Specifications for Envelope Slings

Specification Number 100-142- 8/26/02

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

I. GENERAL SPECIFICATIONS

A. Stock Composition

Pulp:
- Fiber: The paper 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 tested according to TAPPI T 266.
- Optical Brighteners: The stock must be free of optical brightening agents.
pH:
The paper stock should have a pH value of 8.0 - 9.5 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 a 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 paper 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 version. 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.
Basis Weight:
65 lb. cover stock, uncoated.
Folding Endurance:
The paper stock must meet the minimum requirement of 75 double folds in the machine direction using a 1 kg load. Tests to be conducted according to the MIT Fold Endurance Test as described by TAPPI T 511 om-88, after conditioning according to TAPPI T 402 om-88.
Color:
- White, off-white or as specified on the purchase order.
- 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.
- Retention: The color of the stock on both sides must not change more than 5 points of brightness as 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.

B. Workmanship

Edges will be cut square and clean, and sizes accurate.

C. Identification

There should be no identification marks on the sling.

D. Packaging

Inner Wrapper:
The slings must be wrapped in paper or plastic according to size.
I.D.: Each package must be 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 (± 0.2 pH) and "P.A.T.".
Outer Wrapper:
The items must be packed in standard commercial containers constructed to ensure that the paper arrives at the Library of Congress in dry, undamaged condition.
I.D.: The outside of each container must be identified by type, size and number of items within, manufacturing run or batch number, Purchase Order or Contract number and "P.A.T.".

E. 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 acceptable 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, Pennsylvania 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 addresses:
- 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
Photographic Activity Test	pass	ISO 14523-1999
Basis Weight	65 lb. cover	TAPPI 410 om-93
Color Bleeding	none	See above, "I. 7. Color"
Color Retention	< 5 points	TAPPI T 452 om-92
Folding Endurance	75 MD	TAPPI T 511 om-88, and TAPPI T 402 om-88

F. 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.

II. PRODUCT REQUIREMENTS: Envelope Slings

A. Construction for all enclosures, illustrated below

The slings should be made out of one blank of cover stock.
The corners should be rounded slightly.
The grain should be in the short direction and parallel to the scored crease lines.
Three creases should be scored across the width of the blank at the specified locations.

B. Workmanship

Sizes should be accurate, and edges clean.
Score lines should be at a right angle to the long sides of the blank.

C. Dimensions

When the creases #1 and #3 are folded, the slings must be 1/8" less than the length dimension of the following envelope sizes unless otherwise specified on the Purchase Order or the Contract. All score lines should be located by measuring from the same short edge.

Envelope Size	Sling Size	Score#1	Score #2	Score #3
6 x 9"	5 3/4 x 19 7/8"	2 1/2"	11 1/8"	11 3/8"
7 1/2 x 10 1/2	7 1/4 x 22 7/8	2 1/2	12 5/8	12 7/8
9 x 12	8 3/4 x 25 7/8	2 1/2	14 1/8	14 3/8
9 1/2 x 14 3/4	9 x 31 3/8	2 1/2	16 7/8	17 1/8
11 x 14	10 3/4 x 29 7/8	2 1/2	16 1/8	16 3/8
11 1/2 x 15	11 x 31 7/8	2 1/2	17 1/8	17 3/8

III. INSPECTION: Envelope Slings

An examination will be made to determine whether the items comply with the Requirements Sections. 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

The slings should be made out of one blank of cover stock.
There should be no identification marks on the sling.
The corners should be rounded slightly.
The grain should be in the short direction and parallel to the scored crease lines.
Three creases should be scored across the width of the blank at a right angle to the long side, at the specified locations.
When creases #1 and #3 are folded, the slings must be 1/8" less than the length dimension of the ordered envelope sizes.
Slings must be wrapped according to size and identified as specified
Slings must arrive in dry, undamaged condition

FAILURE TO MEET ANY OF THE SPECIFICATIONS WILL BE CAUSE FOR REJECTION.

Home >> Supply Catalog >> Specifications