A method for reducing color loss from hair treated with an oxidative composition, such as an oxidative hair dye, the method comprising the step of contacting the hair, either prior to or after treatment of the hair with the oxidative composition, with a color protective composition comprising an organic amino compound selected from:

This invention relates to a method of reducing colour loss from hair treated with an oxidative composition, such as an oxidative hair dye, using certain selected organic amino compounds.
The most commonly used method of dyeing hair, particularly human hair, is oxidative dyeing in which a mixture of aromatic compounds, generally of the benzenoid series, which are themselves colourless, are converted by coupling reactions to a blend of coloured compounds within the hair fibers by oxidative processes. The colourless aromatic compounds, in a suitable base formulation, are normally mixed with hydrogen peroxide or other strong oxidizing agent shortly before use. The coloured compounds or dyes are, typically, formed by oxidative coupling between primary intermediates (usually diamino benzenes or amino phenols) and couplers which are phenols or related cyclic compounds. Various shades are developed by using a mixture containing more than one of both the intermediate and the coupler.
The intermediates and couplers because of their low molecular weights and water solubility diffuse easily into the hair where the coupling reaction takes place. The coloured products developed by oxidation, however, remain trapped in the hair by virtue of their higher molecular weights, relative insolubility in water and absorptive affinity to the internal hair surface. Although permanence is the objective of such oxidative dyeing methods, in practice it is difficult to achieve. The colour tends to fade over time and a contributory factor in fading is lack of wash-fastness. This means that the colour tends to leach out of the hair after repeated washing. This leads to gradual fading or changing of the applied colour. The action of other factors such as ultraviolet light, combing and perspiration also affects the colour.
We have now found that certain selected organic amino compounds, in particular arginine and urea, are effective for reducing colour loss from hair previously or subsequently treated with an oxidising agent such as an oxidative hair dye.
U.S. Pat. No. 3,861,868 describes an oxidation dye composition comprising arginine or a protein or polypeptide having a high arginine content, and theories that the arginine or proteins enhance the penetration of the dye precursors into the hair shaft, thereby stabilizing the dye molecules formed by oxidation.
In the above case the arginine or proteins are an integral component of the dye composition itself. In contrast, the present invention provides a method in which the selected organic amino compounds are incorporated into a conventional hair treatment composition such as a shampoo or conditioner to be applied in a separate stage to the oxidative composition. Advantageously, such a shampoo or conditioner can be applied repeatedly to give a beneficial progressive build-up of the colour protection effect, independently of the oxidative composition, for which repeated use would be damaging to the hair.
The present invention provides a method for reducing colour loss from hair treated with an oxidative composition, such as an oxidative hair dye, the method comprising the step of contacting the hair, either prior to or after treatment of the hair with the oxidative composition, with a colour protective composition comprising an organic amino compound selected from:
(i) basic amino acids;
(ii) urea;
(iii) guanidine;
(iv) salts and/or derivatives of any of (i) to (iii);
(v) mixtures of any of (i) to (iv).
According to the method of the present invention, hair is contacted with a colour protective composition comprising certain selected organic amino compounds as described above, either prior to, or after treatment of the hair with an oxidative composition.
Preferably the colour protective composition is applied after treatment of the hair with the oxidative composition.
Oxidative Composition
By xe2x80x9ctreatment with an oxidative compositionxe2x80x9d is meant contacting the hair with an oxidative composition such as an oxidative hair dye.
The composition employed may be formed separately from the hair and then applied. It may also be formed by mixing the separate reactants as they are applied to the hair, for example by mixing the streams from separate aerosol containers as the streams are applied to the hair. It may also be formed by contacting the reactants with the hair to be treated as the reactants are applied to the hair, either concurrently or successively.
The term xe2x80x9coxidative dyexe2x80x9d includes compounds and mixtures of compounds which can be oxidised under the treatment conditions described above to form hair colourants. It includes, for example, primary intermediates either alone or together with one or more couplers, autoxidative dyes, and melanin forming dyes such as DHI and its analogues. Hydrogen peroxide is the usual oxidising agent employed in conjunction with oxidative dyes. Other oxidizing agents for use in this context include perborates, persulfates and perhalites, particularly periodates. These oxidising agents are generally employed as ammonium salts or as salts of alkali metals.
Colour Protective Composition
The colour protective composition comprises an organic amino compound selected from:
(i) basic amino acids;
(ii) urea;
(iii) guanidine;
(iv) salts and/or derivatives of any of (i) to (iii);
(v) mixtures of any of (i) to (iv).
Basic Amino Acids
Basic amino acids (i) may be selected from lysine, arginine and histidine and mixtures thereof. These amino acids are hydrophilic due to their polar side chains. Lysine and arginine are positively charged at neutral pH, whereas histidine can be uncharged or positively charged depending on its local environment.
Arginine is the most preferred amino acid (i) in the method according to the invention.
Alternatively, proteins, polypeptides or other natural extracts having a high basic amino acid content can be used. For example, proteins having a major proportion of arginine units (in the range from about 50 to about 90%, by weight, of the total protein) in their structures are members of that class of proteins known as protamines. The protamine proteins are characterised by having: (a) a low molecular weight, in the range of about 5,000; (b) a high isoelectric point, in the pH range of about 10 to 12; and (c) a high arginine content, in the range from about 50 to about 90%, by weight of the total protein. Suitable examples are described in U.S. Pat. No. 3,997,659.
Proteins of high basic amino acid content as described above can be subjected to acid or base hydrolysis to yield polypeptides which also have a high basic amino acid content. Examples of suitable polypeptides are also described in U.S. Pat. No. 3,997,659, being protamine-derived polypeptides having a molecular weight below about 5,000, a basic pH (10-12), and an arginine content of about 50%, or greater, by weight of the total polypeptide.
Not only may naturally occurring proteins be used, but also synthetic proteins, for example, polylysine and polyarginine, or mixtures thereof.
An example of a suitable natural extract which is rich in arginine is aloe vera extract.
The basic amino acids and the proteins and polypeptides having a basic amino acid content of 50%, or greater, are often isolated from natural sources in the form of salts and hydrosalts, which are also suitable for use according to the invention. Such salts and hydrosalts are formed by reaction with mineral acids such as hydrochloric acid, phosphoric acid, carbonic acid, sulfuric acid, nitric acid, and the like, or the organic acids such as formic acid, acetic acid, lauric acid, chloroacetic acid and the like. A suitable example is arginine hydrochloride.
Guanidine (iii) may also be present as a salts or hydrosalts formed by reaction with mineral or organic acids as described above. A suitable example is guanidine hydrochloride.
The most preferred organic amino compounds in the method according to the invention are arginine and urea and their respective salts and/or hydrosalts.
Mixtures of any of the above organic amino compounds may also be used.
The total amount of organic amino compound may suitably range from 0.01% to 10% by weight based on total weight of the hair treatment composition in which it is employed. Preferably, the amount of organic amino compound ranges from 0.02 to 5% by weight based on total weight, and will ideally range from 0.05% to 2% by weight based on total weight.
Product Form
Colour protective compositions according to the invention may suitably take the form of shampoos, conditioners, sprays, mousses, gels, cremes or lotions. Preferred forms are shampoos and conditioners.
Advantageously, the colour protective composition comprising an organic amino compound for use in the method according to the invention can be formulated as a shampoo and will then accordingly comprise one or more cleansing surfactants which are cosmetically acceptable and suitable for topical application to the hair.
Suitable cleansing surfactants, which may be used singularly or in combination, are selected from anionic, amphoteric and zwitterionic surfactants, and mixtures thereof.
Examples of anionic surfactants are the alkyl sulphates, alkyl ether sulphates, alkaryl sulphonates, alkanoyl isethionates, alkyl succinates, alkyl sulphosuccinates, N-alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates, alkyl ether carboxylates, and alpha-olefin sulphonates, especially their sodium, magnesium, ammonium and mono-, di- and triethanolamine salts. The alkyl and acyl groups generally contain from 8 to 18 carbon atoms and may be unsaturated. The alkyl ether sulphates, alkyl ether phosphates and alkyl ether carboxylates may contain from 1 to 10 ethylene oxide or propylene oxide units per molecule.
Preferred anionic surfactants include sodium oleyl succinate, ammonium lauryl sulphosuccinate, ammonium lauryl sulphate, sodium dodecylbenzene sulphonate, triethanolamine dodecylbenzene sulphonate, sodium cocoyl isethionate, sodium lauryl isethionate and sodium N-lauryl sarcosinate. The most preferred anionic surfactants are sodium lauryl sulphate, triethanolamine monolauryl phosphate, sodium lauryl ether sulphate 1 EO, 2EO and 3EO, ammonium lauryl sulphate and ammonium lauryl ether sulphate 1EO, 2EO and 3EO.
Examples of amphoteric and zwitterionic surfactants include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines(sultaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphopropionates, alkylamphoglycinates, alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates, wherein the alkyl and acyl groups have from 8 to 19 carbon atoms. Preferred amphoteric and zwitterionic surfactants include lauryl amine oxide, cocodimethyl sulphopropyl betaine and preferably lauryl betaine, cocamidopropyl betaine and sodium cocamphopropionate.
