JP2007213031A - Developer for electronic printing and process for producing glass plate having electric conductor pattern - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for producing a glass plate having an electric wire excellent in adhesion to the surface of the glass plate, whereby it is not required to have a screen ready for every model and adjustment to desired electric heating performance and antenna performance is easy, and a developer therefor. <P>SOLUTION: The developer for electronic printing is characterized in that the ratio of F<SB>tc</SB>/F<SB>tp</SB>is at least 2.5, where F<SB>tc</SB>is the adhesive force acting between one toner particle containing conductive fine particles and one carrier, and F<SB>tp</SB>is the adhesive force acting between one toner particle containing conductive fine particles and a photoconductor. A process for forming an electric conductor pattern on a surface of a glass plate is provided which comprises forming a pattern of the toner on the surface of the glass plate by an electronic printing system using the developer for electronic printing, and heating the glass plate to a predetermined temperature to convert the pattern of the toner by firing to a pattern of an electric conductor. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a developer for electronic printing and a method for producing a glass plate having a conductor pattern, and in particular, fog is applied to a pattern of a conductor excellent in adhesion to a glass plate surface used for a window of an automobile or the like. The present invention relates to a developer for electronic printing and a method for producing a glass plate with a conductor pattern, which can be formed in a small amount and with high quality.

In recent years, various kinds of conductive wiring patterns for forming conductive wiring patterns by printing and firing toner (ink) containing conductive fine particles made of metal such as silver and thermoplastic resin on an inorganic substrate by an electronic printing method. A method has been proposed. However, since the toner for electronic printing contains more conductive fine particles than the normal printing toner, the specific gravity is large (3.0 g / cm ³ or more) and the charge amount is difficult to control. In addition, there is a problem that image quality defects (hereinafter also referred to as “fogging”) due to toner scattering are likely to occur. In particular, when fog is generated on a glass plate used for an automobile window, the fog is noticeably observed when the window is viewed through, and therefore, there is an urgent need to solve the fog.

  In order to solve this fogging, a proposal has been made to reduce the apparent specific gravity of the toner by using a conductive metal or metal oxide having a hollow or a plurality of minute holes (Patent Document 1). However, fog is greatly affected by the adhesion between the toners and between the members, and the fundamental solution is often not achieved only by controlling the weight and toner shape such as specific gravity. On the other hand, in general, there is a strong tendency to reduce the toner particle size for the purpose of improving the resolution, but there is a problem that it becomes difficult to control the toner with an electric field as the particle size is reduced. In particular, in the toner for electronic printing containing a large amount of conductive particles, it is difficult to control the charge amount due to dispersion of the particles, and it is very difficult to solve the fog by reducing the toner particle size.

  In the two-component development method, the electrostatic force between the toner and the carrier or the development electric field prevents fogging. However, in the toner containing a large amount of conductive particles, there is a toner that is not charged inside (hereinafter referred to as an uncharged toner). To do. Since the uncharged toner is not affected by the electrostatic force between the carrier and the developing electric field, there is a problem that the uncharged toner remains on the image carrier as fog.

JP 2001-281920 A (Claims)

  The present invention relates to a developer for electronic printing capable of forming a high-quality conductor pattern with excellent conductivity and less fog, and production of a glass plate with a conductor pattern obtained by using this developer. It aims to provide a method.

  The present invention provides a method for producing a glass plate having the developer for electronic printing described in the following (1) to (4) and the conductor pattern described in the following (5) to (7).

(1) Adhesive force F _tp acting between one toner particle containing conductive fine particles and a photoreceptor, and an adhesive force F _tc acting between one toner particle containing conductive fine particles and one carrier The developer for electronic printing, wherein the ratio F _tc / F _tp is 2.5 or more.
(2) The developer for electronic printing according to (1), wherein the F _tp is 40 nN or less.
(3) The adhesion force F _tt acting between one toner particle containing conductive fine particles and another toner particle containing conductive fine particles is 30 nN or less, according to (1) or (2) Developer for electronic printing.
(4) The developer for electronic printing according to any one of (1) to (3), wherein the toner particles have an average particle size of 10 to 35 μm.

(5) using the toner in the developer for electronic printing according to any one of (1) to (4), forming a pattern of the toner on a glass plate surface by an electronic printing method; and Heating the glass plate on which the pattern is formed to a predetermined temperature to convert the toner pattern into a conductor pattern, and a method for producing a glass plate having a conductor pattern.
(6) The manufacturing method of the glass plate which has a conductor pattern as described in (5) whose temperature which heats the said glass plate is 600-740 degreeC.
(7) The glass plate having the conductor pattern according to (5) or (6), wherein the glass plate is heated to convert the toner pattern into a conductor pattern, and the heated glass plate is thermally processed. Manufacturing method.

  According to the present invention, a high-quality conductive pattern with less fog can be formed on the glass plate surface with good adhesion. Therefore, a conductor pattern having desired heat generation performance and antenna performance can be easily formed on the glass plate surface.

  In the present invention, electronic printing refers to xerographic printing. In the xerographic method, a photosensitive drum having an electrostatic charge is exposed to form an electrostatic latent image, and the latent image is developed with toner to form a toner pattern on the surface of the photosensitive drum. Basically, the image is transferred from the surface of the photosensitive drum to the surface of the substrate (in the case of the present invention, the surface of a glass plate, etc.) The present invention is an invention of a developer suitable for this electronic printing. In the present specification, the developer refers to a mixture of carrier and toner.

