A determination device selects a determination area included in a captured image acquired by an imaging data acquisition device, extracts a determination image of a preset target color from the selected determination area, binarizes gradation data of the target color in pixel regions constituting the extracted determination image by using a binarization threshold suitable for each determination area to acquire binarized reference binary data of the determination image, converts the gradation data of the target color in the pixel regions constituting the extracted determination image with respect to a dark portion of the determination image to acquire converted gradation data, binarizes the acquired converted gradation data by using the binarization threshold to acquire comparison binary data, and acquires, based on comparing the reference binary data with the comparison binary data, a determination value for determining a printing method used to produce a printed surface of a printed product.

A determination device selects a determination area included in a captured image acquired by an imaging data acquisition device, extracts a determination image of a preset target color from the selected determination area, binarizes gradation data of the target color in pixel regions constituting the extracted determination image by using a binarization threshold suitable for each determination area to acquire binarized reference binary data of the determination image, converts the gradation data of the target color in the pixel regions constituting the extracted determination image with respect to a dark portion of the determination image to acquire converted gradation data, binarizes the acquired converted gradation data by using the binarization threshold to acquire comparison binary data, and acquires, based on comparing the reference binary data with the comparison binary data, a determination value for determining a printing method used to produce a printed surface of a printed product.

A payment card includes hidden features (e.g., textual messages, graphics, emphasis features associated with conspicuous features of the payment card, or the like) undiscernible under only visible light, but discernable under ultraviolet light. The hidden features can be incorporated into multiple layers of a side of the payment card and can be present with different transparencies, different colors, and different persistence.

A composite pigment includes first and second cholesteric liquid crystal pigments. The first cholesteric liquid crystal pigment has a center wavelength of a selective reflection band within a wavelength range of 400 nm or more and 800 nm or less and a selective reflection bandwidth of 150 nm or less. The second cholesteric liquid crystal pigment has a selective reflection bandwidth of 200 nm or more within a wavelength range of 400 nm or more and 800 nm or less. The selective reflection band of the first cholesteric liquid crystal pigment and a selective reflection band of the second cholesteric liquid crystal pigment at least partially overlap with each other. A containing amount of the first cholesteric liquid crystal pigment relative to a total amount of the first and second cholesteric liquid crystal pigments is more than 30% by weight and 80% by weight or less.

A composite pigment includes first and second cholesteric liquid crystal pigments. The first cholesteric liquid crystal pigment has a center wavelength of a selective reflection band within a wavelength range of 400 nm or more and 800 nm or less and a selective reflection bandwidth of 150 nm or less. The second cholesteric liquid crystal pigment has a selective reflection bandwidth of 200 nm or more within a wavelength range of 400 nm or more and 800 nm or less. The selective reflection band of the first cholesteric liquid crystal pigment and a selective reflection band of the second cholesteric liquid crystal pigment at least partially overlap with each other. A containing amount of the first cholesteric liquid crystal pigment relative to a total amount of the first and second cholesteric liquid crystal pigments is more than 30% by weight and 80% by weight or less.

A payment card includes hidden features (e.g., textual messages, graphics, emphasis features associated with conspicuous features of the payment card, or the like) undiscernible under only visible light, but discernable under ultraviolet light. The hidden features can be incorporated into multiple layers of a side of the payment card and can be present at different transparencies. The hidden features, applied during manufacturing, can be i) selected (e.g., randomly or sequentially) from an available hidden features list; ii) supplied by user input; and/or iii) selected based on a user's previous hidden feature(s) (e.g., the same as or different from the previous hidden feature). A quality check can include comparing an image of the payment card illuminated under ultraviolet light with the selected hidden feature(s).

A physical payment card includes hidden features (e.g., textual messages, graphics, emphasis features associated with conspicuous features of the payment card, or the like) undiscernible under only visible light, but discernable under ultraviolet light. A digital version of the physical card can be established on a user device. During setup, the user device can receive data regarding the hidden features that are associated with the physical card. Under a normal state, the user device can display the digital card without displaying the hidden features. However, upon activation (e.g., when the digital card is used, when the physical card is used, when the physical card is in sufficient proximity, or the like), the user device can display the hidden features on the digital card.

A banknote monitoring apparatus includes a reception section that receives information including a serial number from each of a plurality of banknote processing apparatuses processing a banknote with the serial number; and a control section that determines whether a specification of the banknote has been changed based on an identification rate of the serial number obtainable with the information received.

A banknote monitoring apparatus includes a reception section that receives information including a serial number from each of a plurality of banknote processing apparatuses processing a banknote with the serial number; and a control section that determines whether a specification of the banknote has been changed based on an identification rate of the serial number obtainable with the information received.

A method including correcting output of an image sensor unit based on correction information of the image sensor unit that captures and discriminates a paper sheet. A apparatus includes an image sensor unit which includes an image capturing element that captures a banknote so as to discriminate the banknote, a controller that controls the image sensor unit, and a first attachment part, to which the image sensor unit is attached to be detachable, and which includes a connection terminal that connects the image sensor unit and the controller with each other, and which is arranged in a conveyance path for conveying the banknote.