The present invention apparatus for joining sheet material provides a stepped punch (38). This stepped punch (38) serves to strengthen a joint (14) between two or more sheets of material (16 and 18) by creating a stepped segment (122) in at least one of these sheets of material. During formation of this stepped segment (122), material is forcibly displaced toward another segment of material that is outwardly expanded to interlock with the adjacent sheet of material.

The present invention relates generally to an apparatus for joining sheet material and specifically to a punch and a joint, each having a step therein.
It is common within the metal forming industry to join pieces of sheet metal by punching or otherwise deforming them to cause an interlocking relationship in a localized area. However, these traditional joints have typically required shearing of the sheet material. Thus, these joints tend to leak and also have their corrosion resistant coatings destroyed.
More recently, an apparatus has been used for joining two or more sheets of material together by creating a leakproof and secure joint. These improved conventional joints are created by use of a punch acting against an anvil to produce what is known as a TOG-L-LOC.RTM. joint therebetween. Such a leakproof joint is disclosed in U.S. Pat. Nos. 5,267,383 and 5,177,861, both of which are entitled "Apparatus for Joining Sheet Material" and issued to Sawdon. The disclosures of these patents are incorporated by reference herewithin.
The conventional TOG-L-LOC.RTM. leakproof joints consist of two or more sheets of material having a button or joint formed therebetween by a uniformly cylindrical punch forcibly pushing a punch side sheet of material into interlocking engagement with a die side sheet of material. These conventional leakproof joints have seen tremendous commercial success for use in varied applications such as steel microwave ovens and aluminum automotive bodies. While these leakproof joints have proven reliable and inexpensive, it would be desirable to have an even stronger leakproof joint.
In accordance with the present invention, an improved apparatus for joining sheet material provides a stepped punch. This stepped punch serves to strengthen a joint between two or more sheets of material by creating a stepped segment in at least one of these sheets of material. During formation of this stepped segment, material is forcibly displaced toward another segment of material that is outwardly expanded to interlock with the adjacent sheet of material.
The punch and joint of the present invention are advantageous over conventional punches and joints by achieving a surprisingly stronger leakproof joint. Furthermore, the joint of the present invention has improved wall thickness that is more resistant to fracture as compared to conventional leakproof joints. The punch, joint and method of the present invention thus reduce scrap during the joint forming process. Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.

Apparatus for joining sheet material and joint formed therein


A display device and an image compensation method are disclosed. One inventive aspect includes a controller and a data driver. The controller processes image data signal based on at least one of pixel information, a reference brightness condition, a present brightness of the display device and a target luminance and generate final compensated data. The pixel information is measured under the reference brightness condition. The data driver transmits the final compensated data to an activated driving pixel.

1. Field
The disclosed technology generally relates to a display device including an image compensation system and a method for compensating images to be displayed.
2. Description of the Related Technology
An organic light emitting diode (OLED) is a self-luminance element that makes a phosphorous material emit light by re-combination of electrons and holes. Thus, unlike a passive light emission element that requires an additional light source like a liquid crystal display, OLED technology has fast response time and requires low DC driving voltage. In addition, OLEDs can be formed into slim profiles so that they can be applied in a wall mounted or portable display device.
OLEDs are generally classified into passive matrix type organic light emitting diodes (PMOLEDs) and active matrix type organic light emitting diode (AMOLEDs) that use a TFT to drive each OLED pixel. A PMOLED forms a positive electrode and a negative element which perpendicularly cross each other and selects a line for driving. An AMOLED connects a TFT and a capacitor to an ITO pixel electrode to maintain a voltage.
A display device using OLED pixels has a luminance difference due to non-uniform deterioration or aging of the pixels. Such a luminance non-uniformity may also naturally occur in chemical batch characteristics or performance of OLED materials.
Various methods for reducing screen non-uniformity due to luminance difference between pixels have been researched. It is known that when luminance non-uniformity of a display device is modulated based on data measured in a specific screen brightness, the non-uniformity can be reduced for brightness when the data is measured. However, the improvement can be inefficient or the non-uniformity can increase for brightness other than the brightness when the data is measured. Therefore, a method for reducing the luminance non-uniformity for any brightness condition is desirable.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Display device and method for compensation of image data of the same


An integrated circuit device comprising a partially embedded and encapsulated damascene structure and method for forming the same to improve adhesion to an overlying dielectric layer, the integrated circuit device including a conductive material partially embedded in an opening formed in a dielectric layer; wherein said conductive material is encapsulated with a first barrier layer comprising sidewall and bottom portions and a second barrier layer covering a top portion, said conductive material and first barrier layer sidewall portions extending to a predetermined height above an upper surface of the dielectric layer to form a partially embedded damascene.

In typical multi-layer semiconductor device, electrical interconnects including vias, interconnect lines, and bonding pads are formed in dielectric layers by embedding a conductive material in openings formed in the dielectric layer.
A process wafer typically includes a semiconductor substrate including active semiconductor devices formed thereover, followed by the formation of multiple layers of conductive wiring including vias and trench lines, and including uppermost layers having bonding pads for subsequent electrical interconnection by various methods to external circuits.
Following device formation in individual die areas on a wafer, the process wafer is subjected to various operations including wafer acceptance testing (WAT), dicing operations to form individual die, die interconnection bonding processes into packaged chips and the like, where the multi-layer device is subjected to both thermal and mechanical stresses including shear force components directed parallel to a layer thickness. The shear forces applied to the semiconductor device by the various processing operations can lead to catastrophic peeling of one or more layers of the multi-layer semiconductor device.
The problem is exacerbated where low-K (low dielectric constant) dielectric layers are used, as the low-K materials are typically less mechanically robust and have poor adhesion to overlying material layers. For example, the shear modulus (resistance to shear force) of the multi-layer device is crucial during die formation and assembly into packaged chips. While prior art approaches have been proposed to solve this problem, the approaches to date have been less than adequate in forming a multi-layer semiconductor device with adequate resistance to shear forces, leading to less than adequate device yield and reliability.
There is therefore a need in the semiconductor device integrated circuit manufacturing art to develop a multi-layer semiconductor device including embedded conductive features with improved structural stability and resistance to shear forces.
It is therefore an object of the invention to provide a multi-layer semiconductor device including embedded conductive features with improved structural stability and resistance to shear forces, while overcoming other deficiencies and shortcomings of the prior art.

Encapsulated damascene with improved overlayer adhesion

Taiwan Semiconductor Manufacturing Co., Ltd


A panel with pattern block bead for a car body includes a plurality of beads. The panel is divided into four division panels by a first substantially horizontal reference line and a first substantially vertical reference line each passing through a center of the panel. One of the beads is formed at a center of each of the division panels.

