Patrick Gane - Academia.edu (original) (raw)
Papers by Patrick Gane
Tappi Journal, 1986
La production actuelle de pepier couche implique l'utilisation d'un large domaine de tech... more La production actuelle de pepier couche implique l'utilisation d'un large domaine de techniques et produits specialises, dont beaucoup controlent les aspects de la structure de la couche
Coating shrinkage upon drying is a phenomenon well known to the paper coating industry where it o... more Coating shrinkage upon drying is a phenomenon well known to the paper coating industry where it often causes changes in the final structure of the coating layer, leading to poor results in terms of gloss, light scattering, surface strength, coverage and printability. The aim of this paper is to improve the understanding of coating shrinkage by measuring the forces related to the capillarity, acting at the free liquid front, in combination with the flocculation, film forming and compressibility characteristics of the coating structure and binders. Shrinkage while the coating layer dries has been successfully measured by observing the deflection of coated strips of a dimensionally stable synthetic substrate. Ground calcium carbonate was used as the coating pigment together with latex binders of low and high Tg latex, respectively, and using starch additionally as an example of a natural film-forming binder. The final dry coatings were analysed with mercury porosimetry and by scanning ...
The absorption rate of flexographic ink fluids into porous pigmented structures has been measured... more The absorption rate of flexographic ink fluids into porous pigmented structures has been measured based on the methods of Gane, Schoelkopf, Spielmann, Matthews and Ridgway (2000). Identification of a preferred network pathway for absorption of low density, low viscosity fluids according to Schoelkopf, Gane, Ridgway and Matthews (2000) allows for correlation to be made between the shortterm rate of absorption into a network structure of a coating layer and the observed rate of imbibition into compressed porous block samples of coating pigment. The work extends this correlation from the idealised homogeneity of well-characterised fluids to the removal of a fluid phase formulation, consisting predominantly of water and additives, such as surfactant polymers, from commercial flexographic ink. The ink fluid phase is removed by the absorptive forces of the porous coating network acting against potential surface retardation structures forming at the interface between progressively concentr...
Evolution of surface improvements on paper are driven by technical needs, in respect of printing ... more Evolution of surface improvements on paper are driven by technical needs, in respect of printing and writing, economical drivers, such as mineral versus fibre cost and market niche exploitation, runnability and aesthetic requirements. From the simple antifeathering absorption control of hydrophobisers, such as starch, to the sophistication of digital printing, the need to modify the surface of paper is an accepted criterion for investment in our industry. Simple pond and roll application has, through increases in speed and the application of pigmentising, developed in recent times to controlled film application processes. The demands throughout these developments for the scientific understanding of the interactional processes between fluids and substrate: absorption, hydraulic penetration, basepaper fibre debonding and roughening: and the complex rheology of pigment suspensions, based on stability, surface chemical and hydrodynamic criteria, have usually been met retrospectively. Th...
Tappi Journal, 1997
X-ray diffraction techniques study the orientation of anisometric kaolin pigment particles in pap... more X-ray diffraction techniques study the orientation of anisometric kaolin pigment particles in paper coatings. Relationships between coating color solids, application geometry, and machine speed determine the degree of pigment particle alignment resulting from the dynamic separation mechanisms of the application method. Controlling blade configuration and coating color properties can optimize structural alignment in the coating layer. Roll coatings at high pigments solids concentrations develop disordered particle orientations. There is a distinct correlation between pigment particle alignment, runnability, and sheet gloss down to the microroughness limits of optical sensitivity and with offset print gloss and rotogravure printability throughout the complete orientational range. Premetering in a shear field enhances the potential orientational optimization in blade coating. Application : there is a direct correlation between the dried microstructure of a coating and the dynamic appli...
Enhancement of image quality and reduction in print-through can be achieved by printing on so-cal... more Enhancement of image quality and reduction in print-through can be achieved by printing on so-called Value Added Coldset (VAC) papers. Independent absorption tests, model coatings, commercial ink and paper samples, together with commercial printing trials, are used to illustrate the effect of pore structure and size distribution on the rate of absorption and the relative permeability of papers and coatings on the deposit build-up tendency. This work shows that runnability of specific ink and paper combinations is not a simple function of tack rate but rather a function of ink component penetration properties, specific for different surfaces, and its effect on ink adhesion in relation to permeability of the coating to fountain solution. This relates to the ability of the ink to be compatible with the fountain solution being used and the role of the basepaper in absorbing and retaining fountain solution. By developing a special tack measurement technique for coldset web offset (CSWO) ...