  When the toner contained in the developer of the present invention is printed on the substrate and then heated to a predetermined temperature, the binder component in the toner starts to decompose or melt. Furthermore, it is considered that by increasing the temperature, the conductive fine particles are sintered and bonded to each other, and the binder component fills the gap between the sintered conductive fine particles. Thereafter, when the binder component is solidified by cooling, it is considered that a conductor composed of the combined conductive fine particles and the binder component filling the particle gap is generated. Therefore, the pattern formed by the toner in the developer of the present invention is heated to the predetermined temperature and then cooled to be converted into a conductor pattern. Hereinafter, heating to a temperature at which the binder component melts is also referred to as firing, and this temperature is also referred to as firing temperature. The present invention is an invention of a developer suitable for use in which a toner pattern formed by electronic printing is converted into a conductor pattern by firing.

  The substrate on which the conductor pattern is formed on the surface using the developer of the present invention may be a substrate made of a material that can withstand the predetermined temperature. As a board | substrate in this invention, a glass plate is preferable and especially the glass plate used for the window of a motor vehicle is preferable. The present invention is also a method for producing a glass plate having a conductor pattern, which comprises forming a conductor pattern on the surface of the glass plate using the developer.

  The conductor pattern in the present invention may be a pattern made of a linear conductor, a pattern made of a strip-like conductor, or a pattern in which a linear conductor and a strip-like conductor are combined. May be. For example, as shown in FIG. 3, the defogger and the antenna are usually configured with a pattern made of a linear conductor, and the bus bar is configured with a pattern made of a strip-shaped conductor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side conceptual view showing an example of a series of steps for producing a glass plate having a conductor pattern of the present invention. The glass plate G is conveyed to a printing process through steps (ST1) such as cutting, chamfering, and washing into a predetermined shape. In the printing step ST2, the toner contained in the developer is printed in a predetermined pattern on the surface of the glass plate G by the electronic printing apparatus 10. The glass plate G on which toner is printed in a predetermined pattern is conveyed into the heating furnace 30. When the glass plate G is heated to a predetermined temperature in the heating furnace 30, the toner is baked on the surface of the glass plate G to be converted into a conductor, and a glass plate having a predetermined conductor pattern is manufactured. The formed conductor pattern is conveyed to an inspection process (ST4; not shown), and the resistance value is inspected. The inspection result in the inspection step ST4 is transmitted to the computer C, and after determining whether the desired electric heating performance or antenna performance is obtained, the determination information is converted into adjustment information such as the pattern shape and line width, and printed. This is used for printing pattern control in step ST2.

  In the step ST1, a rectangular glass plate is cut into a predetermined shape, and the cut surface is chamfered. Thereafter, the glass plate is washed, preheated as necessary, and conveyed to the printing process ST2 by the conveying roll 20.

  In the printing process ST2, after the photosensitive drum 13 is neutralized by the static eliminator 14 while rotating the photosensitive drum 13, the photosensitive drum 13 is charged by the charger 12, and exposed to exposure light from the light source 15 to be exposed in a predetermined pattern. The drum 13 is exposed. Next, the exposure surface of the photosensitive drum 13 is rotated to the developing machine 11, and a toner layer having a predetermined pattern is formed on the surface of the photosensitive drum 13 by supplying toner to the photosensitive drum 13. At this time, the toner is agitated and mixed with the carrier in the developing device 11, and then conveyed through the carrier and is given to the photosensitive drum 13. The toner layer having a predetermined pattern on the surface of the photosensitive drum 13 is transferred to the surface of the glass plate G that has been conveyed along with the rotation of the photosensitive drum 13. Thus, a toner layer having a predetermined pattern is formed on the glass plate G surface. At this time, a secondary transfer plate such as an intermediate transfer belt may be interposed between the photosensitive drum 13 and the glass plate G surface. When this intermediate transfer belt is interposed, the transfer may be performed by a thermal transfer roll (not shown) that is arranged to support the intermediate transfer belt from the inside and press the glass plate G.

  The computer C stores pattern information for exposing with a predetermined pattern by irradiating exposure light. Therefore, the exposure light is emitted from the light source 15 in a predetermined pattern according to a command from the computer C. When the glass plate G is used for an automobile window, the shape of the glass plate, the shape of the conductor pattern, and the like differ depending on the model of the automobile. Therefore, by changing the command signal based on these data corresponding to the model of the automobile, it is possible to easily change from the production of one type of glass plate to the production of another type of glass plate.

  The glass plate G having a toner layer of a predetermined pattern is conveyed into the heating furnace 30 and heated to a predetermined temperature, usually about 600 to 740 ° C. Thus, the toner is baked on the glass plate G, and a conductor having a predetermined pattern is formed on the glass plate. Since glass plates for automobile windows are usually curved, when a glass plate with a conductor pattern manufactured as described above is used for an automobile window, it is heated in the firing step ST3 and tempered through bending. Is done. In some cases, not the tempering treatment but the slow cooling treatment is performed (bending of a glass plate for laminated glass). In addition, the temperature when heat-processing a glass plate is hereafter called heat processing temperature.

  The lower limit of the firing temperature is the lowest temperature at which decomposition or melting of the binder component occurs (preferably further sintering of the conductive fine particles occurs), and the upper limit of the firing temperature is usually the temperature at which the conductive fine particles melt or the binder component is completely It is the lower temperature of the temperature that disappears. Since the heat processing temperature is usually a temperature equal to or higher than the lower limit of the baking temperature, the toner is baked in the heating process by heating the glass plate to the heat processing temperature.

