Acidic, hard surface cleaning and disinfecting compositions include a film-forming, organosilicone quaternary ammonium compound providing a protective layer for water and stain repellency

The invention relates to hard surface cleaning and disinfecting compositions providing a protective layer for water and stain repellency.
Cleaning compositions are commercially important products and enjoy a wide field of utility in assisting in the removal of dirt and grime from surfaces, especially those characterized as useful with xe2x80x9chard surfacesxe2x80x9d. Hard surfaces are those which are frequently encountered in lavatories such as toilets, shower stalls, bathtubs, bidets, sinks, etc., as well as countertops, walls, floors, etc. In such lavatory environment various forms of undesirable residues are known to form including hard water stains as well as xe2x80x9csoap scum stainsxe2x80x9d. Hard water stains are mineral stains caused by the deposition of salts, such as calcium or magnesium salts, frequently present in hard water. Soap scum stains are residues of fatty acid soaps such as those which are based on alkali salts of low fatty acids, which precipitate in hard water due to the presence of metal salts therein, leaving an undesirable residue upon such surfaces.
The prior art has suggested many compositions which are directed to the cleaning of such hard water and soap scum stains. (xe2x80x9cSoap scumxe2x80x9d is sometimes referred to as xe2x80x9climescalexe2x80x9d in Europe.) Many of these are acidic, aqueous compositions which include one or more detersive surfactants. A limited number of these compositions, in addition to a detersive benefit, also provide a germicidal or sanitizing effect to the hard surfaces being treated. Many of these prior art compositions also suffer from the shortcoming in that they do not provide any significant long term cleaning or sanitizing benefit to the treated hard surfaces as they are easily rinsed away with water, and thus are not retained on the treated hard surface. It would be desirable to provide a hard surface cleaning and/or disinfecting composition which is effective in the removal of hard water stains and/or soap scum stains from hard surfaces, which also provides a long term cleaning or sanitizing benefit. While such a formulation would be desirable to the art, such is not easy to produce. While it is known that polymers and film forming materials can be utilized to give a hard surface a protective layer, (i.e., acrylates, urethanes and silanes,) such materials are usually not compatible with chelating agents, quaternary ammonium salts, or in non-neutral pH conditions (i.e., acidic) that are known to be advantageous for cleaning and disinfecting of hard surfaces.
Accordingly there is a real and continuing need in the art for improved hard surface treatment compositions which provide a cleaning or disinfecting benefit, (preferably both) and which form a film on the treated surface to provides a residual protective benefit.
It is therefore among the objects of the invention to provide an aqueous acidic hard surface treatment composition which provides a cleaning benefit (particularly useful against hard water stains or soap scum, desirably both) or a disinfecting benefit which also forms film or surface coating on the treated hard surfaces, but which most desirably provides both a cleaning and disinfecting benefit. This film or surface coating provides the benefit of water or stain repellency to the treated hard surface, or provides the benefit of residual disinfection to the treated hard surface, but preferably provides both benefits.
It is yet a further object of the invention to provide a readily pourable and readily pumpable cleaning composition which features the benefits described above.
It is a further object of the invention to provide a process for cleaning or sanitization of hard surfaces, which process comprises the steps of providing the composition as outlined above, and applying an effective amount to a hard surface.
These and other objects of the invention will be more apparent from a reading of the specification and of the claims attached.
According to a first aspect of the invention there is provided an aqueous, acidic hard surface cleaning composition which provides a cleaning benefit or disinfecting benefit (preferably both benefits) to a hard surface which comprises the following constituents:
(a) a film-forming, organosilicone quaternary ammonium compound;
(b) at least one zwitterionic surfactant compound which is compatible with the quaternary ammonium compound, preferably including at least one amine oxide compound;
(c) at least one nonionic surfactant;
(d) at least one organic solvent; and,
(e) optionally, at least one amphoteric surfactant;
(f) water.
wherein the aqueous compositions are at an acidic pH, preferably are at a pH of 4 or less, (preferably at a pH of 3 or less, even more preferably at a pH of 2 or less) and wherein the aqueous compositions may be characterized as forming a film or surface coating which provides the benefit of water or stain repellency to the treated hard surface, or provides the benefit of residual disinfection to the treated hard surface, but preferably provides both benefits.
The compositions described above may include one or more further optional constituents including but not limited to further non-aqueous (organic) solvents, pH buffering agents, perfumes, perfume carriers, colorants, hydrotropes, germicides, thickeners, fungicides, anti-oxidants, anti-corrosion agents, etc.
Preferred compositions according to the invention are largely aqueous, comprising at least 80% wt. water, and are readily pourable and pumpable. The preferred compositions all exhibit good storage stability.
According to a second aspect of the invention, there is provided a process for cleaning or sanitization of hard surfaces, which process comprises the step of providing the composition as outlined above, and applying an effective amount to a hard surface requiring such treatment.
The compositions of the present invention provide excellent cleaning efficacy on hard water stains or soap scum on hard surfaces, as well as providing water repellency, and soap scum and hard water stain removal benefits. At the same time, the preferred compositions of the present invention also provide disinfecting efficacy to hard surfaces, while imparting a film or surface coating to the hard surface, which acts as a barrier to repel water and facilitate the reduction or prevention of further hard water stains or soap scum on said hard surfaces.
The acidic, aqueous compositions according to the invention comprise (a) a film-forming, organosilicone quaternary ammonium compound. Such compounds desirably also exhibit antimicrobial activity, especially on hard surfaces.
Specific examples of organosilicone quaternary ammonium salts that may be used in the compositions of this invention include organosilicone derivatives of the following ammonium salts: di-isobutylcresoxyethoxyethyl dimethyl benzyl ammonium chloride, di-isobutylphenoxyethoxyethyl dimethyl benzyl ammonium chloride, myristyl dimethylbenzyl ammonium chloride, myristyl picolinium chloride, N-ethyl morpholinium chloride, laurylisoquinolinium bromide, alkyl imidazolinium chloride, benzalkonium chloride, cetyl pyridinium chloride, coconut dimethyl benzyl ammonium chloride, stearyl dimethyl benzyl ammonium chloride, alkyl dimethyl benzyl ammonium chloride, alkyl diethyl benzyl ammonium chloride, alkyl dimethyl benzyl ammonium bromide, di-isobutyl phenoxyethoxyethyl trimethyl ammonium chloride, di-isobutylphenoxyethoxyethyl dimethyl alkyl ammonium chloride, methyl-dodecylbenzyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide, octadecyl dimethyl ethyl ammonium bromide, cetyl dimethyl ethyl ammonium bromide, octadec-9-enyl dimethyl ethyl ammonium bromide, dioctyl dimethyl ammonium chloride, dodecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, octadecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium iodide, octyl trimethyl ammonium fluoride, and mixtures thereof. Other water dispersible salts, such as the acetates, sulfates, nitrates and phosphates, are effective in place of the halides, but the chlorides and bromides are preferred. The silicone group is preferably substituted with alkyl ethers. Preferred alkyl ethers are short carbon chain ethers such as methoxy and ethoxy substituents.
Examples of particularly preferred film-forming, organosilicone quaternary ammonium compounds which find use in the present inventive compositions include those which may be represented by the following structural representation:
wherein:
R1 and R2 each independently represents short chain alkyl or alkenyl groups, preferably C1-C8 alkyl or alkenyl groups;
R3 represents a C11-C22 alkyl group; and
X represents a salt forming counterion, especially a halogen.
Preferred short chain alkyl substituents for R1 are methyl and ethyl. Preferred short chain alkyl substituents for R2 are straight chain links of methylene groups consisting of from 1 to 4 members. Preferred R3 substituents are straight chain links of methylene groups consisting of from 11 to 22 members, and preferred halogens for X are chloride and bromide. More preferably, both R1 and R2 are methyl.
A particularly preferred and commercially available film-forming, organosilicone quaternary ammonium compound useful in the inventive compositions is AEM(copyright) 5772 or AEM(copyright) 5700 (from Aegis Environmental Co., Midland, Mich.). Both of these materials are described as being 3-(trimethoxysilyl)propyloctadecyldimethylammonium chloride, AEM(copyright) 5700 and is sold as a 42% by weight active solution of the compound in a water/methanol mixture, while AEM(copyright) 5772 is sold as a 72% by weight active solution of the compound in a water/methanol mixture.
The film-forming, organosilicone quaternary ammonium compound are desirably present in the inventive compositions in amounts of from 0.01 to 1.0% by weight, preferably in amounts of from 0.05 to 0.9% wt., and most preferably from 0.1 to 0.7% by weight, based on the total weight of the aqueous composition of which it forms a part.