The cleansing surfactant(s) may be present in shampoo compositions for use according to the invention in a total amount of from about 1 to about 40% by weight based on the total weight of the shampoo composition, preferably from about 2 to about 30% by weight, optimally from about 10% to 30% by weight.
Shampoos for use according to the invention can also include nonionic surfactants to help impart aesthetic, physical or cleansing properties to the composition. The nonionic surfactant can be included in an amount ranging from 0% to about 5% by weight based on total weight.
For example, representative nonionic surfactants include condensation products of aliphatic (C8-C18) primary or secondary linear or branched chain alcohols or phenols with alkylene oxides, usually ethylene oxide and generally having from 6 to 30 ethylene oxide groups.
Other representative nonionics include mono- or di-alkyl alkanolamides. Examples include coco mono- or di-ethanolamide and coco mono-isopropanolamide.
Further nonionic surfactants which can be included are the alkylpolyglycosides (APGs). Typically, the APG is one which comprises an alkyl group connected (optionally via a bridging group) to a block of one or more glycosyl groups. Preferred APGs are defined by the following formula:
ROxe2x80x94(G)n
wherein R is a branched or straight chain alkyl group which may be saturated or unsaturated and G is a saccharide group.
R may suitably represent a mean alkyl chain length of from about C5 to about C20. Preferably R represents a mean alkyl chain length of from about C5 to about C12. Most preferably the value of R lies between about 9.5 and about 10.5. G may be selected from C5 or C6 monosaccharide residues, and is preferably a glucoside. G may be selected from the group comprising glucose, xylose, lactose, fructose, mannose and derivatives thereof. Preferably G is glucose.
The degree of polymerisation, n, may have a value of from about 1 to about 10 or more. Preferably, the value of n lies in the range of from about 1.1 to about 2. Most preferably the value of n lies in the range of from about 1.3 to about 1.5.
Suitable alkyl polyglycosides are commercially available and include for example those materials identified as: Oramix NS10 ex Seppic; Plantaren 1200 and Plantaren 2000 ex Henkel.
Likewise shampoos for use according to the invention can include other emulsifiers, conditioning agents, inorganic salts, humectants and similar materials to provide the composition with desirable aesthetic or physical properties.
Representative conditioning agents include silicones. Silicones are particularly preferred conditioning agents for hair. Representative silicones include volatile and non-volatile silicones, such as for example polyalkylsiloxanes (optionally end-capped with one or more hydroxyl groups), polyalkylaryl siloxanes, siloxane gums and resins, cyclomethicones, aminofunctional silicones, quaternary silicones and mixtures thereof.
Preferred silicones include polydimethylsiloxanes (of CTFA designation dimethicone), siloxane gums, aminofunctional silicones (of CTFA designation amodimethicone) and hydroxylated polydimethylsiloxanes (of CTFA designation dimethiconol).
Various methods of making emulsions of particles of silicones are available and are well known and documented in the art.
Suitable silicone emulsions are commercially available in a pre-emulsified form. This is particularly preferred since the pre-formed emulsion can be incorporated into the shampoo composition by simple mixing.
Examples of suitable pre-formed emulsions include emulsions DC2-1310, DC2-1865, DC2-1870, DC2-1766 and DC2-1784, available from Dow Corning. These are emulsions of dimethiconol. Siloxane gums are also available in a pre-emulsified form, which is advantageous for ease of formulation. A preferred example is the material available from Dow Corning as DC X2-1787, which is an emulsion of cross-linked dimethiconol gum.
The amount of silicone incorporated into compositions for use according to the invention depends on the level of conditioning desired and the material used. A preferred amount is from 0.01 to about 10% by weight of the total composition although these limits are not absolute. The lower limit is determined by the minimum level to achieve conditioning and the upper limit by the maximum level to avoid making the hair and/or skin unacceptably greasy. We have found that an amount of silicone of from 0.5 to 1.5% by weight of the total composition, is a particularly suitable level.
A further preferred class of conditioning agents are per-alk(en)yl hydrocarbon materials, used to enhance the body, volume and stylability of hair.
EP 567 326 and EP 498 119 describe suitable peralk(en)yl hydrocarbon materials for imparting stylability and enhanced body to hair. Preferred materials are polyisobutylene materials available from Presperse, Inc. under the PERMETHYL trade name.
The amount of per-alk(en)yl hydrocarbon material incorporated into compositions for use according to the invention depends on the level of body and volume enhancement desired and the specific material used. A preferred amount is from 0.01 to about 10% by weight of the total composition although these limits are not absolute. The lower limit is determined by the minimum level to achieve the body and volume enhancing effect and the upper limit by the maximum level to avoid making the hair unacceptably stiff. We have found that an amount of per-alk(en)yl hydrocarbon material of from 0.5 to 2% by weight of the total composition is a particularly suitable level.
Shampoo compositions for use according to the invention may also include a polymeric cationic conditioning compound that is substantive to the hair and imparts conditioning properties to the hair.
The polymeric cationic conditioning compound will generally be present at levels of from 0.01 to 5%, preferably from about 0.05 to 1%, more preferably from about 0.08% to about 0.5% by weight. Synthetic or naturally derived polymers having a quaternised nitrogen atom are useful. The molecular weight of the polymer will generally be between 5,000 and 10,000,000, typically at least 10,000 and preferably in the range 100,000 to about 2,000,000.
Representative synthetic quaternised polymers include, for example: cationic copolymers of 1-vinyl-2-pyrrolidine and 1-vinyl-3-methyl-imidazolium salt (e.g., Chloride salt) (referred to in the industry by the Cosmetic, Toiletry, and Fragrance Association, xe2x80x9cCTFAxe2x80x9d. as Polyquaternium-16); copolymers of 1-vinyl-2-pyrrolidine and dimethylaminoethyl methacrylate (referred to in the industry by CTFA as Polyquaternium-11); cationic diallyl quaternary ammonium-containing polymers including, for example, dimethyldiallylammonium chloride homopolymer (referred to in the industry (CTFA) as Polyquaternium 6); mineral acid salts of amino-alkyl esters of homo-and co-polymers of unsaturated carboxylic acids having from 3 to 5 carbon atoms, as described in U.S. Pat. No. 4,009,256; and cationic polyacrylamides as described in WO95/22311.
Representative naturally-derived quaternised polymers include quaternised cellulosic compounds and cationic guar gum derivatives, such as guar hydroxypropyltrimonium chloride. Examples are JAGUAR C-13S, JAGUAR C-15, and JAGUAR-C17, commercially available from Meyhall in their JAGUAR trademark series.
Compositions for use in accordance with the invention may also be formulated as a hair conditioner for the treatment of hair (typically after shampooing) and subsequent rinsing. Such formulations will then accordingly comprise one or more conditioning surfactants which are cosmetically acceptable and suitable for topical application to the hair.
Suitable conditioning surfactants are selected from cationic surfactants, used singly or in admixture. Examples include quaternary ammonium hydroxides or salts thereof, e.g chlorides.
Suitable cationic surfactants include cetyltrimethylammonium chloride, behenyltrimethylammonium chloride, cetylpyridinium chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride, didodecyldimethylammonium chloride, dioctadecyldimethylammonium chloride, tallowtrimethylammonium chloride, cocotrimethylammonium chloride, and the corresponding hydroxides thereof. Further suitable cationic surfactants include those materials having the CTFA designations Quaternium-5, Quaternium-31 and Quaternium-18. Mixtures of any of the foregoing materials may also be suitable. A particularly useful cationic surfactant for use in hair conditioners of the invention is cetyltrimethylammonium chloride, available commercially, for example as GENAMIN CTAC, ex Hoechst Celanese.
In hair conditioners for use according to the invention, the level of cationic surfactant is preferably from 0.01 to 10%, more preferably 0.05 to 5%, most preferably 0.1 to 2% by weight of the composition.
Conditioners for use according to the invention advantageously incorporate a fatty alcohol material. The combined use of fatty alcohol materials and cationic surfactants in conditioning compositions is believed to be especially advantageous, because this leads to the formation of a lamellar phase, in which the cationic surfactant is dispersed.
Representative fatty alcohols comprise from 8 to 22 carbon atoms, more preferably 16 to 20. Examples of suitable fatty alcohols include cetyl alcohol, stearyl alcohol and mixtures thereof.
The level of fatty alcohol materials is conveniently from 0.01 to 10%, preferably from 0.1 to 5% by weight of the composition. The weight ratio of cationic surfactant to fatty alcohol is suitably from 10:1 to 1:10, preferably from 4:1 to 1:8, optimally from 1:1 to 1:4.
Conditioners for use according to the invention can include other emulsifiers, conditioning agents, inorganic salts, humectants and similar materials to provide the composition with desirable aesthetic or physical properties. Silicones, as described above for shampoo compositions, are particularly preferred conditioning agents for hair.
As further optional components for inclusion in shampoo or conditioner compositions for use according to the invention, in addition to water, may be mentioned the following conventional adjunct materials known for use in cosmetic compositions: suspending agents, thickeners, pearlescing agents, opacifiers, salts, perfumes, buffering agents, colouring agents, emollients, moisturisers, foam stabilisers, sunscreen materials, antimicrobial agents, preservatives, antioxidants, natural oils and extracts, propellants.
The invention will now be further illustrated by the following, non-limiting Examples.

Method of hair treatment using organic amino compounds

Abstract: (i) basic amino acids;

Abstract: (ii) urea;

Abstract: (iii) guanidine;

Abstract: (v) mixtures of any of (i) to (iv).