This paper discusses novel methods for observing the spreading and penetration behaviour of fluid... more This paper discusses novel methods for observing the spreading and penetration behaviour of fluids into specially prepared consolidated blocks of paper coating pigments which allows for the equilibrium absorption of measurable droplet sizes without saturation of the pigment layer. The mechanisms studied are responsible for a range of printing phenomena. Variables such as particle size distribution, pigment surface treatment with dispersing agents and the applied pressure during consolidation of the structure give the possibility to create a wide range of porous structures with differing structure-property relationships. By bringing liquids of differing polarity, surface tension and viscosity, stained and unstained, into contact with these porous blocks, either as a super source or in droplet form, the relevant phenomena of spreading, penetration and adsorption can be studied using image analysis techniques. Droplet absorption and pressureless fluid imbibition methods are contrasted ...
Tappi Journal, 1991
On examine les effets de la pâte a papier sur la structure du couchage, la couverture et la rugos... more On examine les effets de la pâte a papier sur la structure du couchage, la couverture et la rugosite de la feuille revetue a l'aide de techniques optiques de formation d'image. On compare les resultats obtenus avec des feuilles de pâte mecanique, de pâte thermomecanique et de pâte mecanique sous pression.
Wochenblatt Fur Papierfabrikation, 1991
On etudie les effets des variations de la geometrie de l'ecoulement dans la region proche de ... more On etudie les effets des variations de la geometrie de l'ecoulement dans la region proche de la lame en amont. On montre que l'on peut controler l'orientation de particules anisometriques, telles que celles de kaolin, en optimisant la geometrie de la lame et/ou la teneur en solides du couchage. On presente des exemples d'utilisation de ces effets pour le developpement de la structure de couchage la plus appropriee pour une application particuliere
Liquid–solid interactions are important for numerous natural and industrial processes in agricult... more Liquid–solid interactions are important for numerous natural and industrial processes in agriculture, coating, filtration, painting and printing. Understanding the effects of sequential absorption of oil components and water, in various arrangements, on porous coatings during the very short time it takes for a paper to pass through a printing machine is a prerequisite for a successful printing operation. Phenomena in the printing nip occur under far from equilibrium conditions, and therefore the interactions of liquids with the coating should also be studied in nonequilibrium conditions. When a droplet of liquid is placed on a surface its spreading is controlled by the balance of driving and resisting forces. The driving force for initial impact spreading is kinetic energy of the droplet, whereas flow resistance is provided by viscosity and surface tension of the liquid. As the kinetic energy of the impact dissipates, the wetting forces become important. Spreading of a liquid on a s...
The colorants, Fat Red Bluish (FRB) and Fat Blue B01 (FB), were investigated as potential image e... more The colorants, Fat Red Bluish (FRB) and Fat Blue B01 (FB), were investigated as potential image enhancers for paper cross sectioning by premixing directly into the embedding resin. One-side triple coated board samples were embedded using three commonly employed epoxy resins using this technique. Sections taken from the embedment were mounted respectively using immersion oil, Euparal®, and Glycerol 87 % solution. Under the light microscope excellent differentiated images with overall coloration of the whole cross-section were achieved. The degree of resin penetration could be clearly identified and the quality of cross-sections improved in respect to contrast and image definition. In this way, colorants can be used to improve well-established embedding techniques, such as the choice of resin, developing a higher quality of microscopic image, a reduction of preparation time for cross-sections etc. It may also be applied to improve or even define the contrast of cross-sections of commo...
