Specifications
for Mat/Mounting Board
for Photographic Materials
Specification Number 400-402-8/19/02
This specification is provided as a public service by the Preservation
Directorate of the Library of Congress. Any commercial reproduction
that implies endorsement of a product, service or materials, in any
publication, is strictly prohibited by law. This Specification is written
for L.C. purchasing purposes and is subject to change when necessary.
I. General Specifications - II.
Product Requirements - III. Inspection
A. Stock Composition
- Pulp:
- Fiber: The stock should be made from rag or
other high alpha-cellulose content pulp. It must not contain any
post consumer waste recycled pulp.
- Lignin: The stock must give a negative reading
for lignin as determined by the phloroglucinol test when tested
according to ASTM D 1030, X5 spot stains and shall have a Kappa
number of 5 or less when tested according to TAPPI T 236 cm-85.
- Impurities: The stock must be free of metal
particles, waxes, plasticizers, residual bleach, peroxide, sulfur
(which will be less than 0.0008% reducible sulfur as determined
by TAPPI T 406 om-88), and other components that could lead to
the degradation of the paper and artifacts stored therein.
- Metallic Impurities: Iron must not exceed 150
ppm and copper shall not exceed 6 ppm when test according to TAPPI
T 266.
- Optical Brighteners: The stock must be free
of optical brightening agents.
- pH:
The stock should have a pH value within a range of 8.0 - 9.5 ± 0.5
as determined by TAPPI T 509 om-88, cold extraction (modified by slurrying
sample pulp before measurement).
- Alkaline Reserve:
The alkaline reserve should be a minimum of 2% and a maximum of 5%
calculated as CaCO3 when tested according to ASTM 4988-89.
- Sizing:
Only neutral or alkaline sizing shall be used. No alum rosin or rosin
sizing should be used as determined by ASTM D 549-88.
- Photographic Activity Test:
The stock must pass the Photographic Activity Test (P.A.T.). Tests
to be conducted and results reported as described in ISO 14523-1999,
or latest revision. Tests should be performed by Image Permanence
Institute (c/o Rochester Institute of Technology, Frank E. Gannett
Memorial Building, P.O. Box 9887, Rochester, NY 14623-0887. Tel.:
716-475-5199, FAX: 716-475-7230) or other pre-approved laboratory.
- Thickness:
2 ply: (28 ±2 pts.), 4 ply:(54 ± 2
pts.), 6 ply: (85 ± 2 pts.)
- Color:
The color of the stock will be specified with a sample included with
the purchase order. Color must be continuous throughout the thickness
of the stock.
Bleeding: The color must show no bleeding when soaked
in distilled water for 48 hours while held under suitable weight in
contact with white bond paper. The color must not rub off.
Retention: The color of the stock must not change
more than 5 points of brightness measured by directional reflectance
at 457 nm (TAPPI T 452 om-92), when exposed 24 hours to a Xenon arc
lamp in an Atlas Weatherometer under the following conditions: Irradiance
Level: 1.0 watts/m2 at 420 nm. Inner filter: Borosilicate glass.
Outer filter: clear soda lime glass. Black panel temperature: 50°C.
Wet bulb depression: 8.5°C.
- Surfaces:
The surface of the stock will be specified with a sample included with
the purchase order. There must be a smooth to moderate texture with
no repetitive pattern such as simulated textile patterns unless otherwise
specified. The surfaces of the stock must be free of fingerprints,
dirt, bubbles, knots, shives and other abrasive particles.
- Grain:
The grain of the outer plies of the board must run in the long direction
of all boards, unless otherwise specified.
- Adhesive:
If an adhesive is required, it must not soften or run. The adhesive
must not cause the stock to become transparent or alter the color
of the stock. The adhesive must not yellow, discolor, or fail (causing
delamination) over time. When used, the adhesive must not extend
beyond the joined area.
- Moisture Range:
To prevent warping, waving, or curling, the equilibrium moisture range
should be between 4 and 7% at time of manufacture.
- Additional Components:
Additional components included in the mat board which may or may not
improve the performance of the mat board are not considered within
the scope of this specification. Mat board manufactured with additional
components will be considered as not meeting the specification.
B. Identification
There should be no identification marks on the board.
C. Packaging
- Inner Wrapper:
Boards should be grouped and wrapped in paper or polyolefin according
to size and ply.
