ISO/TR 19312:2026

• Abstract:

  This document presents an analysis of a test method and procedures for predicting print image quality for prints from high-speed inkjet printing systems. Results from an initial set of tests are reported. Based on this method, a set of paper properties and their ISO related standards is given, in addition to those presented in ISO 15397.

• Status: Published
• Publication Date: 08-Jun-2026
• ICS: 35.180 - IT Terminal and other peripheral equipment
• Technical Committee: ISO/TC 130 - Graphic technology
• Drafting Committee: ISO/TC 130/WG 4 - Media and materials
• Current Stage: 6060 - International Standard published
• Start Date: 09-Jun-2026
• Completion Date: 09-Jun-2026

ISO/TR 19312:2026 is an ISO Technical Report on predicting print image quality for high-speed inkjet printing systems from combinations of paper properties. It analyses a test method and procedures, reports initial test results, and gives paper-property metrics that paper manufacturers and press users can use alongside ISO 15397 when selecting media for high-speed inkjet printing.

What does ISO/TR 19312:2026 specify?

ISO/TR 19312:2026 specifies an analysis of how paper-property measurements can be used to predict print image quality for high-speed inkjet printing. The technical content is organized around a property list, the related measurement standards, an example calculation method, and a worked prediction example.

Clauses 4 and 5 are the practical core. Clause 4 lists the paper properties that can be communicated for high-speed inkjet printing, while Clause 5 links those properties to the measurement standards or methods used to determine them. Clauses 6 and 7 show how combinations of those properties are used in a statistical prediction model and illustrate the approach with measured papers and press results.

The report is intended as a screening aid. In practice, that means it can help narrow down paper choices for a press, but selected media still need validation for image quality and other performance aspects such as reliability, image permanence, and transfer.

What are the key requirements of ISO/TR 19312:2026?

ISO/TR 19312:2026 is mainly a measurement-and-prediction guide rather than a prescriptive product standard. Its key points are the paper metrics to communicate, the linked test methods, and the statistical way those metrics are combined to predict print quality.

Paper properties to communicate

Clause 4 gives the set of paper properties that paper manufacturers may communicate for high-speed inkjet printing. The list includes contact angle of water at three times after droplet contact, hygroexpansivity, liquid penetration, silicon content, surface pH, and surface roughness by PPS (Parker Print-surf).

In practice, this matters because the report is aimed at media selection. The data are described as representative of typical paper quality, so they are suited to comparing paper grades rather than tracking batch-by-batch variation.

Linked measurement standards

Clause 5 ties most properties to established ISO methods. Contact angle of water is measured by ISO/TS 14778, hygroexpansivity by ISO 8226-1, water absorptiveness by ISO 535, surface pH by ISO 6588-1, and PPS roughness by ISO 8791-4.

This matters because the report is built for technical communication between paper makers, press makers, and users. Using named methods makes results easier to compare across organizations and helps avoid ambiguous in-house measurements.

Liquid interaction is treated as an early-stage phenomenon

Clause 5.4 treats liquid penetration as a useful metric for the first milliseconds after contact, even though it is not standardized in the same way as some of the other properties. The clause also notes that water absorptiveness is often measured instead of, or in addition to, liquid penetration.

In practice, this tells a reader to think about the earliest ink-paper interaction, not only final drying. For selection work, that early behavior can be important for image formation on inkjet presses.

Silicon content and surface pH are included as selection signals

Clause 5.6 allows silicon content to be measured by X-ray fluorescence spectrometry (XRF), atomic absorption spectroscopy, or another suitable analytical method. Clause 5.7 uses the pH value of the aqueous cold extract, and notes that surface pH is of special interest.

For users, this means the report does more than look at appearance or smoothness. It also points to chemical properties that can influence how ink interacts with coated or uncoated papers.

The prediction method is statistical

Clause 6 explains that the report uses a statistical, black-box style approach. It presents logistic regression as the example method for predicting whether print image quality will be acceptable from several paper measurements taken together.

This is important because the report does not claim that one paper property alone explains print quality. Instead, it says combinations of properties can be used to estimate likely performance even when the underlying paper-ink interactions are complex.

Overfitting must be controlled

Clause 6.5 warns that a model can fit the training data too closely and fail on new papers. The report points to standard safeguards: keep training and test data separate, reduce the number of parameters, regularize the model, and use more datasets when possible.

For a buyer or quality manager, this means a model result should be treated as a screening output, not a final guarantee. The report also notes that the ratio of datasets to coefficients should be at least 3 and ideally more than 5.