On a developpe un modele mathematique qui decrit les effets dynamiques du couchage par lame sur l... more On a developpe un modele mathematique qui decrit les effets dynamiques du couchage par lame sur la sauce de couchage et la feuille support. On montre que l'application de poids de couche eleves permet de reduire la pression de la lame et l'angle en amont. Le brillant maximal est obtenu pour de plus faibles teneurs en solides. La reciproque est vraie lorsqu'on utilise de plus faibles poids de couche
Molecular Crystals and Liquid Crystals, 1981
The crystal and molecular structure of N-(4-n octyloxybenzylidene)-4'-butylaniline (80.4), C... more The crystal and molecular structure of N-(4-n octyloxybenzylidene)-4'-butylaniline (80.4), C25H35NO, has been determined at room temperature partially by direct methods and completed by subsequent Fourier synthesis. The crystals belong to the triclinic system with space group P1, a=5.452(3), b=7.948(4), c=27.356(4) Å, α=90.83(2), β=86.43(2) and γ=108.14(2)[ddot] with two molecules per unit cell. The structure consists of interdigitated sheets of molecules with alternate sheets in an head-to-tail configuration and displaced in the direction of the long molecular axes so as to give interdigitation of alkyl tails and of cores plus alkoxy tails. It is shown that the superficially very different structure of the homologue 40.8 may be described in a similar way. In neither case is there a close relation with the structure of the liquid crystal phase found in melting.
Molecular Crystals and Liquid Crystals, 1983
Detailed X-ray diffraction studies of bis-(4'-n-heptyloxybenzylidene)-1,4-phenylenediamine (... more Detailed X-ray diffraction studies of bis-(4'-n-heptyloxybenzylidene)-1,4-phenylenediamine (HEPTOBPD) have led to a positive phase identification, subsequently given confirmation by texture and miscibility studies. No new smectic liquid crystal phases, but two disordered crystal phases (J and K) are found which are analogous to G and H phases except for the direction of tilt.
Molecular Crystals and Liquid Crystals, 1981
Abstract The question of which of the known smetic phases exhibitis long range 3 dimensional orde... more Abstract The question of which of the known smetic phases exhibitis long range 3 dimensional order is first discussed briefly, The major theme of the paper is the nature of the structure and correlations in SB, SF, and S1 phases. Results are presented about the ...
Chemischer Informationsdienst, 1983
Tappi Journal, 1986
La production actuelle de pepier couche implique l'utilisation d'un large domaine de tech... more La production actuelle de pepier couche implique l'utilisation d'un large domaine de techniques et produits specialises, dont beaucoup controlent les aspects de la structure de la couche
Coating shrinkage upon drying is a phenomenon well known to the paper coating industry where it o... more Coating shrinkage upon drying is a phenomenon well known to the paper coating industry where it often causes changes in the final structure of the coating layer, leading to poor results in terms of gloss, light scattering, surface strength, coverage and printability. The aim of this paper is to improve the understanding of coating shrinkage by measuring the forces related to the capillarity, acting at the free liquid front, in combination with the flocculation, film forming and compressibility characteristics of the coating structure and binders. Shrinkage while the coating layer dries has been successfully measured by observing the deflection of coated strips of a dimensionally stable synthetic substrate. Ground calcium carbonate was used as the coating pigment together with latex binders of low and high Tg latex, respectively, and using starch additionally as an example of a natural film-forming binder. The final dry coatings were analysed with mercury porosimetry and by scanning ...
The absorption rate of flexographic ink fluids into porous pigmented structures has been measured... more The absorption rate of flexographic ink fluids into porous pigmented structures has been measured based on the methods of Gane, Schoelkopf, Spielmann, Matthews and Ridgway (2000). Identification of a preferred network pathway for absorption of low density, low viscosity fluids according to Schoelkopf, Gane, Ridgway and Matthews (2000) allows for correlation to be made between the shortterm rate of absorption into a network structure of a coating layer and the observed rate of imbibition into compressed porous block samples of coating pigment. The work extends this correlation from the idealised homogeneity of well-characterised fluids to the removal of a fluid phase formulation, consisting predominantly of water and additives, such as surfactant polymers, from commercial flexographic ink. The ink fluid phase is removed by the absorptive forces of the porous coating network acting against potential surface retardation structures forming at the interface between progressively concentr...