In general, a car body panel, for example, a center floor panel can satisfy a NVH (Noise Vibration Harshness) performance which is an item characteristic of habitability and comfort of a car only when the car body panel has a structure which can secure a rigidity as well as properly interrupt a noise entering a room.
The center floor panel is installed on a bottom of a middle portion in the car body, and has a structure which increases panel rigidity as well as interrupts the noise entering the room by forming at a regular interval a rigidity increasing foaming on the center floor panel constructed in one piece, and by attaching a pad on the center floor panel or carrying out a rust preventing coating treatment.
FIG. 1 shows a conventional center floor panel such as a curved panel structure having double curvatures, an embo panel structure, and a general bead structure.
However, the conventional structure was an efficient structure in the low frequency area but had a disadvantage in the intermediate frequency area and the high frequency area.
This structure had to apply a vibration reduction material to improve the intermediate frequency performance and the high frequency performance, thereby having a disadvantage in view of weight and cost.
Therefore, there is a need for an optimized structure preferable in view of weight and cost by minimizing the amount of application of vibration reduction material while securing the NVH performance not only in the low frequency area but also in the intermediate frequency area and the high frequency area.
Technologies which are background of the present invention are disclosed in Japanese laid-open patent publication Hei 9-202269, US laid-open patent publication 2006-163914, Japanese laid-open patent publication 2011-130174, and Japanese laid-open patent publication 2004-255983.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Panel with pattern block bead for car body


Disclosed herein is a noise reduction method for automatic speech recognitionl. A noise reduction method for automatic speech recognition, including: computing a magnitude spectrum of a noisy speech containing a clean speech to be recognized and noise affecting the clean speech; computing a power spectrum of the noisy speech; computing an estimate of a power spectrum of the clean speech; computing an estimate of a power spectrum of the noise; computing an estimate of an a priori signal-to-noise ratio as a function of the estimate of the power spectrum of the clean speech and the estimate of the power spectrum of the noise; computing an estimate of an a posteriori signal-to-noise ratio as a function of the power spectrum of the noisy speech and the estimate of the power spectrum of the noise; computing an attenuation gain as a function of the estimate of the a priori signal-to-noise ratio and the estimate of the a posteriori signal-to-noise ratio; and computing an estimate of a magnitude spectrum of the clean speech as a function of the magnitude spectrum of the noisy speech and the attenuation gain. Computing the estimates of the a priori and the a posteriori signal-to-noise ratios includes computing a noise weighting factor for weighting the estimate of the power spectrum of the noise in the computation of the estimates of the a priori and the a posteriori signal-to-noise ratios; computing a spectral flooring factor for flooring the estimates of the a priori and the a posteriori signal-to-noise ratios; and computing the estimates of the a priori and the a posteriori signal-to-noise ratios also as a function of the noise weighting factor and the spectral flooring factor.