  When the toner is baked, a composition of conductive fine particles and a decomposed or melted binder component is formed. Furthermore, it is preferable that the conductive fine particles are in a sintered state (the fine particles are bonded together while maintaining the fine particle shape). In this case, the decomposed or melted binder component is considered to fill the gaps between the sintered conductive fine particles. It is also conceivable that the conductive fine particles form a conductor without sintering. In this case, the conductive fine particles are kept in contact with each other, and the gap between the conductive fine particles is filled with a binder component that is electrically conductive. It is considered that the fine particles are bound to each other. Thereafter, when the glass plate is cooled, the melted binder component is solidified to obtain a conductor composed of the conductive fine particles and the solidified binder component.

In the developer for electronic printing of the present invention (hereinafter referred to as the present developer), an adhesion force F _tp acting between one toner particle containing conductive fine particles and a photosensitive member (corresponding to the photosensitive drum 13); The ratio F _tc / F _tp of the adhesion force F _tc acting between one toner particle containing conductive fine particles and one carrier is 2.5 or more. When F _tc / F _tp is 2.5 or more, even if the toner particles scattered from the toner non-image area after being supplied from the developing device 11 fall on the photosensitive drum 13, they are collected on the carrier. Therefore, the occurrence of printing defects such as fogging can be suppressed. More preferably, F _tc / F _{tp is set} to 3.0 or more.

In the present specification, the adhesive force refers to a non-electrostatic adhesive force. This non-electrostatic adhesion force corresponds to the sum of van der Waals force and liquid crosslinking force. The adhesion force can be adjusted as appropriate by mainly selecting materials constituting the developer as shown below. Further, it is possible to reduce F _tp by providing fine irregularities on the surface of the photosensitive drum 13.

Next, in this developer, F _tp is preferably 40 nN or less. When F _tp is 40 nN or less, it is possible to prevent toner particles from remaining on the photosensitive drum 13 after transfer, and to prevent background contamination of the photosensitive drum 13, thereby further suppressing fogging. More preferably, F _tp is 35 nN or less.

Further, in this developer, it is preferable that the adhesion force F _tt acting between one toner particle containing conductive fine particles and another toner particle containing conductive fine particles is 30 nN or less. When F _tt is 30 nN or less, the dispersibility of the toner particles in the developer is improved and the frictional charging is also quickly performed, so that the generation of fog is further easily suppressed. More preferably, Ftt is set to 27 nN or less.

In this developer, the material of the carrier is not particularly limited, and a ferrite carrier coated with a silicone resin or an acrylic resin is preferably used. In particular, if a carrier coated with a resin having a high affinity with the resin in the toner particles is used, the van der Waals force acting between one toner particle and one carrier is increased, and F _tc can be increased. Therefore, it is preferable. The particle size of the carrier is not particularly limited, but is preferably 20 to 120 μm. When the carrier particle size exceeds 120 μm, the development becomes rough. On the contrary, when the thickness is less than 20 μm, the fog is remarkable. The van der Waals force is more preferable as the particle size is larger because the van der Waals force and F _tc acting between the toner particles can be increased by setting the carrier particle size to 20 μm or more. Further, the mixing ratio (hereinafter also referred to as T / C ratio) of the carrier (C) and the toner (T) in the developer is preferably 2 to 15% by weight. By setting the T / C ratio to 2% by weight or more, it is difficult for image fading to occur. On the other hand, by setting the T / C ratio to 15% by weight or less, frictional charging between the carrier and the toner is sufficiently performed, so that the toner particles with poor charging can be reduced. More preferably, the T / C ratio is in the range of 3 to 8% by weight.

  The toner (hereinafter also referred to as the present toner) particles in the developer preferably include conductive fine particles, a thermally decomposable binder resin (hereinafter referred to as the present binder resin), and glass frit. In this case, the thermally decomposable binder resin functions as a binder that combines the conductive fine particles and the glass frit as a single mother particle, and also transfers the toner pattern on the photosensitive drum or the like to the substrate, and the glass frit melts. It is a component that functions as a binder for fixing the conductive fine particles and the glass frit to the substrate before the process.

  After the pattern of the toner is formed on the glass plate, the binder resin in the toner is first decomposed in the heating process. The decomposed binder resin volatilizes and disappears from the glass plate by heating. After most of the binder resin is volatilized, the glass frit starts to melt and the conductive fine particles in the toner are fixed on the glass plate surface mainly by the adhesiveness of the glass frit. In these processes, by completely decomposing and volatilizing the binder resin until the glass frit is completely melted, the amount of residual resin in the conductor after firing can be reduced. Finally, when the glass plate is heated to a temperature exceeding 600 ° C., the conductive fine particles are sintered to form a conductor.

The lower limit of the firing temperature is approximately equal to or higher than the melting temperature Ts of the glass frit, and T _{100 of the} binder resin (substantially the disappearance temperature of the binder resin) is approximately equal to or lower than Ts. Preferably it is temperature. If based on this Ts, there is a possibility that T ₁₀₀ of the binder resin is decomposed product of the binder resin in too high conductor than Ts remains. Further, a possibility that T ₁₀₀ of the binder resin is too too low than the Ts, the binder resin before the glass frit is melted completely decomposed, it can not be a conductor on the glass plate surface is sufficiently secured There is. Therefore, it is preferable to select a resin having an appropriate T ₁₀₀ according Ts of the glass frit as the binder resin.

