, 0^2,7) Tridecane, more preferably
2,5 (6) -di (isocyanatomethyl) bicyclo
[2,2,1] heptane, 2,5 (6) -di (isocyanate
Ethate) bicyclo [2,2,1] heptane, 3
(4), 8 (9) -di (isocyanatomethyl) tricy
Black [5,2,1,0^2,6] Decane, 3 (4), 8
(9) -di (isocyanatoethyl) tricyclo [5,
2,1,0^2,6Decane, particularly preferably 2,5
(6) -di (isocyanatomethyl) bicyclo [2,
2,1] heptane, 3 (4), 8 (9) -di (isocyanate
Natemethyl) tricyclo [5,2,1,0 ^2,6] Big
Is used. These may be used alone or optionally.
Used in combination.

In the present invention, the isocyanate is modified with an alkylene oxide adduct of a polyvalent amine. The polyamine used in the production of the alkylene oxide adduct of a polyamine is a compound having two or more amino groups, and a known compound can be used. Specific examples include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, and the like.

Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, butyl glycidyl ether, phenyl glycidyl ether, allyl glycidyl ether and the like. Preferred are ethylene oxide, propylene oxide, butylene oxide and styrene oxide, and more preferred are ethylene oxide, propylene oxide and butylene oxide. These may be used alone or in any combination. An appropriate amount of the alkylene oxide to be used is 4 to 24 mol per 1 mol of the polyamine. Preferably, 8 to 24 moles, more preferably, 8 to
It is 20 mol, particularly preferably 8 to 18 mol.

The alkylene oxide adduct of a polyvalent amine can be produced by a known method. For example, only a polyamine or a polyamine and a catalytic amount of an amine are charged to an autoclave, replaced with dry nitrogen, then heated to about 100 ° C., and under a reduced pressure, an arbitrary amount of alkylene oxide is added. The reaction can be carried out until the internal pressure does not decrease, and then unreacted alkylene oxide is removed.

The amount of the alkylene oxide adduct of a polyvalent amine used for modifying the polycyclic aliphatic diisocyanate is such that the OH group equivalent contained in the alkylene oxide adduct of the polyvalent amine is such that The NCO group equivalent contained in the group III diisocyanate is preferably about 0.01 to 0.5 equivalent, more preferably about 0.05 to 0.3 equivalent, particularly preferably about 0.1 to 0.1 equivalent. ~
It is an amount equivalent to 0.3 times the equivalent.

The polycyclic aliphatic isocyanate modified with an alkylene oxide adduct of a polyvalent amine can be produced by a known method. For example, a method in which an alkylene oxide adduct of a polyvalent amine and a polycyclic aliphatic diisocyanate are charged into a reaction vessel, replaced with dry nitrogen under stirring, and then heated to about 80 ° C. and reacted for about 2 hours. It can be manufactured by

The microcapsules for pressure-sensitive copying paper according to the present invention are preferably prepared by dissolving a polycyclic aliphatic isocyanate modified with the above-mentioned alkylene oxide adduct of a polyvalent amine and an electron-donating color former in a hydrophobic liquid. It is manufactured by emulsifying an internal phase containing a core substance in an aqueous phase, and then adding a polyvalent amine to form a synthetic resin film at a droplet interface to form a wall material of a microcapsule. In the production of the microcapsules for pressure-sensitive copying paper of the present invention by the interfacial polymerization method, first, a hydrophobic core substance in which an electron-donating color former is dissolved in a hydrophobic liquid is prepared, and the above-mentioned alkylene oxide addition of a polyvalent amine is performed. A polycyclic aliphatic isocyanate modified with the product is added to prepare the internal phase.

Next, the internal phase is formed by using polyvinyl alcohol, anion-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, polyvinylpyrrolidone, ligninsulfonic acid, polystyrenesulfonic acid, acrylic acid-acrylonitrile copolymer, acrylic acid-acrylonitrile-acrylamidomethylpropane. Sulfonic acid copolymer, carboxymethyl cellulose, gelatin, polyacrylic acid, acrylamide-acrylic acid copolymer, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, methyl vinyl ether-maleic anhydride copolymer , A naphthalenesulfonic acid-formalin condensate, and other protective colloids in an aqueous phase, and add a homomixer, homogenizer, ultrasonic homogenizer, Waring blender, Jet mixer, the emulsifier, such as an inline mill, to produce an emulsion of fine particles having an average particle diameter of 2 to 10 [mu] m. Then, after adding a polyvalent amine dissolved in water to the emulsion at room temperature, the mixture is kept at a temperature of 50 to 80 ° C. for 2 to 3 hours with stirring, whereby the pressure-sensitive copying paper microcapsule solution is obtained. can get.

