Spot-color ink refers to a pre-mixed specific color ink, such as fluorescent yellow, Pearl blue, metal gold and silver ink, which is not a CMYK four-color mix, which means precise color.

專色油墨是指一種預先混合好的特定彩色油墨，如熒光黃色、珍珠藍色、金屬金銀色油墨等，它不是CMYK四色混合出來的，套色意味著精確的顏色。它有以下四個特性：

Spot-color ink refers to a pre-mixed specific color ink, such as fluorescent yellow, Pearl blue, metal gold and silver ink, which is not a CMYK four-color mix, which means precise color. It has the following four characteristics:

1   精確性。

1. Accuracy.

每一種套色都有其自身固定的色相，所以它可以保證印刷中顏色的精確性，從而在很大水平上處理了顏色傳送精確性的問題；

Each color set has its own fixed hue, so it can ensure the accuracy of color in printing, thus dealing with the problem of color transmission accuracy to a large extent.

2   實地性。

2. Fieldwork.

專色普通用實地色定義顏色，而無論這種顏色有多淺。當然，也能夠給專色加網（Tint），以呈現專色的恣意深淡色調；

Spot colours are usually defined by solid colours, no matter how light they are. Of course, it can also screen the spot color (Tint) to show the arbitrary dark tone of the spot color.

3   不透明性。

3. Opacity.

專色油墨是一種掩蓋性質的油墨，它是不透明的，能夠停止實地的掩蓋；

Spot-color ink is a kind of cover-up ink, which is opaque and can stop the cover-up on the spot.

4   表現色域寬。

4. Wide gamut.

套色色庫存中的顏色色域很寬，超越了RGB的表現色域，更不用說CMYK顏色空間了，所以，有很大一局部顏色是用CMYK四色印刷油墨無法呈現的。

The color gamut in the register stock is very wide, beyond the performance gamut of RGB, let alone CMYK color space, so a large part of the color can not be rendered with CMYK four-color printing ink.

印前運用專色應留意的一些問題

Some Problems Should Be Noticed in the Use of Spot Color before Printing

1   專色顏色稱號的統一。

1. Unification of spot color designations.

在不同的軟件中，關于完整相同的兩種套色，其稱號可能會有所不同。如FreeHand把PANIONEI IF5 命名為PANTIONE 1F5CVC。這樣一來，當把FreeHand圖形對象置入PageMaker中排版時，同樣的顏色就會有三種稱號，分色輸出時就會產生三塊印版，形成輸出錯誤。

In different software, there may be different titles for the same two sets of colors. For example, FreeHand named PANIONEI IF5 PANTIONE 1F5CVC. In this way, when FreeHand graphics objects are placed in PageMaker typesetting, there will be three designations for the same color, and three plates will be produced when the color separation output, resulting in output errors.

所以，假如數據文件需求在兩種以上的軟件中運用，在整合后的分色輸出前，一定要留意：必需統一相同專色的運用稱號。較為常用的辦法是緊發排軟件中的顏色稱號為準，將相同專色的稱號在各類軟件的調色板中重新命名為統一的稱號。

Therefore, if the data file needs to be used in more than two kinds of software, before the integrated color separation output, we must pay attention to the need to unify the use of the same spot color title. The commonly used method is that the color titles in the tightening arrangement software are accurate, and the same spot color titles are renamed as unified titles in the palettes of various software.

2   專色加網的角度。

2. The angle of spot color screening.

普通狀況下專色都以實式印刷，很少做網點處置，所以普通很少提到專色加網的角度。但當運用套色的淺網色時，就會存在對專色網點加網角度的設計和修正問題。假使有網點的專色跟隨其他網點印刷的顏色有疊印區域，就必需思索專色加網的角度問題。

In general, spot color is printed in solid central mode, and seldom dot disposal, so the angle of spot color screening is seldom mentioned. But when using the light screen color of the set color, there will be problems in designing and modifying the angle of dot screening. If the spot color with dots follows the color of other dots and has overlay area, it is necessary to consider the angle of spot color screening.

此時，假如專色網點的加網角度與其他顏色加網角度構成的夾角小于30度，會呈現撞網產生龜紋；假如角度互相堆疊，則會招致油墨疊印問題，這些都將形成印刷品顏色的嚴重失真。

At this time, if the angle between the dot screen angle and the other color screen angle is less than 30 degrees, it will appear to bump into the screen and produce tortoise lines; if the angle stacks with each other, it will cause the problem of ink overlay, which will form a serious distortion of the color of printed matter.

另外，專色的加網角度在軟件中普通都會預設為45度（45度均被以為是人眼感知舒適的角度，讓網點排列在與程度和垂直線成相等角度的方向上能夠減少人眼對網點的發覺才能，）若是一個雙色彩影像或是數據文件中既有印刷四色黑成外（普通在四色加網印刷中，將黑網點放在45度，黃為0度、品紅為15度、青為75度，）又有專色，或者是有兩個以上專色，則在分色加網時都會以45度輸出，所以在對專色運用淺網時，假如有可能與其他加網顏色有疊印，則必需在分色輸出時開啟軟件顏色設定或打印設定的對話框，對專色加網角度停止修正。

In addition, the dot screening angle is usually set to 45 degrees in software (45 degrees are considered to be the most comfortable angle for the human eye to perceive, so that the dots are arranged in the same direction as the degree and vertical line can reduce the human eye's ability to detect dots). If there is printing in a two-color image or data file. Four-color screen printing (usually in four-color screen printing, the black dots are placed at 45 degrees, yellow is 0 degrees, magenta is 15 degrees, green is 75 degrees), there are spot colors, or there are more than two spot colors, in the color separation screen will be 45 degrees output, so in the use of light screen for spot color, if it is possible to overlap with other screen colors. The dialog box of software color setting or printing setting must be opened when the color separation output, and the correction of spot color screening angle must be stopped.