Further, the binder resin _is preferably is _{0.1~15 ℃ (T 100 -T 90)} . Since (T ₁₀₀ -T ₉₀ ) is 0.1 ° C. or higher, a small amount of the binder resin remains even when the glass frit starts to melt, so that the conductor is made of resin and glass frit in the vicinity of Ts. Both adhesiveness can fix to a glass plate surface, and can improve the adhesiveness of a glass plate surface and a conductor. On the other hand, when (T ₁₀₀ -T ₉₀ ) is 15 ° C. or less, the binder resin can be sufficiently decomposed until the glass frit is completely melted. It becomes difficult to remain, and it is hard to produce the sintering defect of electroconductive fine particles. In particular, (T ₁₀₀ -T ₉₀ ) is preferably 5 to 15 ° C.

The T ₁₀₀ indicates a temperature at which the weight change disappears when the temperature is increased from room temperature at a temperature increase rate of 10 ° C./min using a thermogravimetric analyzer (TG). The T ₉₀ is a value obtained when the decrease in the binder resin is 90% by weight when the temperature is increased from room temperature at a temperature increase rate of 10 ° C./min using a thermogravimetric analyzer (TG). Indicates temperature.

  Examples of the conductive fine particles include metal fine particles and conductive oxide fine particles. As the metal fine particles, fine particles of gold, platinum, silver or copper are preferable. The conductive oxide fine particles are preferably ITO (indium doped tin oxide) or ATO (antimony doped tin oxide) fine particles. When a glass plate on which a linear conductor pattern is formed is used for an automobile window, the line width of the linear conductor is made too large because it is necessary to prevent the provided linear conductor pattern from obstructing the field of view. It is not possible. Therefore, in order to obtain a desired resistance value with a narrow line width, it is particularly preferable to select silver fine particles as the conductive fine particles.

  The content of the conductive fine particles is preferably 59.8 to 83.8 parts by mass with respect to 100 parts by mass of the total solid content of the toner particles. Since the content of the conductive fine particles is 59.8 parts by mass or more, the conductivity of the conductor can be sufficiently maintained, and volume contraction at the time of firing of the conductor formed by firing can be suppressed. Separation from the plate surface and generation of cracks can be prevented. Further, when the amount is 83.8 parts by mass or less, a stable charge amount as a toner can be expressed. In addition, the exposed area of the conductive fine particles occupying the surface of the toner particles can be reduced, and the liquid crosslinking force acting between one toner particle and one carrier can be reduced. As a result, Ftp can be reduced. The content of the conductive fine particles is particularly preferably 69.8 to 80.8 parts by mass.

  The average particle diameter of the conductive fine particles is preferably 0.2 to 20 μm. When the average particle size is 0.2 μm or more, volume shrinkage of the obtained conductor is suppressed, and peeling from the glass plate surface can be prevented. On the other hand, when the average particle size is 20 μm or less, the print quality of the obtained conductive printed line can be improved. The average particle size of the conductive fine particles is particularly preferably from 0.5 to 10 μm. In the present specification, the average particle diameter of particles refers to the average diameter based on the number of particles. An average particle diameter can be measured by a well-known method, for example, can be measured using particle size distribution analyzers, such as a flow type, a laser diffraction and scattering type, and a dynamic light scattering type. Among these, a flow-type particle size distribution meter is particularly preferable because it can accurately measure the distribution of infrequent particles and can also measure the particle shape at the same time as the average particle size.

Any glass frit can be used regardless of whether it is lead-based or lead-free, but lead-free bismuth-silica glass frit is preferable from the viewpoint of the environment. The melting temperature Ts of the glass frit is preferably 400 to 550 ° C, and particularly preferably 450 to 500 ° C. By melting temperature Ts of the glass frit is 400 to 550 ° C., it becomes easy to select a binder resin having a _{T 100} of the relationship between the _{T 100} of the Ts and the binder resin are met, in particular 450 to 550 ° C. By doing so, it becomes easy to employ a binder resin having good decomposition characteristics. If the Ts of the glass frit exceeds 550 ° C., it is too close to the lower limit 600 ° C. of the normal processing temperature of the glass plate, and the glass frit may not be sufficiently melted when the glass plate is thermally processed.

  The binder resin is a thermally decomposable resin having the above functions, and the type of the resin is not limited as long as it has an appropriate thermal decomposition temperature and a function as a binder. However, toner aggregation or the like hardly occurs until it is supplied to the photosensitive drum, the toner adheres to the photosensitive drum with an appropriate adhesion force (Ftp), and the toner pattern on the photosensitive drum is satisfactorily transferred to the substrate. The binder resin is preferably a thermally decomposable resin having a functional group in order to exhibit functions such as good fixability of the toner pattern transferred onto the substrate. Furthermore, the functional group is preferably an acidic group such as a carboxy group.