Evolution of surface improvements on paper are driven by technical needs, in respect of printing ... more Evolution of surface improvements on paper are driven by technical needs, in respect of printing and writing, economical drivers, such as mineral versus fibre cost and market niche exploitation, runnability and aesthetic requirements. From the simple antifeathering absorption control of hydrophobisers, such as starch, to the sophistication of digital printing, the need to modify the surface of paper is an accepted criterion for investment in our industry. Simple pond and roll application has, through increases in speed and the application of pigmentising, developed in recent times to controlled film application processes. The demands throughout these developments for the scientific understanding of the interactional processes between fluids and substrate: absorption, hydraulic penetration, basepaper fibre debonding and roughening: and the complex rheology of pigment suspensions, based on stability, surface chemical and hydrodynamic criteria, have usually been met retrospectively. Th...
Tappi Journal, 1997
X-ray diffraction techniques study the orientation of anisometric kaolin pigment particles in pap... more X-ray diffraction techniques study the orientation of anisometric kaolin pigment particles in paper coatings. Relationships between coating color solids, application geometry, and machine speed determine the degree of pigment particle alignment resulting from the dynamic separation mechanisms of the application method. Controlling blade configuration and coating color properties can optimize structural alignment in the coating layer. Roll coatings at high pigments solids concentrations develop disordered particle orientations. There is a distinct correlation between pigment particle alignment, runnability, and sheet gloss down to the microroughness limits of optical sensitivity and with offset print gloss and rotogravure printability throughout the complete orientational range. Premetering in a shear field enhances the potential orientational optimization in blade coating. Application : there is a direct correlation between the dried microstructure of a coating and the dynamic appli...
Enhancement of image quality and reduction in print-through can be achieved by printing on so-cal... more Enhancement of image quality and reduction in print-through can be achieved by printing on so-called Value Added Coldset (VAC) papers. Independent absorption tests, model coatings, commercial ink and paper samples, together with commercial printing trials, are used to illustrate the effect of pore structure and size distribution on the rate of absorption and the relative permeability of papers and coatings on the deposit build-up tendency. This work shows that runnability of specific ink and paper combinations is not a simple function of tack rate but rather a function of ink component penetration properties, specific for different surfaces, and its effect on ink adhesion in relation to permeability of the coating to fountain solution. This relates to the ability of the ink to be compatible with the fountain solution being used and the role of the basepaper in absorbing and retaining fountain solution. By developing a special tack measurement technique for coldset web offset (CSWO) ...
This paper discusses novel methods for observing the spreading and penetration behaviour of fluid... more This paper discusses novel methods for observing the spreading and penetration behaviour of fluids into specially prepared consolidated blocks of paper coating pigments which allows for the equilibrium absorption of measurable droplet sizes without saturation of the pigment layer. The mechanisms studied are responsible for a range of printing phenomena. Variables such as particle size distribution, pigment surface treatment with dispersing agents and the applied pressure during consolidation of the structure give the possibility to create a wide range of porous structures with differing structure-property relationships. By bringing liquids of differing polarity, surface tension and viscosity, stained and unstained, into contact with these porous blocks, either as a super source or in droplet form, the relevant phenomena of spreading, penetration and adsorption can be studied using image analysis techniques. Droplet absorption and pressureless fluid imbibition methods are contrasted ...
Tappi Journal, 1991
On examine les effets de la pâte a papier sur la structure du couchage, la couverture et la rugos... more On examine les effets de la pâte a papier sur la structure du couchage, la couverture et la rugosite de la feuille revetue a l'aide de techniques optiques de formation d'image. On compare les resultats obtenus avec des feuilles de pâte mecanique, de pâte thermomecanique et de pâte mecanique sous pression.