The compositions of the invention also contain (b) at least one zwitterionic surfactant compound, which is compatible with the (a) film-forming, organosilicone quaternary ammonium compound. This zwitterionic surfactant is most preferably an amine oxide compound. Useful amine oxides, may be defined as one or more of the following of the four general classes:
(1) Alkyl di (lower alkyl) amine oxides in which the alkyl group has about 6-24, and preferably 8-18, carbon atoms and can be straight or branched chain, saturated or unsaturated. The lower alkyl groups include from 1 to 7 carbon atoms, but preferably each include 1-3 carbon atoms. Examples include octyldimethylamine oxide, lauryldimethylamine oxide, myristyldimethylamine oxide, and those in which the alkyl group is a mixture of different amine oxides, such as dimethylcocoamineoxide, dimethyl(hydrogenated tallow)amine oxide, and myristyl/palmityldimethyl amine oxide;
(2) Alkyl di (hydroxy lower alkyl) amine oxides in which the alkyl group has about 6-22, and preferably 8-18, carbon atoms and can be straight or branched chain, saturated or unsaturated. Examples include bis-(2-hydroxyethyl)cocoamine oxide, bis-(2-hydroxyethyl)tallowamine oxide; and bis-(2-hydroxyethyl)stearylamine oxide;
(3) Alkylamidopropyl di(lower alkyl) amine oxides in which the alkyl group has about 10-20, and preferably 12-16, carbon atoms and can be straight or branched chain, saturated or unsaturated. Examples are cocoamidopropyldimethylamine oxide and tallowamidopropyldimethylamine oxide; and
(4) Alkylmorpholine oxides in which the alkyl group has about 10-20, and preferably 12-16, carbon atoms and can be straight or branched chain, saturated or unsaturated.
The preferred amine oxides are those which may be represented by the structure:
wherein
each R1 independently is a straight chained C1-C4 alkyl group, preferably both R1 are methyl groups; and
R2 is a straight chained C6-C22 alkyl group, preferably a C6-C16 alkyl group, and most preferably is a C8-10 alkyl group, especially a C8 alkyl group;
Each of the alkyl groups may be linear or branched, but preferably are linear. Most preferably the amine oxide constituent is lauryldimethylamine oxide. Technical grade mixtures of two or more amine oxides may be used, wherein amine oxides of varying chain lengths of the R2 group. Preferably, the amine oxides used in the present invention include R2 groups which comprise at least 50% wt., preferably at least 75% wt., of C8 alkyl group.
Exemplary and preferred amine oxide compounds include N-alkyldimethylamine oxides, particularly octyldimethylamine oxides as well as lauryldimethylamine oxide. These amine oxide compounds are available as surfactants from McIntyre Group Ltd. under the name Mackamine(copyright) C-8 which is described as a 40% by weight active solution of octyldimethylamine oxide, as well as from Stepan Co., under the trade name Ammonyx(copyright) LO which is described to be as a 30% wt. active solution of lauryldimethylamine oxide.
The compositions of the present invention contain from 0.05 to 5% by weight of the zwitterionic amine oxide compound. Desirably the amine oxide compound is present on amounts of from 0.1 to 2.5% wt., more desirably form from 0.5 to 2.0% wt. of the present inventive compositions.
The compositions of the present invention further include (c) a nonionic surfactant. Suitable nonionic surfactants include, inter alia, condensation products of alkylene oxide groups with an organic hydrophobic compound, such as an aliphatic compound or with an alkyl aromatic compound. The nonionic synthetic organic detergents generally are the condensation products of an organic aliphatic or alkyl aromatic hydrophobic compound and hydrophilic ethylene oxide groups. Practically any hydrophobic compound having a carboxy, hydroxy, amido, or amino group with a free hydrogen attached to the nitrogen can be condensed with ethylene oxide or with the polyhydration product thereof, polyethylene glycol, to form a water soluble nonionic detergent. Further, the length of the polyethenoxy hydrophobic and hydrophilic elements may be varied to adjust these properties.
One example of such a nonionic surfactant is the condensation product of one mole of an alkylphenol having an alkyl group containing from 6 to 12 carbon atoms with from about 5 to 25 moles of an alkylene oxide. Another example of such a nonionic surfactant is the condensation product of one mole of an aliphatic alcohol which may be a primary, secondary or tertiary alcohol having from 6 to 18 carbon atoms with from 1 to about 10 moles of alkylene oxide. Preferred alkylene oxides are ethylene oxides or propylene oxides or mixtures thereof.
Preferred nonionic surfactants include primary and secondary linear and branched alcohol ethoxylates, such as those based on C10 to C16 alcohols which further include an average of from 3 to 10 moles of ethoxylation per mol of alcohol Particularly preferred nonionic surfactants are C11 linear primary alcohol ethoxylates averaging about 9 moles of ethylene oxide per mole of alcohol. These surfactants are available, for example, under the commercial name of Neodol 1-9, (from Shell Chemical Company, Houston, Tex.), or in the Genapol(copyright) series of linear alcohol ethoxylates, particularly Genapol(copyright) 26-L-60 or Genapol(copyright) 26-L-80 (from Clariant Corp., Charlotte, N.C.). A further class of nonionic surfactants which are advantageously present in the inventive compositions are those presently marketed under the Genapol(copyright) trade name. Particularly useful are those in the Genapol(copyright) xe2x80x9c26-Lxe2x80x9d series which include for example: C12-16 linear alcohols condensed with 1 mole of ethylene oxide (Genapol(copyright) 24-L-3); C12-16 linear alcohols condensed with 1.6 moles of ethylene oxide (Genapol(copyright) 26-L-1.6); C12-16 linear alcohols condensed with 2 moles of ethylene oxide (Genapol(copyright) 26-L-2); C12-16 linear alcohols condensed with 3 moles of ethylene oxide (Genapol(copyright) 26-L-3); C12-16 linear alcohols condensed with 5 moles of ethylene oxide (Genapol(copyright) 26-L-5); as well as C12-16 linear alcohols condensed with varying amounts of ethylene oxide to provide specific cloud points of the surfactant (i.e., Genapol(copyright) 26-L-60, Genapol(copyright) 26-L-60N, and Genapol(copyright) 26-L-98These materials are commercially available Clariant Corp. (Charlotte, N.C.).
It is to be understood that nonionic surfactants other than those described above may also be used. By way of illustration, and not by way of limitation, examples include secondary C12 to C15 alcohol ethoxylates, including those which have from about 3 to about 10 moles of ethoxylation. Such are available in the Tergitol(copyright) series of nonionic surfactants (Union Carbide Corp., Danbury, Conn.), particularly those in the Tergitol(copyright) xe2x80x9c15-S-xe2x80x9d series. Further exemplary nonionic surfactants include linear primary C11 to C15 alcohol ethoxylates, including those which have from about 3 to about 10 moles of ethoxylation. Such are available in the Neodol(copyright) series of nonionic surfactants (Shell Chemical Co.)
The compositions of the invention contain from 0.05 to 1.5% by weight of a nonionic surfactant, based on the weight of the surfactant as a whole. Preferably, the compositions contain from 0.1 to 1.0% by weight of a nonionic surfactant. Most preferably, the compositions contain from 0.15 to 0.75% by weight of a nonionic surfactant, based on the weight of the compositions as a whole.
The compositions of the invention also comprise (d) an organic solvent constituent. Preferred organic solvents are those which show some solubility in water. Included among these are substituted hydrocarbons, especially those substituted with oxygen or nitrogen. Preferred classes of solvents with these characteristics are alcohols, amines, amides, esters and ethers.
Useful organic solvents are those which are at least partially water-miscible such as alcohols, water-miscible ethers (e.g. diethylene glycol diethylether, diethylene glycol dimethylether, propylene glycol dimethylether), water-miscible glycol ether (e.g. propylene glycol monomethylether, propylene glycol monoethylether, propylene glycol monopropylether, propylene glycol monobutylether, ethylene glycol monobutylether, dipropylene glycol monomethylether, diethyleneglycol monobutylether), lower esters of monoalkylethers of ethylene glycol or propylene glycol (e.g. propylene glycol monomethyl ether acetate) which are commercially available from various sources including: Union Carbide (Danbury, Conn.), Dow Chemical Co.(Midland, Mich.), and Eastman Chemical Co. (Kingsport, Tenn.). Mixtures of one or more of these organic solvents can also be used.
Preferred as solvents in this invention are the glycol ethers having the general structure Raxe2x80x94Oxe2x80x94Rbxe2x80x94OH, wherein Ra is an alkoxy of 1 to 20 carbon atoms, or aryloxy of at least 6 carbon atoms, and Rb is an ether condensate of propylene glycol and/or ethylene glycol having from 1 to 10 glycol monomer units. Preferred are glycol ethers having 1 to 5 glycol monomer units. These are C3-C20 glycol ethers. Examples of more preferred solvents include propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol isobutyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, diethylene glycol phenyl ether, propylene glycol phenyl ether, and mixtures thereof. These materials include those available in the DOWANOL(trademark) glycol ether series (Dow Chemical Co., Midland Mich.), or the CARBITOL(trademark) series (Union Carbide Corp.) or the ARCOSOLV(copyright) series (ARCO Chemical Corp.). More preferably employed as the solvent is one or more solvents of the group consisting of: propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-propyl ether, ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, and mixtures thereof. Most preferably, the solvent is a diethylene glycol n-butyl ether [also recognized by the names 2-(2-butoxyethoxy)ethanol, butoxydiglycol and diethylene glycol monobutyl ether] having the formula: C4H9OCH2CH2OCH2CH2OH, and is available, for example, in the DOWANOL(trademark) glycol ether series as DOWANOL DB diethylene glycol n-butyl ether.