The electron-donating color-forming agent used in the present invention includes phthalide derivatives, fluorane derivatives, azaphthalide derivatives, triphenylmethane derivatives, phenothiazine derivatives, indolylphthalide derivatives, leuco-olamine derivatives, spiropyran compounds, rhodamine lactam compounds. And leuco dyes such as benzoxazine compounds. Examples of the hydrophobic liquid used in the present invention include partially hydrogenated terphenyl, chlorinated paraffin, diarylalkane, alkylated naphthalene, and alkylated biphenyl. The amount of the electron-donating color former depends on the sensitivity of the color former,
Although it varies depending on the sensitivity of the developer, the conditions under which the pressure-sensitive copying paper is used, and the like, it is usually contained in the hydrophobic core material in about 1 to 10%, or in the internal phase in about 0.7 to 9%.

The polyvalent amine to be added to the emulsion is a compound having two or more amino groups, and known compounds can be used. Specific examples include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, and the like. These may be used alone or in any combination. The amount of the polyvalent amine used is such that the NH ₂ group equivalent contained in the polyvalent amine is based on the NCO group equivalent contained in the polycyclic aliphatic isocyanate modified with the alkylene oxide adduct of the polyvalent amine. Preferably, about 0.05 to
It is 1.0 equivalent, more preferably about 0.05 to 0.8 equivalent, particularly preferably about 0.1 to 0.7 equivalent.

The amount of the resin used in the reaction of the polycyclic aliphatic isocyanate modified with the alkylene oxide adduct of the polyvalent amine and the polyvalent amine with respect to the hydrophobic core substance is as follows:
1 to 100 parts by weight, preferably 3 to 50 parts by weight, more preferably 5 to 100 parts by weight, based on 100 parts by weight of the hydrophobic core material.
-30 parts by weight. The microcapsules obtained by forming a synthetic resin film by the reaction of the polycyclic aliphatic isocyanate modified with the alkylene oxide adduct of the polyamine and the polyamine thus obtained according to the present invention have a pressure resistance, It is a microcapsule for pressure-sensitive copying paper with excellent friction properties.

The microcapsules using a resin obtained by the reaction of the polycyclic aliphatic isocyanate modified with the polyvalent amine alkylene oxide adduct of the present invention and the polyvalent amine as a wall material are microcapsules for pressure-sensitive copying paper. In addition to capsules, leuco pigments, compounds having a phenolic hydroxyl group, temperature indicating materials containing alcohols in the same microcapsule, flavors, insecticides, fungicides, pesticides, fungicides,
It can also be used as a microcapsule of a lubricant, a liquid crystal, a hardener, a wax or the like.

[0024]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Production Examples, Examples and Comparative Examples, but the present invention is not limited thereto. Production Example 1 Production of Alkylene Oxide Adduct of Ethylenediamine 60.1 g (1.0 mol) of ethylenediamine was charged into a 2 L autoclave, and the autoclave was replaced with dry nitrogen. Under reduced pressure,
288 g (4.0 mol) of butylene oxide was gradually charged so that the internal pressure of the autoclave did not become 4 kg / cm ² or more. The temperature rose as the butylene oxide was charged. After charging is completed, internal pressure is 0.1kg / c
The reaction was carried out at 110 ° C. until it fell to m ² . Thereafter, the pressure was increased to ² kg / cm ² with dry nitrogen, and the reaction was continued at 110 ° C. until no decrease in the internal pressure of the autoclave was observed. The reaction time was 5 hours. After cooling, 3.0 g of potassium hydroxide was subsequently charged into the autoclave, and 727.2 g (10.1 mol) of butylene oxide was added under reduced pressure, and the internal pressure of the autoclave was changed to 4 kg / cm.
Charged gradually so as not to exceed ² . The temperature rose as the butylene oxide was charged. After charging,
The reaction was carried out at 110 ° C. until the internal pressure dropped to 0.1 kg / cm ² . Thereafter, the pressure was increased to ² kg / cm ^{2 with} dry nitrogen, and the reaction was continued at 110 ° C. until no decrease in the internal pressure of the autoclave was observed. The reaction time was 5 hours. After completion of the reaction, unreacted monomers are removed under reduced pressure, and neutralization and purification are carried out using 85% phosphoric acid. As a product, 1070 g of a butylene oxide adduct of ethylenediamine (butylene oxide is added to 1 mole of ethylenediamine with respect to 1 mol of ethylenediamine) 14 mol adduct) was obtained. This product was a colorless and transparent liquid, and no primary or secondary amine value was observed.