Wochenblatt Fur Papierfabrikation, 1991
On etudie les effets des variations de la geometrie de l'ecoulement dans la region proche de ... more On etudie les effets des variations de la geometrie de l'ecoulement dans la region proche de la lame en amont. On montre que l'on peut controler l'orientation de particules anisometriques, telles que celles de kaolin, en optimisant la geometrie de la lame et/ou la teneur en solides du couchage. On presente des exemples d'utilisation de ces effets pour le developpement de la structure de couchage la plus appropriee pour une application particuliere
Liquid–solid interactions are important for numerous natural and industrial processes in agricult... more Liquid–solid interactions are important for numerous natural and industrial processes in agriculture, coating, filtration, painting and printing. Understanding the effects of sequential absorption of oil components and water, in various arrangements, on porous coatings during the very short time it takes for a paper to pass through a printing machine is a prerequisite for a successful printing operation. Phenomena in the printing nip occur under far from equilibrium conditions, and therefore the interactions of liquids with the coating should also be studied in nonequilibrium conditions. When a droplet of liquid is placed on a surface its spreading is controlled by the balance of driving and resisting forces. The driving force for initial impact spreading is kinetic energy of the droplet, whereas flow resistance is provided by viscosity and surface tension of the liquid. As the kinetic energy of the impact dissipates, the wetting forces become important. Spreading of a liquid on a s...
The colorants, Fat Red Bluish (FRB) and Fat Blue B01 (FB), were investigated as potential image e... more The colorants, Fat Red Bluish (FRB) and Fat Blue B01 (FB), were investigated as potential image enhancers for paper cross sectioning by premixing directly into the embedding resin. One-side triple coated board samples were embedded using three commonly employed epoxy resins using this technique. Sections taken from the embedment were mounted respectively using immersion oil, Euparal®, and Glycerol 87 % solution. Under the light microscope excellent differentiated images with overall coloration of the whole cross-section were achieved. The degree of resin penetration could be clearly identified and the quality of cross-sections improved in respect to contrast and image definition. In this way, colorants can be used to improve well-established embedding techniques, such as the choice of resin, developing a higher quality of microscopic image, a reduction of preparation time for cross-sections etc. It may also be applied to improve or even define the contrast of cross-sections of commo...
On a developpe un modele mathematique qui decrit les effets dynamiques du couchage par lame sur l... more On a developpe un modele mathematique qui decrit les effets dynamiques du couchage par lame sur la sauce de couchage et la feuille support. On montre que l'application de poids de couche eleves permet de reduire la pression de la lame et l'angle en amont. Le brillant maximal est obtenu pour de plus faibles teneurs en solides. La reciproque est vraie lorsqu'on utilise de plus faibles poids de couche
Molecular Crystals and Liquid Crystals, 1981
The crystal and molecular structure of N-(4-n octyloxybenzylidene)-4'-butylaniline (80.4), C... more The crystal and molecular structure of N-(4-n octyloxybenzylidene)-4'-butylaniline (80.4), C25H35NO, has been determined at room temperature partially by direct methods and completed by subsequent Fourier synthesis. The crystals belong to the triclinic system with space group P1, a=5.452(3), b=7.948(4), c=27.356(4) Å, α=90.83(2), β=86.43(2) and γ=108.14(2)[ddot] with two molecules per unit cell. The structure consists of interdigitated sheets of molecules with alternate sheets in an head-to-tail configuration and displaced in the direction of the long molecular axes so as to give interdigitation of alkyl tails and of cores plus alkoxy tails. It is shown that the superficially very different structure of the homologue 40.8 may be described in a similar way. In neither case is there a close relation with the structure of the liquid crystal phase found in melting.
Molecular Crystals and Liquid Crystals, 1983
Detailed X-ray diffraction studies of bis-(4'-n-heptyloxybenzylidene)-1,4-phenylenediamine (... more Detailed X-ray diffraction studies of bis-(4'-n-heptyloxybenzylidene)-1,4-phenylenediamine (HEPTOBPD) have led to a positive phase identification, subsequently given confirmation by texture and miscibility studies. No new smectic liquid crystal phases, but two disordered crystal phases (J and K) are found which are analogous to G and H phases except for the direction of tilt.
Molecular Crystals and Liquid Crystals, 1981
Abstract The question of which of the known smetic phases exhibitis long range 3 dimensional orde... more Abstract The question of which of the known smetic phases exhibitis long range 3 dimensional order is first discussed briefly, The major theme of the paper is the nature of the structure and correlations in SB, SF, and S1 phases. Results are presented about the ...
Chemischer Informationsdienst, 1983