The compositions of the invention contain from 0.1 to 10% by weight of the organic solvent, based on the total weight of the inventive compositions. Preferably, the organic solvent constituent is present from 1 to 8% by weight, more preferably from 2 to 7% by weight.
Optionally, but in certain cases desirably, the inventive compositions include (e) at least one amphoteric surfactant. By way of example, these include the salts of higher alkyl beta-amino propionic acids, e.g., sodium N-lauryl beta-alanine; the higher alkyl substituted betaines, such as lauryl dimethylammonium acetic acid; as well as amphoteric surfactants of the the imidazoline type exemplified by the disodium salt of 1-(2-hydroxyethyl)-1-(carboxymethyl)-2-(hendecyl)-4,5-dihydroimidazolinium hydroxide. An exemplary an preferred amphoteric surfactant is lauramidopropionic acid, which is commerically available in the DERIPHAT series (ex Henkel) or MACKAM series (ex McIntyre Group Inc.) of amphoteric surfactants. When present, they may comprise up to 5% wt. of the inventive compositions.
The compositions are largely aqueous in nature, and comprise as a further necessary constituent (f) water. Water is added to order to provide to 100% by weight of the compositions of the invention. The water may be tap water, but is preferably distilled and is more preferably deionized water. If the water is tap water, it is preferably substantially free of any undesirable impurities such as organics or inorganics, especially minerals salts which are present in hard water which may undesirably interfere with the operation of the constituents present in the aqueous compositions according to the invention.
As discussed previously, the inventive compositions may comprise one or more conventional optional additives. By way of non-limiting example, these include: pH adjusting agents and pH buffers including organic and inorganic salts; non-aqueous solvents; perfumes and perfume carriers; optical brighteners; coloring agents such as dyes and pigments; opacifying agents; hydrotropes; antifoaming agents; viscosity modifying agents such as thickeners; enzymes; anti-spotting agents; anti-oxidants; and anti-corrosion agents. These ingredients may be present in any combination and in any suitable amount that is sufficient for imparting the desired properties to the compositions, but it is to be understood that, in accordance with preferred embodiments of the invention, the inventive compositions are essentially free of conventional chelating agents. These one or more conventional optional additives, when present, should be present in minor amounts, preferably in total comprising less than about 5% by weight of the compositions, and desirably less than about 3% wt.
The compositions of the invention show improved efficacy at low pH values. Therefore it is desirable that the compositions of the invention have pH values that are acidic. The pH value of the aqueous composition is 4 or less, desirably is 3 or less, more desirably in the range of from 0.1 to 2, and particularly from 0.5-1.2. Such acidic pH values may be achieved by the use of one or more pH-adjusting constituents. Such acidic pH-adjusting constituents include for example, one or more organic acids (i.e., glycolic acid, sulfamic acid, citric acid or salts thereof). Preferably, the pH-adjusting constituents are chosen from glycolic acid, citric acid and mixtures of these two acids. The acidic pH-adjusting constituent is desirably present in the compositions of the invention from about 1 to 20% by weight, based on the weight of the composition as a whole. Preferably, the compositions contain from 3 to 15% by weight of an acidic pH-adjusting constituent. Most preferably, the compositions contain from 6 to 12% by weight of an acidic pH-adjusting agent, based on the weight of the pH-adjusting agent as a whole.
Such materials described herein are known to the art, including those described in McCutcheon""s Emulsifiers and Detergents (Vol. 1), McCutcheon""s Functional Materials (Vol. 2), North American Edition, 1991; Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd Ed., Vol. 22, the contents of which are herein incorporated by reference For any particular composition, such optional ingredients should be compatible with the other ingredients present.
According to a particularly preferred embodiment of the invention there is provides an aqueous, acidic hard surface cleaning composition which provides a cleaning benefit or disinfecting benefit (preferably both benefits) to a hard surface which comprises, but preferably consists essentially of, the following constituents:
a) 0.01 to 1.0% wt. of a film-forming, organosilicone quaternary ammonium compound;
b) 0.05 to 5% wt. of at least one zwitterionic surfactant which is compatible with the quaternary ammonium compound;
c) 0.05 to 1.5% wt. of at least one nonionic surfactant;
d) 0.1 to 1 0% wt. of at least one organic solvent;
e) 0-5% wt. of at least one amphoteric surfactant, preferably a salt of a higher alkyl beta-amino propionic acid;
f) 80-100% wt. water; and,
g) 0-5% wt. of one or more optional constituents;
wherein the aqueous compositions are at an acidic pH, preferably are at a pH of 4 or less, more preferably a pH of 3 or less, and wherein the aqueous compositions may be characterized as forming a film or surface coating which provides the benefit of water or stain repellency to the treated hard surface, or provides the benefit of residual disinfection to the treated hard surface, but preferably provides both benefits.
The aqueous compositions according to the invention are desirably provided as a ready to use product which may be directly applied to a hard surface. Hard surfaces which are to be particularly denoted are lavatory fixtures and lavatory appliances (toilets, bidets, shower stalls, bathtubs and bathing appliances), wall and flooring surfaces especially those which include refractory materials and the like. Further hard surfaces which are particularly denoted are those associated with kitchen environments and other environments associated with food preparation. Hard surfaces also include those associated with hospital environments, medical laboratories and medical treatment environments. Such hard surfaces described above are to be understood as being recited by way of illustration and not by way of limitation.
The aqueous compositions according to the invention are particularly useful in the treatment of hard surfaces wherein hard water stains or soap scum are prone to occur, particularly hard surfaces associated with lavatories including lavatory fixtures and appliances.
The composition provided according to the invention can be desirably provided as a ready to use product in a manually operated spray dispensing container.
The composition according to the invention is ideally suited for use in a consumer xe2x80x9cspray and wipexe2x80x9d application. In such an application, the consumer generally applies an effective amount of the cleaning composition using a pump and within a few moments thereafter, wipes off the treated area with a rag, towel, or sponge, usually a disposable paper towel or sponge. In certain applications, however, especially where undesirable stain deposits are heavy, the cleaning composition according to the invention may be left on the stained area until it has effectively loosened the stain deposits after which it may then be wiped off, rinsed off, or otherwise removed. For particularly heavy deposits of such undesired stains, multiple applications may also be used. It is also to be understood that longer residence time of the inventive compositions on a hard surface may be required in order to attain greater degrees of cleaning, sanitization or disinfection. Where thorough disinfection is a primary consideration, it may be desired to apply the inventive compositions to the hard surface being treated and to permit the composition to remain on the hard surface for several minutes (2-10 min.) prior to rinsing or wiping the composition from the hard surface. It is also contemplated that the inventive compositions be applied to a hard surface without subsequently wiping or rinsing the treated hard surface.
Whereas the compositions of the present invention are intended to be used in the types of liquid forms described above, nothing in this specification shall be understood as to limit the use of said compositions with a further amount of water to form a cleaning solution. In such a proposed diluted cleaning solution, the greater the proportion of water added to form said cleaning dilution will, the greater may be the reduction of the rate and/or efficacy of the inventive compositions. Accordingly, longer residence times upon the surface and/or the usage of greater amounts may be necessitated. Conversely, nothing in the specification shall be also understood to limit the forming of a xe2x80x9csuper-concentratedxe2x80x9d cleaning composition based upon the composition described above. Such super-concentrated ingredient compositions are essentially the same as the cleaning compositions described above except in that they include a lesser amount of water.
The following examples below illustrate exemplary and preferred formulations of the composition according to the instant invention. It is to be understood that these examples are presented by means of illustration only and that further useful formulations fall within the scope of this invention and the claims may be readily produced by one skilled in the art without deviating from the scope and spirit of the invention.
Throughout this specification and in the accompanying claims, weight percents of any constituent are to be understood as the weight percent of the active portion of the referenced constituent, unless otherwise indicated.