  The binder resin is preferably a thermally decomposable resin mainly composed of an acid-modified thermoplastic resin having an acid value of 5 or more because it has good fixability to the glass plate surface and good decomposability during heat treatment. . Here, the acid value refers to the number of mg of potassium hydroxide required to neutralize acidic groups present in 1 g of resin. Although the reason why the fixability is improved by adopting a heat-decomposable resin mainly composed of an acid-modified thermoplastic resin having an acid value of 5 or more has not been elucidated, the acidic group in the binder resin is not present on the surface of the glass plate. It is thought to interact with the silanol group. Here, the binder resin may be composed of an acid-modified thermoplastic resin alone, or from a combination of an acid-modified thermoplastic resin and another thermally decomposable resin (for example, a thermoplastic resin having no acidic group). It may be. In the latter case, the proportion of the thermally decomposable resin other than the acid-modified thermoplastic resin is preferably a relatively small amount relative to the acid-modified thermoplastic resin, and the proportion is 30 with respect to the total resin amount of the binder resin. It is preferably not more than 10% by weight, particularly not more than 10% by weight. The polymer of the main chain of the acid-modified thermoplastic resin and the polymer of the main chain of another thermally decomposable resin are preferably polymers obtained by vinyl polymerization. Both main chain skeletons may be the same or different. Even when other thermally decomposable resins are contained, the acid value of this binder resin is 5 or more, and the acid value of all resins including other thermally decomposable resins having no acidic group is 5 or more. Preferably there is. Moreover, a commercially available thing can be used as an acid-modified thermoplastic resin and other thermally decomposable resin in this binder resin.

  The acid value of the binder resin is preferably 5 to 100. The acid value of the present binder resin is more preferably 20-100. As a result, when the present toner is electronically printed on the glass plate surface, a pattern with better fixability can be formed. When the acid value is 5 or more, particularly 20 or more, the number of acidic groups can be ensured, so that the fixability of the pattern is stabilized, and poor adhesion of the conductor hardly occurs after firing. On the other hand, when the acid value is 100 or less, the melt viscosity of the binder resin does not become excessively high, and the toner can be sufficiently fixed on the substrate surface when electronic printing is performed. Is less likely to occur. The acid value is more preferably 30 to 70.

  The acid-modified thermoplastic resin is a polymer having an acidic group, and the acidic group in the present invention refers to a carboxy group and a carboxylic anhydride group. The acid-modified thermoplastic resin is a thermoplastic resin having either or both of a carboxy group and a carboxylic anhydride group. The acid-modified thermoplastic resin is preferably a polymer obtained by copolymerizing a monomer having an acidic group or a polymer obtained by reacting a compound having an acidic group with a thermoplastic resin. Moreover, an acidic group containing polymer can also be obtained by hydrolyzing a polymer obtained by copolymerizing an unsaturated carboxylic acid ester monomer. The acid-modified thermoplastic resin in the present invention is particularly preferably an acid-modified thermoplastic resin obtained by reacting a pre-manufactured thermoplastic resin with a compound having an acidic group.

  The main monomers constituting the acid-modified thermoplastic resin include aromatic vinyl monomers such as olefins and styrene, (meth) acrylate monomers such as acrylic esters and methacrylic esters, and unsaturated alcohol ester monomers such as vinyl acetate. And diene monomers such as butadiene. In particular, a thermoplastic resin obtained using an olefin having 6 or less carbon atoms such as ethylene or propylene as a main monomer is preferable.

  As the compound having an acidic group (hereinafter referred to as an acid modifier), an unsaturated carboxylic acid or an unsaturated polycarboxylic acid anhydride is preferable. In particular, unsaturated dicarboxylic acid and unsaturated dicarboxylic acid anhydride are preferable. Specific examples include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, and citraconic anhydride. In particular, maleic anhydride is preferred as the acid modifier. Accordingly, the acid-modified thermoplastic resin is preferably an acid-modified thermoplastic resin obtained by reacting an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride with a thermoplastic resin, and particularly preferably a maleic anhydride-modified thermoplastic resin.

  As the acid-modified thermoplastic resin, an acid-modified polyolefin obtained by reacting a polyolefin-containing compound with an acidic group is preferable. Examples of the polyolefin include polyethylene, polypropylene, and ethylene-propylene copolymer. Among them, polypropylene is preferable because it is easy to ensure a stable charge amount as a toner. As a method of reacting an acid modifier with a polyolefin, a method in which an acid modifier and a radical generator (peroxide, etc.) are mixed in the polyolefin and heated, a low molecular weight obtained by partial thermal decomposition of the polyolefin in advance. A method in which an acid modifier is mixed and reacted with polyolefin (having a reactive site such as an unsaturated group) can be employed. As the acid-modified polyolefin, maleic anhydride-modified polyolefin obtained by these methods using maleic anhydride as an acid-modifying agent, particularly maleic anhydride-modified polypropylene, has a large charge amount, a rapid charge rise, and stable charge. From the viewpoint of sex. The weight average molecular weight of the acid-modified polyolefin is not particularly limited, but is preferably 3000 to 150,000, and particularly preferably 5000 to 80,000.