I.D.: Each package must plainly identify the type,
size and number of items within, the name of the supplier or manufacturer,
year of manufacture, manufacturing run or batch number, actual pH, "P.A.T." and
PHOTO.
- Outer Wrapper:
The items must be packed in standard commercial containers which are
constructed to ensure that they arrive at the Library of Congress
in dry, undamaged condition. If straps are used, the boards must
be protected from possible damage caused by the straps.
I.D.: The outside of each container must be identified
by type, size and number of items within, Purchase Order or Contract
number and PHOTO.
D. Testing
- Responsibility:
The supplier is responsible for meeting all the requirements specified
herein. The Library of Congress has the right to perform any of the
tests set forth in the specification where such tests are deemed
necessary to ensure that supplies conform to prescribed requirements.
- Sampling: To sample for testing, shipments will
be sampled according to MIL-STD-105E at inspection level S-2 with an
acceptance quality level of 2.5 percent defective from each lot offered.
Copies of MIL-STD-105E are available from Naval Publications and Forms
Center, Standardization Document Order Department, Building 4, Section
D, 700 Robbins Avenue, Philadelphia, PA 19111-5094.
- Methods: Tests will be conducted in accordance with
specified test methods of the American National Standards Institute
(ANSI), the American Society for Testing and Materials (ASTM), and
the Technical Association of the Pulp and Paper Industry (TAPPI). Publications
describing these tests may be ordered directly from the technical associations
at the following address:
- ANSI, 1430 Broadway, New York, NY 10018
- ASTM, 1916 Race Street, Philadelphia, PA 19103
- TAPPI, One Dunwoody Park, Atlanta, GA 30348
- Tests:
Requirements
|
Test Method |
Lignin |
negative/Kappa 5 |
ASTM D 1030, X5 or TAPPI 236 cm-85 |
Reducible Sulfur |
< 0.0008% |
TAPPI T 406 om-88 |
Iron |
< 150 ppm |
TAPPI T-266 |
Copper |
< 6 ppm |
TAPPI T-266 |
pH |
8.0-9.5 pH |
TAPPI T 509 om-88. cold extraction, slurried pulp |
Alkaline Reserve |
2 - 5% |
ASTM D 4988-89 |
Alum Rosin Sizing |
negative. |
ASTM D 549-88 |
"P.A.T." |
negative |
ISO 14523-1999 or latest revision |
Color Bleeding |
none |
See above, "I. 7. Color" |
Color Retention |
< 5 points |
TAPPI T 452 om-92 |
E. Quality Assurance Inspection
Sampling: To evaluate non-tested requirements, shipments
will be sampled according to MIL-STD-105E at inspection level S-2 with
an acceptable quality level of 4.0 percent defective from each lot offered.
A. Construction
- Sizes must be accurate.
- The boards in any order must come from the same batch or run number.
B. Workmanship
- Edges should be cut square and clean.
- The board must be free of bent corners and delamination of plies.
- Surfaces must be free of fingerprints, specks, foreign material (dust,
dirt, insects, mold, etc.) and scarring or incising of the board.
C. Dimensions
Will be given on the purchase order.
An examination will be made to determine whether the items comply with
all the Requirements. The qualities and characteristics which will be
examined include the following.
Testing Inspection
- Materials must pass all composition and performance specifications
stated in "I. General Specifications"
Visual Inspection
- Mat boards in any one order must come from the same batch or run
number.
- Color must match the submitted sample.
- Surface texture must match the submitted sample.
- Board stock must be free of knots, shives and other abrasive particles.
- Surfaces must be free of fingerprints, specks, foreign material (dust,
dirt, insects, mold, etc.) and scarring or incising of the board.
- Edges must be cut square and clean.
- Sizes must be accurate.
- Mat boards must be free of bent corners and delamination of plies.
- Adhesives must not soften or run, nor cause the stock to become transparent
or alter the color of the stock. The adhesive must not yellow or discolor,
fail (causing delamination), or extend beyond the joined area.
- Planar distortion should be non-existent or minimal.
- Identification markings should not appear on the mat board.
- The inner wrapper must be according to size and identified as specified
in "I. D. Packaging."
- The outer wrapper must ensure arrival in dry, undamaged condition
and be identified as specified in "I.D. Packaging."
FAILURE TO MEET ANY OF THE SPECIFICATIONS WILL BE CAUSE FOR
REJECTION.