Sheet manufacturing apparatus
US-2018355556-A1 · Dec 13, 2018 · US
Method for producing paper, and pitch removal agent
US2017073891A1 · US · A1
| Field | Value |
|---|---|
| Publication number | US-2017073891-A1 |
| Application number | US-201515123528-A |
| Country | US |
| Kind code | A1 |
| Filing date | Mar 11, 2015 |
| Priority date | Mar 11, 2014 |
| Publication date | Mar 16, 2017 |
| Grant date | — |
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Abstract
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Provided is a method for producing paper and a pitch removal agent that can remove pitch efficiently. A pitch removal agent having an average polymerization degree of 300 to 2500, a saponification index of 70 to 88 mol % and satisfying, when the absorbance at a wavelength of 490 nm is designated as y (Abs) and the saponification index as x (mol %), the Numerical Formula (A) below is added to a pulp slurry during production of paper using waste paper in the step of deinking the waste paper by floatation and/or a step earlier: y =−0.0297 x+b (A) (wherein, 70≦x≦88 and 2.80≦b≦3.03).
First claim
Opening claim text (preview).
1 . A method for producing paper using waste paper, comprising adding, to the pulp slurry in the step of deinking the waste paper by floatation and/or a step earlier, a polyvinyl alcohol having an average polymerization degree of 300 to 2500, a saponification index of 70 to 88 mol %, and an absorbance at a wavelength of 280 nm in the ultraviolet absorption spectrum of its 0.1 mass % aqueous solution of 0.1 Abs or more and satisfying, when the iodine absorbance at a wavelength of 490 nm is designated as y (Abs) and the saponification index as x (mol %), the following Numerical Formula (A): [Numerical Formula 1] y=− 0.0297 x+b (A) (wherein, 70≦x≦88 and 2.80≦b≦3.03). 2 . A pitch removal agent added to a pulp slurry during production of paper using waste paper in the step of deinking the waste paper by floatation and/or a step earlier, the pitch removal agent containing a polyvinyl alcohol having an average polymerization degree of 300 to 2500, a saponification index of 70 to 88 mol %, and an absorbance at a wavelength of 280 nm in the ultraviolet absorption spectrum of its 0.1 mass % aqueous solution of 0.1 Abs or more and satisfying, when the iodine absorbance at a wavelength of 490 nm is designated as y (Abs) and the saponification index as x (mol %), the following Numerical Formula (A): [Numerical Formula 2] y=− 0.0297 x+b (4) (wherein, 70≦x≦88 and 2.80≦b≦3.03).
Assignees
Inventors
Classifications
Secondary fibres (working-up waste paper D21C5/02) · CPC title
- D21C5/025Primary
De-inking · CPC title
Agents for preventing deposition on the paper mill equipment, e.g. pitch or slime control (removal of fats, resins, pitch, or waxes D21C9/08) · CPC title
Chemicals therefor · CPC title
- D21C9/086Primary
with organic compounds or compositions comprising organic compounds · CPC title
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Frequently asked questions
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- What does patent US2017073891A1 cover?
- Provided is a method for producing paper and a pitch removal agent that can remove pitch efficiently. A pitch removal agent having an average polymerization degree of 300 to 2500, a saponification index of 70 to 88 mol % and satisfying, when the absorbance at a wavelength of 490 nm is designated as y (Abs) and the saponification index as x (mol %), the Numerical Formula (A) below is added…
- Who is the assignee on this patent?
- Kurita Water Ind Ltd, Nippon Synthetic Chem Ind Co Ltd
- What technology area does this patent fall under?
- Primary CPC classification D21C5/025. Mapped technology areas include Textiles & Paper.
- When was this patent published?
- Publication date Thu Mar 16 2017 00:00:00 GMT+0000 (Coordinated Universal Time) (A1). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 8 related publications on this page (citations in our corpus or others sharing the same primary CPC).