As for the thermal decomposability of the binder resin, it is preferable to have an appropriate T ₁₀₀ according to the melting temperature Ts of the glass frit as described above. Therefore, it is preferable to select a thermally decomposable resin having an appropriate T ₁₀₀ according to the value of Ts of the glass frit used. The difference (Ts−T ₁₀₀ ) between the melting temperature Ts of the glass frit and the T _{100 of the} binder resin is preferably 0 to 20 ° C. When (Ts−T ₁₀₀ ) is 0 to 20 ° C., melting of the glass frit can be started before the binder resin is decomposed and completely volatilized, and adhesion between the glass plate surface and the conductor is improved. Can be enhanced. In addition to the above, the difference (Ts−T ₉₀ ) between Ts and T90 of the present binder resin is preferably 0 to 80 ° C. Since (Ts−T ₉₀ ) is 0 ° C. or more, a small amount of the binder resin remains even when the glass frit starts to melt, and thus the adhesive properties of both the binder resin and the glass frit in the vicinity of Ts. Thus, it is considered that the conductor can be fixed to the glass plate surface and the conductor can be sufficiently adhered to the glass plate surface. On the other hand, when (Ts−T ₉₀ ) is 80 ° C. or less, the binder resin can be sufficiently decomposed until the glass frit is completely melted, so that the binder resin remains as a carbide in the conductor. This is considered to be difficult to cause sintering failure between the conductive fine particles and to improve the adhesion of the conductor to the glass plate surface. More preferably _{(Ts-T 90)} is 0.1 to 50 ° C..

As will be described later, the melting temperature Ts of the glass frit is preferably 450 to 500 ° C. In that case, _{T 100} of the binder resin is preferably 420-450 ° C.. In this case, by T ₁₀₀ is 420 ° C. or higher, before the glass frit is melted, the binder resin can be prevented from being completely decomposed, that conductor on the glass plate surface is sufficiently secured it can. On the other hand, when T ₁₀₀ is 450 ° C. or lower, when the toner is baked, the binder resin is rapidly decomposed and volatilized, so that there is almost no residual carbon remaining in the conductor. In addition to being able to obtain a conductor excellent in conductivity without interfering with each other, it is possible to obtain a conductor excellent in adhesion to the glass plate surface.

The content of the binder resin is preferably 5 to 40 parts by mass with respect to 100 parts by mass of the total solid content of the toner particles. When the content is 5 parts by mass or more, when the toner is electronically printed, the fixing property with the substrate can be sufficiently secured. Further, the exposed area of the conductive fine particles occupying the surface of the toner particles can be reduced, and the liquid crosslinking force acting between one toner particle and one carrier can be reduced. As a result, F _tp can be reduced. When the content is 40 parts by mass or less, the binder resin is less likely to remain in the fired conductor, so that defects such as cracks and voids are less likely to occur in the conductor. The content of the binder resin is particularly preferably 10 to 30 parts by mass.

  The content of the glass frit is preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the total solid content of the toner particles. When the content of the glass frit is 0.2 parts by mass or more, the adhesion of the conductor to the substrate surface can be sufficiently ensured. On the other hand, when the content is 5 parts by mass or less, the glass against the conductive fine particles is obtained. An increase in the specific resistance of the conductor pattern due to an increase in the amount of the frit component can be suppressed. The glass frit is preferably a powder having an average particle size of 0.1 to 5 μm. When the glass frit has an average particle size of 0.1 μm or more, sufficient adhesion to the substrate surface can be secured, and when the average particle size is 5 μm or less, the glass frit is exposed on the surface of the toner particles. This can be prevented, and the fixability is hardly lowered when printed on the surface of the substrate by the electronic printing method. The glass frit particularly preferably has an average particle size of 0.5 to 3 μm.

  In addition to the above components, the toner particles in the developer may include, as appropriate, inorganic pigments such as black iron oxide, cobalt blue, and red bean paste, azo-based metal-containing dyes, salicylic acid-based metal-containing dyes, quaternary grades. A charge control agent such as an ammonium salt can be contained.

  The toner is manufactured by, for example, mixing the binder resin, conductive fine particles, glass frit, and the like, kneading and cooling to produce pellets, and then pulverizing and classifying. At this time, it is preferable that heating temperature is 150-200 degreeC. By setting the heating temperature to 150 ° C. or higher, the present binder resin, conductive fine particles, glass frit and the like can be mixed uniformly. On the other hand, decomposition of this binder resin can be prevented because heating temperature is 200 degrees C or less.

In this developer, the average particle size of the toner particles is preferably 10 to 35 μm. When the average particle size is 10 μm or more, the conductive fine particles in the toner can be prevented from being exposed on the surface, and the charge amount of the toner can be secured, so that the charge amount of the toner is insufficient during electronic printing. Occurrence of printing defects such as fogging can be suppressed. On the other hand, when the average particle size is 35 μm or less, high-definition print quality is easily obtained. In particular, it is preferable to set the average particle diameter of the toner particles to 15 μm or more because van der Waals force acting between one toner particle and one carrier is increased, and F _tc can be increased.

If the shape of the toner particles is spherical, the contact area between the toner particles can be reduced, and the van der Waals force acting between the toner particles can be reduced. As a result, a developer having a small F _tt is easily obtained. .

  Further, fine particles (hereinafter also referred to as external additives) may be dispersed and adhered to the surfaces of the toner particles. Dispersing and adhering the external additive to the surface of the toner particles has a function of improving the fluidity of the toner in the developing machine 11 without impairing the transfer rate from the photosensitive drum 13 or the like to the glass plate surface. In addition, the exposed area of the conductive fine particles occupying the surface of the toner particles can be reduced, and the liquid crosslinking force acting between one toner particle and one carrier can be reduced. As a result, Ftp can be reduced. The type of the external additive is not particularly limited, and inorganic fine particles made of silica, titanium oxide or the like, and thermally decomposable organic resin fine particles are preferably used. Among these, it is preferable to use thermally decomposable organic resin fine particles as an external additive because the charge amount distribution of the toner can be controlled. As such an organic resin, it is preferable to use a thermoplastic resin that decomposes and volatilizes quickly by heating. For example, at least one selected from the group consisting of polyethylene, polypropylene, polystyrene, acrylic resin, and styrene-acrylate copolymer resin is used. Can be mentioned. In particular, an acrylic resin and / or a styrene-acrylate copolymer-based resin is preferable in that the charging characteristics of the toner can be improved.