Production Example 2: Production of 2,5 (6) -di (isocyanatomethyl) bicyclo [2,2,1] heptane modified with an alkylene oxide adduct of ethylenediamine 4 mol of propylene oxide per 1 mol of ethylenediamine 125 g of an adduct obtained by adding 5 mol of ethylene oxide, 2,5 (6) -di (isocyanatomethyl)
1030 g of bicyclo [2,2,1] heptane was charged into a 2 L reactor, and the mixture was purged with dry nitrogen under stirring. The internal temperature of the reactor was raised to 80 ° C., and the reaction was carried out for 2 hours.
2,5 (6) -di (isocyanatomethyl) bicyclo [2,2,1] heptane modified with propylene oxide and ethylene oxide adduct of ethylenediamine (OH group equivalent of alkylene oxide adduct of polyamine /
NCO group equivalent of polycyclic aliphatic diisocyanate = 0.
1) was obtained. This product is a pale yellow transparent liquid, N
The CO group content was 31.1 wt%.

Example 1 Crystal violet lactone (CVL) as a dye
Synthesis Example 2 was added to 100 g of phenylxylylethane (4.0 g of dissolved phenylxylylethane (Nippon Petrochemical Co., Ltd. [SAS-296])).
Propylene oxide of ethylenediamine produced by
2,5 (6) modified with an ethylene oxide adduct (an adduct obtained by adding 4 mol of propylene oxide and 5 mol of ethylene oxide to 1 mol of ethylenediamine)
-Di (isocyanatomethyl) bicyclo [2,2,1]
18.9 g of heptane (OH group equivalent of alkylene oxide adduct of polyvalent amine / NCO group equivalent of polycyclic aliphatic diisocyanate = 0.1) (-NCO 0.14 equivalent)
Was dissolved. This internal phase was gradually added to 110 g of water in which 5.0 g of polyvinyl alcohol (Kuraray “PVA-205”) was dissolved by using a homomixer (manufactured by Tokushu Kika Co., Ltd.) at a rotation speed of 4000 rpm. After mixing and emulsification, an emulsion having an average particle diameter of 6 μm was obtained after 7.5 minutes. Under stirring, 1.80 g of ethylenediamine (-N
H ₂ 0.06 eq) was added dropwise little by little an aqueous solution prepared by dissolving in water 120 g. After completion of the dropwise addition, the mixture was stirred at room temperature for 30 minutes, and the temperature of the reaction system was raised to 70 ° C., and the reaction was performed for 2 hours.
A 6% microcapsule solution 359 for pressure-sensitive copying paper was prepared.

The obtained microcapsule liquid was evaluated according to the following performance test method. The performance evaluation test results are shown in Table 1 (Table 1). (1) Preparation of upper paper: 140 g of a microcapsule solution for pressure-sensitive copying paper having a solid content of 36% by weight was added with an average particle diameter of 15 to
20 g of 20 μm flour starch, 12 g of 50% by weight styrene butadiene latex and 580 g of water were added to prepare a mixed microcapsule coating liquid. ^On a high quality paper of 40 g / m ^2, the coating amount of the capsule coating liquid is 2.2 g / m ^2.
Was applied using a Mayer bar and dried at 105 ° C. for 30 seconds to produce an upper sheet for pressure-sensitive copying paper. (2) Color development performance test: The coated surface of the upper paper prepared in (1) and the coated surface of the lower paper (Mitsubishi N-40) were matched.
At a temperature of 23 ° C., the color is developed by passing through a calender with a linear pressure of 50 kg / cm. The reflectivity of the coated surface of the lower sheet 24 hours after color development is measured with a # 80 color difference meter, and is displayed as a Y value. (3) Microcapsule pressure resistance test (pressure contamination):
The coated surface of the upper paper prepared in (1) and the coated surface of the lower paper (Mitsubishi Paper N-40) were combined, and at a temperature of 23 ° C., 20 kg / cm with a Mullen burst tester (manufactured by Toyo Seiki Co., Ltd.).
^Under the conditions of ² , pressurize for 1 minute. One hour later, the reflectance of the lower paper coated surface is measured with a # 80 color difference meter, and the difference from the reflectance of the uncolored portion of the lower paper coated surface is determined. The smaller the difference, the better the pressure resistance (pressure contamination). (4) Friction resistance test (friction contamination property) of microcapsules: coated surface (10 × 2.5) of upper paper prepared in (1)
cm) and the coated surface of the lower paper (Mitsubishi Paper N-40) (30
× 3 cm), and rubbed at a temperature of 23 ° C. with a friction tester for dye fastness (manufactured by Toyo Seiki Co., Ltd.) under a load of 200 g and reciprocating five times. One hour later, the reflectance of the coated surface of the lower sheet is measured with a # 80 color difference meter. Since the measurement portion has a variation in the state of contamination, measurement is performed at three locations per sample, and the difference from the reflectance of the uncolored portion of the coated surface of the lower sheet is determined. The smaller the difference, the better the friction resistance (friction contamination).