The worked example shows how the method is applied

Clause 7 applies the approach to 20 papers and three presses, with visual assessment done by each press manufacturer. It shows how parameter combinations are selected with leave-one-out cross-validation (LOOCV) and reports example prediction scores for the presses.

This gives users a model for reporting their own trials in a comparable way. It also shows that the same method can be used to compare presses, papers, and measurement sets.

What terms does ISO/TR 19312:2026 define?

• Contact angle - the angle used to describe how a liquid droplet sits on a solid surface, which helps indicate wetting behavior.
• Hygroexpansivity - the length change of paper or board when it moves between specified humidity conditions.
• Parker Print-surf roughness (PPS) - a roughness measure based on the mean gap between paper and a flat circular land under specified pressure.
• pH - the acidity value based on hydrogen ion activity, used here for aqueous paper extracts.
• Liquid penetration - the rate at which liquid enters paper through spaces or capillaries between fibres, especially in the first milliseconds after contact.
• High-speed inkjet printing - inkjet printing used in industrial applications with the capability of printing more than a few thousand sheets per hour.
• Precoating - applying a material immediately before ink jetting to control how colorants behave on the substrate surface.

Who uses ISO/TR 19312:2026?

ISO/TR 19312:2026 is used by paper manufacturers, printing press manufacturers, and people who select or qualify papers for high-speed inkjet printing. It is also relevant to commercial printing, publishing, packaging, transactional documents, direct mail, and book printing.

In practice, paper manufacturers can use it to describe paper grades with measurements that matter for inkjet performance. Press manufacturers can use it when testing digital presses and comparing results across systems, and users can use it to reduce trial-and-error when choosing papers for a given press.

Which standards are used with ISO/TR 19312:2026?

• ISO 15397 - gives the baseline communication of graphic paper properties; ISO/TR 19312:2026 adds further paper-property data.
• ISO/TS 14778 - provides the measurement basis for water contact angle.
• ISO 8226-1 - provides the measurement basis for hygroexpansivity.
• ISO 535 - provides water absorptiveness by the Cobb method, used as an alternative or addition to liquid penetration.
• ISO 6588-1 - provides the measurement basis for pH of aqueous extracts.
• ISO 8791-4:2021 - provides the PPS roughness method.
• ISO 186 - can be used for sampling when sampling is needed.
• IEC 62899-201:2016 - is cited in a note on surface pH measurement in the example work.

What does the ISO/TR 19312:2026 document contain?

ISO/TR 19312:2026 contains a property list, a set of related measurement standards, and a statistical example of print-quality prediction. It also includes figures showing the black-box concept, class boundaries, logistic regression relationships, and LOOCV, plus formulas for the prediction model.

The worked example uses 20 papers, measurement data for several paper properties, and visual assessments from three presses. It then shows how parameter selection, overfitting control, and coefficient values are used to estimate the probability of acceptable print image quality for a new paper.

Technical
Report
ISO/TR 19312
First edition
Graphic technology — Analysis
2026-06
of a method for predicting print
image quality for prints from high-
speed inkjet printing system from
combinations of paper properties
Reference number
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 List of paper properties for high-speed inkjet printing . 3
5 Standards related to paper property measurements . 3
5.1 General information useful for technical communication .3
5.2 Contact angle of water .3
5.3 Hygroexpansivity.3
5.4 Liquid penetration .3
5.5 Water absorptiveness .4
5.6 Silicon content .4
5.7 pH value .4
5.8 Surface roughness .4
6 Example calculation method using listed paper properties and measurement standards
that can be used for paper selection . 4
6.1 General .4
6.2 Outline .5
6.3 Typical approach .5
6.4 Example procedure for prediction of image quality .6
6.5 Caution for overfitting .9
7 Example of prediction . 9
7.1 General .9
7.2 Papers .9
7.3 Paper properties tested .10
7.4 Visual assessment .10
7.5 Model used .10
7.5.1 General .10
7.5.2 Model building .11
7.6 Table of results . 13
7.7 Example of calculation.14
Bibliography .15

