US2174095A - Paper manufacture - Google Patents

Description

Patented Sept. 26, 1939 UNITED STATES PAPER MANUFACTURE Wellington G. Reynolds, South Hadley Falls, Mass., assignor to Reynolds Mfg. 00., Holyoke, Mass, a corporation of Massachusetts No Drawing. Application April 21, 1938, Serial No. 203,361

1 Claim.

This invention relates to improvements in paper manufacture and is directed more particularly to the provision of a novel process of making paper which is especially adapted for writing pur- 5 poses.

It is one of the principal objects of the invention to provide a writing paper having a surface which is particularly suitable for pen and ink writing and which has the distinct advantage of not glaringly reflecting light rays as will papers of ordinary manufacture. The paper of this invention may be made economically and, by reason of its non-glaring qualities, it is especially adapted for use in schools, ofiices and other places where it is desired to avoid the difliculties encountered with ordinary papers.

It is another object of the invention to provide paper which by reason of its non-glare features may have a super-calendered finish and at the same time it does not have the glare of supercalendered papers heretofore made, especially under artificial light.

It should, perhaps be stated that it is advisable that writing paper be made in such a way as to have a smooth surface. While this facilitates the easy travel of the writing pen or the like thereover, ordinary smooth surfaces have the disadvantage of producing a distinct glare under light just because of their smoothness.

While a dull-finish paper is not, perhaps, so likely to produce such a glare, such paper is neither suitable for nor intended for writing purposes. That is it tends to actively resist the movement of steel or other pen points and this,

of course, has obvious disadvantages and may even cause writers cramp, nervous disorder, etc.

Accordingly, I have provided, after much experiment and research, a paper which has the desired smooth writing finish yet at the same time has none of the glare-reflecting disadvantages thereof above referred to. That is to say, according to my process, paper is provided which not only has a super-calendered finish particularly adapted for writing purposes but which will definitely not cause a glare under either natural or artificial light.

This is brought about particularly by a correct blending of certain coloring and stock materials, as will shortly appear, so that not only is the paper of desired strength and capable of fine finishing but its surface at least, has a carefully selected tint for eye-ease purposes. According to my process, I do this without interfering with the usual process of manufacture or adding appreciably to its cost, the paper being capable of manufacture on the usual paper machines and of subsequent high calendering to produce what is generally referred to in the trade as a super-calender finish.

While the invention may be practiced in vari- 5 ous ways without departing from the spirit or scope of the invention, I will describe the process with reference to the form at present preferred and with respect to about 1700 pounds of paper stock. 10

In order to provide an economical paper which has the desired strength and other usual qualities, I have found it desirable that about 60% of that stock consist of bleached sulphite. Then, I add about 20% of soda pulp and approximately 15 20% of unbleached sulphite. Such stock has the ability to make a strong sheet and it is capable of blending readily and efiiciently with the coloring materials about to be described for the best results. 20

The tinting means may be introduced into the stock at various stages of the paper's manufacture, but preferably it consists of about of an ounce of what is known as soluble American Blue (Index No. 1288), formerly Prussian Blue 25 and about 6% ounces of what is known as Paper Yellow C. H. (Index No. 365).

The proportions of the blue coloring material may be from A, of an ounce to 1 ounces and the proportions of the yellow may vary from 5 to 30 8 ounces, all depending on the condition of the pulp. However, I have found that the specific proportions of these substances to about 1700 pounds of the particular stock referred to produces substantially uniform results and satis- 35 factorily gives to that stock the desired tint.

The mass may then be worked in the paper machine in the usual manner and after the paper Webis formed, it is then preferably subjected to a calendering operation in the usual way and 40 later a super-calendering step. This gives to the web a high smooth finish which is particularly adapted to receivewriting from a pen With a minimum of hand effort.

The finished papermade in accordance with 45 this process has a light greenish tint and has the positive quality of absorbing the light rays cast upon its surface, rather than reflecting them back in the nature of a glare. Further, not only does the paper thus produced have a finish equal 50 to that of the most superior writing paper, but it can be readily and neatly written upon and the writing matter thereon can be read at any angle relative to the source of light without glare.

While I have described the invention in great detail and with respect to the present preferred form thereof, it is not desired to be limited thereto since many changes and modifications may be made therein without departing from the spirit and scope of the invention. What it is desired to claim and secure by Letters Patent of the United States is:

As a new article of manufacture, a sheet of writing paper having a highly calendered but non-glare surface formed from paper stock corisisting of a mixture of approximately 20% soda pulp and 60% bleached sulphite and about 20% unbleached sulphite and containing about of an ounce of American Blue, Index No. 1288, and about 6% ounces of Paper Yellow C. H., Index No. 365, to every 1700 pounds of said stock.

WEILINGTON G. REYNOLDS.