Acidic hard surface cleaning and disinfecting compositions which include silicone quarternary ammonium salts


It is to provide a process for preparing a conductive material in which transparency and conductivity are both high, and storage stability is high, and further, in a process for preparing a conductive material utilizing ultra fine silver particles, to provide a process for preparing a conductive material having high conductivity without requiring a calcination step which has conventionally been required.

In recent years, accompanying with rapid progress of an information-oriented society, techniques regarding information-related apparatuses have rapidly been progressed and spread. Of these, a display device has been used for television, for a personal computer, for an information display at a station, airport, etc., and for providing other various kinds of information. In particular, plasma display is attracted attention in recent years.
In such an information-oriented society, it has been worried about influence of an electromagnetic wave emitted by these display device. For example, it has been worried about influence on neighbouring electronic devices or influence on a human body. In particular, influence of an electromagnetic wave which exerts to health of a human body cannot ignore, and a strength of electromagnetic field emitted to the human body is required to be reduced. To comply with these demands, various transparent conductive materials to be used for an electromagnetic wave shielding material are developed, and there are disclosed in, for example, JP 9-53030A, JP 11-126024A, JP 2000-294980A, JP 2000-357414A, JP 2000-329934A, JP 2001-38843A, JP 2001-47549A, JP 2001-51610A, JP 2001-57110A, JP 200160416A, etc.
As processes for preparing these transparent conductive materials, there has generally been used a process in which a conductive metal such as silver, copper, nickel, indium, etc. is formed on a transparent resin film as a metal thin film by the method such as a sputtering method, ion plating method, ion beam assist method, vacuum deposition method, wet coating method, etc. However, according to these conventional methods, manufacturing processes become extremely complicated, so that they cause problems of high cost and poor productivity.
Also, as the other characteristics required to the transparent conductive material, there are conductivity and light transmittance. To heighten conductivity, it is necessary to prepare a metal thin film fine pattern having a width and thickness with a certain degree, but when a line width of a pattern comprising a metal which shields light is made thick, then a transmittance lowers. To comply with the both requirements simultaneously, it is necessary to prepare a fine metal pattern having sufficient conductivity, in particular, uniform pattern with a minimum width is required to be prepared, but this cannot be satisfied by the conventional methods.
For preparing a uniform pattern, in recent years, there has been proposed a method of using a silver salt light-sensitive photographic material containing a silver halide emulsion layer(s) as a precursor of the transparent conductive material. For example, in WO 01/51276A (Patent Literature 1) or JP 2004-221564A (Patent Literature 2), there have been proposed a process for preparing a transparent conductive material by pattern-wisely exposing a silver salt light-sensitive photographic material, subjecting to development, and then, subjecting to a metal plating treatment. As a method of using a silver salt light-sensitive material similarly, there has been proposed a method of using a silver salt diffusion transfer method, and there is, for example, JP 2003-77350A (Patent Literature 3), etc.
As a precursor for the conductive material, when a higher conductance is required in a conductive material using a silver salt light-sensitive photographic material, a metal plating treatment is carried out. However, when an electrolytic metal plating is to be applied to a particularly fine metal pattern, in the fine pattern, resistance of the pattern becomes too high for applying an electro-lytic plating to the fine pattern, whereby only a portion to which electricity is applied is occasionally plated. Accordingly, to carry out the electrolytic metal plating treatment uniformly, a process for preparing a conductive material, which gives high conductivity even in a fine metal pattern, has been required to be developed.
Moreover, in a conductive material using various kinds of silver salt light-sensitive photographic material as a precursor for the conductive material, conductivity is sometimes fluctuated during the preservation. As an example in which the above causes a problem, there is a ¼λ type electromagnetic absorber. In the ¼λ type electromagnetic absorber, it employs a structure in which a transparent resistance film which is equivalent to 377Ω/□ that is a characteristic impedance of a free space is provided at the position apart from ¼ of the wavelength λ of the electric wave absorbed from an electric wave reflecting material. In a conductive material using a silver salt light-sensitive photographic material as a precursor of the conductive material, a resistant material having high transparency can be prepared, but due to the problem of fluctuation of conductivity, the resistivity is deviated and the characteristics of the electromagnetic absorber is deteriorated during its preservation. As can be seen from this example, it has been required to provide a process for preparing a conductive material which has not only sufficiently high conductivity, but also high storage stability simultaneously.
The conductive material is further used in various fields such as shielding of infrared rays of construction materials or automobiles, antistatic materials for electronic devices or cell phones, heat rays of frosted glass, a wiring of circuit boards or IC cards, a coating for providing conductivity to resins, through hole, circuit itself, etc.
In particular, in preparation processes of a semiconductor device, liquid crystal display device, plasma display device, etc., a conductive metal thin film is sometimes to be formed to form an electrode or wiring, etc. In these preparation processes, the metal thin film is generally prepared by a thin film-forming method such as a vacuum deposition, sputtering, CVD method, etc. Such a thin film-forming method is generally carried out under an atmosphere of reduced pressure, so that a substrate, etc. is required to be provided in a reaction vessel such as a vacuum chamber, etc. Accordingly, an object to be formed by a metal thin film is larger, a vacuum chamber which can contain such a large sized object therein is necessary, whereby there is a problem that preparation of such a material is difficult.
Also, in the preparation of a flexible printed circuits, for forming a conductive part at a concave portion such as a contact hole or a via hole, etc., there is a case of using, for example, silver paste in which silver particles having a size of 1 μm or so are mixed and kneaded in a resin, but conductivity is ensured by contact of silver particles with each other, so that there is a problem that conductivity is low.
In JP 3-281783A (Patent Literature 4), there is disclosed a method in which paste having been dispersed metal ultra fine particles therein is coated, and after coating, this is sintered at a temperature of about 900° C. to form a metal thin film. According to this method, a metal thin film can be formed by coating paste, so that it is suitable for forming a metal thin film with a large area or forming a metal thin film on a support having a complicated surface shape.
Also, in JP 2001-35255A (Patent Literature 5), there is disclosed a ultra fine silver particles-independently dispersed liquid which comprises an organic solvent which evaporates at a drying-calcinating step for forming a silver wiring on a semiconductor substrate, and silver-containing ultra fine particles having a particle size of 0.01 μm or less being mixed, each surface of said ultra fine particles being covered by said organic solvent to be independently dispersed, a viscosity at room temperature being 50 mPa·s or lower. Thus, an extremely high conductivity can be obtained by calcinating the material at a temperature of 300° C. to give a silver thin film.
However, the metal colloid solution in which these metal ultra fine particles are dispersed in a liquid is prepared by evaporating a metal under reduced atmosphere, and monodispersibility is high, so that it is suitable for, for example, a nozzle type pattern forming device such as an ink-jet system, etc. However, for obtaining conductivity, a temperature of at least 200° C. is necessary, so that a usable substrate is limited to a heat-resistant support such as glass, polyimide, ceramic, etc.
On the other hand, it has been known a process for preparing metal ultra fine particles coated by a dispersant by reducing an aqueous silver nitrate solution, etc. with a reducing agent in the presence of a dispersant which is the so-called protective colloid.
For example, in American Journal of Science, Vol. 37, P476-491, 1889, M Carey Lea., there has been reported a method of obtaining a metal colloid solution which comprises citric acid or a salt thereof is added to an aqueous solution of a metal salt as a dispersant, a reducing agent such as a primary iron ion, etc. is then added to the same, and then, desalting and condensation are carried out. Also, in Experiments in Colloid Chemistry, 1940, p. 19, Hauser, E. A. and Lynn, J. E., there has been reported a method of obtaining a metal colloid solution using dextrin as a dispersant and as a reducing agent. However, even when a pattern formed by using these metal colloid solutions is sintered, a dispersant is difficultly evaporated so that the resulting conductivity was low.
Also, as metal ultra fine particles reduced in an aqueous solution and showing good conductivity, for example, there are disclosed, in JP 2002-338850A (Patent Literature 6), a metal colloid solution and a process for preparing the same which is prepared by using a polymerized material of a (thio)phenol derivatives) and to give a conductive film by calcinating under mild conditions. However, it was a metal colloid solution showing a high resistance value by calcinating at lower than 100° C. In JP 2005-081501A (Patent Literature 7), there are disclosed stable metal ultra fine particles and a process for pre-paring the same which can establish practically employable conductivity at a low temperature sintering. There is disclosed that practically employable conductivity can be established by calcination at 140 to 220° C., but the process yet requires the calcination step.
These metal ultra fine particles contained in the metal colloid solution are generally coated by a dispersant, so that in the state that a dispersing medium such as water, etc., has been evaporated by a drying step, connection between said metal ultra fine particles is not formed, whereby the resulting material does not show any conductivity, or extremely low even when it showed conductivity. Thus, to obtain good conductivity which can be used as a conductive material, it is necessary to carry out a calcination step to decompose and evaporate said dispersant, and to form mutual connection of said metal ultra fine particles due to fusion thereof, whereby not only an energy therefor is necessary but also a usable substrate is limited in the point of heat-resistance.
In order to develop conductivity without heating, or by low temperature heating, there has been carried out a device on a substrate. For example, in JP 2004-127851A (Patent Literature 8), there is disclosed a conductive film-complex material wherein a conductive film-complex material comprises laminated conductive films formed by drying metal colloid, and using an image receiving layer containing at least a porous inorganic filler, and in JP 2005-32458A (Patent Literature 9), there is disclosed a conductive film-complex material wherein the conductive film-complex material comprises laminated conductive films formed by drying a metal colloid solution on a substrate, and an intermediate layer comprising a water-soluble resin or hydrophilic resin and having a ten-point average surface roughness Rz according to JIS B 0601 is 3 μm or less is interposed between the conductive film and the substrate, and volume resistivity thereof is 10×10−5 Ω·cm or less.    Patent Literature 1: WO 01/51276    Patent Literature 2: JP 2004-221564A    Patent Literature 3: JP 2003-77350A    Patent Literature 4: JP 3-281783A    Patent Literature 5: JP 2001-35255A    Patent Literature 6: JP 2002-338850A    Patent Literature 7: JP 2005-081501A    Patent Literature 8: JP 2004-127851A    Patent Literature 9: JP 2005-32458A

Process for preparing conductive material

Abstract: A process for preparing a conductive material having a conductive pattern containing silver on a support, which process for preparing a conductive material comprises acting at least one of the following mentioned (I) to (IV) on the pattern portion containing silver provided on the support:

Abstract: (I) a reducing substance,

Abstract: (II) a water-soluble phosphorus oxo acid compound,

Abstract: (III) a water-soluble halogen compound,

Abstract: (IV) warm water of 55° C. or higher.


A vehicle and method of use in subsea operations related to crushing concrete mattresses including at least one lift assembly, at least one crushing roller, at least one blow out pipe cable of blowing crushed concrete mattress fragments into a rubble container. In a preferred embodiment, the vehicle has at least one fork lift connected to the lift assembly, a digger chain assembly arrangement, treads, an interface connected to the vehicle and capable of engaging the rubble container, and each rubble container is detachable from the interface.