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
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with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
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This document was prepared by Technical Committee ISO/TC 130, Graphic technology.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
Inkjet printing is a non-contact digital printing method that creates text or images by accurately ejecting
tiny droplets of ink onto a printing substrate. Advanced digital printing technologies called high-speed
inkjet printing systems are made to produce high-quality results quickly on a range of substrates. These
systems combine the flexibility of inkjet technology with production-level speeds, often exceeding hundreds
of meters per minute, making them ideal for large-scale applications such as transactional documents,
direct mail, packaging, and book printing. Currently there is a strong growth in the market share for inkjet
printing.
The careful selection and compatibility of inks and substrates are critical to the efficient operation of
high-speed inkjet printing devices. Inkjet printing, as opposed to conventional printing methods, entails
ejecting tiny ink droplets onto the substrate at high velocities and speed, often without making any contact.
Regarding material interaction, drying performance, adhesion, print quality, and long-term durability, this
non-impact approach offers both advantages and limitations.
Colour consistency, optical density, edge definition, and rub resistance are all determined by the interaction
between the substrate surface and ink chemistry. Manufacturers are increasingly working together to
create integrated ink-substrate systems, which match certain ink sets with printing substrates, in order
to maximize performance. This alignment reduces trial-and-error in industrial environments and ensures
reliable performance across long production runs.
An ad hoc group focused on high-speed inkjet printing with printing heads covering the full width of the
substrate and using water-based inkjet inks. Although the method was developed based on this technology,
it is likely to be appropriate for all inkjet technologies.
Water based ink jet inks contain a large percentage of water which need to be either absorbed by the
substrate surface in a defined manner to ensure high image quality and text reproduction or be kept on
the surface of the substrate for rapid evaporation by heaters within the press (or a combination of both).
There have been numerous specialized paper developments to support high-speed inkjet printing. These
increase paper manufacturing costs through development of printing system (printing head technology and
ink) specific ink receiving layers. For this and other reasons, many users of high-speed inkjet printers wish
to use papers already on the market and typically developed for conventional printing.
Since inkjet ink interaction with paper is very different from that in conventional printing processes,
different paper properties need to be considered compared to conventional printing. Knowledge on paper
properties influencing inkjet ink and paper interaction is limited and dependent on ink formulation which
varies between different system providers.
Therefore, an industry group was formed to perform a joint project to improve understanding of the
interaction of inkjet ink and paper. The aim was to develop an ISO document to improve the process of
selection of conventional paper grades for high-speed inkjet printers by having additional information
on papers. During this, project partners chose 20 paper grades showing both good and bad print quality
on different high-speed inkjet presses. A set of paper properties was identified by the industry group as
being most likely to influence print image quality based on the experience of group members. The paper
samples were pooled, and each partner performed measurements on one or more of these paper properties.
These papers were later printed on high-speed inkjet by some of the members of the industry group and the
quality of the prints were evaluated according to these partners print quality requirements. As expected,
no single paper property can be identified as being related to print quality. The investigation showed
that combinations of paper properties can be used to predict good inkjet print quality through statistical
[9]
analysis even without a scientific understanding of the interactions occurring between paper and ink.
This statistical method makes it possible to predict print quality without specifying either the interaction
between paper and ink, or the printing conditions (such as printer setting) nor the evaluation method of
image quality (criteria of visual assessment). In other words, this can be called a "black box approach." See
Figure 1.
v
Figure 1 — Black box approach to prediction of print image quality
The "black box approach" is not an approach specifically adopted for this prediction method. Prediction
using statistics is a method of predicting an event by analysing available data. Particularly, when the causal
relationship between the available data and the event to be predicted is complex (not scientifically or
theoretically clear), the black box approach is used, and the prediction results are obtained probability of
the prediction.
Typical examples include complex systems such as demand forecasting in markets, stock price forecasting,
weather forecasting and drug efficacy testing. In these examples, it is difficult to identify the cause of the
results. However, using statistical analysis of the data, when certain patterns can be found in the data, a
specific outcome with a high probability can be found. In other words, while science places emphasis on
"why something happens" (causality), if the "reproducibility of patterns" between data and outcomes can be
identified through statistical analysis, "what is likely to happen" can be predicted without knowing "why it
happens" or "what operations were performed."
This document describes a set of paper property metrics that can be provided by paper manufacturers
to enable reliable high-speed ink jet printing on paper developed for standard conventional printing
(particularly lithographic printing). Paper measurement international standards developed by the paper
industry are referenced in those metrics. These data can be provided in addition to those data already
communicated according to ISO 15397. Further, this document provides an overview of prediction methods.
It is anticipated that press manufacturers will use this test method to test their digital presses and where
that is done the technology used (ex. UV cured etc) can be identified so that other manufacturers can use
these results as the starting point for testing.
The method described in this document is a screening method, and further validation can still be required
for the selected media, not only in terms of image quality but also in other attributes such as reliability,
image permanence, transfer, etc.
In addition, although this prediction method was validated using standard-frequency water-based inkjet
printing on coated and uncoated papers, a black-box approach (based on statistical principles) suggests that
it will also work in systems employing high-frequency piezo systems with matched low-surface-tension ink
formulations.
vi
Technical Report ISO/TR 19312:2026(en)
Graphic technology — Analysis of a method for predicting
print image quality for prints from high-speed inkjet printing
system from combinations of paper properties
1 Scope
This document presents an analysis of a test method and procedures for predicting print image quality for
prints from high-speed inkjet printing systems. Results from an initial set of tests are reported.
Based on this method, a set of paper properties and their ISO related standards is given, in addition to those
presented in ISO 15397.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
contact angle
angle between a plane solid surface and the tangent drawn in the vertical plane at the interface between the
plane solid surface and the surface of a droplet of liquid resting on the surface
[SOURCE: ISO 15989:2004, 3.4]
3.2
hygroexpansivity
change in length that occurs in a given length of paper or board when the relative humidity with which it is
in equilibrium is raised from a specified lower relative humidity to a specified higher relative humidity
Note 1 to entry: The change in length is expressed as a percentage of the given length when the paper or board is in
equilibrium with 50 % relative humidity. A contraction of the test piece is regarded as negative hygroexpansivity.
[SOURCE: ISO 8226-1:1994, 3.1]
3.3
Parker Print-surf roughness
PPS
mean gap between a sheet of paper or board and a flat circular land pressed against it under specified
conditions
Note 1 to entry: It is expressed in micrometres and calculated based on the airflow between the measuring land and
the test piece.
[SOURCE: ISO 8791-4:2021, 3.1, modified — original term was print-surf roughness]

