WO1991012883A1 - Microcapsules thermo-et/ou photolabiles - Google Patents

Microcapsules thermo-et/ou photolabiles Download PDF

Info

Publication number
WO1991012883A1
WO1991012883A1 PCT/DE1991/000164 DE9100164W WO9112883A1 WO 1991012883 A1 WO1991012883 A1 WO 1991012883A1 DE 9100164 W DE9100164 W DE 9100164W WO 9112883 A1 WO9112883 A1 WO 9112883A1
Authority
WO
WIPO (PCT)
Prior art keywords
microcapsules
solution
groups
polycondensation
monomers
Prior art date
Application number
PCT/DE1991/000164
Other languages
German (de)
English (en)
Inventor
Oskar Nuyken
Jochen Dauth
Wolfgang Pekruhn
Original Assignee
Mannesmann Ag
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mannesmann Ag filed Critical Mannesmann Ag
Publication of WO1991012883A1 publication Critical patent/WO1991012883A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
    • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
    • B41M5/28—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using thermochromic compounds or layers containing liquid crystals, microcapsules, bleachable dyes or heat- decomposable compounds, e.g. gas- liberating
    • B41M5/287—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using thermochromic compounds or layers containing liquid crystals, microcapsules, bleachable dyes or heat- decomposable compounds, e.g. gas- liberating using microcapsules or microspheres only
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/02—Making microcapsules or microballoons
    • B01J13/06—Making microcapsules or microballoons by phase separation
    • B01J13/14—Polymerisation; cross-linking
    • B01J13/16—Interfacial polymerisation
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/002—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor using materials containing microcapsules; Preparing or processing such materials, e.g. by pressure; Devices or apparatus specially designed therefor