FIG. 1 shows a block diagram of common sources of speech degradation. As may be appreciated, speech from the desired speaker (block 10) is degraded by environmental noise, namely voices of other speakers nearby (block 20) and background noise (block 30), and by communication channel noise and distortion (blocks 40 and 50). Noise reduction techniques (block 60) for automatic speech recognition (block 70) can reduce the (nearly stationary) background noise and the channel noise, whereas non-stationary noise and interfering voices are much more difficult to be eliminated.
FIG. 2 shows a block diagram of an automatic speech recognition system. As may be appreciated, the noisy speech to be recognized is inputted to a short-time spectral analysis (windowed FFT) block 100 which outputs short-time spectra which is in turn inputted to a noise reduction block 110. The de-noised short-time spectra are inputted to a RASTA-PLP Front-End 120, which outputs the total energy of the speech signal, the cepstral coefficients, and the first and second derivatives of the total energy and of the cepstral coefficients, which are all inputted to an automatic speech recognition block 130.
RASTA-PLP Front-End 120 implements a technique known as "RelAtive SpecTrAl Technique", which is an improvement of the traditional PLP (Perceptual Linear Prediction) method and consists in a special filtering of the different frequency channels of a PLP analyzer. The previous filtering is done to make speech analysis less sensitive to the slowly changing or steady-state factors in speech. The RASTA method replaces the conventional critical-band short-term spectrum in PLP and introduces a less sensitive spectral estimate. For a more detailed description of a RASTA processing, reference may be made to H. Hermansky and N. Morgan, RASTA Processing of Speech, IEEE Transactions on Speech and Audio Processing, Vol. 2 No. 4, October 1994.
The noise reduction block 110 performs an environmental noise estimate 112 based on the short-time spectra and then an environmental noise reduction 114 based on the short-time spectra and the estimated noise, by using either a so-called "Spectral Subtraction Technique" or a so-called "Spectral Attenuation Technique".
The aforementioned techniques will be described in detail hereinafter by denoting the power spectrum of the noisy speech by |Yk(m)|2, the power spectrum of the clean speech by |Xk(m)|2, the power spectrum of the additive noise by |Dk(m)|2, and the estimate of a quantity by symbol "^", and wherein k indexes the spectral lines of the spectra and m indexes the time windows within which the noisy speech is processed for noise reduction.
Spectral Subtraction Technique is described in N. Virag, Single Channel Speech Enhancement Based on Masking Properties of the Human Auditory System, IEEE Transaction on Speech and Audio Processing, Vol. 7, No. 2, March 1999, which deals with the problem of noise reduction for speech recognition and discloses the use of a noise overestimation or oversubtraction factor and a spectral flooring factor.
In particular, the Spectral Subtraction Technique is based on the principle of reducing the noise by subtracting an estimate |{circumflex over (D)}k(m)|2 of the power spectrum of the additive noise from the power spectrum |Yk(m)|2 of the noisy speech, thus obtaining an estimate |{circumflex over (X)}k(m)|2 of the power spectrum of the clean speech:
                                                                                                      X                  ^                                k                                                          (                m                )                                                          2                =                  {                                                                                                                                                              Y                            k                                                                                (                            m                            )                                                                                                                      2                                        -                                                                  α                                                                          (                          m                          )                                                                                                                                                                D                                ^                                                            k                                                                                (                              m                              )                                                                                                                                2                                                                                if                                                                                                                                                                Y                                k                                                                                (                                m                                )                                                                                                                                    2                                                                    -                                                                        α                                                                                (                            m                            )                                                                                                                                                                D                                  ^                                                                k                                                                                (                                m                                )                                                                                                                                    2                                                                                >                                                                  β                                                                          (                          m                          )                                                                                                                                                                Y                              k                                                                                (                              m                              )                                                                                                                                2                                                                                β                                                                    (                        m                        )                                                                                                                                                              Y                            k                                                                                (                            m                            )                                                                                                                      2                                                                                otherwise                                                                                (        1        )            wherein α(m) is the noise overestimation factor, β(m) is the spectral flooring factor.
In particular, the residual noise spectrum consists of peaks and valleys with random occurrences, and the overestimation factor α(m) and the spectral flooring factor β(m) have been introduced to reduce the spectral excursions.
In detail, the overestimation factor α(m) has been introduced to "overestimate" the noise spectrum, i.e., in other words the overestimation factor α(m) subtracts an overestimation of the noise over the whole spectrum, whereas the spectral flooring factor β(m) prevents the spectral lines of the estimate |{circumflex over (X)}k(m)|2 of the power spectrum of the clean speech from descending below a lower bound (β(m)|Yk(m)|2), thereby "filling-in" the deep valleys surrounding narrow peaks (from the enhanced spectrum). In fact, occasional negative estimates of the enhanced power spectrum can occur and in such cases, the negative spectral lines are floored to zero or to some minimal value (floor). Reducing the spectral excursions of noise peaks as compared to when the negative components are set to zero, reduces the amount of musical noise. Essentially by reinserting the broadband noise (noise floor), the remnants of the noise peaks are "masked" by neighboring components of comparable magnitude.
A variant of this technique in known as "Wiener Spectral Subtraction Technique", which is similar to the previous one but is derived from the optimal filter theory. The estimate |{circumflex over (X)}k(m)|2 of the power spectrum of the clean speech is the following:
                                                                                                      X                  ^                                k                                                          (                m                )                                                          2                =                  {                                                                                [                                                                                                                                                                Y                                  k                                                                                (                                  m                                  )                                                                                                                                        2                                                    -                                                                                α                                                                                (                                m                                )                                                                                                                                                                D                                      ^                                                                        k                                                                                (                                    m                                    )                                                                                                                                            2                                                                                ]                                            2                                                                                                                                                              Y                            k                                                                                (                            m                            )                                                                                                                      2                                                                                if                                                                                                                                                                Y                              k                                                                                (                              m                              )                                                                                                                                2                                                              -                                                                                α                                                              (                      m                      )                                                                                                                                                                D                              ^                                                        k                                                                                (                            m                            )                                                                                                                      2                                                        >                                                            β                                                                    (                        m                        )                                                                                                                                                              Y                            k                                                                                (                            m                            )                                                                                                                      2                                                                                β                                                                    (                        m                        )                                                                                                                                                              Y                            k                                                                                (                            m                            )                                                                                                                      2                                                                                otherwise                                                                                (        2        )
An improvement to the Spectral Subtraction Techniques is disclosed in V. Schless, F. Class, SNR-Dependent flooring and noise overestimation for joint application of spectral subtraction and model combination, ICSLP 1998, which proposes to make the noise overestimation factor α(m) and the spectral flooring factor β(m) functions of the global signal-to-noise ratio SNR(m).
Spectral Attenuation Technique, instead, is based on the principle of suppressing the noise by applying a suppression rule, or a non-negative real-valued gain Gk, to each spectral line k of the magnitude spectrum |Yk(m)| of the noisy speech, in order to compute an estimate |{circumflex over (X)}k(m)| of the magnitude spectrum of the clean speech according to the following formula: |{circumflex over (X)}k(m)|=Gk(m)|Yk(m)|.
Many suppression rules have been proposed, and probably one of the most important rules is the so-called Ephraim-Malah spectral attenuation log rule, which is described in Y. Ephraim and D. Malah, Speech Enhancement Using a Minimum Min-Square Error Log-Spectral Amplitude Estimator, IEEE Transaction on Acoustics, Speech, and Signal Processing, Vol. ASSP-33, No. 2, pp. 443-445, 1985.
Ephraim-Malah gain Gk(m) is defined as:
                                          G            k                                          (            m            )                          =                                                            ξ                k                                                          (                m                )                                                    1              +                                                ξ                  k                                                                  (                  m                  )                                                                                exp                                      (                                                1                  2                                                                                ∫                    k                    ∞                                                                                ⅇ                                                  -                          t                                                                    t                                                                                ⅆ                      t                                                                                )                                                          (        3        )            where:                ξk(m) is a so-called a priori signal-to-noise ratio relating to the k-th spectral line and is defined as follows:
                                          ξ            k                                          (            m            )                          =                                                                                            X                  k                                                                  (                  m                  )                                                                    2                                                                                              D                  k                                                                  (                  m                  )                                                                    2                                              (        4        )                            vk(m) is defined as:
                                          v            k                                          (            m            )                          =                                                            ξ                k                                                          (                m                )                                                    1              +                                                ξ                  k                                                                  (                  m                  )                                                                                γ              k                                                  (              m              )                                                          (        5        )                            γk(m) is a so-called a posteriori signal-to-noise ratio relating to the k-th spectral line and is defined as follows:
                                          γ            k                                          (            m            )                          =                                                                                            Y                  k                                                                  (                  m                  )                                                                    2                                                                                              D                  k                                                                  (                  m                  )                                                                    2                                              (        6        )
Computation of the a posteriori signal-to-noise ratio γk(m) requires the knowledge of the power spectrum |Dk(m)|2 of the additive noise, which is not available. An estimate |{circumflex over (D)}k(m)|2 of the power spectrum of the additive noise can be obtained with a noise estimate as described in H. G. Hirsch, C. Ehrlicher, Noise Estimation Techniques for Robust Speech Recognition, ICASSP 1995, pp. 153-156.
Thus, an estimate {circumflex over (γ)}k(m) of the a posteriori signal-to-noise ratio may be computed as follows:
                                                        γ              ^                        k                                          (            m            )                          =                                                                                            Y                  k                                                                  (                  m                  )                                                                    2                                                                                                                  D                    ^                                    k                                                                  (                  m                  )                                                                    2                                              (        7        )
Computation of the a priori signal-to-noise ratio ξk(m) requires the knowledge of the power spectrum |Xk(m)|2 of the clean speech, which is not available. An estimate {circumflex over (ξ)}k(m) of the a priori signal-to-noise ratio can be computed by using a decision-directed approach as described in Y. Ephraim and D. Malah, Speech Enhancement Using a Minimum Mean-Square Error Short-Time Spectral Amplitude Estimator, IEEE Trans. Acoustic, Speech, and Signal Processing, Vol. ASSP-32, Mo. 6, pp. 1109-1121, 1984, and as follows:
                                                                        ξ                ^                            k                                                  (              m              )                                =                                                    η                                                  (                  m                  )                                                                                                                                                                X                          ^                                                k                                                                                (                                                  m                          -                          1                                                )                                                                                                  2                                                                                                                                                      D                          ^                                                k                                                                                (                                                  m                          -                          1                                                )                                                                                                  2                                                      +                                          [                                  1                  -                                      η                                                              (                      m                      )                                                                      ]                                                          max                                                  [                                      0                    ,                                                                                γ                            ^                                                    k                                                                                (                          m                          )                                                                    -                      1                                                        ]                                                                    ,                                                                η                                      (              m              )                                ∈                      [                          0              ,              1                        )                                              (        8        )            where η(m) is a weighting coefficient for appropriately weighting the two terms in the formula.
The Ephraim-Malah gain Gk(m) may then be computed as a function of the estimate {circumflex over (ξ)}k(m) of the a priori signal-to-noise ratio and of the estimate {circumflex over (γ)}k(m) of the a posteriori signal-to-noise ratio according to formula (3).
An application of the Spectral Attenuation Technique is disclosed in US-A-2002/0002455, which relates to a speech enhancement system receiving noisy speech characterized by a spectral amplitude spanning a plurality of frequency bins and producing enhanced speech by modifying the spectral amplitude of the noisy speech without affecting the phase thereof. In particular, the speech enhancement system includes a core estimator that applies to the noisy speech one of a first set of gains for each frequency bin; a noise adaptation module that segments the noisy speech into noise-only and signal-containing frames, maintains a current estimate of the noise spectrum and an estimate of the probability of signal absence in each frequency bin; and a signal-to-noise ratio estimator that measures a posteriori signal-to-noise ratio and estimates a priori signal-to-noise ratio based on the noise estimate. Each one of the first set of gains is based on a priori signal-to-noise ratio, as well as the probability of signal absence in each bin and a level of aggression of the speech enhancement. A soft decision module computes a second set of gains that is based on a posteriori signal-to-noise ratio and a priori signal-to-noise ratio, and the probability of signal absence in each frequency bin.
Another application of the Spectral Attenuation Techniques is disclosed in WO-A-01/52242, which relates to a multi-band spectral subtraction scheme which can be applied to a variety of speech communication systems, such as hearing aids, public address systems, teleconference systems, voice control systems, or speaker phones, and which comprises a multi band filter architecture, noise and signal power detection, and gain function for noise reduction. The gain function for noise reduction consists of a gain scale function and a maximum attenuation function providing a predetermined amount of gain as a function of signal-to-noise ratio and noise. The gain scale function is a three-segment piecewise linear function, and the three piecewise linear sections of the gain scale function include a first section providing maximum expansion up to a first knee point for maximum noise reduction, a second section providing less expansion up to a second knee point for less noise reduction, and a third section providing minimum or no expansion for input signals with high signal-to-noise ratio to minimize distortion. The maximum attenuation function can either be a constant or equal to the estimated noise envelope. When used in hearing aid applications, the noise reduction gain function is combined with the hearing loss compensation gain function inherent to hearing aid processing.
Automatic speech recognition performed by using the known noise reduction methods described above is affected by some technical problems which prevents it from being really effective. In particular, Spectral Subtraction Technique and Wiener Spectral Subtraction Technique are affected by the so-called "musical noise", which is introduced in the power spectrum |Xk(m)|2 of the clean speech by the aforementioned flooring, according to which negative values are set to a flooring value β(m)|Yk(m)|2 in order to avoid occurrence of negative subtraction results. In particular, the flooring introduces discontinuities in the spectrum that are perceived as annoying musical noises and degrade the performances of an automatic speech recognition system.
Spectral Attenuation Technique implementing the Ephraim-Malah attenuation rule is a very good technique for the so-called speech enhancement, i.e., noise reduction for a human listener, but it introduces some spectral distortion on voice parts that are acceptable for humans but very critical for an automatic speech recognition system.