Technical Field of Invention
The invention disclosed and taught herein relates generally to a system and method for use of a vehicle for use in environments such as but not limited to subsea environments.
Background of the Invention
Pipeline support and stabilization mattresses have been used in subsea operations. There have been various designs over the years. For example, some of the early designs used large canvas bags that included materials such as bituminous material mixed with aggregates. There were issues with these designs. For example, when these mattresses were left of the deck of a vessel, they were prone to softening and the heat from the engine rooms or exposure of sunlight could affect the shape of the mattresses. Once installed in subsea locations, the mattresses could become brittle, crack, and become stiff enough to not properly lay on the pipeline or spool they were installed over. This could lead to accidents related to moving or lifting the mattresses.
Subsequently, concrete mattresses were introduced. These concrete mattresses were referred to as link-lok mattresses. These mattresses were usually a sheet of premade plastic pots connected together by rope. The plastic pots contained cured concrete. This allowed for easier transportation of the pots to a remote location before the filling and the curing of the concrete in the pots. Unfortunately, this method proved to be expensive. Additionally, it became impractical to revert to the bituminous type mattresses due to new regulations.
Accordingly, a new method was introduced that installed and positioned mold produced concrete mattresses with either installation frame, beam, or speedloader frames. In this configuration, mattresses have to be installed and repositioned individually. This is advantageous because the frame can carry three to five mattresses. Moreover, this method requires a diver and a remotely operable vehicle ("ROV") to deploy the mattresses.
These methods include recovery by frame or beam. In this method, mattresses are either recovered to the surface one at a time using either the lifting beam or frame wherein the rigging is connected either by divers or ROV intervention. Alternatively, a small number of concrete mattresses are loaded onto speedloaders at the seafloor and then lifted to the surface for re-use or disposal.
Another method is recovery by subsea modified skip or half-height. In this method, the mattresses must be individually rigged by diver or ROV at the seafloor using the frame/beam method described above, then lifted and placed into a modified half height container, which in turn must then be lifted to the surface via surface vessel or platform deck crane.
Another method is recovery by steel wire rope nets or custom flat-racks. This method is a variation/alternative to the speedloader method described above, where by a number of mattresses are loaded subsea one at a time onto either out-spread steel cargo nets or flat-racks using the diver or ROV rigged frame/beam method and then the nets/flat racks are lifted to the surface via the vessel/platform deck crane.
Another method is recovery by hydraulic grapple connected to vessel/platform deck crane. In this method, mattresses are lifted individually by large hydraulic grapple, subsea which partially crushes the mattress structure and the load is recovered to the vessel/platform deck.
There are issues with each of these methods. For example, recovery of mattresses through the splash zone using the integral polypropylene rope loops are not recommended due to concerns regarding the integrity of the loops prior to attempting the lift.
Similarly any method which relies on the interaction of divers to complete the mattress lifting or positioning activity, including guiding and orientating the suspended mattresses in the half heights subsea, may be considered as a high risk activity.
Moreover, when subsea half heights/containers are used, the total lift loads may be difficult to establish and there also may be high seabed suction loads. The method is also difficult for high volumes of mattress recovery because of the number of containers required and the amount of space required on the vessel deck.
Furthermore, the use of the grapple to lift mattresses may be dangerous to personnel on the vessel deck as the load in recovered and there is a chance of snagging the underlying umbilical or pipeline as the mattress is grabbed and lifted from the seabed.
Therefore, a need exists to develop a recovery vehicle the can provide improvements over these systems when used.


A terminal block for interconnecting conductors in telecommunications circuits is disclosed. The terminal block allows a plurality of telecommunication wires to be progressively connected to a connector member. The terminal block includes a conductor transporting driver module having passageways that customer wires and service wires are inserted into and a connector chamber housing two insulation displacing connector members for the tip and ring lines. Wires are connected to the connector member progressively through a cyclical motion of the driver module relative to the connector members along a path of travel having an angle relative to a mounting surface which facilitates easy access to both wires and a threaded fastener actuating the driver module even in the most demanding telecommunications housing environments.

It is known to provide terminal blocks with connector members each having a slot for receiving and establishing electrical contact with a conductor such as a service wire, and also each having one or more additional slots each adapted to receive and establish electrical contact with respective ones of a plurality of other conductors, such as telecommunication customer wires, which need to be electrically connected to the service wire. The conductors customarily are and must be inserted simultaneously, as a group, into respective associated ones of the slots. Proper insertion of the conductors into the slots by a telecommunications craftsperson may be quite difficult, particularly when a large number of conductors are involved and/or when the insertion must be accomplished in adverse weather or lighting conditions. Furthermore, if the telephone company service or drop wire is electrically connected to the connector member while the craftsperson is working with the customer wires, the craftsperson may be exposed to shock from lightning or other stray voltages carried on the service wire.


A portable rotary tool includes a body having therein a drive device for rotation of a tool for working. The portable rotary tool further includes a handle which has an operation member mounted thereon for operation of the motor by an operator. A connecting device is provided for connecting the handle with the body and for permitting rotation of the handle relative to the body. The rotational position of the handle relative to the body may be fixed at any desired rotational position by a securing device.

1. Field of the Invention
The present invention relates to a portable rotary tool such as a disc grinder, a sander and a polisher.
2. Description of the Prior Art
A conventional rotary tool such as, for example, a disc grinder includes a body having a motor therein. A grinding wheel for rotation by the motor is mounted under the body at its forward portion. A handle is integrally formed with the rear portion of the body and includes therein a switch for controlling the motor. An operation member is mounted on the bottom of the handle or in the same direction as the grinding wheel. The operation member can be operated for starting the motor through the switch, so that the grinding wheel can be rotated for surface grinding of a work such as a metal material if the grinding wheel is one prepared for surface grinding.
In case that the disc grinder is to be used for cutting or grooving other works such as a concrete, a roof tile or other tiles, a brick and a stone, the grinding wheel is changed to one appropriate for cutting operation. In the practical operation by such grinding wheel appropriate for cutting, the rotary tool is positioned in such a manner that the grinding wheel abuts on the work substantially vertically to its surface. With such positioning of the rotary tool, the handle is turned sideways and therefore, the operation member is directed in a lateral direction (a direction perpendicular to the direction of movement of the grinding wheel for cutting into the work). This may cause difficulties in grasping the handle by an operator and in operating the operation member, so that the handling efficiency as well as the working efficiency may be decreased.
To resolve the above drawbacks, the prior art has proposed to provide a disc grinder having a motor housing and a gear housing which are connected with each other by screws. The motor housing includes a motor therein and is formed with a handle at its one end. The gear housing includes a gear mechanism therein for transmitting rotation of the motor to a grinding wheel. The motor housing and the gear housing can be fixed relative to each other with their positions angularly selectively displaced from each other at intervals of 90.degree. through removal of the screws. An operation member is mounted on the handle for operation of a switch for starting the motor and can be positioned on the side in a direction of movement of the grinding wheel for cutting into the work.
However, with this improved disc grinder, the screws must be completely removed and thereafter fastened again for each displacing operation. Such operation is very troublesome. Further, since the displacement is limited to the intervals of 90.degree., it does not satisfactorily meet various operation requirements.


A thermal transfer method includes a step of forming a donor member having a base layer, a light-to-heat conversion layer disposed on the base layer, an intermediate layer disposed on the light-to-heat conversion layer, an organic transfer layer disposed on the intermediate layer, and a first protecting film disposed over the base layer and contacting at least one edge of the base layer, irradiating a first laser onto the donor member to form a preliminary organic layer on the display substrate, forming a pressing member having a second protecting film and a third protecting film disposed over the second protecting film and contacting at least one edge of the second protecting film, disposing the display substrate within a space formed by the second protecting film and the third protecting film, and irradiating a second laser onto the pressing member to change the preliminary organic layer to an organic layer.

1. Field
Example embodiments relate generally to a technique for manufacturing an organic light emitting display device. More particularly, embodiments relate to a thermal transfer method, and a method of manufacturing an organic light emitting display device using the thermal transfer method.
2. Description of the Related Technology
An organic light emitting display (OLED) device usually includes various organic layers such as an organic light emitting layer, a hole injection layer, an electron transfer layer, etc. Recently, a laser induced thermal imaging (LITI) process has been developed to form the organic layers of the organic light emitting display device.
In a conventional laser induced thermal imaging process, a donor substrate including organic materials to be transferred onto a display substrate is placed on the display substrate in an atmosphere, and then a laser is irradiated onto the donor substrate to transfer the organic materials onto the display substrate, thereby forming organic layers on the display substrate.
However, the organic transfer layer may not be easily detached or separated from the donor substrate, so that the organic transfer layer may not be precisely transferred onto a desired region of the display substrate.

Thermal transfer method and method of manufacturing an organic light emitting display device using the same


An apparatus is provided which comprises: a chassis compartment having a bottom surface and walls orthogonal to the bottom, wherein the chassis compartment comprises: a rectangular opening, which may be designed to accept a microelectromechanical (MEMS) device and four slots, which may be designed to accept one or more magnet(s), extending outwardly from the rectangular opening, wherein each of the slots comprises: an inner opening having a length coextensive with a side of the rectangular opening, and an outer opening having corresponding ends that extend a length of the outer opening beyond the length of the inner opening. Other embodiments are also disclosed and claimed.

Users of electronic devices have come to expect richer experiences in terms of perceptual computing, augmented reality, and user interaction, for example. Delivering these enhanced user interfaces and experiences require the integration of more components and devices. At the same time, however, users have come to expect devices that are slimmer and sleeker. Integrating more components and functionality into smaller chassis can present challenges from a manufacturing perspective, particularly when dealing with magnets that can be difficult to place accurately due to attractive/repulsive forces.