Definitions

  • the invention relates to microcapsules, the polymeric capsule wall of which has thermo- and / or photolabile groups as structural elements, and a method for their production.
  • Microcapsules with a polymeric capsule wall processes for their production and various possible uses are known from "Angewandte Chemie", 1975, pages 556 to 567. These include hollow polymer particles with a size of approx. 1 ⁇ m to several millimeters, which consist for example of a core and a solid capsule wall.
  • the core of such a microcapsule can contain, for example, an active substance which is isolated from the environment by the capsule wall. By targeted action on the capsule wall, it can now be destroyed or made porous and permeable. The contents of the capsule come out and can have an effect there.
  • the capsule can be opened mechanically from the outside, for example by shearing or crushing, thermally by melting or burning the capsule wall, from the inside, for example by heating the capsule content above the boiling point and by dissolving it in a liquid medium.
  • microencapsulation of active substances include interfacial polycondensation, in which the two reactants forming the polymer are contained in two different liquids which are not miscible with one another, and a dispersion of one liquid phase in the other with a desired particle diameter is produced before the polycondensation. This is done, for example, in a water dispersant solution with vigorous stirring. The reaction then begins at the interface of the dispersed droplets, forming a capsule wall that encloses the droplet itself inside.
  • a known use of microcapsules is that of reaction writing papers, for example of the "self-contained type". These papers are coated with microcapsules that are filled with a color former. Furthermore, the coating contains a developer substance that immediately produces a visible color reaction with the color former through the printing of a writing instrument and thus represents a kind of ink contained in the paper.
  • microcapsules filled with ink are applied to a recording medium and are "exposed" with a laser beam in accordance with the image to be recorded, the capsule wall being broken open or at least made permeable to the ink. In a manner not described, the ink then reaches the recording paper and forms an image corresponding to the recording there. There is also no description of how such microcapsules could be produced or which materials would be suitable for this.
  • peroxide groups -0-0-
  • microcapsules according to claim 1 It is an object of the present invention to improve such microcapsules with capsule wall polymers containing azo groups and to provide new azo monomers for their preparation. This object is achieved by microcapsules according to claim 1. Further refinements of the invention can be found in subclaims 2 to 6 and a method for producing the microcapsules in claims 7 to 11.
  • the microcapsules according to the invention are distinguished by a novel chemical structure of the capsule wall or of the polymer used for this.
  • the polyfunctional azo group-containing monomers, or those having more than two reactive groups, represent linking points in the condensed polymer.
  • the invention provides a thermo- and / or or photolabile microcapsule with increased crosslinking density of the capsule wall polymer.
  • a higher crosslinking of the capsule wall in turn improves the thermal mechanical properties of the polymer and allows the display of a denser capsule wall with which the preferably liquid content of the microcapsule is better retained or
  • the degree of crosslinking also influences the glass transition temperature T G and the hardness of the polymer.
  • the polycondensation according to the invention results in polymers with a fundamentally different chain structure.
  • Polymers can be formed in which the azo group is not contained in the main chain, but instead represents the link between two polymer chains. If reactants with only two correspondingly reactive groups are used to produce the polycondensate, a crosslinked polymer is formed which could have thermoplastic properties above the decomposition temperature of the azo group or of the polymer containing the azo group, provided that the radicals formed during the decomposition do not produce partial crosslinking of the polymer chain again.
  • the capsule wall can be made thinner with at least constant thermal-mechanical properties.
  • a thinner capsule wall in turn allows the microcapsules to respond more quickly if the capsule contents are to be released by exceeding the decay temperature. This is particularly important for those microcapsules that are used with dye in thermal printing processes.
  • a better "response" of the microcapsules in thermal printing requires less energy transfer and results in an improved printed image.
  • the invention also makes new azo groups
  • Monomers are made available which open up a wider spectrum of possible properties, in particular possible decomposition temperatures, during the production of the microcapsules themselves.
  • Another advantage of the microcapsules according to the invention can be seen in the decay energy which is released during the thermolysis or photolysis of the azo group. This energy, which occurs in particular as heat, supports the release of the capsule contents, so that less energy has to be used for this.
  • molecular nitrogen, ie a gas is released during the decomposition, which could mechanically support the further opening of the capsule wall or the release of the capsule contents.
  • the polymers of the microcapsules according to the invention can be set to decomposition temperatures of about 120 to 250 ° C. This guarantees that there is no risk of premature decomposition during transport or storage, and the microcapsules are therefore stable and stable for a long time.
  • the capsule wall polymers are completely insoluble in relation to organic solvents, so that there is no risk of decomposition from the inside even with liquid capsule contents.
  • the properties of the capsule wall are of course also dependent on the type of polymer which is produced by polycondensation or polyaddition.
  • the size of the residues bound to the azo group and the size of the reactants can be used to regulate the number of azo groups contained in the polymer per unit weight, which are decisive as breaking points for breaking open the capsule wall.
  • a further possibility of variation of the capsule wall polymers can be set by copolymerizing the azomonomers with additional thermostable and photostable starting monomers. The process for producing the microcapsules is explained in more detail below with reference to two figures which represent two different process stages.
  • FIG. 3 shows a coated film as an application example.
  • Solution containing dispersant can form a single phase with one of the two preceding solutions.
  • the type of dispersant which is also referred to as a protective colloid, also determines which of the two phases in the Dispersion to the "solvent" is also called liquor, or which of the two phases represents the continuum or the later capsule content.
  • the active ingredient to be encapsulated is added to the continuum before the onset or initiation of the polycondensation, while the dispersant is usually dissolved in the liquor.
  • a dispersion 1 is prepared from the dispersant and the solution of one of the two reactants with vigorous stirring.
  • high stirring speeds of more than 1000 revolutions per minute are required.
  • turbo stirrer is well suited for laboratory-scale approaches.
  • the stirring speed determines the fineness of the dispersion or the size or diameter of the droplets 3 floating in the liquor 2, which represent the continuum.
  • Figure 2 The solution of the second reaction partner is now added slowly and with stirring to the dispersion, the polycondensation beginning at the phase interfaces between the liquor and the continuum. Due to the high reactivity of the compounds involved, the reaction takes place completely at room temperature. After the addition is complete, stirring is continued for about 1/2 hour.
  • the finished microcapsules 5 are usually processed further as a solution and can be used, for example, to produce a reaction writing paper.
  • FIG. 3 The coating of a film 6 with the microcapsules 5 according to the invention is particularly simple. If, for example, polyvinyl alcohol is used as a protective colloid, the microcapsules 5 produced can be applied directly to the carrier film as an aqueous solution.
  • the dispersant acts as a binder and produces an abrasion-resistant film 7. Not only liquids can be encapsulated with the described method, but also suspensions. For this purpose, instead of the solution forming the continuum, a suspension of the corresponding solid is generated in the solvent.
  • a dispersion is produced with the second solvent or the second phase, the solid remains in the original phase, thus passes into the continuum and is therefore completely encapsulated in the interfacial polycondensation. For this variant, no change in the process parameters and no other dispersant is required.
  • PVA polyvinyl alcohol
  • microcapsule suspension is stirred for about 30 minutes to complete the interfacial polycondensation.
  • the microcapsule dispersion is mixed together with silica gel as the developer, cellulose powder as a spacer and flow agent, and polyvinyl alcohol as a binder and applied to a support (film or paper).
  • the capsules are thermolytically broken open at 120 to 140 ° C by thermal addressing, for example by means of a thermal print head.
  • the color former (KVL) emerges from the addressed microcapsules and creates a blue marking on the carrier.
  • the microcapsules can also be broken open photolytically with the aid of a laser with a wavelength of approximately 350 to 400 nm.
  • the font width that can be achieved is less than 2 mm.
  • corresponding microcapsules with an analogous structure can be produced by varying the reactive multifunctional component, for example in the form of di-, tri- or multifunctional amines or alcohols.
  • the NaOH contained in the aqueous phase serves to neutralize the acid HCl formed.
  • a slightly modified process requires azo-containing monomers with amino and alcohol functions as reactive groups.
  • the amino groups into ammonium salts, for example the corresponding hydrochlorides or converting the alcohols into corresponding alcoholates, the monomers become soluble in the aqueous phase and can be reacted with those reactive compounds which are soluble in the organic phase in the interfacial polycondensation. If the dispersant remains the same, the assignment of
  • microcapsules the polymeric capsule wall of which has thermo- and / or photolabile groups as structural elements.
  • azo group-containing monomers presented by way of example, microcapsules can be produced by interfacial polycondensation with correspondingly reactive multifunctional compounds, the capsule wall of which can consist of a number of different types of polymer.
  • the crosslinking density of the polymers can be influenced by polyfunctional azomonomers and polyfunctional reaction partners. It is therefore possible to produce microcapsules whose relatively thin capsule wall is impervious to any capsule content, in particular an organic solvent, at normal temperatures. When the settable decomposition temperature is reached, the capsule wall polymers disintegrate in an exothermic reaction, whereby molecular nitrogen is split off from the azo groups. The capsule contents are thus released with relatively little energy expenditure.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Optics & Photonics (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing Of Micro-Capsules (AREA)