Unilever Home and Personal Care USA, division of Conopco, Inc.


The present invention relates to a transmitter for high speed communication systems, comprising a plurality, preferably two, drivers each having series terminating resistor, wherein the series terminating resistors are joined at the transmission line. The drivers are controlled in two modes. In the first mode, a control unit supplies drivers with a signal which is a function of input data, to provide the transmitter drives a communication line with an output impedance equal to the parallel effect of all the terminating resistors. In the second mode, the control unit generates a signal to make the drivers with respective series terminating resistors acting as a parallel termination circuit. No actual data is transmitted in this mode. In a preferable embodiment, to achieve this, one driver or a group of drivers drives one logic level signal, while the other drivers drives the inverse to this signal.

The present invention relates generally to transmitters and transceivers for high speed communication systems and, more particularly, to transmitters for transmitting signals with a controlled impedance load.
Also, the present invention relates to termination circuits and methods therefor. More particularly, the present invention relates to termination circuits that advantageously provides fast and efficient signal transmission via transmission lines in electronic systems.
In the design and implementation of electronic systems particularly those employing integrated circuits, undesired transmission line effects are of a particular concern. As signals travels down transmission lines, e.g., traces on a printed circuit board, reflections may occur on the lines. The reflections are due to, for example, mismatched impedances between the driver circuit and the line, which may cause the signal to reflect back and forth, giving rise to ringing. These reflections and other undesired transmission lines effects are often exacerbated as the operating speed of the signal increases. If left uncorrected, the reflections may cause the signal""s voltage to swing outside of the defined xe2x80x9c0xe2x80x9d or xe2x80x9c1xe2x80x9d voltage levels, thereby causing the receiving device to incorrectly interpret the signal received and generate erroneous results.
To address the impedance mismatch between the driver (or receiver) circuit and the transmission line, a variety of techniques have been known in the prior art.
Typically, high speed communication systems transmit a signal down a line with a terminating voltage and terminating resistance, normally located near the receiver. The effect of the transmitter is to send a fully saturated digital signal into the transmission line at the same impedance as the line itself such that any reflections from impedance anomalies in the line do not cause further reflections from the transmitter. The receiver has a terminating load at the same impedance as the transmission line. The terminating resistances are arranged in very high speed systems to create a terminating voltage that is typically the median of the voltage value of the 1 and 0 of the digital signal.
As shown in FIG. 1, to provide the same preset voltage potential to the load, the conventional transceiver may comprise a resistor 3 incorporated in the bus line after the driver 1 and a terminating resistor 4 incorporated into the receiving circuit.
While this approach is effective for some systems, there are numerous disadvantages. For example, the use of an impedance matching resistor attenuates the signal, which lowers noise immunity while dramatically increasing power dissipation. To illustrate, the presence of resistor 4 forms essentially a resistor divider circuit between the characteristic impedance of the transmission line and resistor 4, thereby lowering the signal""s voltage level at the receiving circuit.
Further, the presence of resistor 4 increases the power dissipation, which increases the load on the driver circuit and causes additional heat to be generated as well as more power from the system""s supply.
The presence of resistor 3 creates a situation in which the input to any other device which might be connected to the transmission line sits at half amplitude, an undesirable condition while the line is settling. Still further, it is often difficult to provide impedance matching for transmission lines whose characteristic impedance may change with the system""s configuration.
Thus, for high speed communication systems, it is complex to provide termination voltages and resistors to transmitters, as a receiver requires the signal with a controlled impedance load linked to a terminating voltage, but the transmitter requires to drive with a series termination into the same line. This causes the increase in swing and power losses and the reduction of the communication speed.
Moreover, contemporary high speed communication systems require quick direct triggering. However, the time required to switch the driver circuit of FIG. 1 into tri-state will be bigger than the time of switching from one logical state to another.
In U.S. Pat. No. 5,781,028, a system and a method are described for a switched termination of a universal serial data bus between first and second devices having transmitting and receiving modes. When the first device is in transmitting mode, a second termination coupled within a receiver circuit at the second end of the bus is activated to terminate the second end; when the first device is in receiving mode, a first termination coupled at this end of the bus is activated to terminate the first end. This arrangement provides for activating the termination at the receiving end only.
However, similar to the prior art already described above, switches used for connecting and disconnecting the resistors will introduce additional errors in the system, as the time required to switch the resistors will be bigger than the time of switching from one logical state to another. This prevents from achieving high speed operation in various applications where timings are critical. In view of the foregoing, there are desired transmitters with improved termination circuits and methods therefor that advantageously provide fast and efficient transmission of signals via transmission lines in electronic systems, particularly signals having low operating voltage ranges, whilst at the same time simplifying the implementation of transceivers in very high speed systems.
The present invention provides a transmitter which avoids or at least alleviates the above mentioned disadvantages of the prior art.
According to one aspect of the present invention, a transmitter comprises a plurality, preferably two, drivers each having series terminating resistor. The transmitter further comprises a control unit provided by a data signal and a control signal.
The control unit operates in two modes. In the first mode, the control unit supplies drivers with a signal which is a function of input data, to provide the transmitter drives a communication line with an output impedance equal to the parallel effect of all the terminating resistors.
In the second mode, the control unit generates a signal to make the drivers with respective series terminating resistors acting as a parallel termination circuit. No actual data is transmitted in this mode. In a preferable embodiment, to achieve this, one driver or a group of drivers drives one logic level signal, while the other drivers drives the inverse to this signal.
This means that if all drivers drive a data signal, which, in general, may not be the same for all drivers, then the signal is transmitted with an impedance equal to the parallel effect of all the terminating resistors. For example, if there are two drivers and each resistor is 100 Ohms, then driving the two in parallel will create a 50 Ohm drive impedance into the transmission line.
If the drivers drive complementary signals, that is, for example, one driver is high and the other is low, then a potential divider is formed which has an impedance of 50 Ohms and acts as a terminating resistance and terminating voltage to the receiver.
In another aspect, a method of high speed data transmission is provided, the method comprising the steps of:
(a) providing a plurality of drivers each having series terminating resistor, wherein the resistors are connected at a common point;
(b) providing a data signal;
(c) providing a control signal defining two modes of operation:
(d) in a first mode, a control unit supplies drivers with a signal which is a function of input data, to provide the plurality of drivers drives a communication line with an output impedance equal to the parallel effect of all the terminating resistors;
(e) in a second mode, the drivers are provided with a signal that makes the drivers with respective series terminating resistors acting as a parallel termination circuit, while no actual data is transmitted in this mode.
Preferably, the series terminating resistors are joined at the transmission line.
In case of two drivers, in the first mode they both drive the same signal. In the second mode, the drivers drive different, e.g. complementary, signals, i.e. one driver drives one logic level signal, while the other driver drives the inverse to this signal, thereby, a terminating voltage is formed as a half sum of high and low signal levels (for two equal series resistors).
The combination of the above features enables true synchronous operation of bi-directional communication channels, such as in chip-to-chip communications.

Transmitter with active differential termination


An electro-optical device includes data lines divided into groups of M data lines, where N is a natural number equal to or greater than three. Output lines are arranged in correspondence with the data lines and receive, during a predetermined period, output of a correction voltage having a predetermined voltage level and sequential data voltages for defining gray scale levels of the pixels. A time division circuit simultaneously supplies the correction voltage output to the output line to M data lines of each group of data lines, where M is a natural number equal to or greater than two and equal to or less than “N−1”.

1. Technical Field
The present invention relates to technical fields of an electro-optical device such as a liquid crystal device, a method of driving the electro-optical device, and an electronic apparatus such as a liquid crystal projector having the electro-optical device.
2. Related Art
In electro-optical devices of this type, parasitic capacitance exists between a data line to which a data voltage for regulating a gray scale level of a pixel is supplied and a pixel column connected to the data line. The data line and the pixel column form capacitance coupling through the parasitic capacitance, and there is a case where vertical crosstalk (uneven display in a direction along the data line) is generated due to the capacitive coupling and the like during the operation of the device. In addition, there is a case where the vertical crosstalk is generated due to a gradual variance of a voltage level maintained in a pixel which is influenced by a leakage current (off leak) in a state that a pixel transistor is turned off.
In order to suppress the vertical crosstalk, for example, a method of driving an electro-optical device in which before a data voltage is supplied, a voltage (correction voltage) level having a polarity opposite to that of the data voltage is supplied to a data line in one horizontal scanning period has been disclosed in JP-A-6-34941.
In addition, in JP-A-2005-43417, technology for sequentially supplying a correction voltage level to a plurality of data lines, one at a time has been disclosed. Furthermore, in JP-A-2005-43418, technology for simultaneously supplying a correction voltage to a plurality of data lines has been disclosed.
However, in the above-described technology for sequentially supplying the correction voltage level to a plurality of data lines, one at a time, there are technical problems that a considerable time is required for supplying the correction voltage level to the whole plurality of data lines and that a drive voltage level increases. On the other hand, in the technology for simultaneously supplying the correction voltage level to the plurality of data lines, there is a technical problem that it is difficult to supply correction voltage levels appropriate to the plurality of data lines.