3.4
pH
decadal logarithm of the hydrogen ion activity multiplied with (−1)
m 
 
a 


HHm,
H
 
 
pHlogl og
00 
 
m m
 
 
where
+
a is the activity of the hydrogen ion, in mol/kg;
H
m is the standard molality (1 mol/kg);
+
γ is the activity coefficient of the hydrogen ion;
m,H
+
m is the molality of the hydrogen in, in mol/kg.
H
[SOURCE: ISO 23497:2019, 3.2]
3.5
liquid penetration
rate of liquid entering into the paper substrate through the space or capillary between paper fibres
Note 1 to entry: Water is often used in place of ink in order to provide a reference measure of liquid penetration.
3.6
high-speed inkjet printing
inkjet printing used in commercial printing, publishing, packaging, and other industrial applications, which
has capability of printing more than a few thousand sheets per hour
Note 1 to entry: No restrictions on print engine (type of inkjet head and configuration), paper feeding method,
substrates used, ink used, and resolution.
3.7
precoating
process of applying materials to control the behaviour of the colorants on the surface of the substrate
immediately before jetting the ink droplets and prior to drying or curing
Note 1 to entry: This is generally an in-line printing process. Figure 2 shows an example of precoating in ink jet
printing.
Note 2 to entry: Various types of materials can be used such as emulsions, gels, and solutions; they can be water based
or solvent based.
Key
1 precoating
2 inkjet inks
3 drying/curing
4 preconditioning layer
5 substrate
Figure 2 — Typical example of precoating as an in-line process

4 List of paper properties for high-speed inkjet printing
For high-speed inkjet printing, paper manufacturers may choose to communicate the data shown in Table 1.
For convenience, this can be provided as an addition to data already provided based on ISO 15397.
All data communicated are data representative for typical qualities of papers. No batch-specific data is
necessary.
Table 1 — List of criteria of paper properties
Items Standard for each test method Clause No. described
Contact angle of water after 300 ms ISO/TS 14778 5.2
Contact angle of water after 1 100 ms ISO/TS 14778 5.2
Contact angle of water after 3 100 ms ISO/TS 14778 5.2
Hygroexpansivity ISO 8226-1 5.3
a
Liquid penetration none 5.5
Silicon content 5.6
Surface pH ISO 6588-1 5.7
Surface roughness PPS (Parker-Print surf) ISO 8791-4 5.8
a
If a measurement according to the international standard is required, water absorption as described in 5.5 can be used as an
alternative, although it does not measure the same phenomenon.
5 Standards related to paper property measurements
5.1 General information useful for technical communication
When communicating the properties specified in Clause 4, the related standard specified in this clause
(Clause 5) to determine the property can be used, and the name of the standard cited.
When sampling is required, the procedure defined in ISO 186 can be used.
5.2 Contact angle of water
The contact angle of water can be communicated based on measurements made according to ISO/TS 14778.
After the ink droplet contact with the surface of paper are chosen, the shortest time possible after the ink
droplet comes into contact with the paper, an intermediate time, and a long time before it is completely dry,
for example 300 m
...