Abstract

L'invention concerne des microcapsules dont la paroi polymère présente des groupes thermo-et/ou photolabiles en tant qu'éléments structuraux, produits par polycondensation à l'interface de monomères porteurs de groupes azoïques avec des composés plus fonctionnels sur le plan réactif avec formation de polyamides, polycarbonates, polyesters, polycarbamides ou polyuréthane.
PCT/DE1991/000164 1990-03-02 1991-02-22 Microcapsules thermo-et/ou photolabiles WO1991012883A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP4006612.6 1990-03-02
DE4006612 1990-03-02

Publications (1)

Publication Number Publication Date
WO1991012883A1 true WO1991012883A1 (fr) 1991-09-05

Family

ID=6401297

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1991/000164 WO1991012883A1 (fr) 1990-03-02 1991-02-22 Microcapsules thermo-et/ou photolabiles

Country Status (2)

Country Link
EP (1) EP0516712A1 (fr)
WO (1) WO1991012883A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8865030B2 (en) 2008-03-11 2014-10-21 Basf Se Microcapsules having a radiation-induced or thermal release
EP3115348A1 (fr) * 2015-07-07 2017-01-11 BAE Systems PLC Composition explosive coulée
WO2017006110A1 (fr) * 2015-07-07 2017-01-12 Bae Systems Plc Composition explosive à couler
US11186528B2 (en) 2015-07-07 2021-11-30 Bae Systems Plc PBX composition
US11278642B2 (en) 2006-09-08 2022-03-22 Takao Hotokebuchi Bioimplant with evanescent coating film