  The particle size of the external additive is preferably 10 to 800 nm. By setting the particle size to 10 nm or more, it is easy to obtain the effect of improving the fluidity of the toner and improving the transfer rate and image quality. On the other hand, by setting the particle size to 800 nm or less, the toner can be uniformly dispersed on the surface of the toner particles as an external additive, and the fluidity of the toner can be improved. At this time, if the ratio of the particle size of the external additive to the particle size of the present toner particles is in the range of [particle size of external additive] / [particle size of the present toner particle] = 0.003 to 0.05. In particular, the effect of improving the fluidity of the toner is easily obtained, which is particularly preferable. Further, it is preferable that the shape of the external additive is spherical, since the external additive is uniformly dispersed on the surface of the toner particles and the effect of improving the fluidity of the toner is easily obtained.

  The content of the external additive is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the toner particles. When the content is 0.1 part by mass or more, the fluidity of the toner is improved, and the effect of improving the transfer rate and the image quality is easily obtained. On the other hand, when the content of the external additive is 5 parts by mass or less, it is possible to prevent the fixing property between the toner particles and the glass plate surface from being hindered. The content of the external additive is particularly preferably 1 to 3 parts by mass with respect to 100 parts by mass of the present toner particles. The external additive can be attached to the toner particles by using a particle compounding device represented by a hybridization system (manufactured by Nara Machinery Co., Ltd.), a mixer such as a Henschel mixer or a pass mixer.

  By using the toner in the developer obtained above and forming a pattern of the toner on the substrate surface by an electronic printing method, the conductor can be formed by baking. When the substrate is a glass plate, the firing temperature is preferably 600 to 740 ° C. When the firing temperature is 600 ° C. or higher, the conductive fine particles are sufficiently sintered. On the other hand, when the firing temperature is 740 ° C. or lower, deformation of the glass plate can be prevented. In the present invention, soda lime glass, non-alkali glass, quartz glass and the like can be used as the glass plate.

  The conductor formed according to the present invention preferably has a specific resistance of 20 μΩ · cm or less. This is preferable because it can be used as a conductor for various purposes such as wiring. Moreover, it is preferable that the film thickness of a conductor is 5-30 micrometers. When the film thickness is 5 μm or more, a stable specific resistance can be easily obtained, and when the film thickness is 30 μm or less, a desired film thickness can be easily obtained even by one-time electronic printing, and the handling is excellent.

  FIG. 2 is a conceptual diagram illustrating a control process according to a preferred embodiment of the present invention. The toner is printed in a predetermined pattern in the printing process ST2 on the glass plate pretreated in ST1, and heated in the firing process ST3 to burn the toner to produce a glass plate with a conductor. After the firing step ST3, the resistance value of the conductor fired in the inspection step ST4 is measured. The measured resistance value data is sent to the computer C which controls the toner pattern in the printing process. If necessary, temperature data in the firing step ST3 is also sent to the computer C. The data sent to the computer C is used as data for determining whether desired electric heat performance and antenna performance can be obtained. When it is determined that the desired performance is not obtained, the line width of the toner printed or the print pattern itself is adjusted by the calculation of the computer C so as to obtain the desired performance. The adjusted toner line width and printing pattern are fed back to the printing step ST2, and a conductor is provided on the next glass plate.

  If desired electrothermal performance and antenna performance are obtained by such feedback, control data can be fixed and a glass plate with a conductor can be manufactured in large quantities.

  Further, when the glass plate G is used for an automobile window, the computer C can store and accumulate glass plate shape data, conductive printed line pattern shape data, etc. according to the type of the vehicle. This makes it easy to change from one model to another by sending a command to the electronic printer based on the data related to the pattern shape of the conductive printed wire corresponding to that model when manufacturing a glass plate for that model. The printing according to each model can be performed. Furthermore, by sending a command based on the shape data of the glass plate among the data relating to the model to the cutting and chamfering step (ST1) of the glass plate, it is possible to easily change from one type to another type according to each type. Cutting and chamfering can be performed.

  For example, the rear window of the automobile illustrated in FIG. 3 is provided with a conductive printed wire (defogger 1, antenna wire 2, bus bar 3) in the central region of the glass plate G, and a dark ceramic fired body 4 in the peripheral region. However, if the developer for electronic printing of the present invention is used, the above-mentioned conductive printed wire can be printed on the glass plate surface by a manufacturing method suitable for mass production.

Examples 1-2 (Examples) and Example 3 (Comparative Examples) are shown below. Here, in Examples 1 to 3, the decomposition temperature was between room temperature and 700 ° C. at a temperature increase rate of 10 ° C./min using a thermogravimetric analyzer (manufactured by Shimadzu Corporation, model: DTG-50). The temperature T _{100 at} which the weight change of the resin disappears and the temperature T ₉₀ when the decrease amount of the resin reached 90% were determined.

  The average particle diameter of the particles is 50 in the cumulative particle size distribution curve based on the number of equivalent circle diameters measured using a flow particle image analyzer (trade name: FPIA-3000, manufactured by Sysmex Corporation). %.