Methods of detecting and recovering from communication failures within an operating network switching device that is switching packets in a communication network, and associated structures. The communication failures addressed involve communications between the packet processors and a host CPU over a shared communications bus, e.g., PCI bus. The affected packet processor(s)—which may be all or a subset of the packet processors of the network switch—may be recovered without affecting hardware packet forwarding through the affected packet processors. This maximizes the up time of the network switching device. Other packet processor(s), if any, of the network switching device, which are not affected by the communication failure, may continue their normal packet forwarding, i.e., hardware forwarding that does not involve communications with the host CPU as well as forwarding or other operations that do involve communications with the host CPU.

The present invention relates generally to communications error recovery, and in particular to recovery from communication errors in networking equipment having a shared control bus architecture.
Network switching equipment typically comprises a set of physical ports, one or more packet processors that receive data packets from and send packets to a physical port (or to a plurality of physical ports) of the network switching device via PHY and MAC circuitry, and a controller (typically CPU-based). The packet processors may be ASICs or FPGAs. The physical ports and packet processors (each of which has its own input and output ports) may be arrayed over a plurality of linecards, as in a chassis type unit, or on a single circuit board, as in a stackable unit. A received data packet can be processed and forwarded by a packet processor to another physical port coupled to an output port of the same packet processor. Alternatively, the received data packet can be forwarded by a receiving packet processor through a switching fabric to another packet processor to be further processed and forwarded via one of its output ports to a physical port of the switching device
During normal operation, there is occasional data communication between the respective packet processors and the CPU-based controller. The CPU-based controller may be on a separate management circuit board, such as in a typical chassis type network switching device, or on the same circuit board, as in a typical stackable type network switching device. In some network switching devices, there may be a dedicated controller for each packet processor or for a plural subset of the packet processors of the switching device In a cost optimized system, on the other hand, there may be one CPU-based controller for the whole system, e.g., for the entire set of packet processors of the network switching device. This centralized architecture is advantageous from a system-cost point of view, since there is only one CPU-based controller for all of the packet processors, but it poses some challenges, since there is a shared control bus coupling the CPU-based controller to the packet processors. The complex intercoupling of data structures between the controller and the packet processor that form the basis of controller-packet processor communication is susceptible to malfunctions that can render the system unusable.

This patent is subject to a terminal disclaimer.

Recovering from failures without impact on data traffic in a shared bus architecture


A combination target reflector, light emitter and bracket assembly is disclosed for use in marking points during the taking of a land survey. The combination is pivotally connected to a central rod of a target tripod or a tripod that supports a target reflector. The disclosed combination includes first and second arms and a light emitter that is held in axial alignment with the target reflector. The first arm is pivotally and perpendicularly connected to the central rod of the tripod. The second arm is perpendicularly connected to the target reflector and the light emitter. The tripod can be moved close to a point to be marked, the tripod can be adjusted to plumb the target reflector and then the second arms, light emitter and target reflector can be moved out of axial alignment with the rod to mark the point without moving the tripod. As a result, the conventional trial and error procedure currently employed can be avoided.

Land is surveyed to create a contour map or other graphical representation of the land based on linear and angular measurements. According to conventional practice, surveying is at least a two person job, with one person operating a measuring instrument, transit or total station from a generally stationary position and the other person transporting and positioning a rod or target that is sighted by the measuring instrument. To create a graded surface from a track of land, the land is marked or staked.
Relatively crude instruments were once used for land surveying. Surveyors used simple optical theodolites as transits to determine the horizontal azimuth angles and the vertical elevation angles between survey points. Chains and tape measures were used to measure the distance between the theodolite and a point to be established. Telescopic devices, e.g., horizontal levels and graduated rods were also used to determine the actual elevation of a point or location from a reference position.
Referring to FIG. 1, the transit 10, also known as the measuring instrument or station, is positioned at a known distance and angle from a reference or bench mark position. The target 11, also referred to as the "rod," is positioned at a location where it is leveled by the operator to ensure accurate measurements. As shown in FIG. 2, the target 11a may be placed upon a tripod 12 which includes a bubble measure (not shown) to ensure that the tripod 12 is level. At each such location, the distance and angle of the target 11a with respect to the position of the transit 10 is determined and recorded. Distances were traditionally measured manually with a steel tape or chain.
In contrast, modern transits may incorporate electronic distance measurement (EDM) technology in the form of laser and/or infrared beams in combination with retro-reflective devices, such as corner cube prisms, in the determination of precise distances. In addition to or as an alternative to EDM, modern transits can incorporate global positioning satellite (GPS) technology. FIG. 3 schematically illustrates a modern transit station 10a that may be linked optically to the target reflector 13 as well as being communicatively linked to a GPS 14 and a receiver 15 mounted to a tripod 12a. The transit 10a also includes a receiver 19. The target receiver 15 typically includes a display 16 and/or a speaker 17, both of which can provide an indication to the rod operator that the target 13 and rod 11b are disposed in the correct location for marking. It will be noted that the target 13 is mounted directly above the rod 11b. The reflector 13 may also include some sort of transmitter for communicating with the GPS system 14 and/or the transit 10a. The target receiver 15 may also be optically or otherwise communicatively linked to the target 13, GPS system 14 and the transit 10a. The beams originating at the transit 10a are reflected by the target/reflector 13 as parallel collinear beams of energy back to the transit receiver 19. Phase angle measurements and timing circuits allow the exact distance between the transit 10a and reflector 13 to be precisely determined and displayed. Such electronic instruments have greatly improved the accuracy of the measurements and the setting of points. EDM devices can be used to provide accurate measurements even though the reflector or prism targets 13 are two or three thousand feet away from the transit 10a.
Still referring to FIG. 3, to mark a point, the target 13 is positioned near a location to be marked, and its position is determined by the transit 10a. If the target 13 is not exactly positioned at the location to be marked, the position is noted and the target 13 is repositioned and re-measured until the measuring transit 10a and/or target receiver 15 verifies that the tripod 12a is positioned at the precise location to be marked. A stake 21 or other marker is then driven into the ground at that point. However, as explained below, the process of accurately placing the stake 21 into the ground 22 as the desired point is problematic.
Specifically, once the operator has placed the target 13 and rod 11b in the correct location, the operator then sets the legs 18 into position and manipulates the tripod 12a until the rod 11b and target reflector 13 are plum or vertical. Typically, the tripod 12a may be equipped with a plumb bob or level (not shown). The receiver 15 communicating with the transit 10a may also communicate to the operator that the rod 11b and target 13 are plum or vertical. At this point, with the rod 11b and target 13 in a plumb or vertical position and after being assured by the transit 10a or target receiver 15 that the rod 11b and target 13 are in the correct location, the operator must then move the rod 11b to place a stake 21 in the ground 22 in the exact location from which the rod 11b has just been moved. To do this, the skilled operator will move the rod 11b, keep his or her eye on the spot on the ground 22 where the stake 21 should be placed, insert the state 21 into the ground, and then replace the rod 11b and tripod 12a back into the position to confirm that the stake 21 is in the correct position. Often, the operator does not place the stake 21 in the exact desired location and the stake 21 must be moved, and the process repeated until the correct location of the stake 21 is verified. This trial and error process is typically repeated a number of times before the accuracy of the placement of the stake 21 are confirmed.
Referring to FIG. 4, the use of a rod 11c and target 13 without a tripod is even more difficult. Target rods 11c without tripods typically may include a sharp distal end 23 that puts a preliminary visual mark on the ground 22. However, the preliminary mark may be difficult to see if the ground surface is rough, wet, grassy, etc. Further, ensuring that the rod 11c is plum or vertical can be time-consuming unless the operator is skilled or experienced. Typically, placing the stake 21 in the correct location also requires the same trial and error process described above in connection with FIG. 3.
Thus, even with the advent of EDM, GPS, electronic transits 10a, electronic target receivers 15 and target reflectors 13, one prominent problem associated with currently available targets 13 mounted on either rods 11c or tripods 12a lies in the trial and error process used by operators to accurately place the mark 21 into the ground. Obviously, the above procedure is cumbersome, repetitive and time consuming. These problems are exacerbated when dozens or hundreds of marks must be placed for larger tracts. As a result, there is a need for methods and apparatuses for more rapid and accurate marking of surveyed land.

Reflector target tripod for survey system with light emitter and pivoting bracket for enhanced ground marking accuracy


A clamping circuit with a low-pass filter inserted in a feedback loop from an output terminal of a comparator to variable current sources for obtaining a feedback signal having only a DC component or having only a substantial portion of a DC component obtained by removing an AC component due to a burst signal from the output signal of the comparator.