Electro-optical device, method of driving electro-optical device, and electronic apparatus


A method, system, and computer program product are provided for communicating to a powered element in a rack system. A controller injects communication data onto power lines that provides power to a plurality of powered elements. The powered elements determine if the communication data transmitted via the power lines should be used for configuration using an address embedded within the communication data. The powered elements compare an embedded target address within the communication data to the address of the particular element. If there is a match between the addresses, the corresponding powered element processes the communication data to configure the powered element. As a result, data may be communicated over the power lines thereby eliminating the need for separate communication lines. Thus, the amount of cables required to interconnect the powered elements of the distributed data processing system may be reduced by eliminating the communication lines from the system configuration.

1. Technical Field
The present application relates generally to data processing system communications. More specifically, the present application is directed to data processing system communications using a fault tolerant closed system control.
2. Description of Related Art
Large scale rack mounted data processing systems, such as enterprise class data processing systems, require numerous cables to interconnect the various elements of the system together. For instance, a relatively small system may contain over a hundred cables while higher-end systems may contain thousands of cables. Not only is the routing of cables difficult, it is also very expensive, provides many failures points, and requires stocking of numerous field replaceable units. As systems grow so does the cabling, especially in redundant systems where there is often a need for two cables for each of power and communications per element to handle the high failure rates inherent to a mechanical design.
An example of the complexity in interconnecting a data processing system may be a system of eight elements that requires both primary and redundant communications and power cabling. For each element, there is a primary power cable, a redundant power cable, a primary communication cable, and a redundant communication cable. Thus, the system of eight elements requires 32 cables. Additionally, using primary and redundant communications requires a separate Ethernet switch for the primary communication system and the redundant communication system. As stated previously, such cabling increases cost, causes housings to be larger to accommodate extra cabling, provides failure points in the system, etc. These problems are increased with larger systems requiring even more cabling. Therefore, a need exists to reduce the cumbersome interconnection of data processing systems.

Fault tolerant closed system control using power line communication

International Business Machines Corporation


The present invention is directed to an apparatus for providing convenient control of a power tool electrical system. A switch assembly of the present invention includes a first actuator and a second actuator, which is disposed remotely from the switch and first actuator. The second actuator is connected via a coupling device, such that user manipulation of either the first or second actuator is capable of controlling electricity flowing to the motor. Including a second actuator may permit the user to retain greater control over the tool when turning the power on or off. In additional exemplary aspects, a coupling device included in the switch assembly is configured and arranged so as to prevent inadvertent damage to the power tool such as by accidental engagement of a shaft lock while the motor is operating.

Power tools are routinely employed to reduce time and effort required for a task, while increasing the quality of craftsmanship for the user. Convenient usage may be a determining factor in a user's decision to purchase a particular tool. In order to satisfy user demands, tools should allow the user a wide range of functionality, be ergonomically configured, and promote user control.
Woodworkers are among some of the most demanding power tool users. To an experienced woodworker the quality of the finished product is a reflection of the tools and techniques employed to finish the task. Previously, routers, and in particular removable base routers, included a single switch mounted on the motor housing for controlling the router's electrical system. This configuration permits the user to employ different bases such as a fixed base, a plunge base, and the like. A drawback to this switch arrangement is that a user may have to use one hand to hold a knob type router handle while using their free hand to turn on or off the switch. Further, routers such as these typically utilize a switch mounted opposite the base which may be difficult to reach when rasping either the motor housing and/or the main portion of the base. Again, the user may be forced to hold the motor housing with one hand while turning the electrical system on or off.
Since routers may accept a wide variety of bits, users often change bits repeatedly. Furthermore, bit changes may be time consuming as a user is forced to position the newly selected bit to the desired depth. For example, a user may use a strait cutting bit to form a rabbit for a shelf and then, wish to switch to a dovetail bit to dovetail a drawer. Therefore, a wide variety of methods are employed to facilitate bit changes. For instance, two wrenches may be utilized to remove a collet and bit assembly. In other instances, drive shaft locks may be utilized to prevent rotation of the shaft when changing bits. Changeing router bit utilizing a shaft lock may be difficult as the shaft lock is positioned adjacent the collet, thereby requiring a user to depress a drive shaft lock while manipulating the collet with a wrench.
Therefore, it would be desirable to provide a switch assembly for conveniently activating and deactivating a power tool electrical system, and particularly, a switch assembly for routers.


According to the invention, different coloured and/or different types of flocks (8, 9) are applied to cover or flock-coat profiled joints or other profiled sections (11) in predetermined areas in a coating station (3) at the very moment when the required holes and separating cuts are made in the cutting and drilling station (4). The flock cabin (10) is divided up in to partial cabins (15, 17, 19) by means of partitions (16, 18) which can be displaced in a corresponding manner towards the profiled section (11) or brought tightly against it. Instead of the above-mentioned partitions (16, 18) or in addition to the partitions (16, 18), axially separating partitions (29, 30) extending in a longitudinal direction of the profiled section (11) are provided. The inventive method enables various coating areas (35, 36, 37) to be obtained on one single profiled section. This makes it possible, for instance, to adapt precisely defined areas, e.g., joint elements in a car body, to the colour of the car or fittings.