  In addition, the average molecular weight of the resin used in Examples 1 to 3 refers to the weight average molecular weight.

[Example 1]
Maleic anhydride-modified polypropylene (manufactured by Sanyo Kasei Co., Ltd., trade name: Yumex 1010, average molecular weight 30000, acid value 52, T ₁₀₀ = 430 ° C., T ₉₀ = 420 ° C.) 20 parts by mass, silver powder (average particle size 2 μm) 79 parts by mass 1 part by weight of glass frit (bismuth-silica lead-free frit: melting temperature Ts = 450 ° C., average particle size 2 μm), kneaded at 170 ° C. using a kneader, cooled to room temperature, Obtained. This solid was pulverized with a jet mill and classified to obtain toner particles having an average particle diameter of 20 μm.

  To 5 parts by mass of the toner particles obtained above, 95 parts by mass of a carrier made of iron oxide coated with an acrylic resin (manufactured by Powdertech, trade name: EF80-47, average particle size 80 μm) is mixed. A developer having a C ratio of 5.3% by mass was obtained.

  Using this developer, on a glass plate made of soda lime glass (length 30 cm, width 30 cm, thickness 3.5 mm), a thin wire having a line width of 1 mm and a length of 80 mm is obtained with an electronic printing machine (Mitsubishi Heavy Industries, Ltd.). After printing, baking was performed at 700 ° C. for 4 minutes to form conductive lines.

  The following evaluation was performed about the obtained developer and the conductive printed wire. The evaluation results are shown in Table 1. Hereinafter, evaluation was similarly performed in Examples 2 to 3.

[Adhesion evaluation]
Using an apparatus for measuring adhesion between fine particles (Okada Seiko Co., Ltd., trade name: Contactle PAF-300N), adhesion between toner / carrier (F _tc ), adhesion between toner / photoreceptor (F _tp ) And toner / toner adhesion (F _tt ).

[Fog particle evaluation]
A glass plate obtained by printing and baking was observed with an optical microscope, and a range of 3 mm × 3 mm in field of view was set as a shooting region unit, and 10 shooting regions on the glass plate surface were visually selected. After observing each selected photographing region unit and accumulating the total number of fog particles, the average value of the number of fog particles per unit area was taken as the fog particle number.

[Example 2]
With respect to 99 parts by mass of toner particles obtained in Example 1, spherical fine particles made of acrylic resin as thermally decomposable organic resin fine particles (manufactured by Soken Chemical Co., Ltd., trade name: MP-300, average particle size 100 nm, T ₁₀₀ = 370) 1 part by mass was added, and spherical particles made of acrylic resin were adhered to the toner particles using a hybridization system (manufactured by Nara Machinery Co., Ltd.) to obtain toner particles. A developer was obtained in the same manner as in Example 1 except that the toner particles were used.

[Example 3 (comparative example)]
A developer was obtained in the same manner as in Example 1 except that 15 parts by mass of maleic anhydride-modified polypropylene and 84 parts by mass of silver powder were used.

From the results of Table 1, it can be seen that in Examples (Examples 1 and 2) in which F _tc / F _tp is 2.5 or more, a glass plate having a small number of fog particles and high-quality conductive wires was obtained. .

  According to the present invention, a conductive wire with high image quality and little fog can be formed on the glass plate surface with good adhesion, and thus it is particularly suitable for manufacturing a glass plate with conductive wires (defogger wiring, antenna wiring, etc.) for automobile windows. Is available.

It is a side surface conceptual diagram which shows an example of a series of processes which manufacture the glass plate which has a conductor pattern of this invention. It is a conceptual diagram explaining the control process which concerns on the preferable form of this invention. It is a front view which shows an example of a motor vehicle rear window.

Explanation of symbols

1: Defogger 2: Antenna wire 3: Bus bar 4: Dark ceramic fired body 10: Electronic printing device 11: Developer 12: Charger 13: Photoconductive drum 14: Electrification machine 15: Light source 20: Conveying roll 30: Heating furnace G: Glass plate C: Computer ST1: Chamfering process ST2: Printing process ST3: Firing process ST4: Inspection process

Claims (7)

The ratio F _tc between the adhesion force F _tp acting between one toner particle containing conductive fine particles and the photoreceptor and the adhesion force F _tc acting between one toner particle containing conductive fine particles and one carrier. A developer for electronic printing, wherein / F _tp is 2.5 or more. The developer for electronic printing according to claim 1, wherein the F _tp is 40 nN or less. And one toner particles containing conductive particles, adhesion F _tt acting between one another toner particles containing conductive fine particles is less than 30NN, electronic printing developer according to claim 1 or 2 .   The developer for electronic printing according to claim 1, wherein the toner particles have an average particle size of 10 to 35 μm.   A step of forming the toner pattern on the glass plate surface by the electronic printing method using the toner in the developer for electronic printing according to any one of claims 1 to 4, and the toner pattern being formed And a step of heating the glass plate to a predetermined temperature to convert the toner pattern into a conductor pattern.   The manufacturing method of the glass plate which has a conductor pattern of Claim 5 whose temperature which heats the said glass plate is 600-740 degreeC.   The method for producing a glass plate having a conductor pattern according to claim 5 or 6, wherein the glass plate is heated to convert the toner pattern into a conductor pattern, and the heated glass plate is thermally processed.

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