Noise reduction for automatic speech recognition


The present invention provides a one piece or unitary filter assembly for attachment to a waterline to remove chlorine and other substances from water. This unitary assembly provides a rechargeable or reusable filter assembly for use with hot water passing through a concentrated bed of 100% granulated or powdered zinc and includes a removable diverter/screen element to enable zinc to be added to or removed from an internal chamber formed therein. The preferred method of treating water utilizes 100% zinc filter media to react with or remove chlorine and other substances more efficiently from water, thereby allowing a greater volume of water to be treated, as well as the treatment of water at elevated temperatures. The pure zinc filtering media used has the added advantage of achieving a more efficient oxidation of chlorine while meeting current EPA standards.

1. Field of the Invention
This invention relates generally to treatment of fluids and more particularly to a device and method for the removal of unwanted materials, such as chlorine, from water.
2. Description of Related Art
Starting after the U.S. Civil War, the recognition and linking of macroscopic and microscopic pathogens to the aesthetic and health qualities of water resulted in the search for effective water disinfection and treatment procedures. Soon thereafter, chlorine was identified as a disinfecting agent. Towards the end of the 19th century, there were several recorded instances of the use of chlorine compounds for the disinfection of water and, with increasing experience, the effectiveness of chlorine treatment of water became more widely recognized and appreciated. The introduction of water chlorination, as a continuous process, occurred soon after the turn of the century. Currently, approximately 80% of all potable water systems in the U.S. contain chlorine as a disinfectant.
It is now known that chlorine passes across cell membranes and chemically bonds to amino acids, creating more complex chloro-compounds, disabling cellular protein synthesis, which in turn effectively destroys a micro-organism.
However, the treatment of water with chlorine is not without its drawbacks. Even in lower concentrations, such as originally used by commercial food processors and bottlers, chlorine creates an objectionable odor and taste. Also, as chlorine is added to water containing pathogenic microorganisms, the highly reactive chlorine combines with fatty acids and carbon fragments to form a variety of toxic compounds.
During the mid 1970's, monitoring efforts began to identify widespread toxic contamination of the water supplies in many parts of the world. In fact, epidemiological studies at the same time began to suggest a link between the ingestion of toxic chemicals in the water and elevated cancer mortality risks, as well as other diseases, such as arteriosclerosis, heart disease, anemia, high blood pressure, allergic reactions, and adverse conditions related to the drying and damaging of hair and skin.
Additional studies since the 70's indicate that chlorine and the compounds it forms in water can also be inhaled and absorbed through the skin by persons during bathing or showering. In fact, according to research presented at a meeting of the American Chemical Society in the 1980's, it was shown that "taking long hot showers is a health risk." In summary, this presentation stated that "taking showers, and to a lesser extent baths, lead to a greater exposure to toxic chemicals contained in water than does drinking the water. Due to the increased temperatures and surface area, the chemicals evaporate out of the hot water and are inhaled. They can also spread through the house and be inhaled by others. Householders can receive 6 to 100 times more of the chemicals by breathing the air around showers and baths than they would by drinking the water."
Different devices and methods for dechlorination of water have been used both at the point-of-entry ("POE") into a commercial, industrial or residential building, and the point-of-use ("POU") at the faucet, shower head or tap.
POE systems typically are in the form of an aerator, or a large organic or inorganic filtering media bed. Although applicable in some instances, these systems have potential problems, and have fallen under close scrutiny, due to the possibility of pathogenic reintroduction back into the water system, after the point of dechlorination. Because of this possibility, and the recent advancement in water treatment technology, POU water treatment systems have become widely accepted and are now primarily used in residential, and to a large degree, in commercial and industrial applications.
Both organic and inorganic filtering media are known for use in dechlorination. Carbon (organic) filtering media are used either alone, or in conjunction with other systems, such as reverse osmosis or distillation, or may be used with inorganic filtering media, such as cation/anion resins.
Carbon filtration comes about through the process of adsorption, which is dependent upon finite attachment sites located on the carbon filtering media, resulting in:
1.) A low volume capacity, typically measured or rated in (X) 100 gallons; and
2.) High temperature intolerance; a decrease in filtering efficiency as temperature increases up to a point where the filtration ceases and a releasing of filtered contamininates occurs (off-loading) back into the water, thereby producing a more contaminated water than if left unfiltered.
Some inorganic filtering media, such as cation/anion resins, have shortcomings similar to those of carbon, in that they have a very low volume capacity and become ineffective at higher temperatures.
Other known inorganic medias use a oxidation-reduction treatment method of the "electronegative cell potential type", based on the Voltaic or Galvanic cell, utilizing electrochemical principals. They are of a type that produce electricity as a result of spontaneous chemical change due to the electronegative potential created by the dissimilar metals used. This type of cell was first used by Alessandro Volta (1745-1827). He was able to generate electric current by stacking pieces of copper and zinc in salted water. The combination of copper and zinc, therefore, recreates the classic model of a chemically reactive cell, with the zinc and copper acting as electrodes. As the water passes through the "cell" the substances suspended in the water have a tendency to either be reduced or oxidized, thereby resulting in the molecular transformation of the substances. By using this type of method, distinct advantages exist. As the filtering media is typically metallic it possesses both a high volume capacity, measured or rated by (X) 1000 gallons, and a high temperature/high efficiency capacity.
One such prior art filter media is disclosed in U.S. Pat. No. 4,642,192, which discloses an "electronegative cell potential type" chlorine filter media, of the type discussed immediately above. The preferred media to filter out chlorine disclosed in this patent is brass (a mixture of copper and zinc). Although this patent mentions the use of zinc to remove chlorine, it points out in column 5, lines 17 through 23 thereof that although zinc is theoretically more spontaneous than copper, because it has a more positive potential, in actual practice it had been found that a zinc and copper alloy, such as brass, is more effective in the removal of dissolved chlorine than is either pure zinc or pure copper or a heterogeneous mixture thereof. Additionally, in lines 24 through 28 of this same column 5, it is recited that brass is also preferred from the viewpoint of chemical safety since it does not have the violent reactivity to aqueous fluids as do metals such as pure sodium, potassium, calcium and zinc. However, applicant's recent studies have demonstrated that the use of zinc alone, produces better results than a cooper/zinc mixture, thus coinciding with traditional inorganic chemistry theories. Also, since zinc is a transition element (copper is not) and not in the same chemical family, it does not have similar chemical properties, including reactivity, as does sodium, potassium (alkali metal elements) and calcium (alkaline earth metal element). It is a well known fact that zinc has an OSHA/MSDS and NFPD reactivity rating of #1. This is defined as: "Materials which in themselves are normally stable, but which can become unstable at elevated temperatures and pressures, or which may react with water with some release of energy, but not violently." In contrast to zinc, sodium, potassium and calcium are all given a reactivity rating of #2. This is defined as: "Materials which in themselves are normally unstable and readily undergo violent chemical change, but do not detonate. Also materials which may react violently with water or which may form potentially explosive mixtures with water. Additionally, this patent fails to take into account recent government studies and regulations, such as those from the Environmental Protection Agency (IIEPAII), which has set the maximum contaminant levels for copper in potable water as 5 times more stringent than for zinc. That is, copper's limit is one part per million (PPM), while zinc is much more tolerated, at 5 PPM.
The following disadvantages also exist with "electronegative cell potential type" filter medias:
1. The classic models either use acids as the fluid medium to activate the reaction, or when using a non-acidic fluid medium, electricity is driven across the cell.
If neither of these is used, the reaction in the cell is dependent on the relatively weak electrical potentials created by the difference of the standard reduction potentials (E.degree.values at 25 degrees C.) of each of the dissimilar materials used (as is the case for the "electronegative cell potential types").
In this connection, the disclosure in U.S. Pat. No. 4,642,192, starting at line 57 of column 4 and ending at line 28 in column 5 is incorporated herein, in its entirety, by this reference thereto. Therefore, for example, the difference in the reduction potentials between copper and zinc would be 1.10 volts, arrived at as follows: ##STR1## When using this method to oxidize chlorine, zinc will react more spontaneously than the copper. The copper will actually impede the reaction between zinc and chlorine, acting as an electronic buffer between the zinc and the chlorine, as follows: ##STR2##
Therefore, as shown, when 100% zinc combines with chlorine the reaction will be 3 times more spontaneous than a reaction of 100% copper with chlorine, and 1.5 times as spontaneous as the combination of a 50/50 mixture of copper and zinc with chlorine.
2. The "electronegative cell potential types" that use copper are further at risk of introducing copper into water, and exceeding the above EPA regulations for copper content in potable water.
Other prior art devices to remove chlorine from water supplies are known. These devices generally include filtering means for attachment in or to a waterline in a commercial, industrial, or residential setting, or to replace a faucet or shower head therein. By-pass means may be added to such devices, and valves may be switched or changed if it is desired to allow unfiltered water to exit from or travel around the filter means. In addition, as discussed above, different methods are used, and differing filtering media are held in these known devices to selectively remove, specific unwanted particles or materials from the water passing therethrough.
One type of filtering device now available for removing chlorine from water is disclosed in applicant's copending application, referred to above. The device disclosed therein is a compact filter assembly having a recessed inlet connected to the end of a waterline in a shower. The assembly contains a filtering media to filter out unwanted chlorine in the water passing through the filter and an adjacent internal baffle means to direct the flow of water more evenly through the filtering media. This filter assembly also includes internal placement and reinforcing means to properly locate the internal baffle means and to strengthen the two parts of the filter housing. A water shut-off means and a compact shower head may also be added after the filter media, and does not greatly increase the size of this compact filter means.
U.S. Pat. No. 2,582,388, discloses another prior art water filter, for insertion into a waterline, having two parts threaded together to form a shell or housing, having a plurality of screens held in an inlet to and outlet from the interior thereof. Layers of activated charcoal, separated by a layer of silica and screens are arranged in the shell to filter water passing through the shell.
U.S. Pat. No. 3,760,951, incorporates U.S. Pat. No. 2,582,388 therein by reference, and discloses a similar water filter for insertion into a waterline by means of quick-disconnect bayonet fittings that allow the filter to be easily removed for cleaning or replacement.
U.S. Pat. No. 3,780,869, discloses a water filter, for insertion into a waterline, having a plurality of compartments with multiple filtering elements of sheep's wool therein. The filter includes two separate body parts which are held together by threaded portions that allow the body to be taken apart and put back together to replace or clean the multiple filter elements contained therein. The filter also includes a valve for shifting between filter and non-filter positions.
U.S. Pat. No. 3,822,018, discloses a water filter, for insertion into a waterline, having two hemispherical sections joined together by threaded portions. The filter has a plurality of cylindrical filter elements annularly arranged therein containing natural wool, charcoal, cork and the like, and includes a valve for directing water through the filter elements or for directing water through the device, unfiltered.
U.S. Pat. No. 4,107,046, discloses a filter cartridge for an internally by-passable water purifier apparatus. The apparatus includes valve means for directing water through the filter cartridge, which contains granulated carbon mixed with a silver zeolite, and may be sandwiched between fibrous sheets of material, such as felt, before it exits the apparatus, and another valve means for directing water to the outlet of the apparatus along a path that by-passes the filter cartridge.
U.S. Pat. No. 4,172,796, discloses a water faucet having a water purification or filtering means, made from activated carbon, or carbon with oligodynamic silver, formed therein. Valve means are provided for selecting the flow of water therethrough to either discharge filtered or unfiltered water.
U.S. Pat. No. 4,504,389, discloses a water faucet having a separate housing containing a removable cartridge or filter element made from various stages of polyethylene and activated carbon particles therein, and valve means for selecting whether the faucet provides filtered or unfiltered water. The filter cartridge is replaceable by removing a cap covering the separate housing holding the cartridge, lifting out the old cartridge, and inserting a new cartridge.
U.S. Pat. No. 5,008,011, discloses a shower dechlorinator fabricated in the form of a short cylindrical filter housing having two separate end caps with inlet and outlet means for attachment between the outlet pipe for a shower and a shower head. The filter housing is filled with granulated or randomly oriented fibrous material in the form of a copper/zinc metal alloy. This patent is limited in its disclosure to the specific shape of the filter housing and the copper/zinc metal alloy filter media described therein. The shape and size of the filter housing is akin to that of a so-called "pipe bomb", and the copper/zinc metal alloy is similar, if not identical, to that disclosed in U.S. Pat. No. 4,642,192 discussed above, and suffers from the same problems discussed in connection with this patent.
While the foregoing prior art devices, filter media and methods provide improved filtration of water passing through them, they are not adapted to meet the health and safety standards of today, nor do they meet the requirements, such as in baths or showers, that larger volumes of heated water having increased amounts of unwanted chlorine therein be safely filtered out. Furthermore, while the above-mentioned prior art provide some limited improvements in the filtering art, there remains the need in the art for a filter assembly that provides maximum strength, as well as the most efficient method of filtering out unwanted materials, such as chlorine, while at the same time meeting the more stringent health and safety regulations of local communities and such governmental agencies as the EPA.


The various embodiments described herein include memory dies and methods for memory die communications. In one aspect, a method is performed at a first memory die with a plurality of memory banks and a plurality of contacts. The method includes: (1) coupling a first memory bank of the plurality of memory banks to a second memory die via the plurality of contacts; (2) transmitting data between the first memory bank and the second memory die via the plurality of contacts; and (3) receiving a control signal to couple a second memory bank of the plurality of memory banks to the second memory die. The method further includes, in response to receiving the control signal, coupling the second memory bank to the second memory die via the plurality of contacts; and transmitting data between the second memory bank and the second memory die via the plurality of contacts.

Higher density electronic chips can be achieved by specialized electronic packages where multiple integrated circuits (ICs) are packaged into a multi-chip module (MCM). Recent MCM technologies allow multiple semiconductor dies to be packaged as a vertical stack (i.e., a multi-die stack or a multi-chip stack) formed on a substrate. The dies in multi-die stack may include electronic circuitry such as memory banks (e.g., dynamic random access memory (DRAM)), memory controllers, central processing unit (CPU), etc. The dies in the multi-die stack can be interconnected by various forms of contacts such as through-silicon vias (TSVs) or solder bumps. Configuring electronic circuits and providing connections from the electronic circuits to interconnect contacts (e.g., TSVs or solder bumps) on a die in the multi-die stack becomes more challenging as the density of contacts on the die increases (e.g., due to enhanced complexity of the electronic circuits and/or reduced minimum feature size). Moreover, the efficiency and speed of existing multi-die stacks is reduced by configurations of electronic circuits that include large numbers of contacts and extensive circuitry.