The invention concerns a process for applying different colored flocks and/or types of flocks to a profiled section of profile serving especially as an automobile body into which, after extrusion, the flock is deposited and bore holes and separation cuts are introduced. The invention furthermore concerns a device for implementing the process with coating, cutting to size and drilling as well as drying and cleaning stations connected with the extruder and which are joined with each other over a transport and guide facility for the profile, whereby the coating station has available storage space for the flock as well as a flock cabin.
Sections of this type, especially profiled joints, are generally made of plastic, whereby the elements of the section which do not serve for sealing or for other tasks are coated with flocks of a color which, for example, is adapted to the color of the automobile, or which corresponds thereto. This is especially advantageous with rubber sections, which as a rule have a black color, because they clearly contrast these black profiled joints from the color of the automobile or the color of the interior space of a vehicle. The flocks are applied in a coating station to the section, whereupon the section cord runs through a drying station and then is cut to length and provided with the necessary bore holes. It is disadvantageous that with the previous processes and with the devices provided for these that coating is possible only with one type of flock or one color, whereby the change from one type of flock to another or a corresponding change in color requires considerable conversion operations. Coating here takes place on the running section cord, which then must be stopped for a short time in the cutting and boring station in order to be able to introduce the separation cutting or the boring. It is consequently not possible to undertake different coatings of sections of this type in stages or subdivided in another manner.
Underlying the invention is therefore the object of creating a process and a device with which sections in exactly defined regions are to be provided with a different color and/or constructed flock coating.
This objective is accomplished in accordance with the invention in that the flock is deposited into the still-standing section simultaneously with the production of the bore holes and separation cuttings, and subdivided into previously set coating areas kept separate from one another.
With a process of this type, it is first of all possible to apply a different color or a different type of flock to various coating areas of the section at the same time and to be sure that they are precisely separated from one another because the coating takes place at exactly the moment in which the section must be detained on account of the necessary application of the bore holes and separating cuts. Owing to the defined areas which must be adhered to with great precision, there exists the possibility of applying, for example, red or blue or green or other color flocks to a specified component area of a profiled segment, while the adjoining area is provided with a wholly different color coating. Flocks also applied to prevent sticking capacity may, for example, be installed in different colors in the sealing area of a car frame profiled joint perpendicular to the longitudinal axis, or even in the direction of the long axis, in order thus to comply with necessities or even taste. Further details on this have yet to be explained further in which connection it is decisive that the respective coating areas can be kept precisely separated from each other.
According to an appropriate construction of the invention, it is provided that the deposition of the flock is undertaken into the still-moist adhesive bed of the section. The coating station is for this reason to be arranged immediately behind the extrusion station, whereby the adhesive bed is at the same time rapidly normalized by applying the flock so that under certain circumstances a subsequent drying and cleaning station is not necessary.
It has already been mentioned further above that the corresponding coating areas can have separation lines as they correspond to the respective requirements. The invention therefore provides that the flocks are applied to the section separately with respect to color and/or type transverse to and/or along the section. Supplementally, the invention provides that the coating areas are partitioned from each other with flock bombardment of various colors or different types in the longitudinal direction of the section and/or across the section. Through a corresponding partitioning, that is, in lowering the separation walls until they are right on the section, it is assured that the respective border areas remain clearly separated from each other, even if, for example, red and green flocks are to be applied in appropriately adjacent coating areas. A mixed coating does not occur unless such is specifically desired from the customer in question. The possibility of specifying and adhering to clear boundaries here results in considerable advantages.
With relatively thin coating of sections, but also with high grade sections, it is advantageous if the continuously guided section is further conditioned following coating with different flocks in a drying and cleaning station. Subsequently, cutting to length or application of bore holes takes place in order to prepare the individual segments appropriately for the respective use. First to generate clear and clean border areas and secondly to be able to assure a complete utilization of the flocks, it is provided that excess flocks are sucked off separated according to color and/or type and in any given case fed into a selected storage space. As a rule, it is a matter of the same storage area which is allocated to the respective coating segment. The excess or remaining flocks are consequently put into circulation and applied, if need be, to the section in connection with the next bombardment.
A device in connection with which the flock cabin is subdivided into separate component cabins by separation walls lowered to the section serves to implement the process, which are in any given case proportioned lengthwise corresponding to the length of the segments of the section to be coated with different flocks and the transport facility is comprehensively configured with section so that each component cabin is allocated a storage space and that the transport facility and the flock discharges of the flock cabin are constructed by alternate activation. By selecting the term xe2x80x9cflock cabinxe2x80x9d for the basic part of the device, it has already been made clear that it is a matter of a closed and quasi-partitioned unit in which the coating takes place. This flock cabin is or can be subdivided into different component cabins in order to specify different coating segments perpendicular to the long axis of the section or, as further explained above, in the longitudinal direction as well. The section to be coated runs into the flock cabin or its component cabins, whereupon at the same time the coating of the different segments is undertaken the flock provided in each case for this purpose. When detaining the section that is thus in connection with halting the transport facility, flock discharges of the flock cabins or component cabins are activated which in the same moment bombard the still-moist adhesive bed of the section with flock. If the boring and cutting to length operations are concluded, the coating is also finished and the flock discharges from the flock cabin are stopped when the transport facility starts again. Since the size of the component cabins is specified in advance, an exact adherence to the separation cuttings can be maintained in this way for the different types of flock or colors of flock.
According to a further appropriate construction, it is provided that the partitions of the component cabins are constructed displaceable individually and/or in groups in the longitudinal direction of the section. This way, the dimensions of the component cabins can be changed practically at will, and the coating segments can therewith also be altered in their lengths. There also exists the possibility, however, of adapting the coating station to the requirements in its overall position. It is clear that a change of the coating segments is possible not only in the longitudinal direction of the section, but also crosswise in relation to this.
In order to prevent some flocks from reaching the environment when bombarding the profile with them, the invention provides that the component cabins are constructed enclosing the section and the section fixing element of the transport facility. The component cabins or the flock cabins thus represent overall a closed unit which can be altered as described in its position and component lengths, which, however, always ensures that the coating process transpires as a complete operation.
In order to be able to adhere to the coating segments in the longitudinal direction of the section as well, it is provided in accordance with the invention that the component cabins are outfitted with axial partitions running parallel to the long axis of the section. These axial partitions, which correspond to the separation lines in the construction, ensure that, viewed from the size of the section, coating segments of different color or different type can also be maintained. In this connection, it is also of advantage if axial partitions are provided in addition to the separation walls whereby they are displaceable separately in direction on the section, or are to be pulled away from these, so that corresponding to the needs in any given case, different coating segments are attained and can be adhered to without an extensive conversion of the entire flock cabin becoming necessary.
A further optimization of the adaptability of the device of the invention is reached in that several flock cabins are provided one behind the other or at a distance to one another, encompassing a segment of the section. By shutting off or cutting in flock cabins appropriately separated from one another, a further variation possibility is attainable in connection with coating sections.
It was already pointed out above that it is appropriate for several reasons not to discharge the remaining flocks into the environment, but rather to make them available for a renewed bombardment. This is attained in accordance with a construction of the invention, since below the horizontal separating wall of the component cabins, collection rooms for the remaining flocks are arranged and connected with the allocated storage spaces. Either a corresponding amount of remaining flock can first of all be collected in the collection rooms and then conveyed into the storage space, or there also exists the possibility of continuously blowing in the remaining flock over the collection room into the respective storage space.
An especially intimate connection of flocks with the section is attained if the bombardment takes place on the still-moist adhesive bed. This can be guaranteed if, as provided in accordance with the invention, the section fixing element of the transport facility is constructed holding the section with the still-moist adhesive bed facing the flock discharges. Also, with a running or stopped section, a sliding and therewith a twisting of the still-moist adhesive bed is thus avoided. The section fixing element always aligns the corresponding area of the section exactly such that the surface of the section and the flock discharges ensure an exact bombardment.
The invention is in particular distinguished by the fact that a process as well as a device are created with which sections can be coated in exactly defined coating areas with different color or different type flocks. At the same time, the invention makes use of the fact that the section must in any case be detained for a short period of time during its conditioning process owing to the necessary cutting to length and creation of bore holes. Exactly at this moment, the bombardment of the section with flocks takes place in the coating station, and therewith an optimal construction of corresponding sections in particular usable as car frame sealing. The coating station is integrated into the extrusion length or forms a unit with this and the further stations so that the entire conditioning process can be conducted meticulously in detail. The section to be coated is conducted into the appropriate station by means of the transport facility, whereby the transport facility stops for a short time upon reaching a defined position. Here the machining period for drilling and cutting the section are utilized. In this waiting position, the different color or different type flocks are deposited on the areas previously set. Following this process, the transport facility is set into operation again, and the next area to be coated moves into the station. The already-coated part of the section runs through the further stations so that subsequently an exactly specified segment of the section stands available for use. The flocking facility is designed so that it can contain an unlimited length of an infinite number of colors. For example, it is possible to adapt exactly defined areas to the automobile or equipment color in connection with a car frame sealing.
Further details and advantages of the object of the invention emerge from the following description of the associated drawing in which a preferred embodiment with the details and individual components necessary for this is represented, wherein:

Method and device for applying different colored flocks to profiled joints


A container transport apparatus for transporting a shipping container between two locations, such as between residences or business locations, includes a front unit and a separate rear unit for supporting the respective forward and rear ends of the shipping container. The front and rear units each include a frame structure with upper and lower hydraulically extendible vertical arm members. Locking pins on the vertical arm members engage sockets on the corners of the shipping container to facilitate vertical lifting and support of the container above the ground without tilting the container, thereby preventing damage to articles packed in the container. A forwardly extending trailer tongue on the front unit attaches to a hitch of a towing vehicle. The rear unit is provided with drive wheels and steering wheels for maneuvering the rear unit into position against the rear end of the container. The rear unit is also provided with inflated road tires to enable towing of the apparatus by a motor vehicle with or without a storage container supported between the front and rear units.

1. Field of the Invention
The present invention relates to a container transport system and, more particularly, to an apparatus including separate front and rear units for lifting and supporting a shipping container above a ground surface for subsequent towing between two locations.
2. Discussion of the Related Art
Having to pack, transport and unload all of one""s personal belongings (i.e., furniture, equipment, tools, clothing, etc.) when moving to a new residence or place of business can be extremely stressful and exhausting, particularly when attempting to do so in one day. Typically, when moving to a new address, articles or packages are hand carried, individually, onto a truck for transport from the old address to the new address. When each article is hand carried out of the old address, one or more individuals carrying the articles are required to lift the article or carry it up a ramp onto the truck. Once in the truck, the article is moved and manipulated into position in a manner which uses the space most efficiently. This process is repeated until all of the articles from the old address are packed onto the truck. During this entire packing process, the truck remains idle. Due to the significant daily expense in renting and/or operating the moving truck, there is a definite sense of urgency on the part of the movers to load the truck as quickly as possible, typically in less than one full day, so that the truck and moving crew can move on to the new address for unloading.
When arriving at the new address, the articles being transported are again individually carried off of the truck and into the new address. And, again, this laborious and exhausting task is carried out at a hurried pace so that the emptied truck can be returned or moved on to a new moving job on a cost-efficient schedule.
Unfortunately, in the hasty and somewhat careless process of loading and unloading a moving truck, furniture and other articles are sometimes damaged. Often, movers become fatigued, especially towards the end of the day, at which point mistakes are more likely to result in injury and damage to furniture and other valuable articles.
In view of the foregoing problems associated with moving furniture, equipment and other articles from one location to another, there remains an urgent need for a system and apparatus which enables a shipping container to be dropped off at a person""s home or business and packed at a more leisurely, careful and less stressful pace, while permitting the transport vehicle to move on to another location so that revenues are not lost. More particularly, there is a need for a system and apparatus which can be used to transport a shipping container to a person""s house or place of business, and to leave the shipping container on the ground to be filled at the person""s leisure for subsequent moving to a new location. There is a further need for a system and apparatus which is able to lift the loaded container vertically without tilting the container and damaging the articles loaded therein, and to subsequently transport the container to a new address where it can be vertically lowered and placed on the ground for unloading at the person""s leisure.
The present invention is directed to a container transport apparatus for transporting a shipping container between two locations, such as between residences or business locations. The front and rear units each include a frame structure with upper and lower hydraulically extendible vertical arm members. Locking pins on the vertical arm members engage sockets on the corners of the shipping container to facilitate vertical lifting and support of the container above the ground without tilting the container, thereby preventing damage to articles packed in the container. A forwardly extending trailer tongue on the front unit attaches to a hitch of a towing vehicle. The rear unit is provided with drive wheels and steering wheels for maneuvering the rear unit into position against the rear end of the container. The rear unit is also provided with inflated road tires to enable towing of the apparatus by a motor vehicle with or without a storage container supported between the front and rear units. The apparatus includes a front unit and a separate rear unit. The front and rear units each include a frame structure with upper and lower hydraulically extendible vertical arm members. Locking pins on the vertical arm members engage sockets on the corner of the shipping container to facilitate vertical lifting and support of the container above the ground without tilting the container, thereby preventing damage to articles packed in the container. A forwardly extending trailer tongue on the front component attaches to a hitch of a towing vehicle. The rear component is provided with ground engaging wheels for towing the apparatus with or without a storage container supported between the front and units.