In general, average potential of video signals varies according to the information it contains, especially according to the brightness of the video signals. Therefore, a clamping circuit (described as a pedestal clamping circuit hereinafter) is generally provided in a semiconductor integrated circuit used for processing video signals, in order to keep a sink chip DC (DC indicates a direct current hereinafter) potential or a pedestal DC potential at a constant value.
This pedestal clamping circuit requires a clamping pulse synchronized to a timing of a pedestal signal to maintain a pedestal level at a constant DC potential. For a period when this clamping pulse is received in the pedestal clamping circuit, comparison is made between a pedestal DC potential of an input video signal and a DC potential of a clamping target (described as a reference potential hereinafter).
The difference obtained through the comparison is fed back, and the potential of the DC component of the video signal is adjusted according to the difference, by which the pedestal DC potential can be kept constant. Accordingly, when a timing of a clamping pulse is displaced from a timing of a pedestal signal, the pedestal signal can not be clamped to a desired DC potential.
FIG. 7 shows a simulated view of a pedestal clamping circuit based on the conventional technology. This pedestal clamping circuit comprises an input terminal 11 to which a video signal is inputted from an external device, a resistor 12 with one terminal thereof connected to the input terminal 11, a comparator 13 with a reversed input terminal thereof connected to the other terminal of the resistor 12, a constant voltage power unit 14 for loading a reference potential Vped to a non-reversed input terminal of the comparator 13, a pair of variable current sources 15, 16 connected to the other terminal the resistor 12 and an amount of current of each of which is controlled by output from the comparator 13, and a feedback capacitor 17 connected to an output terminal of the comparator 13.
A clamping pulse is inputted into the comparator 13 at a specified timing. Output from the pedestal clamping circuit can be obtained at the other edge of the resistor 12. The variable current source 15 is connected between the other edge of the resistor 12 and a positive supply voltage Vcc, while the variable current source 16 is connected between the other edge of the resistor 12 and a ground GND.
Effects due to the pedestal clamping circuit shown in FIG. 7 are explained. A video signal having been inputted from the input terminal 11 is then inputted to the reversed input terminal of the comparator 13 through the resistor 12. The video signal inputted into the comparator 13 consists of a pedestal signal to which a burst signal is superimposed as a reference for a color density or a color tone. The comparator 13 compares a potential of a video signal to the reference potential Vped during a period when a clamping pulse is received (e.g., a period when a clamping pulse is a relatively high potential level (described as a "H (high)" level hereinafter)), generates and outputs a feedback signal S1 according to the difference and outputs. The feedback signal S1 is fed back to the variable current sources 15, 16.
As a result of the feedback, when a potential of the video signal is lower than the reference potential Vped, current flows into the resistor 12 from the variable current source 15 which is at a higher potential so that the potential of the video signal is higher. On the contrary, when the potential of the video signal is higher than the reference potential Vped, current is drawn out from the resistor 12 by the variable current source 16 which is at a lower potential so that the potential of the video signal becomes lower. Thus, the resistor 12 and the variable current source 15 form a positive potential loading unit, while the resistor 12 and the variable current source 16 form a negative potential loading unit.
The capacitor 17 is charged or discharged according to an output from the comparator 13. This capacitor 17 maintains the charged state for a period when a clamping pulse is not received (e.g., a period when a clamping pulse is at a relatively low level (described as a "L (low)" level hereinafter)).
FIG. 8 shows a detail circuit configuration of the pedestal clamping circuit. This pedestal clamping circuit has an emitter-follower circuit 21 comprising an NPN transistor Tr1. A positive power voltage Vcc is applied to the collector of the NPN transistor Tr1 of this emitter-follower circuit 21, the emitter is branched and connected to one terminal of the resistor 12 and to the ground GND through another resistor 22, and a video signal is inputted into the base thereof.
This pedestal clamping circuit has a differential amplifier. The differential amplifier comprises a constant current source 23 connected to a power line with a positive power voltage Vcc applied thereto, a differential pair 24 of PNP transistors Tr2, Tr3 the emitters of each of which are connected to the constant current source 23, and a current mirror circuit 25 comprising a pair of NPN transistors Tr4, Tr5 connected to the differential pair 24 respectively. The differential pair 24 and current mirror circuit 25 correspond to the variable current source 15 and to the variable current source 16 shown in FIG. 7 respectively.
A specified bias potential is applied to the base of the PNP transistor Tr2 by a DC bias source 26. Inputted to the base of the PNP transistor Tr3 is an output from a circuit constituting a comparator described later. Collectors of the PNP transistors Tr2, Tr3 are connected to the collectors of the NPN transistors Tr4, Tr5.
The base terminals of the pair of NPN transistors Tr4, Tr5 are connected to the collector of the PNP transistor Tr3 in the side where output (namely a feedback signal S1) from a circuit constituting the comparator described later is inputted to the base thereof in the differential pair 24. Namely, in the NPN Transistor Tr5 connected to the side where output from the comparator described later of the current mirror circuit 25 is inputted to the base thereof, the base and the collector thereof are short-circuited. Each emitters of the pair of NPN transistors Tr4, Tr5 is connected to the ground GND.
The other terminal of the resistor 12 is connected to the output from the differential amplifier comprising the constant current source 23, differential pair 24 and current mirror circuit 25. In addition, the output from this differential amplifier is supplied to an external device, branched and inputted to a differential pair as one of circuits constituting the comparator described later.
The comparator comprises a current mirror circuit 27 comprising a pair of PNP transistors Tr6, Tr7 each having an emitter connected to the power line with a positive voltage Vcc loaded thereto; a differential pair 28 of NPN transistors Tr8, Tr9 connected to the current mirror circuit 27; and a constant current source 29 to which emitters of the NPN transistors Tr8, Tr9 constituting the differential pair 28 are connected through a switching element 30.
This comparator corresponds to the comparator 13 shown in FIG. 17. The output from this comparator is supplied to the base of the PNP transistor Tr3 constituting the differential pair 24 of the differential amplifier as described above, branched and supplied to the feedback capacitor 17. The other terminal of the constant current source 29 is connected to the ground GND.
The base terminals of the pair of PNP transistors Tr6, Tr7 are connected to the collector of the PNP transistor Tr7. Namely, in the PNP transistor Tr7 which is one of the two transistors constituting the current mirror circuit 27, the base and the collector are short-circuited. Each collectors of the PNP transistors Tr6, Tr7 are connected to the collectors of NPN transistors Tr8, Tr9 respectively.
A reference potential Vped is applied by the constant voltage power unit 14 shown in FIG. 7 to the base of the NPN transistor Tr9, connected to the line of the PNP transistor Tr7 with the base and collector short-circuited in the current mirror circuit 27. The base of the other NPN transistor Tr8 is connected to the other terminal of the resistor 12 as well as to the output terminal of the differential amplifier, and a video signal is inputted to the base terminal.
The switching element 30 whose opening and closing is controlled by the clamping pulse is provided. The switching element 30 is closed, for instance, when the clamping pulse is at the "H" level, and is opened when the clamping pulse is at the "L" level. Accordingly, only when the clamping pulse is at the "H" level, the comparator comprising the current mirror circuit 27, differential pair 28 and the constant current source 29 operates.
FIG. 9 shows a relation between the timing of a video signal and a clamping pulse. When the clamping pulse is ON, namely when it is at "H" level, the comparator comprising the current mirror circuit 27, differential pair 28 and the constant current source 29 compares the reference potential Vped supplied by the constant voltage power unit 14 to a pedestal potential of a video signal. The capacitor 17 charges or discharges according to the result of the comparison, and the result is maintained by the capacitor 17 when the clamping pulse is OFF, namely when it is at the "L" level. On the other hand, the differential amplifier comprising the constant current source 23, differential pair 24 and the current mirror circuit 25 controls a current passing through the resistor 12 according to the voltage maintained by the capacitor 17.
Thus, when a pedestal potential is higher than the reference potential Vped, the capacitor 17 is discharged and the voltage decreases. When input to the differential amplifier is lower than the reference potential (a specified bias potential applied by the DC bias source 26) of the differential amplifier, the current mirror circuit 25 works so that a current is drawn from the resistor 12. As a result, a pedestal DC potential at the output terminal decreases.
On the other hand, when the pedestal potential is lower than the reference potential Vped, the capacitor 17 is charged and the voltage increases. Then, when input to the differential amplifier is higher than the reference potential (a specified bias potential applied by the DC bias source 26) of the differential amplifier, the differential pair 24 works so that a current is supplied to the resistor 12. As a result, a pedestal DC potential at the output terminal increases. As a result of the feedback as described above, the pedestal potential of the video signal to be outputted is equal to the reference potential Vped.
Clamping circuits are disclosed, for instance, in Japanese Patent Laid-Open Publication No. HEI 8-98057, Japanese Patent Laid-Open Publication No. HEI 8-195894 and Japanese Patent Laid-Open Publication No. HEI 3-226074.
In a case of an actual complex video signal, a burst signal exists in a front porch section thereof. The burst signal occupies, as shown in FIG. 9, most of the pedestal section in the complex video signal and it is extremely difficult to set a clamping pulse in portion where the burst signal is absent. Accordingly, a burst signal exists in the clamping period set by a clamping pulse. A frequency of the burst signal is around 3.58 MHz (or around 4.43 MHz), and a comparator generally reacts to a signal at this frequency.
Accordingly, in the pedestal clamping circuit shown in FIG. 7 and FIG. 8, as a result of comparison between the reference potential Vped and a potential of a video signal in a comparator, an AC component derived from the burst signal is outputted together with a feedback DC voltage to a terminal of the feedback capacitor, as shown in FIG. 10, as a result of which the comparator tries to convert the burst signal to a DC current. Hence, the burst signal in the output video signal is attenuated as compared to that in the input video signal, which results in the fact that the burst signal is damaged. Further, phase of the burst signal may be changed.
Although this drawback can be overcome by using a feedback capacitor having a larger capacitance, the clamping speed becomes extremely slow, and this is not practical.
Also, there is found no consideration on a burst signal included in a video signal in the clamping circuits disclosed in Japanese Patent Laid-Open Publication No. HEI 8-98057, HEI 8-195894 and HEI 3-226074, so that, when a burst signal is superimposed on a pedestal signal, it is not clear whether the pedestal potential can be clamped to a specified reference potential without any damage to the burst signal or not.


A disposable box filter having a housing having mating channel-shaped male and female portions defining a generally box-shaped fluid chamber, with a pair of fluid ports, and a filter element in corrugated sheet form extending across the fluid chamber. The corrugated filter has generally vertically extending pleats or extremities which are mechanically sealed at each end between a pair of vertical axially extending portions of the filter housing.