Multi-die DRAM banks arrangement and wiring


A process for producing a finely cellular polyurethane foam by mixing a first ingredient comprising an isocyanate compound and a second ingredient comprising a compound containing an active hydrogen group, characterized by comprising adding a nonionic silicone surfactant containing no hydroxyl group to at least one of the first ingredient and the second ingredient in an amount of 0.1 to 5 wt %, excluding 5 wt %, based on the total amount of the first ingredient and the second ingredient, subsequently agitating the surfactant containing ingredient together with an unreactive gas, which has no reactivity to isocyanate group or active hydrogen group, to disperse the unreactive gas as fine bubbles to prepare a bubble dispersion and then mixing the bubble dispersion with the remaining ingredient to cure the resultant mixture and forming finely cellular structure into the resultant polyurethane foam by the fine bubbles of the bubble dispersion.

1. Field of the Invention
The present invention relates to a process for producing polyurethane foam having uniform fine cells. A polyurethane foam obtained by the process of the present invention may be suitably used as polishing materials for resins, glass, lens, rock crystals, and silicon for producing semiconductors, electronic substrates, optical substrates etc. Especially a polyurethane foam of the present invention, which is cut as necessary, is suitably used as polishing sheets for CMP.
2. Description of the Related Art
As technology for producing a polyurethane foam, a method in which adding organic solvents having low boiling point, such as fluorocarbons and methylene chloride, into an ingredient composition for foaming and dispersing, and then foaming by polymerization heat vaporization; a method in which adding water into a ingredient composition for foaming and dispersing, and then foaming with carbon dioxide gas generated by a reaction of isocyanate groups and water, are well known. In a foam obtained by these methods, diameter of foamed cells (diameter of cells) has a minimum of 100 μm as an average, it is difficult to obtain a foam having more finely and uniform cells.
Following methods are known as a process for producing a polyurethane foam that has fine cells.    (1) A method that after fine-particles soluble in a solvent are dispersed into polyurethane polymer and are molded into a predetermined form, the molded body is immersed in a solvent that dissolves the fine-particles but does not dissolve the polyurethane polymer, the fine-particles are removed by dissolving to obtain a porous polyurethane resin, that is, polyurethane foam.    (2) A method that finely hollow foamed materials are dispersed in an ingredient composition forming polyurethane.
However, in a case where the above-mentioned method (1) is used, since much amount solvent is required, and treatment for the solvent containing material forming fine-particles is indispensable, high cost naturally occurs. Moreover only open-celled foam may be obtained, the foam obtained may not be used for usage where rigidity is needed, usage is limited. Besides, there is also a problem that a dissolving process and a solvent drying process are also needed, and a long time is needed in order to prepare a very thick molded body.
On the other hand, in the method of (2), since a finely hollow foam has a strong tendency to be floated up in a polyurethane forming solution based on a difference of density, a uniform foam is difficult to be produced. Besides, the finely hollow foam is comparatively expensive, and further since the raw material of the finely hollow foam is remained in the foam, there is a possible problem of inducing damage on a cutting edge in the case where the foam is cut. And the hollows fine-particles are scattered easily and then great costs are needed for facilities of working environmental maintenance.
By the way, a polyurethane foam is applied as a polishing sheet for producing silicon for semiconductors and the like, and producing an electronic substrates. In polishing sheet, highly precise polishing properties are required based on higher density of a formed circuit. Depend on types of particles and size of particles that are contained in polishing slurry used in polishing, a hardness of polishing sheet (polyurethane foam) and the like needs to be matched to those characteristics. For example, ceria derived slurry has a larger particle size than silica derived slurry, and when ceria derived slurry is used as polishing slurry, higher hardness is needed than silica derived slurry.
An object of the present invention is to provide a process for producing a polyurethane foam that have uniform fine cells and higher hardness than ones having the same density can be produced without using a chemically reactive blowing agent such as water, vaporizable expandable blowing agent such as fluorocarbon, or other substance such as a finely particulate hollow foam or solvent soluble substance.
Furthermore, another object of the present invention is to provide a polishing sheet adapted to polishing slurry by using polyurethane foam obtained by the above-mentioned process.

This patent is subject to a terminal disclaimer.


A thermally assisted magnetic head has a medium-facing surface facing a medium, and comprises: a waveguide an end face of which is exposed in the medium-facing surface; an electroconductive near-field light generator plate disposed on a medium-facing surface of the waveguide so that a principal face thereof faces the medium; and an electroconductive near-field light scatter plate disposed on the medium-facing surface of the thermally assisted magnetic head so that a principal face thereof faces the medium; when viewed from a direction perpendicular to the medium-facing surface, the near-field light generator plate has a cusp portion at an end; when viewed from the direction perpendicular to the medium-facing surface, the near-field light scatter plate is arranged along the other end opposite to the cusp portion of the near-field light generator plate; when viewed from the direction perpendicular to the medium-facing surface, a width of the near-field light scatter plate in a first direction perpendicular to a direction connecting the cusp portion and the other end of the near-field light generator plate is larger than a width in the first direction of the near-field light generator plate.

1. Field of the Invention
The present invention relates to a thermally assisted magnetic head for writing of signals by thermally assisted magnetic recording, and to a head gimbal assembly (HGA) with this thermally assisted magnetic head, and a hard disk drive with this HGA.
2. Related Background Art
As the recording density of the hard disk drive increases, further improvement is demanded in the performance of the thin film magnetic head. In order to increase the recording density, a recording medium is made of a magnetic material with large Ku and the so-called thermally assisted magnetic recording is proposed as a method of applying heat to the recording medium right before application of a writing magnetic field to lower the coercivity of the magnetic material, and then performing writing.
As examples of such thermally-assisted magnetic head recording apparatus, Japanese Patent Application Laid-Open No. 2001-255254, Japanese Patent Application Laid-Open No. 2003-114184 and T. Matsumoto et al., Near-Field Optical Probe with A Beaked Metallic Plate for Thermally Assisted Magnetic Recording, pp. 6-7, MORIS2006 WORKSHOP Technical Digest, Jun. 6-8, 2003 disclose the thermally-assisted magnetic heads in which an electroconductive near-field light generator plate of a plate shape is disposed on a medium-facing surface and in which light is guided onto the near-field light generator plate from the back side to generate near-field light. A pointed cusp portion is formed at an end of the near-field light generator plate and the near-field light is emitted mainly from this cusp portion.


An x-ray acquisition apparatus has a spatially adjustable x-ray detector, a spatially adjustable x-ray source, and a control unit with which the x-ray source can be aligned relative to the x-ray detector. The control unit accounts for the position of radio-opaque objects in the examination room and, before an x-ray acquisition, outputs a signal is a radio-opaque object is located in the beam path of the x-ray source.

1. Field of the Invention
The present invention concerns an x-ray acquisition apparatus of the type having a spatially adjustable x-ray detector, a spatially adjustable x-ray source, and a control unit with which the x-ray source can be aligned to the x-ray detector.
2. Description of the Prior Art
An x-ray acquisition apparatus of this type is known from DE 196 11 705 B4. In the x-ray acquisition apparatus described there, the x-ray source can be aligned relative to the x-ray detector that can be adjusted three-dimensionally in space. This known x-ray acquisition apparatus does not take into account the position of radio-opaque objects that are located in the room (such as perhaps a patient bed that may be located in the beam path). After every positioning of the x-ray detector, therefore, the user must ascertain whether a radio-opaque object is located in the beam path. This assessment represents an additional time expenditure and is not always reliably possible, so that incorrect (flawed) exposures can be created.