The invention provides a lithographic printing for precursor having an imagable coating on an aluminum support, wherein the imagable coating comprises a polymeric substance comprising colorant groups, and wherein the aluminum support on which the coating is provided is anodized but not subsequently modified by means of a post-anodic treatment compound, and the coating does not comprise a colorant dye. The polymeric substance may also comprise pendent infra-red or developer dissolution inhibiting groups, and these groups may also be the colorant groups themselves.

This invention relates to lithographic printing forms and to precursors thereto, having aluminum supports bearing imagable coatings. The invention relates further to the manufacture of such precursors, and their use.
Typical lithographic printing form precursors are prepared as follows.
Aluminum sheet is subjected to a graining or roughening treatment. This may be a mechanical graining treatment, for example brush graining or ball graining, or an electrograining treatment (also called electrochemical etching or electrochemical roughening) in a mineral acid. The sheet is then anodised, to provide a hard hydrophilic surface, which has a microporous xe2x80x9choneycombxe2x80x9d structure. Anodising may typically take place in a sulphuric acid or phosphoric acid electrolyte. A post-anodic treatment (PAT) is then carried out, using, for example, a silicate or a phosphate composition. Subsequently a different composition, containing a polymeric substance, is applied in a liquid form, a solvent being removed therefrom to leave the imagable coating as a dry film on the aluminum sheet, which may be cut into individual lithographic printing form precursors. The resultant precursors may be imaged and developed, to provide the lithographic printing forms which are printed from. During development, portions of the coating are selectively removed. In positive working systems portions which were exposed are removed. In negative working systems portions which were not exposed are removed. In most systems, whether positive or negative, the remaining portions of the coating are preferentially ink-accepting.
Many coatings contain dyes and these may be employed for several distinct reasons. A dye may alter the properties of the polymeric substance, for example by rendering it insoluble in a developer, but such that after imaging, the coating is soluble in the developer. Examples of such dyes are given in PCT/GB97/39894. A dye may function as an absorber of imaging radiation, either as a xe2x80x9cspectral sensitizerxe2x80x9d, to emit radiation of a different wavelength which triggers a desired chemical reaction to alter the properties of the coating, or as a compound which converts the absorbed radiation to heat, which alters the properties of the coating. Examples of dyes functioning as spectral sensitizers are given in U.S. Pat. No. 5,200,292. Examples of dyes converting imaging radiation to heat are given in PCT/GB97/39894. Additionally, a dye may be used to color a coating, with the result that after development a positive or negative image can be seen on the printing plate, from the color contrast. From this the printer can gain an impression of whether imaging and development has been successful and can identify and correct faults.
If the PAT step is not carried out colored dye present in the coating may be seen in the regions from which the portions of the coating are removed on development; the dye may form an absorbed or residual layer on the anodised surface. This is undesirable as it reduces the color contrast between exposed and unexposed portions of the printing plates and makes it harder for the printer to determine whether imaging and development has been successful, and to identify and correct faults. Furthermore dye which is present in uncoated areas may attract ink and cause poor printing performance.
The invention relates to the use in a lithographic printing form precursor of a polymeric compound comprising pendent colorant groups. This gives the required color contrast. Free colorant dye is not needed and it is not necessary to employ a PAT step, in the preparation of an aluminum lithographic support.
In accordance with a first aspect of the present invention there is provided a lithographic printing form precursor having an imagable coating on an aluminum support, wherein the imagable coating comprises a polymeric substance comprising colorant groups, wherein the aluminum support on which the coating is provided is anodized but not subsequently modified by means of a post-anodic treatment compound, and wherein the coating does not comprise a free colorant dye.
Such a polymeric substance of the invention is referred to herein as a xe2x80x9ccolorant tagged polymerxe2x80x9d.
By xe2x80x9ccolorant dyexe2x80x9d we mean a dye which reduces the color contrast between exposed and unexposed portions of a printing plate after development of the plate, when retained on the developed plate. By xe2x80x9cfree colorant dyexe2x80x9d we mean a colorant dye which is not pendent on the polymeric substance.
The term xe2x80x9caluminumxe2x80x9d as used herein includes aluminum alloys.
Preferably both sides of the aluminum sheet are anodised, to reduce the risk of corrosion attack in a developer.
Preferably a graining step is carried out prior to the anodising step, for example mechanical graining or electrograining, as described briefly above. Preferably electrograining is carried out. The anodising step which follows may suitably take place in a phosphoric acid or, especially, a sulphuric acid electrolyte. The technology of graining and anodising is very well known to the skilled person but if background information is needed, the reader may refer to xe2x80x9cThe Surface Treatment and Finishing of Aluminum and its Alloysxe2x80x9d, S. Wernick et al, 5th edition; 1987,ISBN 0-904477-09-6, pp 184-189.
As well as avoiding staining and removing a manufacturing step we have found that the printing form precursors of the invention yield, after steps of imaging and development, printing forms which have longer run lengths than similar printing forms, employing a polymeric substance without colorant groups thereon, employing an admixed colorant dye, and which have had a post-anodic chemical treatment step.
A precursor made by a method in accordance with the invention may have a coating formed as a single layer or as two, or more, layers.
In accordance with the examples herein good results were found with positive working compositions, which are preferred embodiments of the invention, but a precursor made by a method in accordance with the invention may be positive working or negative working.
Preferably the corresponding polymeric substance without any pendent colorant groups (referred to herein as the parent polymer), has nucleophilic groups Y, able to react with a colorant compound or moiety, having a halogen atom, for example a chlorine atom. Preferably the parent polymer has groups Y selected from xe2x80x94SO2NHR, xe2x80x94NHR, xe2x80x94SH and xe2x80x94OH, where R represents a hydrogen atom or a C1xe2x80x944 alkyl group, for example a methyl group. Preferably R represents a hydrogen atom. More preferably the parent polymer has sulfonamido groups or hydroxyl groups Y, or both.
Since it is unlikely or undesirable, or both, that all such groups of the parent polymer are functionalized by the reaction, preferably the colorant-tagged polymer also has such groups Y. Most preferably, the parent polymer has hydroxyl groups Y.
A hydroxyl group-containing polymer, useful as a parent polymer may comprise a phenolic resin or co-polymer thereof. Other polymers suitable as parent polymers include poly-4-hydroxystyrene; copolymers of 4-hydroxystyrene, for example with 3-methyl-4-hydroxystyrene or 4-methoxystyrene; copolymers of (meth)acrylic acid, for example with styrene; copolymers of maleiimide, for example with styrene; hydroxy or carboxy functionalised celluloses; dialkylmaleiimide esters; copolymers of maleic anhydride, for example with styrene; and partially hydrolysed polymers of maleic anhydride.
Particularly useful phenolic resins in this invention are the condensation products from the interaction between phenol, C-alkyl substituted phenols (such as cresols and p-tert-butyl-phenol), diphenols (such as bisphenol-A) and aldehydes and ketones (such as formaldehyde and acetone). Depending on the preparation route for the condensation a range of phenolic materials with varying structures and properties can be formed, as will be well understood to those skilled in the art. One useful class is pyrogallol/acetone condensates. Particularly useful in this invention are novolak resins, resole resins and novolak/resole resin mixtures. Most preferred are novolak resins. Examples of suitable novolak resins have the following general structure:
where the ratio of n:m is in the range of 1:20 to 20:1, preferably 3:1 to 1:3. In one preferred embodiment, n=m. However, in certain embodiments n or m may be zero. Novolak resins suitable for use have a molecular weight in the range of about 500-20,000, preferably in the range of about 1000-15,000, preferably about 2500-10,000.
Novolak resins useful in this invention are suitably condensation reaction products between appropriate phenols, for example phenol itself, C-alkyl substituted phenols (including cresols, xylenols, p-tert-butyl-phenol, p-phenylphenol and nonyl phenols), diphenols (e.g. bisphenol-A (2,2-bis(4-hydroxyphenyl)propane)), and appropriate aldehydes, for example formaldehyde, chloral, acetaldehyde and furfuraldehyde. As will be well understood by those skilled in the art, the type of catalyst and the molar ratio of the reactants used in the preparation of phenolic resins determines their molecular structure and therefore the physical properties of the resin. An aldehyde: phenol ratio between 0.5:1 and 1:1, preferably 0.5:1 to 0.8:1 and an acid catalyst is typically used to prepare novolak resins, which are thermoplastic in character. Higher aldehyde:phenol ratios of more then 1:1 to 3:1, and a basic catalyst, give rise to resole resins, and these are characterised by their ability to be thermally hardened at elevated temperatures.
The hydroxyl group-containing polymer may comprise a polyhydroxystyrene resin or co-polymer thereof, of general formula:
wherein R1 represents a hydrogen atom or alkyl group, R2 represents a hydrogen atom or alkyl group, R3 represents a hydrogen atom or alkyl group, R4 is an alkyl or hydroxyalkyl group, and the ratio n/m is in the range 10/0 to 1/10.
In general terms, any alkyl group is suitably a C1-12 alkyl group, preferably a C1-6 alkyl group, especially a C1-4 alkyl group. An alkyl group may be branched (for example t-butyl) or straight chain (for example n-butyl).
R1 preferably represents a hydrogen atom or a C1-4 alkyl group, especially a methyl group. Most preferably R1 represents a hydrogen atom.