1. Field of the Invention
The present invention relates to filters and filter housings. More particularly, the present invention relates to a disposable box filter useable in medical and other applications which is of low cost and capable of being made absolutely sterile before use.
2. Description of the Prior Art
Box filters, because of their unique configuration, low cost, and ease of manufacture, have been found very useful in medical applications, as well as in other applications. It is quite important in medical applications that a filter be capable of being made absolutely sterile before use. To avoid the necessity of cleaning and sterilizing operations after use, it is also desirable that the filter be disposable. For a filter to be disposable, it must necessarily be of low cost. Many attempts at making a true, low cost, disposable box filter have been found in the prior art. None of them have been entirely successful.
One such prior art patent is the U.S. Pat. No. 3,765,537. While this filter is satisfactory in use, it has significant limitations which arise during the manufacturing process. The filter sheet is held tightly between an internal wall and a top wall of the filter housing and is bonded in place. This requires an open pore filter sheet. This limits the type of filter element that can be used in the housing, and also increases the manufacturing cost.
Another such attempt in the prior art is shown in U.S. Pat. No. 3,815,754. In an attempt to eliminate the limitations imposed by having to bond through open pores of the filter sheets, this patent attempts simply to pinch the sheet between an inner wall of the housing and the ends of a pair of vertical walls. While this design eliminated the limitation on the type of filter element that could be used to obtain a sufficient seal, the resultant filter was found not suitable for use at relatively high pressure differentials.
In an attempt to solve the problems of the prior art still present after the inventions disclose in U.S. Pat. Nos. 3,765,537 and 3,815,754, the filter shown in U.S. Pat. No. 4,187,182 was developed. In this patent, the filter sheet is pinched between the edge of the inner side walls and other portions of the housing. However, this filter increases manufacturing expense by requiring the pleats of the corrugated filter element to be trimmed specially at positions midway of the height of the filter element, thus increasing greatly the manufacturing costs.
Thus, those skilled in the box filter art continued to search for a solution to the problem of providing a truly low cost disposable box filter.


Systems and methods for management of network slices in a communication network such as a 5th generation wireless communication network are provided. Network slicing formats of varying degrees of specificity are defined. An appropriate format may be selected for definition of a network slice. Different segments of a slice can be defined using different formats. Slice scoping, purposing, granularity, and resource usage are described. Slice creation and adaptation, and cloud resource management are also described.

Communication networks enabled by technologies such as Network Function Virtualization (NFV), and Software Defined Networking (SDN) can be flexibly organized so as to serve various customer demands. Network slicing has been proposed as a means to offer network services in wireless networks. Through the use of NFV, and network slicing, a dynamic network responsive to the immediate needs of the users can be provided. Various architectural and implementation issues remain to be addressed within the domain of network slicing for communication networks in order to properly define an architecture that is sufficiently scalable and reliable for next generation wireless networks.
Therefore there is a need for a method and apparatus for network slicing, that obviates or mitigates one or more limitations of the prior art.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.

Method and apparatus for network slicing


A micro-catheter delivery system that includes radio-opaque marker bands optimized for the purpose of length reference to assist the operating physician to estimate the length of a tortuous lesion and to anticipate foreshortening of stents with multiple sizes. The radio-opaque maker bands are positioned at the distal end of a stent delivery catheter at a certain intervals acts like a ruler. In another embodiment, a stent delivery system includes a stent delivery wire with one or more radio-opaque markers distanced from the stent distal end for indicating the non-restrained length of the stent when discharged from the delivery catheter.

1. Field of the Invention
This invention pertains generally to endovascular delivery systems and methods, and more particularly to systems and methods for delivery of expandable stents.
2. Description of Related Art
Current endovascular procedures use a metallic expandable stent to expand a lesion or to cover a target lesion. There is an increase in the use of stents due to advancements in biomaterial technology. For example, intracranial aneurysms had been treated only by endovascular coiling or open-surgical clipping until recently; but now those aneurysms can also be treated by using a stent that reduces the blood flow into the target aneurysm and induces complete thrombosis. In order to successfully treat an aneurysm with a stent, it is crucial to cover the aneurysm lesion completely with the stent. Any uncovered area in the aneurysm neck may make the stent procedure ineffective. Therefore, if an uncovered area occurs, an additional stent may need to be placed to completely cover across the aneurysm lesion. This applies not only to aneurysms, but also to stenotic/narrowing lesions. An atherosclerotic plaque covered by a stent should bridge the proximal to the distal normal arterial segment. Thus, the capacity to accurately place a stent across the lesion is a critically important element in endovascular stenting procedure.
There are generally two different types of stents: a laser-cut stent and a braided stent. There are pros and cons for each type of the stent. The most significant limitation of a braided stent is a phenomenon called "foreshortening," which is defined as the change in the length of the stent from a constrained (i.e. compressed) state to an unconstrained (i.e. expanded) state. Although the degree of foreshortening is most significant in a braided stent, it may occur in a micro-machined or laser-cut stent as well. The degree of foreshortening with certain kinds of braided stents can be as large as 100%. This foreshortening poses a challenge to the treating physicians to place a stent very accurately.
Referring to FIG. 1, a stent is generally delivered to a target lesion via a catheter and delivery wire 12. When a braided stent is squeezed in a delivery catheter, the stent becomes longer (elongated stent 10b). Once the stent is being pushed out of the delivery catheter, the stent expands in the target vessel and it becomes shorter (foreshortened stent 10a). This foreshortening phenomenon must be taken into account when a braided stent needs to be placed in a lesion with high accuracy. A physician must therefore anticipate the degree of foreshortening during the stent placement, which requires a certain amount of training and clinical experiences. Nevertheless, it is virtually impossible to achieve 100% accuracy as long as the procedure depends on "anticipation" or "experience."
Another challenge for the accurate stent placement is tortuous anatomy. It is difficult to control the position of delivery catheter and also to anticipate the shape and position of a stent in a curvy target lesion. Endovascular stenting procedures are performed under a 2-dimensional fluoroscopic X-ray imaging guidance. Even with the use of multiple angle fluoroscopic images (for example, bi-plane digital subtraction angiography machine), there is an intrinsic challenge in making a real time estimate on the length of a lesion in a tortuous 3-dimensional anatomy projected onto a 2-dimensional fluoroscopic view.

Apparatus and methods for precise stent placement

THE REGENTS OF THE UNIVERSITY OF CALIFORNIA


The clamp mounts a cable and service lines in spaced relationship to a tubing string used in producing a well, and formed of lengths of tubing joined by a coupling. The clamp comprises first and second clamping elements for clamping around the tubing string and hinged on a first pin. A cover is hinged to the first element by a second pin. The first element and the inner surface of the cover are provided with formations which ensure that the cable and service lines are firmly held when the cover is closed against the first element by a captive bolt, which also clamps the first and second elements firmly around the coupling. A single hinge pin version clamps to the tubing string on each side of a coupling.

This invention relates to clamps for use with completion or production tubing strings deployed in oil, gas or water wells.
The completion of a well using tubing conveyed tools and the subsequent production thereof with or without the use of a submersible pump suspended on a production tubing string require the installation of an electric power cable and/or service lines, for example control or injection lines, alongside the tubing string. Clearly, these cable and/or service lines are liable to be damaged during running-in and removal from the well, particularly by crushing from side loads imposed by movement in deviated wells.
It is common practice to use clamps to maintain the cable and/or lines in a pre-determined path in the space between the tubing string and the well casing, the clamps either being secured to the tubing string between couplings or spanning a coupling. Such clamps, as described for example in UK Patent Application No 2 149 000 A (Lasalle) reduce the tensile stresses to which the cable and service lines are subject by virtue of their own weight. However, conventional clamps function by compressing the cable and service lines against the tubing string. This arrangement has the drawback that the contact surfaces between the cable and lines and the tubing string are quite limited, and the support afforded is dependent on the actual diameter of the tubing string.


Methods and devices create a first halftone image and a different second halftone image from a continuous tone image. A third halftone image is produced by identifying pixels that are common to both the first and second halftone images. A toner reduction mask is applied to the third halftone image to produce a fourth halftone image (the fourth halftone image has only holes and remaining ones of the common pixels). The holes are added to the first halftone image to create a reduced-toner halftone image. Further, edges of features within the continuous tone image are detected (to identify edge pixels of the edge features) and such edge pixels are added to the reduced-toner halftone image to produce a print-ready halftone image. Finally, such methods print the print-ready halftone image on print media.

Devices and methods herein generally relate to reducing the amount of marking material used in printing, and more particularly to achieving such reductions using threshold arrays and a toner reduction mask.
Reducing the usage of toner in printers, especially in color printers, increases toner yield. Some systems for reducing toner usage decrease the halftone frequency (which decreases image quality), adjust the tone reproduction curve (TRC) (which decreases contrast and image quality), use neighborhood processing to decide which pixel are to be turned on/off (which increases processing complexity), optimize print engine and image output terminal (IOT) components for better toner yields, etc. Additionally, some methods affect only the darker regions of images, which can prevent toner savings from being as high as expected.
Such toner saver methods can have a significant effect on image quality, and present a tradeoff between image quality and toner savings. The goal of such systems is to identify methods that will give greater toner savings, without sacrificing quality image.

Saving marking material using threshold arrays and toner reduction mask