Example 2 In Example 1, as the polycyclic aliphatic diisocyanate modified with an alkylene oxide adduct of a polyvalent amine, propylene oxide of ethylenediamine, an ethylene oxide adduct (1 mole of ethylenediamine,
2,5 modified with 7.8 mol of propylene oxide and 9.9 mol of ethylene oxide)
(6) -di (isocyanatomethyl) bicyclo [2,
2,1] heptane 17.9 g (OH group equivalent of alkylene oxide adduct of polyamine / NCO group equivalent of polycyclic aliphatic diisocyanate = 0.1, -NCO 0.12
(Equivalent), a microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 1, and a performance evaluation test was conducted in the same manner as in Example 1. Table 1 shows the performance evaluation test results.

Example 3 In Example 1, the polycyclic aliphatic diisocyanate modified with an alkylene oxide adduct of a polyamine was used as a propylene oxide or ethylene oxide adduct of ethylenediamine (1 mol of ethylenediamine with respect to 1 mol of ethylenediamine).
2,5 modified with 7.8 mol of propylene oxide and 9.9 mol of ethylene oxide)
(6) -di (isocyanatomethyl) bicyclo [2,
2,1] heptane 19.4 g (OH group equivalent of polyalkylene oxide alkylene oxide adduct / NCO group equivalent of polycyclic aliphatic diisocyanate = 0.2, -NCO 0.10
(Equivalent), a microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 1, and a performance evaluation test was conducted in the same manner as in Example 1. Table 1 shows the performance evaluation test results.

Example 4 In Example 1, 2.58 g of diethylenetriamine (0.05 equivalent of -NH ₂ ) was used instead of ethylenediamine.
A microcapsule solution for pressure-sensitive copying paper was manufactured in the same manner as in Example 1 except that the above was used, and a performance evaluation test was performed in the same manner as in Example 1. Table 1 shows the performance evaluation test results.

Example 5 In Example 2, 1,1 was used instead of ethylenediamine.
3-propylene diamine 1.48 g (-NH ₂ 0.04
A microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 2 except that the equivalent weight was used, and a performance evaluation test was conducted in the same manner as in Example 2. Table 1 shows the performance evaluation test results.

Example 6 In Example 1, diisopropylnaphthalene [Kureha Chemical Co., Ltd.] was used instead of phenylxylylethane [SAS-296] of Nippon Petrochemical Co., Ltd. as the hydrophobic liquid.
[KMC-113]] A microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 1 except that 100 g of the same was used, and a performance evaluation test was carried out in the same manner as in Example 1. Table 1 shows the performance evaluation test results.

Example 7 In Example 2, a homomixer (manufactured by Tokushu Kika Co., Ltd.) was used.
Instead of using a homodisper (manufactured by Tokushu Kika Co., Ltd.), a microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 1 except that the mixture was emulsified at 7,400 rpm for 15 minutes. A performance evaluation test was performed in the same manner as in Example 2. Table 1 shows the performance evaluation test results.

Comparative Example 1 In Example 1, the modified 2,5 (6) -di (isocyanatemethyl) bicyclo [2,2,1] heptane was replaced with the unmodified 2,5 (6) -di (isocyanate A microcapsule solution for pressure-sensitive copying paper was prepared in the same manner as in Example 1 except that methyl) bicyclo [2,2,1] heptane was used, and a performance evaluation test was performed in the same manner as in Example 1. . Table 1 shows the performance evaluation test results.