R2 preferably represents a hydrogen atom or a C1-4 alkyl group, especially a methyl group. Most preferably R2 represents a hydrogen atom.
The hydroxy substituent of the phenyl group shown is preferably located para to the linkage of the phenyl group to the polymer backbone. R3 preferably represents a hydrogen atom or a C1-4 alkyl group, especially a methyl group. Most preferably R3 represents a hydrogen atom.
R4 preferably represents a C1-6 alkyl or C1-6 hydroxyalkyl group. When it represents a hydroxyalkyl group the hydroxy group is preferably carried by the terminal carbon atom of the alkyl group. Examples of suitable groups R4 are xe2x80x94CH3, xe2x80x94CH2CH2OH, and xe2x80x94CH2CH2CH2CH3. Preferably the ratio n/m is in the range 10/1 to 1/10, preferably 5/1 to 1/2. More preferably the ratio n/m is in the range 2/1 to 2/3. Most preferably the ratio n/m is in the range 3/2 to 2/3, especially 1/1.
The weight average molecular weight Mw of the polyhydroxystyrene polymer drawn above, as measured by gel permeation chromatography, is preferably in the range 5,000-75,000, especially 7,000-50,000. The number average molecular weight Mn of the polymer is preferably in the range 2,000-20,000, especially 3,000-8,000.
The colorant-tagged polymer may be prepared from the parent polymer by reaction between the colorant moiety or compound, having a reactive halogen atom, and the parent polymer, under standard conditions to promote the required dehydrohalogenation. Typically alkaline dehydrohalogenation will be effective, at an elevated temperature, suitably under reflux. For example, the colorant-tagged polymer may be prepared by reacting an appropriate parent polymer with a dye having a labile halogen atom, under alkaline conditions at an elevated temperature, to promote dehydrohalogenation. The same method may be used to introduce other pendent groups of the type previously described, in embodiments in which such groups are present.
Preferably the reaction is carried out such that nucleophilic groups Y remain. After reaction the number ratio of remaining nucleophilic groups Y to colorant groups X, in the resultant colorant-tagged polymer, is suitably at least 2:1, preferably at least 5:1, more preferably at least 10:1. Suitably the ratio does not exceed 100:1. Preferably it does not exceed 50:1. Most preferably it does not exceed 40:1.
The colorant property of the colorant-tagged polymer is preferably effected by pendent colorant groups on the polymer. Such groups may be chromophores per se. Alternatively the colorant property may be brought about by colorant groups pendent on the polymer, and functioning as chromophores through interaction with the polymer.
Colorant compounds or moieties suitable for use as colorant groups on the colorant-tagged polymer are quaternized nitrogen-containing triarylmethane dyes, including Crystal Violet (CI basic violet 3), Victoria Blue and Ethyl Violet; quaternized heterocyclic compounds, including Monazoline C, Monazoline O, Monazoline CY and Monazoline T, all of which are manufactured by Mona Industries quinolinium compounds, such as 1-ethyl-2-methyl quinolinium iodide and 1-ethyl-4-methyl quinolinium iodide, benzothiazolium iodide, and pyridinium compounds such as cetylpyridinium bromide, ethyl viologen dibromide and fluoropyridinium tetrafluoroborate.
Other compounds or moieties useful as colorant groups on the colorant-tagged polymer include Methylene Blue (CI Basic blue 9), polymethine dyes, cyanine dyes, Acidic Orange (CI Solvent orange 15) and a dye having the cation
Useful quinolinium or benzothiazolium compounds are cationic cyanine dyes, such as Quinoldine Blue and 3-ethyl-2-[3-(3-ethyl-2-(3H)-benzothiazolyidene)-2-methyl-1-propenyl]benzothiazolium iodide, and the compound having a cation of formula
Suitably the colorant-tagged polymer may include additional functional groups which act as infra-red absorbing groups.
A colorant-tagged polymer useful in positive working compositions of this invention preferably has at least one pendent colorant group which is also an infra-red absorbing group, and the polymer initially does not dissolve in a developer liquid. However, when the polymer is subjected to infra-red radiation and/or heat, the polymer dissolves in the developer liquid. In one preferred embodiment, the polymer has functional groups independently selected from xe2x80x94SONHR, xe2x80x94NHR, xe2x80x94SH and xe2x80x94OH, where R is H or a C1-C4 alkyl group, and the polymer additionally has pendent colorant groups which absorb infra-red radiation, such as polymethine dye and cyanine dye residues. The polymer may be prepared by reacting a parent polymer with a colorant compound which also acts as an infra-red absorbing compound.
The composition may additionally or alternatively comprise free infra-red absorbing compounds not pendent on the colorant-tagged polymer. Or course any separate infra-red absorbing compound should not be a colorant dye, but is either colorless or has such weak color that it will not affect the color contrast after imaging and development.
Suitably the colorant-tagged polymer includes functional groups which cause the developer solubility of the polymer to be lower than that of a corresponding polymer without such functional groups, but such that the developer solubility of the polymer is increased on exposure to heat and/or infra-red radiation. Preferably the functional groups are also colorant groups. Said functional groups are hereinafter called xe2x80x9creversible insolubilizer groupsxe2x80x9d.
Reversible insolubilizer groups may include pendent functional groups carried by the polymer, additional to the colorant-tagged groups. The reversible insolubilizer groups may be additional to or alternative to any infra-red absorbing groups present on the colorant-tagged polymer. Suitable functional groups include those described in WO 99/01795, the contents of which are hereby incorporated in this specification by reference. Preferred groups are xe2x80x94Oxe2x80x94SO2-tolyl, xe2x80x94O-dansyl, xe2x80x94Oxe2x80x94SO2-thienyl, xe2x80x94Oxe2x80x94SO2-naphthyl and xe2x80x94Oxe2x80x94COxe2x80x94Ph.
Alternatively or additionally diazide functional groups may be carried by the polymer. When diazide groups are used in this invention, either in separate compounds admixed with the colorant-tagged polymer or as functional groups on the colorant-tagged polymer, as described above, they preferably comprise diazo groups (xe2x95x90N2), preferably conjugated to carbonyl groups, preferably via an aromatic or heteroaromatic ring.
In such moieties a carbonyl group is preferably bonded to the aromatic or heteroaromatic ring at an adjacent ring position to the diazo group. Preferred moieties are o-benzoquinonediazide (BQD) moieties (often referred to as o-quinonediazides) and o-naphthoquinonediazide (NQD) moieties.
A BQD moiety may, for example, comprise the 1,4- or, preferably 1,2-benzoquinonediazide moiety. An NQD moiety may, for example comprise the 1,4-, 2,1- or, most preferably, the 1,2-naphthoquinone diazide moiety. Generally, NQD moieties are preferred to BQD moieties, when diazide groups are used in the practice of the invention. The most preferred diazide moiety for use in the practice of this invention is the 1,2-naphthoquinonediazide moiety.
Preferably, however, the precursor does not contain any moieties which render it photosensitive to ambient electromagnetic radiation in the range 190 to 500 nm, preferably 190 to 700 nm. Thus, it preferably is insensitive to ambient visible and ultra-violet light.
The term xe2x80x9cinsensitive to ambient visible and ultra-violet lightxe2x80x9d means that the precursor does not undergo any substantial chemical or physical changes caused by ambient visible or ultra-violet light, which would diminish the imaging or development or printing performance of the precursor.
Preferred reversible insolubiliser groups may include infra-red absorbing groups. Thus, a preferred colorant-tagged polymer of the invention comprises functional groups X which act to inhibit the dissolution of the colorant-tagged polymer compared with the parent polymer, to absorb infra-red radiation and thereby yield heat, and to permit the colorant-tagged polymer to dissolve in the developer liquid, where thus heated. Most preferably, functional groups X are also colorant groups.
Preferred functional groups X, performing all of these functions described in the previous paragraph, are residues of infrared absorbing dyes, preferably polymethine dyes, more preferably cyanine dyes. One definition of a cyanine dye, as disclosed in Hawley""s Condensed Chemical Dictionary (12th edition) (Van Nostrand Reinhold 1993), is a dye consisting of two heterocyclic groups connected by a chain of conjugated double bonds containing an odd number of carbon atoms. The definition includes isocyanines, merocyanines, cryptocyanines, phthalocyanines and dicyanines.
The several dissolution inhibition means described herein are not mutually exclusive. One example of a polymer which has two distinct dissolution inhibition means is a polymer having functional groups X as described above and diazide groups.
Preferably, the corresponding polymer without any pendent groups (referred to herein as the xe2x80x9cparent polymerxe2x80x9d) dissolves in the developer liquid. Thus, the colorant-tagged polymer is preferably insolubilized by means of functional groups thereon.
In preferred embodiments the colorant-tagged polymer on its own has the property that it does not dissolve in the developer liquid but does dissolve once heated. In other embodiments the colorant-tagged polymer on its own may or may not have this property to any useful degree, but a free compound is present in the composition, and confers this property on the composition, or supplements it, by inhibiting the dissolution of the polymer in the developer liquid. Such a compound is hereinafter called a xe2x80x9creversible insolubilizer compoundxe2x80x9d Without wishing to be bound by any one theory, it is believed that a complex forms between such a compound and the colorant-tagged polymer, the complex being disturbed by heat.
A useful class of reversible insolubilizer compounds are carbonyl functional group containing compounds.
Examples of suitable carbonyl containing compounds are naphthoflavone, 2,3-diphenyl-1-indeneone, flavone, flavanone, xanthone, bezophenone, N-(4-(bromobutyl)phthalimde and phenanthenequinone.
A reversible insolubilizer compound may be a compound of general formula:
Q1xe2x80x94S(O)qxe2x80x94Q2
where Q1 represents an optionally substituted phenyl or alkyl group, q represents 0, 1 or 2, and Q2 represents a halogen atom or any alkoxy group. Preferably Q1 represents a C1-4 alkyl phenyl group, for example a tolyl group, or a C1-4 alkyl group. Preferably q represents 1 or, especially, 2. Preferably Q2 represents a chlorine atom or a C1-4 alkoxy group, especially an ethoxy group.