X-ray apparatus with component positioning coordinated with radio-opaque objects in examination room


The present invention includes a method and system for creating a price-forecasting tool for a commodity. The method and system comprise providing price data and industry capacity utilization data related to the commodity, and establishing the price-forecasting tool based on a statistical relationship between the price data and the industry capacity utilization data. A method of doing business is disclosed comprising creating a price forecasting tool based on a statistical relationship between price data and industry capacity utilization data of the commodity, and utilizing the price forecasting tool to generate a plurality of scenario prices for the commodity for a plurality of forecast horizons. A computer program product is disclosed for creating a price forecasting tool comprising a computer usable medium having computer readable program means for causing a computer to perform the steps of providing price data and industry capacity utilization data related to the commodity, and establishing the price forecasting tool based on a statistical relationship between the price data and the industry capacity utilization data.

The present invention relates generally to price modeling and particularly to a method and system for creating a price-forecasting tool.
In today's financial markets, the use of financial instruments known as "derivatives" have exponentially grown and is now common-place. A derivative is an investment vehicle with a value that is based on the value of another security or underlying asset. That is, a derivative is essentially a financial instrument that is derived from the future movement of something that cannot be predicted with certainty. By the late 1990's the Office of the Comptroller of the Currency estimates that commercial banks in the United States alone, held over twenty trillion dollars worth of derivative-based assets. Common examples of derivatives include futures contracts, forward contracts, options, and swaps.
The relationship between the value of a derivative and the underlying asset is not linear and can be very complex. Economists have developed pricing models in order to valuate certain types of derivatives. At the core of various derivative-pricing models are assumptions about how the price of the underlying asset (like a stock) may change over time. These pricing models provide probability distributions that describe the possible states of prices at different points in the future. Prices are generally modeled as a stochastic process, in which the values change over time in an uncertain manner. A particular type of stochastic process is the Markov process, where only the present state of the process (e.g., the current stock price) is relevant for predicting the future. The past history of the process is irrelevant.
A particular type of Markov process typically used to model prices is geometric Brownian motion (GBM). GBM, which is the basis of the vast majority of derivative pricing models, makes two key assumptions:                1. Price changes over small time intervals are independent, and therefore longer-term forecasts can be generated by repeatedly simulating small incremental changes in prices.        2. The distribution of future predicted prices is log-normal (LN).
While there are many variations on the GBM approach to modeling asset or commodity prices, they all are fundamentally constrained by the two assumptions listed above. Consequently, while these approaches to modeling price may fit well in efficient, exchange-traded markets, they do not fit well in markets for commodities that are not traded on exchanges. Such markets are typically dominated by a handful of big buyers and big suppliers who negotiate prices directly. These markets tend to move not in a random fashion, as the "small independent intervals" assumption would suggest, but rather in cycles lasting from 6 months to several years. Within each cycle, periodically negotiated contract prices continue on a rising or falling trend, without deviation, until the market suddenly "turns" and prices head in the other direction. Therefore, the assumption that price changes over different horizons can all be modeled using the same model of changes over small, independent intervals is not good.
A co-pending patent application entitled "A Method and System For Creating A Price Forecasting Tool," naming the applicant as a co-inventor (HPP number 200206487-1) (referred to herein as the "Co-pending Patent Application") provides a method and system for forecasting prices of commodities by building a statistical model of price forecasts for each desired forecast horizon. The method of the Co-pending Patent Application involves first receiving historical data related to a commodity, defining a long-run average price trend based on the received historical data and creating a price forecasting tool based on the long-run average price trend. The price forecasting tool is capable of taking into account a market momentum of the commodity in order to generate a plurality of scenario prices of the commodity for a plurality of forecast horizons.
Although the Co-pending Patent Application provides a way to forecast pricing using price trends and short-term price momentum, other factors are involved in the complex market milieu that should be considered in order to more finely tune the price-forecasting method and system to reduce error. Accordingly, what is needed is a method and system for forecasting future commodity pricing that includes important market variables besides pricing. The method and system should be simple, cost effective and capable of being easily adapted to existing technology. The present invention addresses these needs.

Method and system for forecasting commodity prices using capacity utilization data

Hewlett-Packard Development Company, L.P.


In a raised-image printing process, a plate construction includes a plate portion with an upper printing surface for printing an image on a substrate, the image including areas of greater ink coverage and areas of lesser ink coverage. Regions of greater and lesser stiffness are incorporated in the construction such that greater stiffness occurs under image areas of greater ink coverage, and lesser stiffness occurs under areas of lesser ink coverage.