Comparative Example 2 A microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 1 except that ethylenediamine was not used, and a performance evaluation test was conducted in the same manner as in Example 1. Was done. Table 1 shows the performance evaluation test results.

Comparative Example 3 Example 2 was modified with propylene oxide and ethylene oxide adduct of ethylenediamine (an adduct obtained by adding 4 mol of propylene oxide and 5 mol of ethylene oxide to 1 mol of ethylenediamine).
5 (6) -di (isocyanatomethyl) bicyclo [2,
Instead of 2,1] heptane, an adduct obtained by adding 4 mol of propylene oxide and 5 mol of ethylene oxide to 1 mol of ethylenediamine and 2,5 (6) -di (isocyanatomethyl) bicyclo [2,2,1 A microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 1 except that a mixture with heptane was used, and a performance evaluation test was performed in the same manner as in Example 1. Table 1 shows the performance evaluation test results.

Comparative Example 4 Example 2 was modified with propylene oxide and ethylene oxide adduct of ethylenediamine (an adduct obtained by adding 7.8 mol of propylene oxide and 9.9 mol of ethylene oxide to 1 mol of ethylenediamine). Instead of 2,5 (6) -di (isocyanatomethyl) bicyclo [2,2,1] heptane, 7.8 mol of propylene oxide is added to 1 mol of ethylenediamine,
An adduct obtained by adding 9.9 mol of ethylene oxide and 2,
5 (6) -di (isocyanatomethyl) bicyclo [2,
2,1] A microcapsule solution for pressure-sensitive copying paper was produced in the same manner as in Example 2 except that a mixture of heptane was used, and a performance evaluation test was carried out in the same manner as in Example 1. Table 1 shows the performance evaluation test results.

[0038]

[Table 1]

As shown in Table 1, the pressure-sensitive copying paper produced by using the microcapsule of the present invention, as can be seen from Examples 1 to 7, shows the density of undeveloped portion, the pressure resistance test, The difference in the friction test (reflectance) was very small as compared with Comparative Examples 1 to 4, indicating that the pressure resistance and the friction resistance were excellent. Further, as can be seen from Example 1 and Comparative Example 1, by using a modified system of the same polycyclic aliphatic diisocyanate as compared with a system using an unmodified polycyclic aliphatic diisocyanate, pressure resistance, A remarkable improvement in friction resistance is observed. As can be seen from Example 2 and Comparative Example 2, improvement in pressure resistance and friction resistance is observed by adding a polyvalent amine after emulsification, as compared with a system in which a polyvalent amine is not added. As can be seen from Example 1 and Comparative Example 3, and Example 2 and Comparative Example 4, as compared with the system using the polycyclic aliphatic isocyanate modified with the alkylene oxide adduct of the amine used in the present invention, the alkylene of the amine was reduced. In a system in which an alkylene oxide adduct of an amine and a polycyclic aliphatic diisocyanate were each dissolved in a hydrophobic core material without being previously modified with an oxide adduct, the color density, pressure resistance, and rub resistance were satisfied. It turns out that performance is not obtained. From Examples 1, 6, and 7, the pressure resistance, regardless of the core substance and the emulsifier,
It can be seen that microcapsules having excellent friction resistance can be obtained. The pressure-sensitive copying paper manufactured using the microcapsules manufactured by the method of the present invention has extremely excellent performance in pressure resistance and friction resistance, which are the drawbacks of microcapsules manufactured by the interfacial polymerization method. On the other hand, for the pressure-sensitive copying paper, the other performances were not inferior.

[0040]

The pressure-sensitive copying paper produced by using the microcapsules of the present invention does not decrease the color density and exhibits extremely excellent pressure resistance and friction resistance.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kozo Tanaka 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Mitsui Toatsu Chemicals Co., Ltd.

Claims (1)

[Claims] An emulsified internal phase containing a polyvalent isocyanate and a hydrophobic core substance in which an electron-donating color former is dissolved in a hydrophobic liquid is emulsified in an aqueous phase, and then a polyvalent amine is added. In a method for producing a microcapsule for pressure-sensitive copying paper in which a synthetic resin film is formed at a droplet interface, a polycyclic aliphatic diisocyanate represented by the following general formula (1) is used as a polyvalent isocyanate. (Where k is 1-2, j and m are 1-5, h is 0-2
Which is a polycyclic aliphatic isocyanate modified with an alkylene oxide adduct of a polyhydric amine).