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1542260A1 (de) * 1965-03-05 1970-03-26 Keuffel & Esser Co Mit festem oder fluessigem Material gefuellte Kapseln
DE3918146A1 (de) * 1989-05-31 1990-12-06 Siemens Ag Mikrokapseln mit einer polymeren kapselwand

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1542260A1 (de) * 1965-03-05 1970-03-26 Keuffel & Esser Co Mit festem oder fluessigem Material gefuellte Kapseln
DE3918146A1 (de) * 1989-05-31 1990-12-06 Siemens Ag Mikrokapseln mit einer polymeren kapselwand

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11278642B2 (en) 2006-09-08 2022-03-22 Takao Hotokebuchi Bioimplant with evanescent coating film
US8865030B2 (en) 2008-03-11 2014-10-21 Basf Se Microcapsules having a radiation-induced or thermal release
EP3115348A1 (fr) * 2015-07-07 2017-01-11 BAE Systems PLC Composition explosive coulée
WO2017006110A1 (fr) * 2015-07-07 2017-01-12 Bae Systems Plc Composition explosive à couler
US11001540B2 (en) 2015-07-07 2021-05-11 Bae Systems Plc Cast explosive composition
US11186528B2 (en) 2015-07-07 2021-11-30 Bae Systems Plc PBX composition
US11746069B2 (en) 2015-07-07 2023-09-05 Bae Systems Plc PBX composition
US11753353B2 (en) 2015-07-07 2023-09-12 Bae Systems Plc PBX composition

Also Published As

Publication number Publication date
EP0516712A1 (fr) 1992-12-09

Similar Documents

Publication Publication Date Title
DE2652875C2 (de) Verkapselungsverfahren für die Herstellung von Mikrokapseln
EP0727251B1 (fr) Microcapsules à paroi constituée par des produits de réaction de polyisocyanates et quanidines
DE69102531T2 (de) Mikrokapseln, Verkapselungsverfahren und Methode zur Anwendung derselben.
EP0321750B2 (fr) Procédé de fabrication de microcapsules, les microcapsules ainsi préparées et leur utilisation
DE69203509T2 (de) Mikrokapseln aus polyfunktionellen Aziradinen.
EP0532462B1 (fr) Conditionnement de pesticides sous la forme de microcapsules
DE2527154A1 (de) Verfahren zur herstellung von oel enthaltenden mikrokapseln
DE69120772T2 (de) "Self-contained" Drucktinte, die viel Feststoff enthält
DE2417297A1 (de) In sich geschlossenes, unabhaengiges, druckempfindliches aufzeichnungssystem und verfahren zu seiner herstellung
DE60312603T2 (de) Mikrokapsel und Verfahren zu deren Herstellung
DE2634789C2 (de) Verfahren zur Herstellung von druckempfindlichen Schreibflächen mit einem Farbvorläufer in Mikroverkapselung
DE69107265T2 (de) CB-Drucktinten zur Herstellung einer schwarzen Abbildung.
WO1991012883A1 (fr) Microcapsules thermo-et/ou photolabiles
DE2617747C2 (de) Reaktionsdurchschreibepapiere
DE69918705T2 (de) Cb-drucktinten
DE69702404T2 (de) Mehrfarbiges wärmeempfindliches Aufzeichnungsmaterial
EP0516742B1 (fr) Microcapsules contenant une phase aqueuse
EP0532463B1 (fr) Conditionnement de pesticides
DE2307665A1 (de) Verfahren zum herstellen kleiner polymerkapseln
EP0283711A1 (fr) Procédé de microencapsulation d'huiles hydrophobes, les microcapsules et leur application
DE4006570C1 (fr)
DE69502409T2 (de) Verfahren zur herstellung von mit duftstoffen gesättigten oder beschichteten mikroverkapselten trägern
DE4225863A1 (de) Wärmeempfindliche Aufzeichnungsmaterialien mit polymerumhülltem Entwicklungshilfsmittel
DE3918141A1 (de) Mikrokapseln mit einer polymeren kapselwand
WO1990014883A1 (fr) Microcapsules a paroi polymere

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU NL SE

WWE Wipo information: entry into national phase

Ref document number: 1991905095

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1991905095

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1991905095

Country of ref document: EP