In accordance with the general terminology utilized in the printing industry, the word "letterpress" refers to a printing procedure in which the locations on the printing plate where ink is to be deposited are raised with respect to areas where ink is not to be deposited. Within the general designation of letterpress printing, two distinguishable forms can be identified. The first typically utilizes a relatively stiff printing plate (i.e. employing a material of relatively high stiffness), commonly referred to in the industry as a "hard" plate. "Hard" plate letterpress systems typically employ an impression roll with a compliant coating and one or more form cylinder(s) also with compliant coating(s). The form cylinder may be either directly inked from a well, or remotely inked through a series of rollers. The ink on the form cylinder is transferred to the inking locations on the "hard" plate which is mounted to the plate cylinder. The web or sheet of substrate to be printed is entrained between the impression cylinder and the plate cylinder. With a "hard" plate, the impression cylinder must be relatively less stiff, in order to avoid damage due to mechanical interference, and/or to improve the evenness of ink transfer from the printing plate to the substrate to be printed.
In this specification, the quality of "stiffness" means the resistance of a material to deformation under a given force. For example, if equal thicknesses of two different materials were placed on a hard surface, and a given weight over a given area were impressed upon each of the materials in order to deform or "pinch" the material, the material with the greater stiffness would yield less than the material with the lesser stiffness.
The second letterpress category utilizes a printing plate (commonly referred to in the industry as a "soft" plate) whose stiffness is relatively lower, i.e. the raised areas which are to be inked and then transfer the ink to the substrate are relatively less stiff with respect to the relatively more stiff form cylinder(s) and relatively more stiff impression roll (frequently steel).
The term "flexographic" is often utilized to refer to the second letterpress system described immediately above, in which a less stiff plate is used e other two rollers being relatively more stiff.
In the raised plate printing method the printing plates are normally made with as uniform a total thickness as is possible.
The printing industry generally recognizes certain inherent problems relating to the raised plate printing method using a soft plate of uniform resilience. One of these problems relates to the degree to which the printing surface of the plate is urged against the substrate, depending upon the area of coverage of the ink. It is known that the degree to which a plate surface is urged against the substrate is preferably less for the less covered areas, and more for the more covered areas. The "urging" comes about due to the squeezing or pinching of the soft plate between the substrate and the plate cylinder. When the area less covered includes tiny dots due to the four-colour separation process, the dots are printed by an upstanding cone having on top a flat portion which accepts ink and prints the dot. It is found generally that the amount of plate squeezing necessary to properly print solid-ink areas is too great to allow correct printing of the dotted areas, because the conical support below the inked surface creates excessive contact pressure which in turn tends to expel ink from the space between the paper and the raised dot on the plate, thus forming a ring or doughnut of solid ink around a central zone of inadequate ink coverage. On the other hand, if the degree of squeezing between the plate and the impression roll is reduced to a level which allows a good printing of the dot, it is found that areas of solid ink are inadequately printed, i.e. the ink is not fully and/or properly transferred to the substrate.
It is known to provide, for use with a printing plate, a "make ready" plate which corresponds to the plate in the sense that the "make ready" plate has an increased thickness in the regions corresponding to the more solid ink printing, and a gradually decreasing thickness in proportion to the degree of ink coverage in other regions of the plate. Areas of low ink coverage will include locations where fine copy appears. The "make ready" is positioned under the plate with corresponding areas matched, so that all solid regions will tend to be urged more strongly against the substrate (i.e., squeezed more) than are the areas which are only partially ink covered. It is understood that this process works to some extent, but not fully. It involves considerable extra expense to fabricate the "make ready" sheet, and it complicates the process of affixing the plate to the plate cylinder.
Relative to the affixing of the plate to the plate cylinder, where a plate of relatively low stiffness is utilized without the "make ready plate", it is typical in the industry to use a sheet of two-sided adhesive tape between the plate and the cylinder. Such tape may be very compliant (referred to in the trade as "cushion tape"), incorporating a layer of open or closed cell foam which is usually very low in stiffness. It is also known to use relatively stiff or non-compliant tape. It has been found that, when a low-stiffness tape is used to secure the plate to the plate cylinder, the plate-to-substrate contact pressure drops off too greatly in the locations of high ink coverage (area-wise), while the contact pressure between plate and substrate in the locations of relatively low ink coverage (area-wise) tends to allow more acceptable printing as the dots become smaller. The low-ink coverage areas are referred to as the highlight areas of the four colour printing process. Conversely, when a stiff tape is used, the dot areas extrude ink outwardly to a larger diameter than originally intended, and the locations of heavy ink coverage (area-wise) usually print relatively properly.
Among the prior art known to the applicant, U.S. Pat. 3,103,168, issued Sep. 10, 1963 to Braznell et al, exemplifies the difficulties encountered when using a plate component with a varying thickness. Because of this variation in thickness, it tends to be difficult if not impossible to ensure that the plate achieves a proper "fit" around the cylinder. In the four-colour separation process, each combination of printing plate and make-ready, as taught by Braznell et al, will have a different configuration, with the raised parts varying in height (thickness) between the different colors. For example, if the picture to be reproduced has a lot of yellow, the yellow plate would be effectively thickened up substantially compared to the plate for a colour which is less in evidence than the yellow. This would certainly mean that the four printings would likely fail to coincide or "fit" together. Another problem is that of "register", which has to do with keeping the web at the right "repeat length" with respect to the plate cylinder. What happens is that, because the plate (the upper surface of the plate) is digging into the web, and into the impression roll if it is a soft one, the web is actually driven by the plate, particularly where the thickness of the plate is excessive. Thus the web can be (and very frequently is) forced out of proper registry by overly thick plate regions.
Another patent of some interest is U.S. Pat. No. 3,169,066, issued Feb. 9, 1965 to Hoerner. Hoerner describes a process for sensitizing a polymeric body such that exposure to light, through either a positive or negative of a picture, initiates either a selective softening process (to create areas that can be abraded away) or a hardening process (wherein the non-exposed areas can be abraded away). In particular, Hoerner describes the possibility of using transparent blocks for making a printing plate, the transparent blocks allowing the light to pass directly through from one surface to the other, thus producing a reverse image on the bottom surface. Hoerner refers to this bottom image briefly as a "make-ready". However, in actual fact Hoerner does not change the stiffness of the various regions or columns affected by the light, in such a way as to vary the stiffness per unit printing area. In other words, even though Horner provides, for each "cone" to print a dot of colour, a reverse "cone" on the other surface, the column of plastic between the upper conical shape and the lower conical shape is not stiffer or less stiff than the plastic material occupying a similar cylinder in a solid-ink region.
One of the prerequisites for the carrying out of the present invention is a polymer which, upon exposure to suitable radiation (such as light), will undergo graduated hardening or graduated softening. A patent of interest in this area is U.S. Pat No. 3,549,366, issued Dec. 22, 1970 to Margerum, the specification of which is hereby incorporated by reference. The Margerum patent discloses a method of effecting optical hardening of photosensitized acrylamide compositions. The patentee indicates that the images are initially illuminated and projected or cast upon the prepared photosensitive acrylamide composition by visible radiation, this being followed by uniform illumination of the composition with visible light, and subsequent uniform ultraviolet radiation hardening.
Another patent of interest is U.S. Pat. No. 3,137,633, issued Jun. 16, 1964 to Kline. Kline discloses the discovery that the density of cross-linking in polyethylene or silicones depends to some extent on the energy absorbed per gram. The disclosure of this patent is hereby incorporated by reference.
Yet another patent of interest is U.S. Pat. No. 4,790,919, issued Dec. 13, 1988 to Baylor, Jr. Although directed to the preparation of electrophoresis gel material, the patent does discuss the photoinitiation of polymerization, and further discusses varying the intensity of light in order to adjust the degree of polymerization. The disclosure of this patent is hereby incorporated herein by reference.
A further patent of interest is U.S. Pat. No. 4,557,994, issued Dec. 10, 1985 to Nagano et al, the specification of which hereby incorporated herein by reference. This patent discloses a printing plate which is light-sensitive, and lists a number of suitable materials.
A still further patent of interest is U.S. 3,798,035, issued Mar. 19, 1974 to Varga et al, the disclosure of which is hereby incorporated herein by reference. Varga et al teach that the extent of crosslinking in a photopolymer is dependent on the combination of intensity and duration of radiation. This is inferred from the admission that the extent of cross-linking diminishes as depth from the exposed surface increases, and it is clear that the intensity of the radiation would decrease with increasing distance from the exposed surface.
A further patent of interest is U.S. Pat. No. 3,874,376, issued Apr. 1, 1975 to Dart et al, the disclosure of which is hereby incorporated herein by reference. Dart et al indicate that the degree of polymerization of a photopolymer depends upon the intensity of the visible light used.
In view of the foregoing discussion, it is an object of one aspect of this invention to facilitate optimum printing with a raised plate without having to vary the distance from the printing surface to the plate cylinder, wherein the urging of the plate surface against the substrate under the more solidly inked areas of the plate is greater than under the partially inked areas. Preferably, the urging varies continuously such that it is roughly proportional to the degree of ink coverage. Alternatively, the variation may be in discrete steps, again roughly proportional to the degree of ink coverage.
More particularly, this invention provides, for use in a raised image printing process employing a plate support, an improved plate construction comprising:
a flexible plate portion having an upper printing surface for printing an image on a substrate, the image including areas of greater ink coverage and areas of lesser ink coverage,
and means incorporated integrally into the plate portion for providing graduated regions of greater and less resistance to deformation below said upper printing surface, said means affecting the degree to which the surface is urged against the substrate with greater resistance to deformation occurring under image areas of greater ink coverage, and lesser resistance to deformation occurring under areas of lesser ink coverage, the plate portion having a uniform thickness, whereby said upper printing surface is uniformly spaced above the plate support.
Additionally, this invention provides a method of printing using a raised image printing process, the method comprising the steps:
providing a support surface;
providing a plate portion which has an upper printing surface for printing an image;
providing a support surface;
providing a plate portion which has an upper printing surface for printing an image;
securing said plate portion to said support surface such that said upper printing surface is at a uniform spacing from said support surface;
providing graduated regions of differing resistance to deformation integrally within said plate portion without altering said uniform spacing, such that a greater degree of resistance to deformation is provided under image areas of greater ink coverage, and a lesser degree of resistance to deformation is provided under image areas of less ink coverage; and
printing an image utilizing said upper printing surface.

Raised image plate construction with regions of varying stiffness in the image areas