Other useful reversible insolubilizer compounds are ferrocenium compounds, such as ferrocenium hexafluorophosphate.
Alternatively or additionally diazide group-containing compounds, admixed with the colorant-tagged polymer, may be employed.
Suitably, when present as a separate compound, the reversible insolubilizer compound constitutes at least 0.25%, preferably at least 0.5%, more preferably at least 1%, most preferably at least 2% of the total weight of the composition.
Preferably, when present as a separate compound, the reversible insolubilizer compound constitutes up to 25%, more preferably up to 15% of the total weight of the composition.
Thus a preferred weight range for the reversible insolubilizer compound may be expressed as 2-15% of the total weight of the composition.
In yet other embodiments a cover layer is provided, which acts as a physical barrier preventing the colorant-tagged polymer from contact with the developer liquid. On exposure to infra-red radiation the heat generated by the colorant-tagged polymer acts on the cover layer, which no longer acts as a barrier, but allows the developer liquid to contact the underlying colorant-tagged polymer, in the heated areas.
The colorant-tagged polymer may comprise pendent groups which act as colorant groups, infra-red absorbing groups and reversible insolubilizer groups. There may be one type of pendent group which performs all three of the functions described above. Alternatively the colorant-tagged polymer may comprise pendent groups which perform two of the functions described above, and different pendent groups on the same polymer which perform the third function.
In another embodiment the colorant-tagged polymer may comprise three different types of pendent group, each of which perform one of the functions selected from colorant, infra-red absorber and reversible insolubilizer.
The composition useful in the invention may further comprise a pigment.
Pigments as defined herein are insoluble in the compositions and so comprise colorant particles therein, and in the dried coatings. Generally they are broad band absorbers, preferably able efficiently to absorb electromagnetic radiation and convert it to heat over a range of wavelengths exceeding 200 nm, preferably exceeding 400 nm. Generally they are not decomposed by the radiation. Generally they have no or insignificant effect on the solubility of the unheated coatings in the developer. However some pigments may dissolve or break down in a developer and such pigments are within the ambit of the present invention provided that they do not thereby produce a colored solution which would cause staining.
Suitably the pigment constitutes at least 0.25%, preferably at least 0.5%, more preferably at least 1%, and most preferably at least 2%, of the total weight of the coating.
Suitably the pigment constitutes up to 25%, preferably up to 20%, and most preferably up to 15%, of the total weight of the coating.
References herein to the proportion of pigment are to their total content, when more than one pigment is employed.
Preferably the pigment is a material which can absorb infra-red radiation and convert it to heat. Examples include carbon pigments (for example the grades available as carbon black, lamp black, furnace black and channel black), black iron (III) oxide, manganese oxide, Milori Blue (C.I. Pigment Blue 27) available from Aldrich, Paris Blue available from Kremer, Prussian Blue, Heliogen Green available from BASF and Nigrosine Base NG1 available from NH Laboratories. However pigments which are not infra-red absorbers may be used for their colorant property. An example is copper phthalocyanine.
Preferably the composition contains a further polymeric component, being a polymer having hydroxyl groups as defined herein.
In accordance with a second aspect of the present invention there is provided a method of preparing a lithographic printing form precursor having an imagable coating on an aluminum support, the method comprising the steps of
(a) anodising an aluminum sheet (which is to serve as the support); and
(b) without having effected a chemical treatment step after the anodising step, applying a composition comprising a polymeric substance to the anodised surface of the aluminum sheet and drying the composition to form the imagable coating thereon, wherein the polymeric substance comprises pendent colorant groups, and wherein the composition does not contain a colorant dye.
In accordance with a third aspect of the invention there is provided a method of making a printing form from the printing form precursor of the second aspect, the method comprising the steps of:
(i) exposing the coating as described herein, imagewise; and
(ii) removing the exposed regions of the coating using a developer liquid.
Preferably in a method of the invention which uses a positive working coating, the coating is such that it is imagewise solubilized by heat.
In the specification when we state that a coating is developer soluble we mean that it is soluble in a developer, to an extent useful in a lithographic printing form development process. When we state that a coating is developer insoluble we mean that it is not soluble in a developer, to an extent useful in a lithographic printing form development process.
The developer composition is dependent on the nature of the components of the composition, but is preferably an aqueous composition. Common components of aqueous developers are surfactants, chelating agents such as salts or ethylenediamine tetraacetic acid, organic solvents such as benzyl alcohol, and alkaline components such as inorganic metasilicates, organic metasilicates, hydroxides or bicarbonates.
Preferably the aqueous developer is an alkaline developer containing inorganic or organic metasilicates when the polymeric substance, as is preferred, is a phenolic resin.
It has been found that by carrying out a suitable heat treatment in accordance with the invention of WO 99/21715, the contents of which are hereinafter incorporated by reference, the performance of the coating may be improved, in particular rendered more consistent over time. It is preferred to carry out such a heat treatment at a temperature of at least 40xc2x0 C., preferably at least 50xc2x0 C., most preferably at least 60xc2x0 C. As regards the upper limit, preferably the temperature is not in excess of 90xc2x0 C., more preferably not in excess of 80xc2x0 C., most preferably not in excess of 70xc2x0 C. Temperatures in the range 60-70xc2x0 C. are particularly preferred. Generally, the lower the temperature for the heat treatment, the longer the time should be. It is preferred to carry out the heat treatment for at least 4 hours; and more preferably for at least 24 hours and most preferably for at least 48 hours.
Preferably the sensitivity of the preferred coating of the precursors produced by the method of the invention is at a practicable level; suitably no more than 400 mJcmxe2x88x922, preferably no more than 250 mJcmxe2x88x922. A heat treatment as discussed above may be of assistance in achieving this.
Suitably the composition contains a developer resistance means as defined in WO 99/21725, suitably a siloxane, preferably constituting 0.1-10 wt %, more preferably 1-10 wt % of the composition. Preferred siloxanes are substituted by one or more optionally-substituted alkyl or phenyl groups, and most preferably are phenylalkylsiloxanes and dialkylsiloxanes. Preferred siloxanes have between 10 and 100 xe2x80x94Si(R1)(R2)Oxe2x80x94 repeat units. The siloxanes may be copolymerised with ethylene oxide and/or propylene oxide. For further information on preferred siloxanes the definitions in WO 99/21725 may be recited.
In certain embodiments of the invention heat is imagewise delivered conductively to the coating, by direct application. For example the coating may be contacted by a heat stylus; or the reverse face of the support surface bearing the coating may be contacted by a heat stylus.
In other embodiments of the invention electromagnetic radiation is preferably used to image the coating, the wavelength thereof preferably entirely or predominantly exceeding 500 nm. Preferably, it is of wavelength entirely or predominantly exceeding 600 nm. More preferably it is of wavelength entirely or predominantly exceeding 700 nm. Most preferably it is of wavelength entirely or predominantly exceeding 800 nm. Suitably it is of wavelength entirely or predominantly below 1400 nm. More preferably it is of wavelength entirely or predominantly below 1200 nm. Most preferably it is of wavelength entirely or predominantly below 1100 nm. Thus, suitably it is of wavelength entirely or predominantly in the range 600 to 1400 nm, more preferably 700 to 1200 nm, most preferably 800 to 1100 nm. The electromagnetic radiation is converted to heat by the pigment. Electromagnetic radiation is preferably delivered by a laser under digital control.
The precursors of the invention may be imaged with a laser or an array of lasers emitting infrared radiation in a wavelength region that closely matches the absorption spectrum of the infrared absorbing polymer. Suitable commercially available imaging devices include image setters such as a Creo Trendsetter (available from the Creo Corporation, British Columbia, Canada) and a Gerber Crescent 42T (available from the Gerber Corporation). Alternatively, the precursors of this invention may be imaged using an apparatus containing a thermal printing head or any other means for imagewise conductively heating the composite layer such as with a heated stylus.
The composition described herein may additionally contain other ingredients such as polymeric particles, stabilizing additives and additional inert polymeric binders as are well known to be present in many positive working compositions.
In accordance with a fourth aspect there is provided such a printing form, per se.
Preferably the printing form of the fourth aspect is used in a printing process without having undergone a post-development baking step. A post-development baking step can be carried out to obtain a substantial increase in run length achievable with a given printing form. However many customers do not want to, or cannot, subject their imaged and developed printing forms to a baking step but prefer instead to purchase precursors which can be used straight after development, that is, precursors which offer run lengths which are adequate without a post-development baking step.
In accordance with a fifth aspect of the present invention there is provided the use of a polymeric substance comprising pendent colorant groups as an additive in an imagable composition, to prevent the need for post anodic treatment of an anodized aluminum support coated with an imagable composition comprising said polymeric substance.